In this study, 334 elderly chronic heart failure patients (194 females and 140 males) who were hospitalized at four teaching hospitals in Mazandaran province, Iran were selected through convenience sampling. The inclusion criteria included a history of at least 6 months of involvement with heart failure, age ≥ 60, and being in a stable condition (1 - 2 days after admission). The exclusion criteria included communication problems (such as severe hearing impairment with no hearing aids or speech problems), severe cognitive impairment with abbreviated mental test scores (AMT) < 4 (
8), and uncooperativeness.
Data was gathered from patients’ medical documents and through interviews. In this study, the factors predicting SCB were derived from Moser’s conceptual model (
4) and the WHO adherence model (
9). Then, a preliminary study was performed on 184 elderly individuals with HF (
3).
Psychosocial factors consisted of gender, location, living arrangement, education level, income, perceived social supports, and depressive symptoms.
Age-related factors consisted of cognitive status, functional status, attitude toward aging, comorbidities (Charlson comorbidity index), poly-pharmacy (taking 5 or more different drugs), hearing impairment, and visual impairment.
Clinical factors consisted of left ventricular ejection fraction (LVEF), the severity of disease (NYHA classification), sleep disorders, systolic blood pressure, body mass index, and some biochemical characteristics of the blood.
Prior experiences consisted of a history of hospitalization for heart failure during the prior 6 months, history of teaching about heart failure, satisfaction with teaching, and satisfaction with treatment.
Variables that had a significant relationship with SCB based on single-variable analysis (social support, depressive symptoms, living arrangement, income, cognitive status, functional status, attitude toward aging, Charlson index, visual impairment, hearing impairment, poly-pharmacy, sodium serum level, systolic BP, ejection fraction, NYHA Class, sleep disorders, history of teaching about heart failure, satisfaction with teaching, and satisfaction with treatment ) and variables with P < 0.3 (gender, education, location, disease severity) entered the model.
Heart failure self-care was evaluated before hospitalization. To assess self-care behaviors, the European heart failure self-care behaviors (EHFSCB) questionnaire was used (
10). This 12-item scale measured self-care behaviors on a 5-point Likert scale ranging from 1 (strongly agree) to 5 (strongly disagree). The total score was considered and a lower score indicated better self-care. The content validity index (CVI) of this study was confirmed by an expert panel comprised of 10 cardiologists and cardiac nurse specialists with histories of at least 5 years of work in the field (CVI = 0.97). Its reliability was assessed by Cronbach’s alpha (α = 0.74).
Social support was defined as self-reported perceived social support from family, friends, or significant other and was assessed using the multidimensional scale of perceived social support (MSPSS). In our country, its Cronbach’s alpha was reported as 0.92 (
11). In our study, the Cronbach’s alpha was 0.9.
Depressive symptoms were assessed using the geriatric depression scale (GDS). In our country, the sensitivity and specificity of the cut of point 6, has been reported as 0.9 and 0.83 (
12). In our study the Cronbach’s alpha was 0.7.
Cognitive status was measured using the Iranian version of abbreviated mental test (AMT) (
13). In our country the ideal cut of the point has been identified as six and its sensitivity and specificity was 85% and 99% (
13). In our study, the Cronbach’s alpha was 0.76.
Functional status was measured using Iranian version of activity daily living (Katz, 1963) (ADL) and instrumental activity daily living (Lawton 1969) (IADL). In our country, its reliability was reported as 0.9 by test-retest (
14). In our study the Cronbach’s alpha of IADL and ADL were 0.78 and 0.81, respectively.
Attitudes toward aging status were measured using Iranian version of Philadelphia geriatric center moral score. In our country, its Cronbach’s alpha was reported as 0.82 (
15). In our study the Cronbach’s alpha was 0.68.
Sleep status was measured using the Iranian version of Epworth sleepiness scale. In our country, its Cronbach’s alpha was reported as 0.75 (
16). In our study the Cronbach’s alpha was 0.79.
All eligible patients were approached by the research nurse. After providing written informed consent, each patient was interviewed by an independent data collector who was not involved in caring for the patient. This study was approved by the Ethics Committee of Mazandaran University of Medical Sciences and complies ethically with the declaration of Helsinki.
The SPSS version 20.0 was used for data analysis. Dummy codes were used with gender, education, income, and location. All the assumptions of multivariate analyses were assessed and met, including normality, homoscedasticity, linearity, and multi-collinearity. The initial hypothesized model was tested under a structural equation modeling (SEM) technique through Amos 20.0. Confirmatory factor analyses (CFA) were conducted before testing the full model to evaluate the four measurement models for their model fit.
Indicators of the overall fit of the model were the goodness of fit index (GFI), comparative fit index (CFI), and normed fit index (NFI). Values above 0.9 were regarded as adequate and above 0.95 reflected a good model fit. The root mean square error of approximation (RMSEA) was used to determine the parsimonious fit of the model. A RMSEA value of less than 0.05 indicated a good fit, a value between 0.05 and 0.08 showed a moderate fit, and values between 0.08 and 0.10 indicated a fair fit, while values more than 0.10 indicated a poor fit.