A causal model of medication adherence behavior in the elderly with hypertension

Abstract

The purpose of this study was to examine the causal relationship among regimen complexity, family income, age, health beliefs, cognitive function, social support, and medication adherence behavior in the elderly with hypertension. The srudy was based on medication adherence model (Park and Jones, 1997). Multi-stage random sampling was employed to obtain the sample of 422 elderly with hypertension who visited five general hospitals in Thailand. Research instruments consisted of the Chula Mental Test, the Health Belief Questionnaire, the Personal Resource Questionnaire, the Medication Regimen Complexity Index, and the Morisky Medication Adherence Scale. Data were analyzed using SPSS for Window version 15 and LISREL version 8.52. The goodness of fit indices illustrated that medication adherence model fit with the empirical data (X² = 57.77, df= 42, p-value = 0.053, GFI=0.98, AGFI=0.95, RMSEA= 0.03), and explained 70% of the variance of medication adherence. Cognitive function, health beliefs, and social support have positive direct effect on medication adherence. Social support was the most influential factor affecting medication adherence. In addition, regimen complexity and family income had a significant positive direct effect on health beliefs and had a significant positive indirect effect on medication adherence through health beliefs. Family income had a significant positive direct effect on cognitive function and indirect effect on medication adherence through cognitive function. Age had a significant negative direct effect on cognitive function and indirect effect on medication adherence through cognitive function. The findings indicated the prominent components of nursing intervention focusing on promote medication adherence behavior in the elderly with hypertension. Nurses should assessment about age, family income, cognitive function, regimen complexity of the elderly. Promote social support and health beliefs in the elderly with hypertension.