Correlation of long-term medication behaviour self-efficacy with social support and medication knowledge of kidney transplant recipients.

AIM: This study aimed to explore the correlation of long-term medication behaviour self-efficacy with social support and medication knowledge of kidney transplant recipients.
METHODS: A convenient sample of kidney transplant recipients in a general hospital in Guangzhou was recruited from November 2016 to January 2017. Self-reported survey data were provided by the kidney transplant recipients using long-term medication behaviour self-efficacy scale (LTMBSES), perceived social support scale (PSSS) and scale for patient-perceived medication knowledge in medication usage. Descriptive statistics and Spearman's correlation analysis were used for data analysis.
RESULTS: A total of 195 kidney transplant recipients (132 men and 63 women) were recruited for this study. The mean scores of all LTMBSES dimensions, namely personal attitudes, environmental and task-related and behavioural factors, were 32.49 ± 4.34, 60.90 ± 7.56 and 32.32 ± 4.40, respectively. The mean scores of three PSSS dimensions, namely, family, friends and significant others, were 24.91 ± 3.42, 22.71 ± 4.66 and 22.15 ± 4.26, correspondingly. The mean scores of two five-item knowledge subscale dimensions, namely, general and interaction knowledge, were 9.56 ± 1.07 and 13.02 ± 2.67, respectively. Spearman's correlation analysis showed that social support (r s  = 0.232, P < 0.01) and medication knowledge (r s  = 0.352, P < 0.01) were positively associated with long-term medication self-efficacy in the kidney transplant recipients.
CONCLUSION: The levels of long-term medication self-efficacy, perceived social support and medication knowledge of the kidney transplant recipients were high. Social support and medication knowledge were correlated with self-efficacy.

Introduction

Kidney transplantation is the optimal and routine treatment for end-stage renal disease [1]. With the development of surgery, transplantation immunology, organ preservation technology, transplant monitoring methods and the introduction of novel immunosuppressive agents, the number of kidney transplant recipients has increased over the past decades. The survey results of the Global Observatory on Donation and Transplantation have shown that 84,347 kidney transplant cases, which account for 66.59% of all organ transplants cases, were performed in 2015 [2]. The data from the Chinese Scientific Registry of Kidney Transplantation showed that 63,842 kidney transplant cases have been performed from 2007 to 2016 in China [3]. To reduce the incidence of rejection, kidney transplant recipients must take immunosuppressive agents extensively, even for a lifetime [4,5]. However, 28%–52% of kidney transplant recipients are non-adherent to their regimens [6,7], thereby possibly contributing significantly to poor clinic results, such as rejection, graft losses or death [8,9]. Thus, non-adherence is a self-care major issue and represents a key challenge for health professionals [10].

Bandura stated that the ability to exhibit certain behaviours is influenced by the belief that an individual can demonstrate such behaviours; this belief is referred to as self-efficacy, which can be used to stimulate and maintain a healthy behaviour [11]. Self-efficacy refers to an individual's belief and confidence in completing a certain behaviour or skill [12]. It can improve a patient's treatment compliance by promoting an active cooperation with a healthcare provider and by strengthening the self-confidence to recover [13]. High self-efficacy for medication-related behaviours can maintain an adherent behaviour. Furthermore, enhancing self-efficacy of kidney transplant recipients can improve their compliance, thereby preventing chronic rejection and improving the survival rate of recipients [14].

Social support is a self-appraisal of real or perceived social networks of family, friends and organizations and provides emotional, financial or personal assistance when necessary [15]. Social support is important for health preservation. Such support is an essential component for adopting and maintaining self-care measures [16]. Improved social support may increase the life quality of patients [17]. Bandura [18] emphasised that social support can influence self-efficacy and health behaviour. In addition, social support affects the self-efficacy of chronic patients [19].

Social support and recipients' medication knowledge are important factors that affect self-efficacy. A cross-sectional study has analysed the influence of medication knowledge and adherence in 150 patients with chronic diseases; the results showed that a patient's confidence in taking medications is related to the level of medication knowledge [20].

Only a few studies have examined the relationship between self-efficacy, social support and medication knowledge among kidney transplant recipients. Therefore, the present study explored the correlation of long-term medication behaviour self-efficacy with social support and medication knowledge of kidney transplant recipients.

Materials and methods

Participants

This investigation used a cross-sectional design to explore the correlation of long-term medication behaviour self-efficacy with social support and medication knowledge of kidney transplant recipients in a general hospital in Guangzhou from November 2016 to January 2017. A total of 233 kidney transplant recipients who had visited transplant follow-up clinics were recruited using a convenience sampling method. All participants passed the following inclusion criteria: (1) aged 18 years or above, (2) minimum of 3 months post-transplantation, (3) functional kidney graft, (4) can speak and read Chinese and (5) can provide informed consent. Exclusion criteria were set as follows: (1) accepted two or more kidney transplants and (2) accepted two or more kinds of organ transplants.

Measurement

Sociodemographic information (i.e. age, sex, body mass index (BMI), work status, educational level, marital status, medical payment, family income and economic burden), clinical information (i.e. donor type, post-transplant period and complications, rejection and infection after transplantation), self-efficacy, social support and medication knowledge were assessed by using a self-reported scale.

Long-term medication behaviour self-efficacy

Long-term medication behaviour self-efficacy scale (LTMBSES) was adopted to assess the long-term medication behaviour self-efficacy of kidney transplant recipients. The LTMBSES was developed by De Geest et al. [21] on the basis of the theory of self-efficacy. The scale had 27 items and 3 dimensions, namely, personal attitudes, environmental and task-related and behavioural factors. The score for each item ranged from 1 (not at all confident) to 5 (completely confident), thereby obtaining a total score range of 27–135; high scores indicated an improved perception of self-efficacy [22]. The original LTMBSES obtained from original authors was translated into Chinese in the present study. The Cronbach's α coefficient for the LTMBSES and all LTMBSES dimensions were satisfactory (α = 0.977, 0.919, 0.946, 0.919 for LTMBSES, personal attitudes, environmental and task-related and behavioural factors, correspondingly). The test–retest reliability correlation coefficients of LTMBSES, personal attitudes, environmental and task-related and behavioural factors at a two-week interval were 0.780, 0.844, 0.852 and 0.888, respectively. The expert content validity was 0.874.

Social support

Perceived social support scale (PSSS) was used to assess the social support of kidney transplant recipients. This scale was developed by Zimet et al. [23] and has a favourable internal consistency (Cronbach's α = 0.85–0.91). The Chinese version of PSSS was translated by Huang et al. [24]. The scale had 12 items and 3 dimensions, namely, family, friends and significant others. The score for each item ranged from 1 (very strongly disagree) to 7 (very strongly agree); high scores indicated a high perceived social support. The total score ranged from 12 to 84. The level of perceived social support of kidney transplant recipients was determined on the basis of the total score. A total score of 57–84, 29–56 and less than 28 indicated high, medium and low levels of perceived social support, correspondingly. The Cronbach's α of PSSS and its subscales family, friends and significant others were 0.927, 0.910, 0.939 and 0.896, respectively.

Medication knowledge

A five-item knowledge subscale from the scale for patient-perceived knowledge and confidence in medication usage [25] was adopted to assess the patient-perceived medication knowledge of kidney transplant recipients. This scale had two dimensions, namely, general and drug interaction knowledge. The Cronbach's α coefficient of the scale was 0.833. Higher score indicates higher level of medication knowledge.

Ethical considerations

Ethical approval was obtained from the ethics committee of the university and hospital. Voluntary, confidentiality, fair and harmless ethical principles were followed in this study. We explained the purpose, risks and benefits of the experiment to the recipients before they were asked to participate. All patients agreed to participate in the study with a signed written informed consent.

Data collection

Every investigator was trained before conducting this survey. A questionnaire packet and a cover letter containing the description of the study, response confidentiality, consent procedure and investigator's contact details were placed in unsealed envelopes. The unsealed envelopes were distributed to the kidney transplant recipients upon agreeing to participate in this study. The questionnaire was completed independently by the recipients at the follow-up clinic.

Statistical analysis

Original data were inputted into Excel spreadsheet and checked by two research assistants. Statistical analyses were performed using SPSS 20.0. Categorical variables were described as frequency and percentages, and continuous variables were presented as Mean ± SD. Spearman's correlation analysis was conducted to correlate self-efficacy, social support and medication knowledge. In this study, the statistical level of significance was set at P < 0.05 for two sides.

Results

Characteristics of participants

A total of 233 questionnaires were distributed, and 221 were returned, thus indicating a return rate of 94.85%, of which 26 were incomplete and considered invalid. Thus, the final sample comprised of 195 participants. The age range of recipients was 18–73 years with a mean of 42.31 ± 11.31 years. A total of 132 67.69 of the recipients were male. Table 1 summarises the other demographic and clinical characteristics of the 195 kidney transplant recipients.

Table 1

Characteristics of kidney transplant recipients (n = 195).

Variables	n or Mean ± SD	% or Range
Age (years)	42.31 ± 11.31	18–73
Gender
Male	132	67.69
Female	63	32.31
BMI
<18.5	29	14.87
18.5–23.9	132	67.69
24.0–27.9	28	14.36
≥28.0	6	3.08
Employed
Yes	132	67.69
No	63	32.31
Education
Middle school or below	25	12.82
High school or technical secondary school	69	35.38
College degree or above	101	51.80
Marital status
Married	155	79.49
Single/widowed/divorced	40	20.51
Medical payment
By self	10	5.13
Public service or medical insurance	185	94.87
Family income( ¥/month)
≤3000	43	22.05
3000–6000	66	33.85
>6000	86	44.10
Economic burden
No burden	19	9.74
Mild	40	20.51
Moderate	84	43.08
Severe	52	26.67
Donor
Deceased	186	95.38
Living	9	4.62
Duration after RT (year)	5.13 ± 4.92	0.25–19.33
Comorbidity (type)
0	57	29.23
≥1	138	70.77
Rejection episodes
0	182	93.33
≥1	13	6.67
Infection episodes
0	158	81.03
≥1	37	18.97

Long-term medication behaviour self-efficacy

In this study, the LTMBSES total scores of the kidney transplant recipients ranged from 27 to 135, and the mean score was 125.75 ± 15.85. The mean scores of the LTMBSES dimensions, namely, personal attitudes, environmental and task-related and behavioural factors, were 32.49 ± 4.34, 60.90 ± 7.56 and 32.32 ± 4.40, correspondingly (Table 2).

Table 2

LTMBSES scores of kidney transplant recipients.

Variables	Min	Max	Mean ± SD
Personal attitudes	7	35	32.49 ± 4.34
Environmental factors	13	65	60.90 ± 7.56
Task-related and behavioural factors	7	35	32.32 ± 4.40
Total score	27	135	125.75 ± 15.85

Social support

The PSSS total scores of the kidney transplant recipients ranged from 30 to 84, and the mean score was 69.77 ± 10.34. Based on the evaluation criteria of PSSS, kidney transplant recipients’ perceived social support was at either medium or high level, in which 8.72% of the recipients had medium-level social support, and 91.28% had high-level support. The mean scores of the three dimensions, namely, family, friends and significant others, were 24.91 ± 3.42, 22.71 ± 4.66 and 22.15 ± 4.26, respectively; the mean score was higher in family support than in other dimensions (Table 3).

Table 3

PSSS scores of kidney transplant recipients.

Variables	Min	Max	Mean ± SD
Family support	4	28	24.91 ± 3.42
Friends' support	4	28	22.71 ± 4.66
Significant others' support	7	28	22.15 ± 4.26
Total score	30	84	69.77 ± 10.34

Note: PSSS= Perceived Social Support Scale.

Medication knowledge

In this study, the total scores of the five-item knowledge subscale of the kidney transplant recipients ranged from 5 to 25, and the mean score was 22.60 ± 3.31. The mean scores for general and drug interaction knowledge were 9.56 ± 1.07 and 13.02 ± 2.67, respectively (Table 4).

Table 4

Five-item knowledge subscale scores of kidney transplant recipients.

Variables	Min	Max	Mean ± SD
General knowledge	2	10	9.56 ± 1.07
Drug interaction knowledge	3	15	13.02 ± 2.67
Total score	5	25	22.60 ± 3.31

Correlation of long-term medication behaviour self-efficacy with social support and medication knowledge

Spearman's analysis was used to correlate long-term medication behaviour self-efficacy, social support and medication knowledge. Table 5 lists the correlation coefficients among long-term medication behaviour self-efficacy, social support and medication knowledge.

Table 5

Spearman's correlation coefficients among self-efficacy, social support and medication knowledge.

Variables		LTMBSES
		Personal attitudes	Environmental factors	Task-related and behavioural factors	Total score
PSSS	Family's support	0.214a	0.217a	0.184 b	0.206a
	Friends' support	0.201a	0.168 b	0.172b	0.184b
	Significant others' support	0.174b	0.165b	0.109	0.169b
	Total score	0.239a	0.226a	0.189a	0.232a
Five-item knowledge subscale	General knowledge	0.259a	0.246a	0.266a	0.260
	Drug interaction knowledge	0.308a	0.240a	0.390a	0.347a
	Total score	0.317a	0.250a	0.396a	0.352a

Note: LTMBSES = Long-term Medication Behaviour Self-efficacy Scale; PSSS= Perceived Social Support Scale; aP < 0.01, bP < 0.05.

Discussion

Long-term medication behaviour self-efficacy, social support and medication knowledge of kidney transplant recipients are high

In this study, the mean score of long-term medication behaviour self-efficacy was 125.75 ± 15.85, thereby indicating a high level of long-term medication behaviour self-efficacy in the kidney transplant recipients. This result was consistent with the results of prior studies [[26], [27], [28]]. Self-efficacy is an important predictor of behavioural change; a person with high self-efficacy is willing to engage in healthy behaviour [29]. Silva et al. [28] demonstrated that the self-efficacy of kidney transplant recipients is associated with medication compliance. Therefore, healthcare providers should timely evaluate and improve the long-term medication behaviour self-efficacy of kidney transplant recipients.

In this study, the mean score of social support was 69.77 ± 10.34, thus indicating a high perceived social support of the kidney transplant recipients. This result coincided with the previous reports on kidney transplant recipients in China [27,30,31]. Individuals with a high social support have high subjective well-being, life satisfaction and positive emotions, which can positively affect their mental health. In addition, a high social support can reduce the negative impact of stress, thus encouraging an individual to maintain good health. Therefore, healthcare providers should provide recipients with social support, such as information and emotional care. Furthermore, kidney transplant recipients require concern and companionship; thus, family and friends should encourage recipients to accept their condition and maintain an optimistic attitude and positive mood.

For kidney transplant recipients, maintaining a normal renal function is an important health behaviour [32]. They must take immunosuppressive agents extensively; thus, medication knowledge is essential for them. In our study, the score on medication knowledge of the kidney transplant recipients was high. This result indicated that such recipients maintain robust health education about taking medication after transplantation.

Medication knowledge is related to long-term medication behaviour self-efficacy of kidney transplant recipients

Among knowledge, attitude and practice model, knowledge is the basis for establishing positive and correct beliefs, attitudes and behaviours. Similar to patients with other chronic diseases, kidney transplant recipients must acquire medication knowledge and establish correct beliefs and behaviours [33]. In our study, medication knowledge was related to self-efficacy. In particular, kidney transplant recipients with robust medication knowledge had high long-term medication behaviour self-efficacy. This result agrees with Zhang et al.’s [34] research, which found that self-efficacy was related to health knowledge in kidney transplant recipients. Interventions, such as individualized medication education, may be necessary to increase the medication knowledge of kidney transplant recipients.

Social support is related to long-term medication behaviour self-efficacy of kidney transplant recipients

In the present study, social support was found to be related to long-term medication behaviour self-efficacy of kidney transplant recipients. Recipients with high long-term medication behaviour self-efficacy had a high level of social support. Similar results were found in other research. Shao et al. [35] investigated the effect of social support on glycaemic control in type 2 diabetes mellitus and found that self-efficacy is positively correlated with social support, which also affected compliance through self-efficacy. Pugh et al. [36] performed a qualitative study and found that selecting a healthy lifestyle indicates that social support is a facilitator of self-efficacy improvement.

Self-efficacy theory highlights that a high level of social support is the main factor in establishing and developing self-efficacy, and high self-efficacy is beneficial for self-management of transplant recipients [37]. Similar results have appeared in other studies [38,39]. Social support can affect the frequency and duration of individual exposure to a pressure source. For example, recipients with a high level of social support may not be required to work soon after transplantation; thus, these recipients can stay at home and recover. Social support can promote healthy behaviours. For example, a reminder from family members to take medication on time may help improve the medication adherence behaviour of recipients [40]. A high level of social support can provide a patient with various materials that promote a positive mood, thereby improving patients’ self-efficacy. Therefore, healthcare providers must encourage recipients to use their social support system to improve self-efficacy.

Limitation and recommendations

Our study has certain limitations. Firstly, our study was a single-centre cross-sectional survey. Secondly, our study did not explore other factors that affect self-efficacy. Thus, multi-centre, large sample and longitudinal studies of social support, medication knowledge and self-efficacy in kidney transplant recipients are required. Other influencing factors of self-efficacy must be explored in future research.

Conclusion

With the progress of society and the continuous development of medical models, many people have become health-conscious. The results of this study showed that the self-efficacy of kidney transplant recipients is linked to social support and medication knowledge. Therefore, to reduce the occurrence of adverse consequences, healthcare providers must help recipients in strengthening their medication knowledge and establishing an effective social support system in the self-management process to enhance their self-confidence and self-management level.