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

Abstract

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 A1c 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.

Conflict of interest statement

Conflict of Interest Disclosures: Dr Barankay reported receiving research support from Humana Inc outside the submitted work. Dr Reese reported receiving investigator-initiated grants from CVS Caremark to the University of Pennsylvania to support studies of medication adherence; grants from Merck, Gilead, and AbbVie to support clinical trials in transplantation; and personal fees from the American Journal of Kidney Diseases and from VAL Health for consulting related to chronic kidney disease care outside the submitted work. Dr Volpp reported receiving personal fees from and being a principal of VAL Health, a behavioral economics consulting company; serving as a consultant for CVS Caremark; receiving research support from Vitality/Discovery, Humana, WW, Hawaii Medical Service Association, and Merck; and receiving consulting fees from the Center for Corporate Innovation, Lehigh Valley Medical Center, Vizient, Greater Philadelphia Business Coalition on Health, American Gastroenterological Association Tech Conference, Bridge to Population Health Meeting, and Irish Medtech Summit, all outside the submitted work. Dr Loewenstein reported serving as a consultant for BI Worldwide, Florida Blue, VAL Health, United Healthcare, and serving on the board of NPD, all outside the submitted work. No other disclosures were reported.

Figures

Figure 1.. Consolidated Standards of Reporting Trials Diagram

LDL-C indicates low-density lipoprotein cholesterol. SI conversion factor: To convert LDL-C to millimoles per liter, multiply by 0.0259.

Figure 2.. Mean Low-Density Lipoprotein Cholesterol (LDL-C) Levels by Visit and Intervention Group

Error bars indicate 95% CIs. SI Conversion factor: To convert LDL-C to millimoles per liter, multiply by 0.0259.

Figure 3.. Spillover Analyses of Hemoglobin A1c (HbA1c) Level and Systolic Blood Pressure by Intervention Group

The horizontal line in the boxes indicates the median. The upper and lower ends of the boxes are 75th and 25th percentiles. The upper and lower whiskers are 1.5 times the interval range. The circles represent outliers. SI conversion factor: To convert HbA1c to proportion of total hemoglobin, multiply by 0.01.