Association between grip strength and anthropometric characteristics in the community-dwelling elderly population in Taiwan.

BACKGROUND: Sarcopenia and muscle weakness in elderly are contributed burden of public health and impact on quality of life. Weak grip strength was key role in diagnosis of sarcopenia and reported increased mortality, function declined in elderly. This study evaluated the association between GS and each common anthropometric characteristic in community-dwelling elderly. DESIGN AND
METHOD: From 2017 to 2019, we conducted a community-based health survey among the elderly in Chiayi county, Taiwan. Participants were 65 years old or older, and total of 3,739 elderly subjects (1,600 males and 2,139 females) with a mean age of 76 years (range 65-85 years old) were recruited. General demographic data and lifestyle patterns were measured using a standard questionnaire. Anthropometric characteristics such as body height, body weight, body mass index (BMI), body waist and hip circumference, and body fat were measured by standard methods. GS was measured using a digital dynamometers (TKK5101) method.
RESULTS: The mean GS was 32.8 ± 7.1 kg for males and 21.6 ± 4.8 kg for females (p < 0.001). For both sexes, elderly subjects with the same body weight but smaller body waist circumference had greater GS. The subjects with the same body waist size but heavier weight had greater GS. Furthermore, after adjusting for age, lifestyles, disease status, and potential anthropometric variable, multivariate regression analyses indicated that BMI was positively associated with GS (for males, beta = 0.310 and for females beta = 0.143, both p < 0.001) and body waist was negatively associated with GS (for males, beta = -0.108, p < 0.001; for females, beta = -0.030, p = 0.061).
CONCLUSIONS: This study suggested that old adults with higher waist circumstance had weaker GS. Waist circumstance was negatively associated with GS, body weight was positively associated with GS in contrast. It may implies that central obesity was more important than overweight for GS in elderly.

Introduction

Global ageing is a phenomenon because of declining fertility and increasing life expectancies [1]. Sarcopenia is an age-related pathophysiological process of skeletal muscle loss and muscle strength [2]. The prevalence of sarcopenia is from 6.9% to 63% among different populations and countries [3]. Sarcopenia and muscle weakness are risk factors for physical disability, falls and mortality [4, 5]. Thus, it is not only an important public health issue but also a clinical issue among the elderly. Several causes of sarcopenia include reduction of testosterone and estrogen due to age [6], decline of physical activity [7] and increased insulin resistance with ageing [8].

Grip strength (GS) and gait speed are measures that detect muscle function and are diagnostic criteria for sarcopenia according to the definition of the European Working Group on Sarcopenia in Older People [9]. Nevertheless, GS is a more common, effective, quick and easy method for evaluating the muscle strength [10, 11]. It is also a good predictor of function and disability among the elderly. Good GS is a protective factor for frailty and disability among elderly population [12].

Anthropometric parameters, such as body height (BH), body weight (BW), body waist circumference (WC), body hip circumference (HIP), body fat and body mass index (BMI) are easy methods to evaluate body composition. There have been several studies that reported the relationship between anthropometric parameters and GS among Asian, European and American populations [13-17]. Body waist is proportional to central adiposity, which is associated with insulin resistance, morbidity and mortality. A previous report suggested that the prevalence of sarcopenia among the elderly was lower among those with waist circumference-defined abdominal obesity than those without abdominal obesity [18]. But the central obesity was proven to negatively associate with sarcopenia recently [19]. Hence, the association between GS and body waist in older adults are not clear.

As a rapid ageing society in Taiwan, few studies have investigated the association between GS and anthropometric parameters [20, 21]. This study aimed to demonstrate the epidemiological characteristics of associations between in the GS and each common anthropometric characteristic in community-dwelling older people. Moreover, it examined that whether GS was negatively corrected central obesity and which anthropometric characteristic is potentially the most important correlated to GS.

Materials and methods

Study population

From 2017 to 2019, we conducted a series of community-based health surveys of the middle-aged and elderly populations in Chiayi, Taiwan. People aged 65 years or older and lived in Chiayi county were invited to participate in the survey. A survey has been conducted in Chiayi county every 3 years. A total of 3,739 elderly subjects (1,600 males and 2,139 females) with a mean age of 76 years (range 65–85 years old) participated in the study (S2 File). The inclusion criteria for this study were elderly, aged 65–85 years, and without infection or acute disorders within the previous three weeks.

Questionnaire

General demographic data and lifestyle patterns (including dietary pattern, habit of smoking and alcohol intake) were measured using a standard structured questionnaire (as S1 File). Disease status, such as cardiovascular disease (CVD), cerebrovascular disease (CVA), hypertension, dyslipidemia, diabetes mellitus (DM), chronic kidney disease (CKD), and current medications, was also recorded from the study population.

Anthropometric measurements

Anthropometric characteristics such as BH, BW, WC, HIP and body fat were measured using standard methods. We had trained our staffs before survey conduction. All anthropometric measures, including BH, BW, WC, HIP and body fat, reach the inter-observer variation less than 5% and intra-observer variation around 3–5%. Participants were barefoot and wore light indoor clothing. BH was recorded to the nearest 0.5 cm using a stadiometer. BW was measured to an accuracy of 0.1 kg using a standard beam balance scale (TBF-410, Tanita Corp., Tokyo, Japan). Body fat was measured using a segmental body composition analyser (TBF-410, Tanita Corp., Tokyo, Japan). WC was measured to the nearest 0.1 cm at the midpoint between the margin of the last rib and the iliac crest of the ilium. HIP was measured at the widest part of the pelvic region. We calculated the BMI as BW (kg) divided by the square of height (m2) and calculated the waist-to-hip ratio (WHR) as WC (cm) divided by the HIP (cm).

GS measurement

GS was measured using a digital dynamometers (TKK5101) method, which is a tool with an adjustable grip span, ranging from 3.5 to 7 cm and weighing from 5 to 100 kg with minimal difference around 0.1 kg [22]. All the participants were in a sitting position with fully extended elbows [23]. Then, we measured GS on the dominant hand after 2–3 minutes of resting. Two GS measurements were recorded, and the mean value was used for analyses. For grip strength, the inter-observer variation was less than 5% and intra-observer variation was around 3%, and the standard error mean was about 0.2 ~ 0.3.

The definition of normal GS according to European Working Group on Sarcopenia in Older People (EWGSOP) was ≥ 30kg in the male and ≥ 20 kg in the female. Weak GS was defined as GS < 30 kg in the male and GS < 20 kg in the female [9].

Approval of the IRB

All participants provided written informed consent and agreed to provide their general demographic data, questionnaire answers, anthropometric data and blood samples for the study. The institutional review board of Tri-service General Hospital approved the study (Number: TSGHIRB-1-108-05-073).

Statistical methods

We used SPSS ver-22 (IBM Corporation, New York, NY) to conduct all statistical analyses. We analysed the sample means and SDs of continuous variables, such as anthropometric measures and GS. The Mann–Whitney U test was used to compare the differences between groups. The Kruskal–Wallis H test and post hoc test were used for comparisons of subgroups and to compare more than three groups. Categorical variables were described by number and percentages. A Chi-squared test was used to compare the differences among two or more groups. Spearman’s rank correlation coefficient was used to compare variables. We used multivariate regression analyses to examine the association between anthropometrics variables and grip strength. A two-tailed p value of less than 0.05 was considered statistically significant.

Results

In this present study, Tables 1 and 2 shows the general characteristics of all participants with gender specifications. Male had heavier body weight (65.8 ± 10.1 kg in males and 57.1 ± 9.4 kg in females, p < 0.001) and larger body waist size (88.4 ± 9.1 cm in males and 83.1 ± 9.3 cm in females, respectively, p < 0.001). The body hip was similar between males and females (95.0 ± 6.5 cm in males and 95.6 ± 7.6 cm in females, p > 0.05). Other anthropometric data, including body height and WHR, were significantly greater in males. However, the BMI (kg/m2) was similar between both sexes (24.9 ± 3.4 in males and 25.1 ± 3.8 in females, p >0.05). Moreover, females also had higher body fat than males (22.7 ± 6.4 in males and 32.4 ± 7.4 in females, p < 0.001). The GS was higher in males; the mean grip strength was 32.8 ± 7.1 kg for males and 21.6 ± 4.8 kg for females (p < 0.001). The GS showed significantly differently that the elderly with CVA had weak grip strength in male, but no difference in female (p = 0.002 in male and p = 0.522 in female, respectively). In contrast, the GS showed significantly differently that the elderly with DM had weak grip strength in female, but not in male (p = 0.650 in male and p = 0.05 in female, respectively). The elderly with CVD also demonstrated weaken GS in both genders, although no significant in male (p = 0.142 in male and p = 0.029 in female, respectively). And the elderly with behaviour of alcohol drinking showed significant higher GS in both genders (p = 0.032 in male and p = 0.017 in female, respectively).

Table 1

General characteristics and grip strength among male elderly population (n = 1,600).

Variables	Grips Strength						p-value
	Normal(GS ≥30 kg)			Weak (GS <30 kg)
	(n = 1,061)			(n = 539)
	Mean	±	SD	Mean	±	SD
Age (years)†	71.5±5.2			76.7±6.1			<0.001***
Body height (cm)	163.8±5.7			159.6±5.8			<0.001***
Body weight (kg)	67.7±9.8			61.9±9.7			<0.001***
BMI (kg/m2)	25.2±3.3			24.3±3.5			<0.001***
Body waist (cm)	88.9±8.9			87.3±9.3			0.001**
Body hip (cm)	95.76.3			93.7±6.6			<0.001***
WHR	0.9±0.1			0.9±0.1			0.465
Body fat (%)	23.0±6.2			22.0±6.8			0.003**
Grips strength (kg)	36.7±5.0			25.2±3.6			<0.001***
Chronic disease‡	(n)		(%)	(n)		(%)
CVD	157		14.8	95		17.6	0.142
CVA	30		2.8	32		5.9	0.002**
Hypertension	452		42.6	239		44.3	0.507
Dyslipidemia	156		14.7	63		11.7	0.097
DM	218		20.5	116		21.5	0.650
CKD	36		3.4	29		5.4	0.057
Behavior status	(n)		(%)	(n)		(%)
Smoking	143		13.5	70		13.0	0.785
Alcohol drinking	199		18.8	78		14.5	0.032*

Abbreviations: BMI, Body mass index; WHR: Body waist to hip ratio; CVD, Cardiovascular disease; CVA, Cerebrovascular disease; DM, Diabetes mellitus; CKD, Chronic kidney disease.

† t test was compared with grip strength normal and grip strength weak among characteristics of anthropometry and grip strength; ***p<0.001, **p<0.01, *p<0.05.

‡ chi-square test was compared with grip strength normal and grip strength weak among characteristics of behavior status and chronic diseases; ***p<0.001, **p<0.01, *p<0.05.

Table 2

General characteristics and grip strength among female elderly population (n = 2,139).

Variables	Grips Strength						p-value
	Normal (GS ≥30 kg)			Weak (GS <20 kg)
	(n = 1,377)			(n = 762)
	Mean	±	SD	Mean	±	SD
Age (years)†	71.3±5.3			75.2±6.2			<0.001***
Body height (cm)	152.0±5.4			148.7±5.6			<0.001***
Body weight (kg)	58.5±9.2			54.6±9.4			<0.001***
BMI(kg/m2)	25.3±3.8			24.7±4.0			<0.001***
Body waist (cm)	83.4±9.2			82.7±9.5			0.133
Body hip (cm)	96.2±7.2			94.6±8.1			<0.001***
WHR	0.9±0.1			0.9±0.1			0.004**
Body fat (%)	32.9±7.2			31.4±7.6			<0.001***
Grips strength (kg)	24.4±3.3			16.6±2.5			<0.001***
Chronic disease‡	(n)		(%)	(n)		(%)
CVD	190		13.8	132		17.3	0.029*
CVA	25		1.8	11		1.4	0.522
Hypertension	593		43.1	358		47.0	0.081
Dyslipidemia	220		16.0	117		15.4	0.705
DM	255		18.5	168		22.0	0.050*
CKD	34		2.5	18		2.4	0.878
Behavior status	(n)		(%)	(n)		(%)
Smoking	13		0.9	6		0.8	0.711
Alcohol drinking	38		2.8	9		1.2	0.017*

Abbreviations: BMI, Body mass index; WHR: Body waist to hip ratio; CVD, Cardiovascular disease; CVA, Cerebrovascular disease; DM, Diabetes mellitus; CKD, Chronic kidney disease.

† t test was compared with grip strength normal and grip strength weak among characteristics of anthropometry and grip strength; ***p<0.001, **p<0.01, *p<0.05.

‡ chi-square test was compared with grip strength normal and grip strength weak among characteristics of behavior status and chronic diseases; ***p<0.001, **p<0.01, *p<0.05.

Table 3 shows Spearman’s correlation coefficients between GS and anthropometric variables. Age was negatively correlated to GS in both sexes. BH, BW, BMI, WC, HIP and body fat were all significantly positively correlated with GS (p < 0.001) in both sexes. Compared with other anthropometric measures, only WHR showed a negative correlation but the difference was only statistical significance in female (r = −0.013, p = 0.613 in males and r = −0.047, p = 0.030 in females).

Table 3

Spearman correlation between grip strength and anthropometric variables among elderly population with gender specifications.

	Male(n = 1,600)		Female(n = 2,139)
	coefficient	p-value	coefficient	p-value
Age (years)	-0.458	<0.001***	-0.364	<0.001***
Body height (cm)	0.415	<0.001***	0.348	<0.001***
Body weight (kg)	0.345	<0.001***	0.284	<0.001***
BMI (kg/m2)	0.177	<0.001***	0.138	<0.001***
Body waist (cm)	0.130	<0.001***	0.083	<0.001***
Body hip (cm)	0.218	<0.001***	0.178	<0.001***
WHR	-0.013	0.613	-0.047	0.030*
Body fat (%)	0.111	<0.001***	0.152	<0.001***

Abbreviations: BMI, Body mass index; WHR: Body waist to hip ratio.

Spearman correlation was used for the association between grip strength and anthropometric variables ***p<0.001, **p<0.01

*p<0.05.

Table 4 summarises the distribution of GS among the tertile subgroups of WC and BW in both sexes. We divided WC results into three subgroups; i.e. smallest body waist (WC1), moderate body waist (WC2) and largest body waist (WC3). The BW results were also divided into three groups: lowest body weight (BW1), moderate body weight (BW2) and highest body weight (BW3). After bivariate analyses, the highest GS was found in the elderly with the highest BW and smallest WC in both sexes [a Kruskal–Wallis H test and post hoc test revealed a significant difference (p < 0.05) for different groups in both sexes]. The lowest GS was found in the elderly with the lowest BW and largest WC [a Kruskal–Wallis H test and post hoc test revealed a significant difference (p < 0.05) for different groups in both sexes].

Table 4

Grip strength distribution (Mean ± SD) among elderly population with classification by body weight and body waist with gender specification.

Variables	Body waist (cm)			ANOVA†	Post Hoc Test
	WC1	WC2	WC3
Male	<84.5 cm	84.5–92.0 cm	>92 cm
(n = 1,600)Δ	(n = 531)	(n = 535)	(n = 534)
WT1 (n = 534)	30.3±6.3	28.7±6.2	29.0±6.6	F = 3.49*	T1>T2
WT2 (n = 534)	35.2±6.6	32.7±6.2	31.3±6.8	F = 12.24***	T1>T2,T1>T3
WT3 (n = 532)	38.6±7.1	37.4±7.7	34.9±7.2	F = 6.38**	T1>T2,T2>T3
Female	<79 cm	79–87 cm	>87 cm
(n = 2139)★	(n = 698)	(n = 711)	(n = 730)
WT1 (n = 716)	20.1±4.3	19.9±4.3	18.4±3.6	F = 4.24*	T1>T3
WT2 (n = 718)	22.7±4.3	21.8±4.2	20.8±5.0	F = 8.01***	T1>T3,T2>T3
WT3 (n = 705)	24.2±4.4	23.6±5.4	22.9±5.0	F = 1.63

Abbreviations: WT1, body weight (kg) tertile 1 (lowest); WT2, body weight (kg) tertile 2; WT3, body weight (kg) tertile 3 (highest); WC1, body waist (cm) tertile 1 (lowest); WC2: body waist (cm) tertile 2; WC3, body waist (cm) tertile 3 (highest). T1, body waist (cm) tertile 1 (lowest);T2: body waist (cm) tertile 2; T3, body waist(cm) tertile 3(highest).

† ANOVA F test was to compare these three body waist tertile subgroups of population in grip strength among each body weight tertile specifications

***p<0.001

**p<0.01

*p<0.05.

ΔThe cut-off values were 61.2 kg between BW1 and BW2, and 69.1 kg between BW2 and BW3 in male.

★The cut-off values were 52.7 kg between BW1 and BW2, and 60.6 kg between BW2 and BW3 in female.

Table 5 shows the results of multivariate regression analyses for anthropometric variables and GS. In Model I, after adjusting for age, lifestyles, and disease status (CVD, CVA, hypertension, dyslipidemia, DM, and CKD), the regression coefficient and standard error showed a positive result for all anthropometric variables (except WHR). However, after adjusting for potential anthropometric variables, the body waist was negatively associated with GS in both sexes (the coefficient was −0.108 with p < 0.001 in males and −0.030 with p = 0.061 in females).

Table 5

Multivariate regression analysis for anthropometric variables on grip strength with gender specifications.

Independent variables	Model I†			Model II‡
	β	se β	p-value	β	se β	p-value
Male (n = 1,600)
Body height (cm)	0.408	0.025	<0.001***	0.375	0.026	<0.001***
Body weight (kg)	0.198	0.015	<0.001***	0.365	0.030	<0.001***
BMI (kg/m2)	0.246	0.048	<0.001***	0.310	0.055	<0.001***
Body waist (cm)	0.106	0.018	<0.001***	-0.108	0.031	<0.001***
Body hip (cm)	0.207	0.024	<0.001***	-0.041	0.040	0.296
WHR	1.463	2.724	0.666	-7.489	2.854	0.009**
Body fat (%)	0.039	0.025	0.098	-0.089	0.035	0.011*
Female (n = 2,139)
Body height (cm)	0.236	0.017	<0.001***	0.225	0.017	<0.001***
Body weight (kg)	0.121	0.010	<0.001***	0.219	0.020	<0.001***
BMI (kg/m2)	0.136	0.026	<0.001***	0.143	0.027	<0.001***
Body waist (cm)	0.055	0.011	<0.001***	-0.030	0.016	0.061
Body hip (cm)	0.086	0.013	<0.001***	-0.044	0.023	0.056
WHR	0.975	1.530	0.521	-1.085	1.511	0.473
Body fat (%)	0.061	0.013	<0.001***	0.016	0.022	0.479

Abbreviations: β, regression coefficient; se, standard error; BMI, Body mass index; WHR: Body waist to hip ratio.

† Model I: Adjusting for age, smoking, alcohol drinking, and chronic diseases status (cardiovascular disease, cerebrovascular disease, hypertension, dyslipidemia, diabetes mellitus, and chronic kidney disease).

‡ Model II: For body height, body weight, and BMI further adjusting for body waist and body hip; for body waist, body hip and WHR further adjusting for body height and body weight; for body fat further adjusting for BMI and WHR.

Multivariate regression analysis for anthropometric variables on grip strength

***p<0.001

**p<0.01

*p<0.05.

Discussion

In the current ageing society, sarcopenia and physical disability among the elderly population is important that contributed to burden of public health and impact on quality of life [24]. Increasing evidence has shown that there is an increased risk of mortality in individuals with lower GS [18, 25, 26], possible due to cardiovascular and respiratory diseases and cancer [27]. Moreover, lower GS was also shown to be associated with certain non-communicable diseases, such as diabetes [28] or non-alcoholic fatty liver disease [29]. GS seems to be an indispensable biomarker for elderly [30]. Although both of GS and gait speed are key roles to stand for sarcopenia, measurement of GS was relatively easier and safer than gait speed in old adults.

This study was the first large community-observed prospective study to investigate the relationship between anthropometric characteristics and GS among individuals older than 65 years in Taiwan. The GS of elderly was 32.8 ± 7.1 kg in males and 21.6 ± 4.8 kg in females, which was similar to other studies in Asian populations [21, 31, 32]. Ethnic differences were found in GS, and GS was higher in a Western population when compared to an Asian population [33-37]. Not surprisingly, the GS in elderly with CVA had weak grip strength in both sex, but only showed statically significant difference in male. This is possible because poor stroke outcome of activity limitation assessed from the modified Rankin Scale in female compared with male in previous study [38, 39]. A healthcare participant bias might exist in this study that the females with severe CVA cannot attend to our investigation because of bedridden. Interestingly, the elderly with the behaviour of alcohol drinking had the higher GS, and it was consistent with previous published study [40-42]. Although the alcohol use may weaken and waste skeletal muscle [43], but the mechanism for protective factor of GS in elderly with drinking was still unclear [42].

There were some limitations in our community survey study. There was existing bias of false negatives when using questionnaires and questioning for underlying disease. Moreover, participant bias should be considered if those with a disability could not participate in the survey. Hence, we may have overestimated GS. However, our results indicate an association between anthropometric variables and GS among elderly are still reliable. Unlike results reported in other studies, Lee et al. [32] and Günther et al. [34] found that the GS was correlated with height in both sexes, and weight was correlated in males but not in females. Our data showed that GS was significantly correlated with BH, BW and BMI even after adjusting for age. This finding is consistent with the study of Silventoinen et al. [35], although the population in their study was composed of youth. In summary, previous studies produced similar results indicating that GS is inversely correlated with age but showed a positive correlation with height.

Previous study investigated usually demonstrated the univariate association between GS of each anthropometric variable, this study uses WC and BW as variable factor to perform bivariate analyses of GS (as Table 3) in a large community population. Interestingly, we found that elderly subjects with the same BW but smaller WC had greater GS in both sexes with statistical significance even after ANOVA and post hoc analysis. Conversely, elderly subjects with the same WC but heavier weight had greater GS in both sexes. In order to understand which anthropometric file was possibly the most negatively associated with GS, we use multivariate regression with adjusting for the potential factors (as model 2 in Table 4). It reported that GS was only negatively associated with markers of central obesity (Body waist, body hp and WHR), but positively associated body weight. This result was consistent with our previous study that being adequate overweight might be a protective factor in elderly [44]. Compared with overweight, central obesity was harmful for elderly.

Although the importance of GS is unclear in a clinical scenario, GS represents the nutritional profile [45] and physical obesity, and increasing evidence has shown that there is an increased risk of mortality in individuals with lower GS. In the future, a larger cohort study or clinical trial is required to investigate and support the association between waist circumference and grip strength. GS may be an essential parameter not only to evaluate multiple risk factors, such as cardiometabolic or physical disability in clinical scenarios, but also correlated with age and many anthropometric characteristics.

Conclusion

To conclude, our study showed that GS in the elderly Taiwanese population was similar to reports on GS in other Asian groups and was weaker than the GS of Western populations. Using bivariate analysis, we found that GS was lower among those with a larger WC in subjects with the same BW. Moreover, the GS of the elderly was highly correlated with BH, BW and BMI but was inversely associated with waist circumference in both sexes. In other words, elderly subjects with central obese had a weaker GS, which is a crucial factor when predicting muscle weakness among the community-dwelling elderly population in Taiwan.

Chiayi-questionnaire-Eng.

Questionnaire using in the survey.

(PDF)

Click here for additional data file.

All-data-eng.

Basic characteristics and anthropometric data, history of all participants.

(XLS)

Click here for additional data file.

8 Sep 2021

PONE-D-21-24416Association between anthropometric characteristics and grip strength among elderly population in TaiwanPLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. 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: No

Reviewer #2: Yes

**********

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

Reviewer #1: I Don't Know

Reviewer #2: No

**********

3. 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

Reviewer #2: Yes

**********

4. 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

Reviewer #2: No

**********

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: Major comments

I believe the topic of this paper is rather timely and appropriate, as this area of research has been expanding in recent years. However, the justification for the experimental protocol and discussion are very weak.

Table 6

Materials and Methods

Interobserver and intraobserver ICC is also needed in all measurements (Grip strength, body waist circumference, etc.).

Additionally, the Grip strength was very important point in this study, the authors should measured a few times. The test-retest reliability (ICC, SEM and minimal difference) is needed.

Minor comments

Limitation

Although only one limitation was proposed, it was written as some limitations.

It needs to be revised.

Table 1

As the data in Table 2 women, all data in the upper half require “±”.

Reviewer #2: [Peer Review Summary]

All the paragraphs are interesting, but many parts are not fully explained, making them difficult to understand. There are issues with the way the sentences are arranged. Therefore, to understand the claims of this study accurately, to emphasize the novelty and social significance, the structure needs to be revised. For this, you can create a better flow by replacing the context and summarizing what you want to emphasize in each paragraph. I suggest you categorize what you are saying in each section and reconsider the order in which you explain it. There are also grammatical errors such as spelling, definite articles, singular, and plural. Please check it.

---------------

Minor＝None

Major=★

---------------

[Abstract ]

1.Anthropometric is generally recognized as height, weight, body mass index (BMI), body circumference (waist, hips, extremities), sebaceous thickness. However, this study also describes the association between grip strength and medical diseases, so this should be added to the title or modified by changing the title.

★2.Background

The title gives a strong impression that this study focuses on the relationship between grip strength and anthropometric characteristics. However, in the background, the topics of sarcopenia and frailty are discussed. It seems to make it difficult for readers to understand the content. Therefore, if you would like to argue about sarcopenia and frailty, you had better consider as follows: GS and muscle strength, GS and sarcopenia or Frailty, and GS and anthropometric characteristics. These items should be discussed more from the results especially in the discussion section.

3.Design and Method

Please indicate the number of subjects, their age and gender.

4.Results

The number of participants and subject details should be described in Design and Method

[Introduction]

★1.This is the same as the comments in the abstract.

There was a strong impression that this study focuses on the relationship between grip strength and anthropometric characteristics. However, in the background, the topics of sarcopenia and frailty are discussed. It seems to make it difficult for readers to understand the content. Therefore, if you would like to argue about sarcopenia and frailty, you had better consider as follows: GS and muscle strength, GS and sarcopenia or Frailty, and GS and anthropometric characteristics. These items should be debited from the results especially in the discussion section.

2.There should be some kind of conjunction to connect the sentence with the previous sentence as follows: The relationships between sarcopenia, obesity, and central obesity are not well established. This sentence could start with ‘However,….’.

★3.Reference 9 is a research paper on central obesity, sarcopenia, and nutrition. This paper concludes that central obesity and sarcopenia were interrelated with nutritional status in the elderly. However, you state that it is not well established. I would like to know your thoughts or comments on this.

★4.The results and discussion are inadequate for the study; similar comments are in the abstract. It needs to be written more coherently. This study aimed to clearly state the epidemiological characteristics of sarcopenia and frailty, but the results also emphasize the relationship between GS and anthropometric parameters, so I think the overall sentence structure needs to be revised in the abstract.

[Materials and Methods]

1.Study Populations

Please indicate the number of subjects, their age and gender.

2.previous three weeks

Simple question, is there any evidence that it is 3 weeks?

★3.Questionnaire

Association between the results of the questionnaire and the results of the anthropometric measurements should be explained in the Discussion. Everything that you have experimented with must be discussed.

4.There is insufficient information about the equipment used for the measurement. Only the grip strength tester is listed. Please provide information on all devices.

★5.GS measurement

Reference 22, this study examined the relationship between elbow joint angle and grip strength in subjects aged 20-57. Although grip strength is generally measured with the elbow extended. It's unclear about the purpose of measuring it in a sitting position and with the only dominant hand. An explanation or intention for applying this method to the elderly is needed.

6.Statistical methods

I think the grouping cutoff (e.g. normal, weak) should be indicated in the text as well. Also please check the other groupings.

[Results]

★1.I don't think it is necessary here to restate subject details such as age; in Results, you should simply state the results of your analysis.

2.Need to include the results of medical disease risk from blood samples.

3.In the sentence as follows; “compared with other anthropometric measures, only WHR showed a negative correlation, but the difference was without or borderline statistical significance in both sexes (r = -0.013, p = 0.613 in males and r = -0.047, p = 0.030 in females)”. For females, the significance is lower, but it is 0.03. I think you need to modify the explanation method.

4.The reason for Model 1 and Model 2 classification is unclear. I do not understand on what basis the models were classified. I think it would be better to indicate whether the classification was based on controllable factors such as congenital or acquired factors.

[Discussion]

★1.Insufficient consideration of measurement results. As commented in the questionnaire section, everything that has been experimented with should be discussed.

2.In the sentence as follows; “In the current ageing society, sarcopenia and physical disability among the elderly population is becoming increasingly important”. What is important? How is it important? Please explain.

3.In the sentence as follows; “although no obvious and clear mechanism has been discovered”. It is unclear from this what has not been clarified.

★4.In the sentence, as follows; “This study was the first large community-observed prospective study to investigate the relationship between anthropometric characteristics and GS among individuals older than 65 years in Taiwan”. A poor match between title and research content. This is the same as the comments in the abstract.

5.In the sentence as follows; “This result can be explained by the fact that taller individuals also have longer bones, which gives them greater GS”, Reference 32 is a twin study. It shows that GS changes with growth, but I don't think it says that " long bones have stronger GS". It is good to list the literature, but I think this sentence should be deleted or changed to another way of explanation.

★6.In the sentence, as follows; “This study applied simple personal anthropometric profile〜”. What you have shown in this paragraph is a unique result. If you want to emphasize the novelty here, you should include more discussion about this.

[Conclusion]

1.In the sentence as follows; “To conclude, our study showed that GS in the elderly Taiwanese population was similar to reports on GS in other Asian groups and was weaker than the GS of Western populations”. The term "Taiwanese elderly" is very broad, so I think it would be better to change the wording. Also, which report is being compared to be lower than the Western population?

★2.About the sentence as follows; “muscle weakness among elderly population in Taiwan.” It said, it predicts muscle weakness, but in your discussion, you say, "GS is considered an essential parameter in clinical settings to assess multiple risk factors such as cardiovascular and physical disorders." 1 be better to describe not only the prediction of muscle weakness but also the relationship with other parameters.

[Table1,2,3,4]

1.I think it would be better to show the cutoff values for Normal and Weak, and I have made the same comment in Statistical methods.

2.In Tables 2 and 4, there are no asterisks in the tables for p-values. 1A and 1B have asterisks, and there is a supplementary note below the tables saying **p<0.01, *p<0.05. Therefore, I think it should be standardized for all tables.

**********

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Reviewer #1: Yes: Tomohiro Yasuda, PhD

Reviewer #2: No

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8 Oct 2021

no

Submitted filename: Plos-One-Review-Response-20211008.doc

Click here for additional data file.

25 Oct 2021

PONE-D-21-24416R1Association between grip strength and anthropometric characteristics in the community-dwelling elderly population in TaiwanPLOS ONE

Dear Dr. CHU,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

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Kiyoshi Sanada, PhD

Academic Editor

PLOS ONE

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Please review your reference list to ensure that it is complete and correct. If you have cited papers that have been retracted, please include the rationale for doing so in the manuscript text, or remove these references and replace them with relevant current references. Any changes to the reference list should be mentioned in the rebuttal letter that accompanies your revised manuscript. If you need to cite a retracted article, indicate the article’s retracted status in the References list and also include a citation and full reference for the retraction notice.

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Reviewers' comments:

Reviewer's Responses to Questions

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: (No Response)

Reviewer #2: (No Response)

**********

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: Partly

Reviewer #2: Yes

**********

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

Reviewer #1: I Don't Know

Reviewer #2: 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

Reviewer #2: 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

Reviewer #2: 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: >Interobserver and intraobserver ICC is also needed in all measurements (Grip

strength, body waist circumference, etc.).

Additionally, the Grip strength was very important point in this study, the

authors should measured a few times. The test-retest reliability (ICC, SEM and

minimal difference) is needed.

Thank you for your valuable comments. We did our best to train our staff to

reach the inter-observer variation less than 5% and intra-observer variation

around 3-5%.

It should be described in the Materials and Methods and shown to the reader, not just the reviewer.

It is necessary for the reader to judge whether the measurement was performed under appropriate conditions.

Reviewer #2: In my last review, I had asked for a correction regarding the p-value.

In that case, for example, in Table 2, only one part was marked with an asterisk. Therefore, it was suggested that it would be better to unify them.

In this case, using Table 2 as an example, all women are marked with a symbol, while men are not.

The intention of the last review was that unification meant that if you wanted to add a symbol, you would put it on everything, and if not, you would remove it all.

This is a decision based on your thoughts.

Thank you for your consideration.

**********

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.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

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: Yes: Tomohiro Yasuda

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

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.

27 Oct 2021

We have revised and modified our update manuscript to fit reviewers’ comments.

Submitted filename: Plos-One-Review-Response-20211028.doc

Click here for additional data file.

17 Nov 2021

Association between grip strength and anthropometric characteristics in the community-dwelling elderly population in Taiwan

PONE-D-21-24416R2

Dear Dr. CHU,

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.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

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If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. 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.

Kind regards,

Kiyoshi Sanada, PhD

Academic Editor

PLOS ONE

Additional Editor Comments (optional):

Reviewers' comments:

Reviewer's Responses to Questions

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

Reviewer #2: (No Response)

**********

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

Reviewer #2: Yes

**********

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

Reviewer #1: Yes

Reviewer #2: 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

Reviewer #2: 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

Reviewer #2: 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: Thank you for the revision.

I have no additional comments for the author.

I feel that this manuscript is now acceptable for publication.

Reviewer #2: (No Response)

**********

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.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

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: Yes: Tomohiro Yasuda, PhD

Reviewer #2: No

7 Dec 2021

PONE-D-21-24416R2

Association between grip strength and anthropometric characteristics in the community-dwelling elderly population in Taiwan

Dear Dr. Chu:

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.

If we can help with anything else, please email us at plosone@plos.org.

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

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Kiyoshi Sanada

Academic Editor

PLOS ONE