Long-term Outcomes of a 1-year Hypertension Quality Improvement Initiative in a Large Health System

Abstract

Background: Understanding whether practices retain outcomes attained during a quality improvement (QI) initiative can inform resource allocation. Objective: We report blood pressure (BP) control and medication intensification in the 3 years after a 2016 QI initiative ended. Research Design: Retrospective cohort Subjects: Adults with a diagnosis of hypertension who had a primary care visit in a large-integrated health system between 2015 and 2019 Measures: We report BP control (<140/90 mm Hg) at the last reading of each year. We used a multilevel regression to identify the adjusted propensity to receive medication intensification among patients with an elevated BP in the first half of the year. To examine variation, we identified the average predicted probability of control for each practice. Finally, we grouped practices by the proportion of their patients whose BP was controlled in 2016: lowest performing (<75%), middle (≥75%–<85%), and highest performing (≥85%). Results: The dataset contained 184,981 patients. From 2015 to 2019, the percentage of patients in control increased from 74% to 82%. In 2015, 38% of patients with elevated BP received medication intensification. This increased to 44% in 2016 and 50% in 2019. Practices varied in average BP control (from 62% to 91% in 2016 and 68% to 90% in 2019). All but one practice had a substantial increase from 2015 to 2016. Most maintained the gains through 2019. Higher-performing practices were more likely to intensify medications than lower-performing practices. Conclusions: Most practices maintained gains 3 years after the QI program ended. Low-performing practices should be the focus of QI programs.