Effect of Financial Incentives for Process, Outcomes, or Both on Cholesterol Level Change: A Randomized Clinical Trial

IMPORTANCE: Financial incentives may improve health behaviors. It is unknown whether incentives are more effective if they target a key process (eg, medication adherence), an outcome (eg, low-density lipoprotein cholesterol [LDL-C] levels), or both. OBJECTIVE: To determine whether financial incentives awarded daily for process (adherence to statins), awarded quarterly for outcomes (personalized LDL-C level targets), or awarded for process plus outcomes induce reductions in LDL-C levels compared with control. DESIGN, SETTING, AND PARTICIPANTS: A randomized clinical trial was conducted from February 12, 2015, to October 3, 2018; data analysis was performed from October 4, 2018, to May 27, 2021, at the University of Pennsylvania Health System, Philadelphia. Participants included 764 adults with an active statin prescription, elevated risk of atherosclerotic cardiovascular disease, suboptimal LDL-C level, and evidence of imperfect adherence to statin medication. INTERVENTIONS: Interventions lasted 12 months. All participants received a smart pill bottle to measure adherence and underwent LDL-C measurement every 3 months. In the process group, daily financial incentives were awarded for statin adherence. In the outcomes group, participants received incentives for achieving or sustaining at least a quarterly 10-mg/dL LDL-C level reduction. The process plus outcomes group participants were eligible for incentives split between statin adherence and quarterly LDL-C level targets. MAIN OUTCOMES AND MEASURES: Change in LDL-C level from baseline to 12 months, determined using intention-to-treat analysis. RESULTS: Of the 764 participants, 390 were women (51.2%); mean (SD) age was 62.4 (10.0) years, 310 (40.6%) had diabetes, 298 (39.0%) had hypertension, and mean (SD) baseline LDL-C level was 138.8 (37.6) mg/dL. Mean LDL-C level reductions from baseline to 12 months were −36.9 mg/dL (95% CI, −42.0 to −31.9 mg/dL) among control participants, −40.0 mg/dL (95% CI, −44.7 to −35.4 mg/dL) among process participants, −41.6 mg/dL (95% CI, −46.3 to −37.0 mg/dL) among outcomes participants, and −42.8 mg/dL (95% CI, −47.4 to −38.1 mg/dL) among process plus outcomes participants. In exploratory analysis among participants with diabetes and hypertension, no spillover effects of incentives were detected compared with the control group on hemoglobin A(1c) level and blood pressure over 12 months. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, process-, outcomes-, or process plus outcomes–based financial incentives did not improve LDL-C levels vs control. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02246959