Objective: Adherence to antihypertensive medications is often less than optimal. Research suggests that patients have limited confidence regarding whether office blood pressure (BP) assessments represent their 'true' BP, which may further promote poor adherence to BP-lowering medication. We assessed peoples' confidence in the methods of BP assessment and examined the associations between patients' confidence levels and medication adherence comparing office and home BP-monitoring techniques.
Methods: We surveyed US adults aged 30 years or older (N=1010), all of whom had undergone an office BP measurement within the past 6 months. Respondents who indicated being prescribed antihypertensive medication (N=429) were asked to indicate their level of confidence on a 1-9 scale that BP measurements represented their true BP, and their adherence to antihypertensive medication using the eight-item Morisky Medical Adherence Scale (MMAS-8).
Results: Respondents had equal confidence that both office BP measurements and home monitoring measurements reflected their true BP (median=7). Respondents indicated that they would have slightly more confidence in ambulatory BP monitoring (median=8). As respondents' confidence in the assessments of BP from office measurements and home monitoring increased from 1 to 9, the mean MMAS-8 score, adjusted for age, race, and education, increased from 5.38 to 6.25 (P=0.053) and from 5.50 to 6.14 (P=0.25), respectively.
Conclusion: As patients' confidence in a BP assessment method increases, so too does their reported adherence to prescribed antihypertensive medications. This finding further supports the incorporation of methods in which patients can feel confident that the measurements are representative of their 'true' BP.