Primary Care Practice Reengineering and Associations With Patient Portal Use, Service Utilization, and Disease Control Among Patients With Hypertension and/or Diabetes

Background: We describe the role of primary care reengineering in the Ochsner Health System (OHS) patient portal implementation strategy and compare subsequent trends in service utilization and disease control among portal users vs nonusers within this context. Methods: This retrospective cohort study includes 101,019 patients with hypertension or diabetes who saw an OHS primary care provider (PCP) between 2012 and 2014. Inverse probability treatment weighting was used to reduce case-mix differences between study groups. We used generalized estimating equation modeling to compare changes in encounter rates (PCP, telephone, specialty services, emergency department [ED], inpatient hospitalization), blood pressure (BP), and hemoglobin A1c (HbA1c). Results: Age, sex, race, comorbidities, insurance, preindex utilization, and portal use were associated with changes in utilization, BP, and HbA1C; however, the strength and direction of these differences varied. An adjusted analysis comparing portal users to nonus...