Importance of Adherence Versus Intensification in Attaining Blood Pressure Control

BACKGROUND: Understanding the association between improving medication adherence, intensifying antihypertensive medications, or both on blood pressure (BP) control can guide clinical care and quality improvement. METHODS: Retrospective cohort study of primary care patients with hypertension and 2 uncontrolled BP readings in 2021. Using prescription fills, we classified patients as high (≥80%) versus low (<80%) adherence in the 6 months before and after their second uncontrolled reading (aka index visit). We defined intensification as a prescription for a higher dose or a new medication class at that visit. The outcome was BP control (<130/80 mm Hg) between 30 and 270 days afterward. We identified factors associated with intensification at the index visit. For patients with low adherence before the index visit, we used multilevel logistic regression to measure the association between intensification, postvisit adherence, and subsequent BP control. RESULTS: Of 27 699 patients with uncontrolled BP, 24% had low adherence before the index visit. Patients with high adherence and prior intensification had the highest adjusted probability of intensification (28% 95% CI, 27%–29%). Among patients with low previsit adherence, 19% received intensification and 46% transitioned to high adherence. Without intensification or improved adherence, the adjusted probability of control was 23%. Neither intensification alone (24%) nor improved adherence alone (25%) significantly increased the adjusted probability of control. Patients who both received intensification and improved adherence had the highest adjusted probability of control (31%; P <0.01 versus no action). CONCLUSIONS: Physicians should simultaneously intensify treatment and encourage adherence. Health systems should encourage intensification regardless of adherence status.