The incidence and prevalence of chronic heart failure (CHF) are increasing because of the increase in the aging population and improved treatment strategies. CHF is a leading cause of morbidity and mortality in the elderly and imposes a heavy economic burden on families and society in general. Patients with CHF are characterized by poor and impaired quality of life because of the unpredictable risk of deterioration and decompensation, coexisting symptoms, high cost of treatment, high readmission rates, and poor prognosis [1]. Individual factors that affect their quality of life include sex, age, New York Heart Association (NYHA) classification, personality, self-care monitoring, knowledge about CHF, education level, financial situation, frequency of hospitalization, co-morbidities, support from family members and caregivers, occupation, and psychological and social factors [2, 3].

Depression is a prevalent comorbidity in patients with CHF, and most patients experience its symptoms. It increases the need for readmission and mortality and has a strong negative impact on the quality of life of patients; a more severe depression is associated with a poorer quality of life [3]. Poor quality of life, in turn, exacerbates the symptoms of depression. Depression is difficult to treat in patients with CHF, as these patients do not benefit from general education programs [4]. A large randomized clinical trial found no significant differences between anti-depression medicines and placebos in reducing depression symptoms or improving cardiovascular status among patients with heart failure and depression [5].

Self-care is an important element in the management of CHF. Accumulating evidence demonstrates that self-care behaviors are important for reducing mortality and morbidity and improving the quality of life. However, inadequate self-care is common in patients with CHF, especially the elderly with a history of depression [6]. Factors that influence the quality of life of patients with CHF also affect the self-care behavior of these patients [7], and the habit of exhibiting poor self-care behavior is difficult to modify [8].

Depression, self-care capacity, and quality of life interact and influence each other. Older age predicts poorer health outcomes and is associated with a more severe depression, greater self-care deficit, and poorer quality of life [3, 6]. Furthermore, inadequate health literacy is especially common in older patients. Thus, to improve the quality of life and outcomes in elderly patients with CHF, comprehensive and exclusive theory-based education programs are required in addition to conventional therapy to target heart failure-related factors.

The PRECEDE planning model used in the present study was developed by Green et al. [9]. PRECEDE stands for predisposing, reinforcing, and enabling constructs in educational/environmental diagnosis and evaluation. The strategy of this model involves thorough analysis of multiple dimensions, including sociology, epidemiology, behavior, environment, education, organization, and management policy, for the development of a health education intervention, implementation of the intervention, and evaluation of the process, impact, and outcomes of the intervention [10]. This model is especially appropriate for application in chronic diseases, and its effectiveness in reducing depression and increasing quality of life has been demonstrated in different subjects, including patients who have undergone coronary artery bypass grafting (CABG) [10], those with type 2 diabetes [11–13], and the elderly [14]. However, to our knowledge, it has not been used in elderly patients with CHF.

Thus, the present study aimed to use the PRECEDE model to optimally tailor a health education promotion program among elderly patients with CHF and investigate its effect on depression, self-care behavior, and quality of life.

Between March 2015 and January 2016, patients with CHF who met the inclusion criteria were selected from the Department of Geriatrics and Cardiology of our hospital. Sixty-six patients were recruited and randomly divided into the intervention and control groups in accordance with a randomized computer-generated number table. Four patients were lost to follow-up for various reasons (rate of loss to follow-up, 6.06%). Finally, 31 patients in the control group and 31 in the intervention group completed the study.

The inclusion criteria were CHF with NYHA class II–IV, age ≥ 60 years, presence of typical symptoms, and signs of CHF that disappeared after effective treatment, stable condition, and discharge from the hospital. Patients were excluded when they met the following exclusion criteria: unable to complete the questionnaire; scheduled for an operation within 6 months; had other diseases and an expected survival time < 1 year; had an unstable condition such as that in end-stage heart failure; or had diseases that significantly affected their ability to conduct physical activities.

The general characteristics of the patients were recorded, including name, age, sex, body mass index (BMI), marital and insurance statuses, education level, financial situation, availability of caregivers, comorbidities, time of diagnosis of heart failure, previous hospitalization for heart failure, and NYHA classification.

No significant differences were found in the mean age of the patients in the intervention and control groups (63.97 ± 14.47 vs. 62.84 ± 13.40, P = 0.75). Other general characteristics, including sex, BMI, education level, medical insurance status, the time of CHF onset, NYHA classification, and comorbidities, also showed no significant differences between the groups (P > 0.05).

The Pearson correlation analysis revealed that the MLHFQ score significantly and positively correlated with the EHFScBS-9 (r = 0.463, P < 0.001) and PHQ-9 scores (r = 0.584, P < 0.001) after the intervention. These findings indicate that the symptoms of depression and self-care ability directly influence the quality of life of elderly patients with CHF.

The findings of this study showed that after the education intervention based on the theory of the PRECEDE model, the scores for predisposing, reinforcing, and enabling factors increased significantly and the mean total scores in the EHFScBS-9, PHQ-9, and MLHFQ decreased significantly in the intervention group. Furthermore, these scores differed significantly from the corresponding scores in the control group. The MLHFQ score significantly correlated with the EHFScBS-9 and PHQ-9 scores.

The mean scores of the PRECEDE model constructs, including knowledge, attitude, and enabling and reinforcing factors, increased after the intervention in this study. This finding is consistent with those of previous studies conducted in patients with CABG [25]. Health literacy (predisposing factors) is “the capacity to obtain, read, understand, and process health-related information” [26]. Studies have shown that old age is associated with poor health literacy, which in turn leads to poor outcomes [26, 27]. Social support includes informational (predisposing factors), instrumental (predisposing and enabling factors), and emotional supports (reinforcing factors) [28]. It is associated with depression, self-care, and quality of life, particularly in the emotional dimension, among older patients with CHF [28]. These results indicate that targeting these factors may improve patient outcomes. Previous family or nursing support programs have been shown to improve self-care behaviors and quality of life in patients with heart failure [29, 30]. Our results confirmed these findings and revealed the possibility that the education intervention based on the PRECEDE model focuses on multiple factors and is effective in understanding and adhering to disease management strategies, thereby enhancing self-care behaviors.

Lack of self-care behaviors and presence of depression symptoms are common among patients with CHF, especially the elderly, as shown in our study. The patients had high EHFScBS-9 and PHQ-9 scores before the intervention, which suggests the necessity of an education intervention. Self-care management, depression, and quality of life have reciprocal causation and exacerbate one another. EHFScBS-9 scores have been shown to correlate with depression [7]. Depression leads to a lack of motivation and enthusiasm, and compromises adherence to self-care behaviors. Inadequate self-care behaviors and depression are predictors of poor quality of life and are associated with readmission and high mortality rates [22, 31]. The results of the present study also showed that quality of life positively correlated with the self-care behaviors and symptoms of depression in the elderly patients with CHF.

Other health education strategies have been reported to benefit patients with CHF. For example, the self-management education programs are effective in increasing quality of life and treatment satisfaction [32], and the supportive educational nursing care programs can alleviate fatigue and improve quality of life [30]. Self-care programs can ameliorate heart function and reinforce the patient’s ability and efficiency to perform self-care [33], and home-based disease management programs can improve psychological status, including depression and anxiety [34]. These studies provide evidence that apart from standard therapy, patients with heart failure can additionally benefit from special education promotion programs.

Previous studies confirmed the effectiveness of the PRECEDE model-based education intervention for controlling depression symptoms and severity, and improving sleep status and quality of life in patients with CABG [10, 25, 35]; improving the quality of life of the elderly [14]; and enhancing self-care behaviors and control of HbA1c level, blood pressure, lipid profile, and BMI in patients with type 2 diabetes [11–13]. To our knowledge, its effect in elderly patients with CHF has not been investigated before. The present study expanded the application the PRECEDE model-based education intervention and, for the first time, demonstrated its usefulness in relieving depression symptoms, promoting self-care monitoring, and eventually improving the quality of life of elderly patients with CHF. In the present study, although conventional therapy also improved the patients’ quality of life, the intervention group showed much greater improvements. In addition, after the intervention, no improvements were observed in the score in the “exercise regularly” item of EHFScBS-9, possibly because the subjects in this study were elderly patients, who tend to be frail and have more disabilities and co-morbidities than young adults, which influence their activities.

Although the study demonstrates PRECEDE-based education model is effective in relieving depression symptoms, enhancing self-monitoring and improving the quality of life in elderly patients with CHF, the limitation of our study is the numbers of subjects are small. It would not be enough to draw a meaningful conclusion. Further studies will be needed with a larger patient number.

Our study demonstrated a trend that the education promotion program based on PRECEDE maybe a useful method to enhance self-care behaviors, improve the depressive state and quality of life in elderly patients with CHF. It provides a rational foundation for future large-scale clinical trials that could further demonstrate the application and effectiveness of this education model.