Association of Illness Perception and Antihypertensive Medicationadherence among Black Hypertensive Adults in Primary Care Settings

Stella Eke

Abstract

Background: Black adults with hypertension are more likely to have uncontrolled hypertension, suffer more complications and have poorer medication adherence than Whites. Poor medication adherence has been identified as a contributing factor to the high burden of uncontrolled hypertension among Blacks. Several studies have found that Black adults with hypertension have numerous misconceptions about it and its management; however, very few studies have examined hypertension perceptions in relation to antihypertensive medication adherence.

Purpose: The primary aim was to investigate the relationship between hypertension perceptions and medication adherence among Black hypertensive adults 35 to 65 years old in primary care settings. Additional aims were to examine the factor structure of hypertension causal attributions and to explore gender differences in hypertension perceptions and medication adherence.

Method: The Common-sense Illness model of perception and self-regulation served as the theoretical framework for this cross-sectional study. A nonprobability sample of 118 Black hypertensive adults 35 to 65 years old was selected as they presented in four primary care clinics. Instruments included the revised Illness Perception Questionnaire (IPQ-R) and the Hill-Bone Blood Pressure Therapy Compliance scale.

Results: The sample was middle aged (M=53.9; SD = 7.9 years); 52.5% male; and mostly educated, with 51% having four-year college degree or higher. Using principal components factor analysis, two factors emerged, which explained 40.8% variance in hypertension causal attributions. Factor 1 contains items related to unhealthy lifestyle choices and factors outside the individual’s control. Factor 2 contains items related to life stressors and known hypertension predisposing factors. Using multiple regression while controlling for covariates, three IPQ-R subscales (Timeline-cyclical, Consequences and Emotional representation together explained 23.9% variance in medication adherence, F (6, 111) = 5.82, P < .001); however only “Consequences” had a statistically significant relationship with medication adherence (p = .022). Using ANCOVA, only one of nine subscales had a significant gender difference; males had higher (p = .034) adjusted mean scores (M= 16.2, s.e.=.64.) than females (M = 14.2, s.e.=.67) on the perception that hypertension is caused by factors related to unhealthy lifestyle choices and factors outside an individual’s control.

Conclusion: Two reliable factors of causal attributions emerged. Perception that hypertension induces burden on life (Consequences) was the only perception that significantly predicted medication adherence. Males and females were very similar in their perceptions of hypertension. Although these findings could be applied to similar patient populations in primary care, variation in antihypertensive medication adherence is largely unexplained and needs further research. A longitudinal study with a larger sample size may be needed to further examine and clarify hypertension beliefs among Black hypertensive adults.