Covid-19 and the quality of life of people with dementia and their carers-The TFD-C19 study.

INTRODUCTION: COVID-19 has placed unprecedented pressure on dementia health and social care systems worldwide. This has resulted in reduced services and support for people with dementia and their family carers. There are gaps in the evidence on the impact of the pandemic on Quality of Life (QoL). We carried out a study on the impact of the pandemic on the QoL of a group of people with dementia and their family carers who were part of a larger existing cohort study.
METHODS: We quantitatively measured QoL, on two occasions during the two national lockdowns in 2020 and compared these data with those obtained when they entered the study (before the pandemic). Measures used included: DEMQOL-Proxy, Clinical Dementia Rating Scale and C-DEMQOL. To understand how QoL changed over time, a repeated measures ANOVA was run for each dependent variable with the following variables entered as co-variates: duration in study, baseline dementia severity, gender of the family carer, gender of the person with dementia, family carer relationship, dementia type, living status, age of the person with dementia, and age of the family carer.
RESULTS: 248 participants took part in the study. QoL scores did not significantly decline between either time period for the person with dementia or their family carer. There was variation in subgroups; with co-resident status, carer relationship, gender of the person with dementia, age of the person with dementia, and baseline cognitive status influencing QoL outcomes in family carers. DISCUSSION: It is striking that people with dementia and their carers did not report a decline in QoL during the pandemic or in the months following restrictions suggesting the possibility of resilience. Variation in subgroups suggests that specific groups of family carers were more vulnerable to lower QoL; indicating the need for more tailored, nuanced support during this period.

Introduction

The COVID-19 pandemic has placed unprecedented pressure on health and social care systems worldwide as they respond to the virus. This has resulted in a significant impact on the availability of services and support for people with dementia and their family carers. In the UK, COVID-19 related public health restrictions led to the suspension of most face-to-face social support services, at least temporarily, with social support service usage for people with dementia decreasing significantly since the pandemic [1, 2]. In addition, social isolation and restrictions meant that other sources of informal support, such as non-resident family and social networks, are also compromised. The wider literature suggests that people with long-term conditions are particularly vulnerable during national emergencies, and the World Health Organisation [3] has acknowledged that older adults, particularly those with dementia, may be severely psychologically impacted during the COVID-19 pandemic.

Social distancing restrictions have affected the ability of family carers to access support, attend support groups and has made caring for the person with dementia increasingly difficult, resulting in increased family carer stress levels [4]. A UK survey of 569 older adults and people affected by dementia found that a reduction in social support services received during the pandemic was significantly associated with reduced levels of wellbeing in family carers [1]. An online study in July 2020 of family carers of people with dementia described increased responsibilities, strain on the caring relationship, and feelings of exhaustion and guilt [5] It has been reported that 73% of family carers experienced an increase in caring responsibilities in lockdown, largely due to worsening dementia symptoms in the person they care for, with 95% of respondents reporting that the increase in caring duties had a negative impact on their mental and/or physical health [6]. This included feeling exhausted, anxious, depressed, and having problems sleeping. Additionally, disorientation, confusion, and distress in people with dementia has significantly increased anxiety and burden in family carers [7]. A Greek survey of 204 family carers found cognitive, emotional, and physical decline in the people with dementia with a consequently increased carer workload [8]. Similarly, in Argentina the level of burden carers experienced was reported to be higher after four weeks of lockdown, especially when caring for people with advanced stages of dementia [9]

It is clear that while social restrictions were put in place to protect vulnerable people from COVID-19, they have also led to increased burden and strain on family carers of people with dementia, with a negative impact on their mental health. However, there remain important gaps in the evidence base particularly in terms of overall impact as measured by Quality of Life (QoL). QoL can be defined as the subjective assessment of the position of the individual in their life, in the context to their culture and value system, relating to their goals, expectations and concerns, impacted by their physical and psychological health, level of independence, and social relationships [10]. Living with, or caring for somebody with dementia impacts upon all of the factors known to affect QoL, it is likely that Covid-19 and associated restrictions may have been more impactful for this group of people. There is therefore a need to measure the impact of Covid-19, using condition-specific measures of QoL, which are tailored to the challenges and realities of daily life with dementia. There is also a need for further COVID-19 research in dementia that uses large and well characterised cohorts of people with dementia with measurement of QoL of carers and people with dementia.

We therefore carried out a study of the impact of the pandemic on a group of people with dementia and their family carers who were part of an existing cohort study, the evaluation of the Time for Dementia Programme [11, 12]. Time for Dementia is an undergraduate educational programme in the South-East of England and as part of its evaluation, before the pandemic, the QoL of family carers of people with dementia, as well as the social functioning, QoL, and illness severity of the person with dementia were assessed. In this study (TFD-C19), we followed up this participant group and repeated the same measures during the two national lockdowns in 2020 with the aim of investigating the impact of the COVID-19 pandemic and restrictions compared with existing pre-pandemic data. Our study aim was to understand how COVID-19 had affected the QoL, wellbeing, and care of people with dementia and their family carers.

Methods

Study design

TFD-C19 was nested into the Time for Dementia (TFD) study. We quantitatively measured QoL, social functioning and disease severity during the two national lockdowns in 2020 and compared these data with those obtained when they entered the programme (before the pandemic). The study was approved by the NHS Health Research Authority London Queen Square Research Ethics Committee (15/LO/0046).

Contextual information

On 26 March 2020, lockdown measures were implemented in England. Those considered clinically vulnerable were asked to shield, which included recommendations to stay at home and avoid social contact. Most non-urgent, routine, healthcare appointments were cancelled. On 1 June 2020 easing of restrictions occurred, those that were shielding were allowed outdoors with people living outside of their household. In June, other businesses and non-urgent healthcare appointments began to reopen, although many support services for people with dementia did not reopen. From 13 June 2020 those living alone were allowed to spend time with one other household as part of a “support bubble”, without social distancing measures. This new rule did not apply to those who were shielding. On 1 August 2020, those shielding no longer needed to isolate. Measures continued to ease (outside of localised restrictions, not affecting the South East of England) until 5 November 2020 when a second national lockdown was put into place. A third national lockdown was put in place on 5th January 2021.

Participants and consent

Participants were family carers of people with dementia who were taking part in the TFD study evaluation. The study definition of family carers included married and unmarried partners, children, siblings, extended family and close friends. The term ‘family carers’ is used since it was preferred by our lived experience advisory group. Due to the difficulty in assessing capacity over the telephone, the people with dementia on the programme were not interviewed for this study. Existing study participants were approached by a research worker. Those who were interested were sent a study information sheet, and verbal consent was given by those who wanted to take part. An appointment was made to collect measures by telephone.

Study assessments

All carers completed the same battery of instruments at Time 2 (May/June 2020 during the first national lockdown) and Time 3 (October/November 2020 part-way through the second national lockdown) as they had at Time 1 baseline assessment when joining TFD (March 2018 –March 2020).

All measures were completed at each time point, and are described below:

DEMQOL-Proxy [13]

A proxy measure of QoL in people with dementia with 31 items. The measure has two domains; functioning and emotions. Scores range from 31–124, with higher scores indicating a better QoL for the person with dementia. Internal consistency for the measure is α = 0.87–0.92, and test-retest reliability is ICC = 0.67–0.84 [14].

C-DEMQOL [15]

A measure of QoL in family carers of people with dementia. A 30-item measure with scores ranging from 30–150 with higher scores representing better QoL for family carers. The measure provides a rating for overall QoL, which is made up from five sub-scales: meeting personal needs, carer wellbeing, carer-patient relationship, confidence in the future, and feeling supported. Reliability for the total QOL score, is good; with ω = 0.97, with a range of 0.82 to 0.95 for each of the five sub-domains.

The clinical dementia rating scale (CDR) [16]

A proxy report of cognitive and functional performance in dementia. A semi-structured interview is undertaken to rate cognitive performance in 6 domains, memory, orientation, judgement and problem solving, community affairs, home and hobbies and personal care. The total CDR score provides the stage of disease severity (0 = Normal to 3 = Severe dementia). The CDR Sum of Boxes (SOB) was calculated by summing each of the domain box scores; ranging from 0 to 18 with higher scores representing greater cognitive impairment. Inter-rater reliability for this measure has been reported as k = 0.53–0.80 [17]. This measure was used to assess whether dementia was associated with change in QoL scores over time.

Patient and public involvement

People with dementia and their family carers were involved throughout the research process though a study specific dementia advisory group, including designing the study, interpreting findings, and helping to disseminate the intervention and findings.

Analysis

Summary statistics were generated on demographic information for the person with dementia and family carer. Means and standard deviations were reported for continuous data, frequencies and percentages were reported for categorical data. Categorical data were dichotomised. Total scores for the C-DEMQOL (and its subscales) and DEMQOL-Proxy were calculated according to their original development guidelines. This included the rules for handling missing data.

To understand how QoL changed over time, a repeated measures ANOVA was run for each dependent variable with the following variables entered as co-variates: duration in study (days), baseline dementia severity (CDR SOB), gender of the family carer (male vs female), gender of the person with dementia (male vs female), family carer relationship (spousal vs non-spousal), dementia diagnosis (Alzheimer vs non-Alzheimer dementia), living status (co-resident vs non co-resident), age of the person with dementia and age of the family carer.

Machly’s test was used to determine whether the sphericity assumption could be held. Violations in sphericity were checked, and if Prob>ChiSq was greater than or equal to 0.05, then sphericity was assumed. Modifications of degrees of freedom were made upon detecting a violation in Sphericity. If the epsilon estimate (ε) >0.75, we used Hunh-Feldt correction, if ε<0.75 then the Greenhouse-Geisser correction was used.

Alongside reporting the main effect of time, statistically significant interactions were also reported alongside their effect size (partial eta, ηp2). To assist with the interpretation of these interactions, covariates were entered into appropriate bivariate analysis (t-test, one-way ANOVA), with outcome change scores of the DEMQOL-Proxy and C- DEMOQL (T3-T2 and T2-T1).

Statistical significance was defined as a p value <0.05. All data were analysed in SPSS V.25.

Results

Two-hundred and forty-eight participants provided data on at least two of the three time-points. On average, 426 days (sd = 203.8 (range 95 to 790) passed between T1 and T2, and 141 days (sd = 22.8 (range 94 to 197) between T2 and T3. The average age of the person with dementia was 77.5 (sd = 8.03) and 69.2 (sd = 10.81) for the family carer. The large majority of people with dementia and family carers were White British/European (99.2% and 99.2% respectively). The family carer was most frequently a spouse/partner (n = 197, 79.4%) of the person with dementia, followed by a son/daughter (n = 49, 19.8%), and the remaining were either a friend or other family member (n = 2, 0.8%). By the end of the study, 77.3% (n = 157) of people with dementia were living with their family carer, 12.3% were living independently, and 10.4% (n = 21) were living in a care home. Of those living in a care home, six had moved into care since March 2020. Full demographic data is presented in Table 1.

Table 1

Baseline participant characteristics (n = 248).

	Person with dementia		Carer
	M	SD	M	SD
Age	77.47	8.03	70.08	10.60
	N	%	N	%
Gender
Male	145	58.5	79	31.9
Female	103	41.5	169	68.1
Ethnicity
White British/European	246	99.2	245	98.8
Mixed/ Multiple Ethnic Groups	1	.4	0	0
Black/African/Caribbean/Black British	1	.4	2	0.8
Missing	0	0	1	0.4
Current Marital Status
Currently married	194	78.2	213	85.9
Other marital status (e.g. widow, cohabiting)	54	21.7	35	14
Highest level of education
Less than primary school	1	.4	0	0
Primary school completed	14	5.6	9	3.6
Secondary school completed	101	40.7	80	32.3
Greater than secondary school completed	129	52	159	64.2
Missing	3	1.2	0	0
Currently employed
Yes	7	2.8	49	19.8
No	240	96.8	199	80.2
Missing	1	0.4	0	0
Rurality
Urban	-	-	48	19.4
Suburbs	-	-	109	44.0
Rural	-	-	90	36.3
Missing	-	-	1	0.4
Living status
Non co-resident			91	36.7
Co-resident			157	63.3
Relationship to the person with dementia
Spouse/partner	-	-	197	79.4
Son/Daughter	-	-	49	19.8
Other	-	-	2	0.8
Diagnosis
Alzheimer’s Disease	93	37.5	-	-
Mixed (for all mixed diagnosis)	66	26.6	-	-
Vascular	37	14.9	-	-
Other	49	19.6	-	-
Missing	3	1.2	-	-
CDR
0	0	0	-	-
0.5 (Questionable)	50	20.2	-	-
1.0 (Mild)	106	42.7	-	-
2.0 (Moderate)	73	29.4	-	-
3.0 (Severe)	11	4.4	-	-
Missing	8	3.2	-	-

Change in mean scores at each time point

Timeline and change in mean scores for DEMQOL-Proxy and C-DEMQOL are provided in Figs 1 and 2.

Fig 1

Timeline and change in mean scores (DEMQOL-Proxy).

Fig 2

Timeline and change in mean scores (C-DEMQOL).

DEMQOL-Proxy

A repeated measures ANOVA with a Huynh-Feldt correction showed that mean DEMQOL-Proxy did not differ significantly between time points [F (2.00, 354.00) = 0.61, p = 0.54, ηp2 = 0.003]. Post hoc analysis revealed a small increase in DEMQOL-Proxy scores between T1 and T2 (MD = -0.27, 95% -2.44 to 1.89), and a small decline between T1 and T3 (MD = 0.12, 95%CI = -1.97 to 2.21). Living status (p = 0.02, ηp2 = 0.03), carer gender (p = 0.04, ηp2 = 0.02) and baseline dementia severity (p = 0.04, ηp2 = 0.02) demonstrated a significant effect on DEMQOL-Proxy scores over time.

Male carers were more likely to report an improvement in DEMQOL-Proxy scores (M = 3.14, SD = 13.99) compared to female carers (M = -1.11, SD = 11.84) between T1 and T2 (MD = 4.26, 95%CI = 0.72 to 7.79, p = 0.02). No other variable was significantly associated with change scores, see Table 2 for further information.

Table 2

Bivariate comparisons of DEMQOL-Proxy (change between time-points).

	T2-T1			T3-T2
	Mean	SD	Co-eff (p)	Mean	SD	Co-eff (p)
Living status			T = 1.54 (p = 0.13)			T = -0.32 (p = 0.75)
Non co-resident	1.93	13.80		-0.83	9.22
Co-resident	-0.76	11.94		-0.28	10.01
Carer gender			T = 2.37 (p = 0.02)			T = -1.11 (p = 0.27)
Male	3.14	13.99		-1.63	10.86
Female	-1.11	11.84		0.10	9.36
Severity Baseline (CDR)			F = 0.38 (p = 0.77)			F = 0.86 (p = 0.47)
Questionable	-1.08	12.39		-2.45	10.15
Mild	.81	12.52		-.15	10.10
Moderate	.45	13.12		.80	9.61
Severe	-2.53	13.48		-.56	6.43

C-DEMQOL

A repeated measures ANOVA with a Huynh-Feldt correction showed that mean C-DEMQOL did not differ significantly between time points [F (1.99, 359.23) = 0.82, p = 0.44, ηp2 = 0.005]. Post hoc tests using Bonferroni correction revealed that the C-DEMQOL reduced by an average of 1.98 points by T2 (95%CI = -0.13 to 4.01) and 3.40 points by T3 (95%CI 1.42 to 5.38). There was a non-statistically significant decline in C-DEMQOL scores between T2 and T3 (MD = 1.42, 95%CI = -0.26 to 3.10). Living status (p<0.001, ηp2 = 0.06) and baseline dementia severity (p = 0.002, ηp2 = 0.03) demonstrated a significant effect on C-DEMQOL scores over time.

For baseline dementia severity, having milder severity was a predictor of greater C-DEMQOL decline between T1 and T2 compared to more severe participants (F = 6.45, p<0.001). C-DEMQOL scores were more likely to decline between T1 and T2 in co-resident carers than those that did not (MD = 7.11, 95%CI = 3.53 to 10.69, p <0.001). Dementia severity and living status were not significantly associated with C-DEMQOL change scores between T2 and T3. See Table 3.

Table 3

Bivariate comparisons of C-DEMQOL (change between time-points).

	T2-T1			T3-T2
	M	SD	Co-eff (p)	M	SD	Co-eff (p)
Living status			T = 4.17 (p<0.001)			T = 0.36 (p = 0.72)
Non co-resident	2.98	14.29		-0.02	0.62
Co-resident	-4.13	11.48		-0.06	0.57
Severity Baseline (CDR)			F = 6.45 (p<0.001)			F = 0.50 (p = 0.69)
Questionable	-4.14	13.20		-2.59	8.72
Mild	-4.09	12.40		-1.54	9.14
Moderate	2.41	11.75		-.91	12.45
Severe	7.65	16.14		2.22	6.24

C-DEMQOL subscales

The ‘meeting person needs’ subscale did not significantly differ between time points F (2.00, 366.00) = 1.04, p = 0.36, ηp2 = 0.006]. Post hoc analysis revealed a 0.86-point decline by T2 (95%CI 0.17 to 1.54), but no significant difference between T2 and T3 (MD = 0.34, 95%CI -0.27 to 0.95). Significant interaction effects were detected for relationship status (p = 0.04, ηp2 = 0.02), baseline CDR (p<0.001, ηp2 = 0.06) and living status (p<0.001, ηp2 = 0.10).

A repeated measures ANOVA with a Huynh-Feldt correction showed that the ‘carer wellbeing’ subscale did not significantly differ between time points F (2.00, 369.07) = 0.57, p = 0.57, ηp2 = 0.003]. Post hoc analysis revealed a 0.85-point decline on the subdomain between T1 and T3 (95%CI 0.28 to 1.42), though there were no significant differences between any other timepoints. Significant interaction effects were detected for baseline CDR only (p = 0.009, ηp2 = 0.03).

The ‘patient relationship’ subscale did not significantly differ between time points F (2, 350) = 1.44, p = 0.24, ηp2 = 0.01. Post hoc analysis revealed that there was a statistically significant decline at T2 (MD = 0.67, 95%CI 0.15 to 1.18) but no significant difference between T2 and T3 (MD = 0.13, 95%CI—0.35 to 0.62). There were no interaction effects with any covariates.

A repeated measures ANOVA with a Huynh-Feldt correction highlighted that the ‘confidence in future’ subscale did not significantly differ between time points F (2.00, 364.00) = 0.72, p = 0.49, ηp2 = 0.004. Between T1 and T2 there was a decline of 0.16 points (95%CI -0.45 to 0.76) and between T2 and T3 there was decline of 0.13 points (95%CI -0.46 to 0.72), neither were statistically significant Only living status (p = 0.02, ηp2 = 0.02) had a significant effect on the confidence in future subscale over time.

The ‘feeling supported’ subscale did not significantly differ between time points, F(2.00, 306.00) = 1.24, p = 0.29, ηp2 = 0.008. Scores did not significantly change between T1 and T2 (MD = -0.41, 95% CI -1.20 to 0.38). However, there was a statistically significant 0.86 decline between T2 and T3 (95%CI 0.14 to 1.58). Again, living status had a significant effect on this subscale over time (p = 0.006, ηp2 = 0.03).

Discussion

This study set out to explore the effect of the COVID-19 pandemic and subsequent restrictions on the QoL of a cohort of people with dementia and their family carers. Overall, it is striking that people with dementia and their carers did not report a decline in QoL during the pandemic or in the months following restrictions. However, there was variation in subgroups and our data suggest that family carers co-resident with the person with dementia they care for were particularly strongly affected in terms of having the greatest decrease in QoL.

We observed that the QoL of people with dementia was generally stable over the three time points, but there was an association with carer gender. Bivariate analysis indicated that QoL was more likely to improve for those with male carers between the first and second timepoint. It is unclear why the gender of the carer should affect change of QoL of the person with dementia. Theoretically, it could be attributed to gendered differences between family carers in how they have handled care and support due to the pandemic, with taking charge being seen as a key coping and adjustment process [18] perhaps to the benefit of the person they care for. Alternatively, it could be that female carers, due to their gender would have been more likely [19, 20] to have been delivering more hands-on care before the pandemic, and as such, might have been more physically and emotionally burdened pre-pandemic, compared to their male counterparts, and therefore less likely to experience any improvements in QoL during the pandemic. However, it may also reflect gender differences in reporting, with males adopting a ‘stiff upper lip’ mentality associated with masculinity [21] or over-estimating QoL of the care recipient as a means to boost masculine status [22] and not to admit failure. Further research is needed to understand the influence of masculinity and gender-related coping strategies on the QoL of people with dementia.

For carer QoL, there was not a decline over the study period. Living status and dementia severity were the only factors to have an effect on carer QoL scores within the multivariate model. Bivariate analysis highlighted that co-resident carers and carers who support the least impaired, experienced the greatest decline in QoL. This association was most notable between the first two timepoints.

Cognitive status and co-resident status remained associated with change scores. Initially, it may seem counter-intuitive that greater cognitive impairment may be associated with improving carer QoL from before the pandemic to the first lockdown. However, it is likely that those with higher cognitive function at baseline had the propensity to experience more cognitive decline than those who were already relatively impaired. As such, carer QoL may represent the impact and adjustment of caring for someone with increasingly impaired cognition. The reduction in services and social restrictions during the pandemic will also have meant that for co-resident carers, there would have been increased time spent together, therefore possibly decreasing carers’ time for respite. Additionally, it is likely the lockdown restrictions would have diminished the ability of carers to be able to undertake activities which offer personal meaning, a factor known to influence carer QoL [23, 24] In the C-DEMQOL development, personal freedom and carer independence were seen as an important component of carer QoL [15, 25, 26], which may have been lost as a result of the pandemic restrictions. Even when exploring these associations on the C-DEMQOL subscales, either dementia severity and/or living status consistently demonstrated interaction effects, with the exception of the patient relationship subscale. The persistent negative effect of co-residence over the two phases of the study underscores its importance in carer QoL terms.

Whilst there can be no comparison group with a pandemic, historical data suggest that DEMQOL-Proxy scores are relatively stable over longer durations before the pandemic (18 months; MD = 1.56) [27]. Our data suggest that overall, the pandemic and associated restrictions may have had less of an impact on people’s QoL than perhaps we expected, or possibly that an adaptation process has occurred to a chronic stress, namely living with dementia for the person with the diagnosis and for their carer.

It might also be that the social restrictions associated with the pandemic have been less impactful due to pre-pandemic reduction in social networks and associated impact on QoL [28].

However, at a more granular level there were subscales of the C-DEMQOL that did change between specific timepoints. From the pre-pandemic period to the first lockdown, our data suggest that meeting personal needs and the carer-patient relationship declined. This perhaps highlights the impact of adjusting to relatively recent restrictions in terms of the halting of support services and shielding. During the pandemic, from the first to the second lockdown there was no recovery in these subscales but they did not continue to decline. But in this second phase there were new declines in the C-DEMQOL feeling supported subscales. These may represent longer term effects of the pandemic on carer QoL.

Our findings suggest that services need to proactively identify people with dementia and their carers who are more likely to be struggling due to the pandemic. The need for services to adapt and provide targeted support to more vulnerable groups of carers is of upmost importance.

There are important limitations to this study. First, as an observational study, we are only able to report associations and cannot make causal inferences. Whilst this study took place in the context of COVID-19 there are other possible reasons for changes in the QoL of people with dementia and their carers which were not measured in this study. Second, the sample was composed of predominantly White British and spousal carers, which may limit consideration of changes by ethnic group and in non-spousal caregivers. The sample was also recruited from England and caution is needed generalising findings to other countries where dementia services and support may have been differentially affected by government restrictions. Third, this is an opportunistic study and baseline data were collected at the time of recruitment into TFD, so the time that passed between baseline measurement and the start of the pandemic was variable and substantial. Fourth, QoL of the person with dementia was assessed using an informant report, and not self-report, whilst the two perspectives have high agreement, it is possible the informant report introduces different biases. The DEMQOL-Proxy does however allow us to estimate the QoL of people with dementia across all severity groups, rather than those who just have mild to moderate dementia. Alongside these limitations there are strengths in the size of the group studied, the two assessment time points during the pandemic and the use of well validated quantitative measures of QoL for the person with dementia and the family carer.

This study provides useful insights into the potential impact of the COVID-19 pandemic and associated public health restrictions on the QoL of people with dementia and their family carers. Whilst the nature of the study limits inference, the study provides novel evidence that, at a group level, the QoL of people with dementia remained stable over the pandemic. In contrast, for co-resident family carers there was a consistent decline in QoL through the pandemic. Given their central importance in supporting people with dementia and the negative clinical and economic consequences of carer burnout, our data highlights the importance of effective support services for carers of people with dementia.

4 Aug 2021

PONE-D-21-19534

Covid-19 and the quality of life of people with dementia and their carers – the TFD-C19 Study

PLOS ONE

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Reviewer #2: No

**********

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Reviewer #2: Yes

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5. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: In the manuscript PONE-D-21-19534, the Authors investigated possible changes in quality of life of individuals with dementia and their careers during COVID-19 pandemic. Interestingly, the Authors had the opportunity to assess this psychological component twice, and to compare it with data collected before the pandemic (i.e., the baseline). Results suggested no substantial changes in quality of life in the assessed population. This results are unexpected in some way, but also they might be very interesting: why did not these groups of people report any changes in their quality of life, in a period in which health services were not approachable as well as the rest of populations suffered from psychological distress? This intriguing results might offer some consideration about what the level (maybe very low) of quality of life of these people before the pandemic. Even though this manuscript sounds very interesting, some methodological criticisms (and specifically in terms of statistical analyses) did not allow me to express a positive feedback about it.

Specifically, the Authors performed two independent analyses in which they compared T0 vs T1, and T1 vs T2, without a clear explanation relative to this choice (the Authors reported “due to the temporal differences” as reason to perform two t-tests, but again this is not a clear explanation). I would suggest to use a repeated measure ANOVA in which the comparisons can be performed between the three time points (to, t1 and t2) in the same analysis. If the Authors performed a repeated measure ANOVA, they can introduce demographical information as well as any other factors as covariates. This analysis might sound more in line with the aim of the manuscript (changes in QoL during the pandemic).

My second concern regarded the use of the regression analyses to verify the role of the demographical factors on the main differences. The use of the regression analyses should be carefully considered, because the Authors used demographical information (in other words, no controlled factor) as predictors. Since the nature of their data, a multivariate analyses might be more adapted (as I have previously suggested). Moreover, the use of this analyses was in disagreement with what reported in the limitation of study (linea 299-300): indeed, regression analyses are meant to described inferential relationship. Because of this criticism, the results relative to the role of the demographical components on quality of life cannot be correctly understood.

In revised their paper, I strongly recommend the Authors to:

- clarify the concept of quality of life (lines 34-35), since it represents a crucial point in their work ; moreover in lines 35-37, the Authors reported that the previous studies did not adopt well-validated measurements? And if it is the case, why it should be matter?

- clarify the aim of the study and predictions, at the end of the Introduction;

- improve tables in terms of clarity, avoiding acronyms and underlining significant differences. Also, the order was altered between table 5 and 6;

- use graphs to show the differences between the scores reported across the three time points; also, a graphical representation of the time points in relation to the contextual information might help Readers in understanding the timeline;

- devote more effort in describing the questionnaires used for their research. For example, what dimensions are measured by DEMQOL_Proxy? Is there any information about statistical validity of this questionnaire? The same information should be reported for all the other measurements. Moreover, what is the difference between the DEMQOL_Proxy and the C_DEMQOL? Moreover, when the CDS was administered (t0 or t1)?

- in describing the results, measures relative to the effect size should be reported. Moreover, I encourage the authors to report 95 % CI in their analysis, since no a priori sample size was performed (and this is completely understandable).

- devote more effort in describing the clinical and social implications from their study. Perhaps, people with dementia and their families live a kind of “self-isolation”, which is not so amplified by the pandemic social restriction.

Reviewer #2: This was a nested study within a larger ongoing study to assess changes (initial change due to pandemic and ongoing change during the pandemic) in mainly the quality of life (QoL) of people with dementia and their carers during the pandemic lockdown in England. The study found that there was no overall change in QoL but certain subgroups were associated with changes in QoL subscale items and in overall QoL scores.

The study used validated instruments and and made comparisons with pre-pandemic scores, as well as between two time points during the pandemic, which were strengths of the study, as many COVID-19 studies on dementia wellbeing are cross sectional in design.

The article is clearly written and presented. Limitations were adequately described.

**********

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Reviewer #1: No

Reviewer #2: No

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

==============================

Please submit your revised manuscript by January, 2022. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

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If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Stephen D. Ginsberg, Ph.D.

Section Editor

PLOS ONE

8 Dec 2021

Amendment requested Changed made

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Thank you for this, we have amended the format to follow PLOS ONE style requirements

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The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified. Thank you in terms of data sharing, Consent was not obtained from participants to share data online. Data will be made available upon reasonable request to the corresponding author

Specifically, the Authors performed two independent analyses in which they compared T0 vs T1, and T1 vs T2, without a clear explanation relative to this choice (the Authors reported “due to the temporal differences” as reason to perform two t-tests, but again this is not a clear explanation). I would suggest to use a repeated measure ANOVA in which the comparisons can be performed between the three time points (to, t1 and t2) in the same analysis. If the Authors performed a repeated measure ANOVA, they can introduce demographical information as well as any other factors as covariates. This analysis might sound more in line with the aim of the manuscript (changes in QoL during the pandemic) Thank you for this useful suggestion. In a major revision we have amended the analyses following the reviewers recommendations. This is detailed in methods (ln 140-167) and findings.

Summary statistics were generated on demographic information for the person with dementia and family carer. Means and standard deviations were reported for continuous data, frequencies and percentages were reported for categorical data. Categorical data were dichotomised. Total scores for the C-DEMQOL (and its subscales) and DEMQOL-Proxy were calculated according to their original development guidelines. This included the rules for handling missing data.

To understand how QoL changed over time, a repeated measures ANOVA was run for each dependent variable with the following variables entered as co-variates: duration in study (days), baseline dementia severity (CDR SOB), sex of the family carer (male vs female), sex of the person with dementia (male vs female), family carer relationship (spousal vs non-spousal), dementia diagnosis (Alzheimer vs non-Alzheimer dementia), living status (co-resident vs non co-resident), age of the person with dementia and age of the family carer.

Machly’s test was used to determine whether the sphericity assumption could be held. Violations in sphericity were checked, and if Prob>ChiSq was greater than or equal to 0.05, then sphericity was assumed. Modifications of degrees of freedom were made upon detecting a violation in Sphericity. If the epsilon estimate (ε) >0.75, we used Hunh-Feldt correction, if ε<0.75 then the Greenhouse-Geisser correction was used.

Alongside reporting the main effect of time, statistically significant interactions were also reported alongside their effect size (partial eta, ηp2). To assist with the interpretation of these interactions, covariates were entered into appropriate bivariate analysis (t-test, one-way ANOVA), with outcome change scores of the DEMQOL-Proxy and C- DEMOQL (T3-T2 and T2-T1).

My second concern regarded the use of the regression analyses to verify the role of the demographical factors on the main differences. The use of the regression analyses should be carefully considered, because the Authors used demographical information (in other words, no controlled factor) as predictors. Since the nature of their data, a multivariate analyses might be more adapted (as I have previously suggested). Moreover, the use of this analyses was in disagreement with what reported in the limitation of study (linea 299-300): indeed, regression analyses are meant to described inferential relationship. Because of this criticism, the results relative to the role of the demographical components on quality of life cannot be correctly understood. Thank you again. We have amended the analyses (ln 140-167) to follow the reviewers recommendations. This is detailed in methods and findings.

Clarify the concept of quality of life (lines 34-35), since it represents a crucial point in their work ; moreover in lines 35-37, the Authors reported that the previous studies did not adopt well-validated measurements? And if it is the case, why it should be matter? Thank you for this point, we have added in a definition of quality of life.

QoL can be defined as the subjective assessment of the position of the individual in their life, in the context to their culture and value system, relating to their goals, expectations and concerns, impacted by their physical and psychological health, level of independence, and social relationships (10). (Ln 37-40)

We have also amended the text to make clearer that there is a need for condition-specific measures of quality in life in dementia, rather than there being a problem with validated measures per se

Living with, or caring for somebody with dementia impacts upon all of the factors known to affect QoL, it is likely that Covid-19 and associated restrictions may have been more impactful for this group of people. There is therefore a need to measure the impact of Covid-19, using condition-specific measures of QoL, which are tailored to the challenges and realities of daily life with dementia. (Ln 40-44)

Clarify the aim of the study and predictions, at the end of the Introduction; Thank you for this point, the study aim has been added

Our study aim was to understand how COVID-19 had affected the QoL, wellbeing, and care of people with dementia and their family carers. (Ln 56-57)

Improve tables in terms of clarity, avoiding acronyms and underlining significant differences. Also, the order was altered between table 5 and 6; All tables have been improved in terms of clarity and the order is correct

Use graphs to show the differences between the scores reported across the three time points; also, a graphical representation of the time points in relation to the contextual information might help Readers in understanding the timeline; This information has been added into the manuscript and is shown in Fig 1 and Fig 2.

Devote more effort in describing the questionnaires used for their research. For example, what dimensions are measured by DEMQOL_Proxy? Is there any information about statistical validity of this questionnaire? The same information should be reported for all the other measurements. Moreover, what is the difference between the DEMQOL_Proxy and the C_DEMQOL?

Moreover, when the CDR was administered (t0 or t1)?

Thank you for this point, the CDR was administered at all time points. The text has been amended to make clear that all measures were used at each time point, and also the provide more information on each of the measures – eg domains and psychometric properties.(Ln 104-132)

The difference between DEMQOL-Proxy and C-DEMQOL has been made clear in the next; namely that DEMQOL-Proxy is a proxy measure of QoL in the person with dementia (as reported by carer) and C-DEMQOL is a self-report of QoL in family carers of people with dementia (Ln 128)

In describing the results, measures relative to the effect size should be reported. Moreover, I encourage the authors to report 95 % CI in their analysis, since no a priori sample size was performed (and this is completely understandable).

Thank you for this point, this has been amended

Devote more effort in describing the clinical and social implications from their study. Perhaps, people with dementia and their families live a kind of “self-isolation”, which is not so amplified by the pandemic social restriction Thank you for this suggestions, we have expanded on this point within the manuscript (Ln 319-435)

It might also be that the social restrictions associated with the pandemic have been less impactful due to pre-pandemic reduction in social networks and associated impact on QoL (29).

However, at a more granular level there were subscales of the C-DEMQOL that did change between specific timepoints. From the pre-pandemic period to the first lockdown, our data suggest that meeting personal needs and the carer-patient relationship significantly declined. This perhaps highlights the impact of adjusting to relatively recent restrictions in terms of the halting of support services and shielding. During the pandemic, from the first to the second lockdown there was no recovery in these subscales but they did not continue to decline. But in this second phase there were new declines in the C-DEMQOL feeling supported subscales. These may represent longer term effects of the pandemic on carer QoL.

Our findings suggest that services need to proactively identify people with dementia and their carers who are more likely to be struggling due to the pandemic. The need for services to adapt and provide targeted support to more vulnerable groups of carers is of upmost importance. (Ln 419-435)

Submitted filename: response to reviewers.docx

Click here for additional data file.

14 Dec 2021

PONE-D-21-19534R1Covid-19 and the quality of life of people with dementia and their carers – the TFD-C19 StudyPLOS ONE

Dear Dr. Daley,

Thank you for resubmitting your work to PLOS ONE. Please make the corrections posed by Reviewer #1 so I can render a decision on this manuscript.

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: Here, I reported my review about the revised version of the article PONE-D-21-19534R1, entitled "Covid-19 and the quality of life of people with dementia and their carers – the TFD-C19 Study". The Authors made a remarkable work in revising the manuscript, especially in the statistical and result sections.

I have only one main concern, that regards the CDR and SF-DEM questionnaires. Indeed, in the revised version of the manuscript, I was not able to find the data about CDR and SF-DEM. Indeed, only the results relative to the QoL – related questionnaires were clearly reported in the Results; so that, the Authors should clarify this point. Also, figures for these two questionnaires may be used to show the scores in the different time points.

Minor points:

• Abstract seemed to be too long, and not in line with the Journal’s style.

• CDR and SF-DEM should not be described along the two QoL – related questionnaires (i.e., the main outcomes of the study) in the Methods, because they assessed two different components.

• Data about the two QoL-related questionnaire would be shown in different figures, since they were related to different scores, with different minimum/maximum, as well as to two different components. Also, the Authors should devote more effort in describing figures in the captions. Such as: “In Figure X, mean (bar) and standard deviation (vertical line) about the mean score (y-axis) registered in thee time point (T0 = before the pandemic; T1 = after XX months after the pandemic; and T2 = XX) at the XXX questionnaire is shown”.

• Pag. 14, lines 270-272: this sentence seemed to be not entirely clear; please, rephrase it.

• In the Discussion, terms like “significantly different” should be avoided.

• I am not a native speaker, but I am wondering if gender rather than sex may be more appropriate as label in the manuscript, such as "carer sex" may be "carer gender".

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

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Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: No

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Please submit your revised manuscript by Jan 28 2022 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: https://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols. Additionally, PLOS ONE offers an option for publishing peer-reviewed Lab Protocol articles, which describe protocols hosted on protocols.io. Read more information on sharing protocols at https://plos.org/protocols?utm_medium=editorial-email&utm_source=authorletters&utm_campaign=protocols.

We look forward to receiving your revised manuscript.

Kind regards,

Stephen D. Ginsberg, Ph.D.

Section Editor

PLOS ONE

22 Dec 2021

Amendment requested Changed made

I have only one main concern, that regards the CDR and SF-DEM questionnaires. Indeed, in the revised version of the manuscript, I was not able to find the data about CDR and SF-DEM. Indeed, only the results relative to the QoL – related questionnaires were clearly reported in the Results; so that, the Authors should clarify this point. Thank you for this very helpful suggestion.

We have removed all of the text related to the SF-DEM (ln 119-124) from the manuscript as you rightly point out it, it is not reflected in the aims or results of the study

We have however kept in the text related to the CDR, as the baseline CDR measurement was used to assess whether dementia severity was associated with change in QoL scores over time. This is also reported in the results section in Table 1: Baseline participant characteristics (n=248)

However, we have moved the CDR related text to the end of the measure section. We have also made the purpose of the using the CDR clearer (as below):

This measure was used to assess whether dementia severity was associated with change in QoL scores over time (ln 140-141)

Also, figures for these two questionnaires may be used to show the scores in the different time points. We have deleted the original Figure 1 (timescales) and replaced two condensed figures. The first (F1) for C-DEMQOL-Proxy with dates and change in mean scores, and the second (F2) for C-DEMQOL with dates and change in mean scores

Abstract seemed to be too long, and not in line with the Journal’s style. We have reviewed the journal’s guidance on abstracts (namely 300 words, explain how study was done, summarise most important results and their significance)

The abstract was 306 words, and we have now reduced this to 300 words. We believe that the abstract does follow the journal’s guidance.

CDR and SF-DEM should not be described along the two QoL – related questionnaires (i.e., the main outcomes of the study) in the Methods, because they assessed two different components. As discussed above, we have removed the SF-DEM and have altered the text on the CDR

Data about the two QoL-related questionnaire would be shown in different figures, since they were related to different scores, with different minimum/maximum, as well as to two different components. Also, the Authors should devote more effort in describing figures in the captions. Such as: “In Figure X, mean (bar) and standard deviation (vertical line) about the mean score (y-axis) registered in thee time point (T0 = before the pandemic; T1 = after XX months after the pandemic; and T2 = XX) at the XXX questionnaire is shown We have amended these two figures (F1, F2) as requested.

Pag. 14, lines 270-272: this sentence seemed to be not entirely clear; please, rephrase it. Our apologies for this. We have re-worded as follows:

Between T1 and T2 there was a decline of 0.16 points (95%CI -0.45 to 0.76) and between T2 and T3 there was decline of 0.13 points (95%CI -0.46 to 0.72), neither were statistically significant (ln 260-262)

In the Discussion, terms like “significantly different” should be avoided.

We have removed this term throughout the discussion.

I am not a native speaker, but I am wondering if gender rather than sex may be more appropriate as label in the manuscript, such as "carer sex" may be "carer gender".

Thank you for highlighting this point, we have changed this term throughout the manuscript

Submitted filename: response to reviewers.docx

Click here for additional data file.

27 Dec 2021

Covid-19 and the quality of life of people with dementia and their carers – the TFD-C19 Study

PONE-D-21-19534R2

Dear Dr. Daley,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

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Kind regards,

Stephen D. Ginsberg, Ph.D.

Section Editor

PLOS ONE

6 Jan 2022

PONE-D-21-19534R2

Covid-19 and the quality of life of people with dementia and their carers – the TFD-C19 Study

Dear Dr. Daley:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

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Thank you for submitting your work to PLOS ONE and supporting open access.

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on behalf of

Dr. Stephen D. Ginsberg

Section Editor

PLOS ONE