A model predicting health status of patients with heart failure.

OBJECTIVE To test the causal relationships among the components of sociodemographic (age, gender, education, and income), illness characteristics (duration of illness, severity of illness, and comorbid diseases), and self-management ability, and health status in the model of health status of patients with heart failure (HSHF). DESIGN : Descriptive cross-sectional study. MATERIALS AND METHODS Participants were 400 heart failure patients hospitalized or attending an out patient clinic at six hospitals in southern Thailand. A survey-interview method was used for data collection. Questionnaires were related to study factors including sociodemographics, duration of illness, the New York Heart Association Functional Classification (NYHA-FC), the Charlson Comorbidity Index, the Self-Care of Heart Failure Index (SCHFI), the Short Form-36 Health Survey (SF-36). The relationship of the study variables was tested and modified under the structural equation modeling (SEM) technique by using LISREL. RESULTS The initial hypothesized model did not fit the data. The modified model adequately fit the data and accounted for 64% of the variance in health status. Age had a direct negative effect on health status (beta = -0.20, P < 0.01) and had an indirect negative effect on health status through self-management ability, severity of illness and comorbid disease (beta = -0.13, P < 0.01). Education had a direct positive effect on health status (beta = 0.12, P < 0.01). Gender and income had indirect negative effects on health status through severity of illness (beta = -0.05; -0.05, P < 0.05). Duration of illness had an indirect positive effect on health status through self-management ability (beta = 0.09, P < 0.05). Severity of illness and comorbid disease had a direct negative effect on health status (beta = -0.31; -0.16, P < 0.01, respectively) and indirect negative effect on health status through self-management ability (beta = -0.06; -0.05, P < 0.05, respectively). Self-management ability had a direct positive effect on health status (beta = 0.38, P < 0.01). CONCLUSIONS This model provides a guideline for explaining and predicting health status of patients with heart failure. Continuity care programs promoting self-management ability should be developed and implemented both in hospital-based and home-based settings in order to improve health status.