The Effect of Financial Incentives on Adherence to Glucose Self-Monitoring during Pregnancy among Patients with Insulin-Requiring Diabetes: A Randomized Clinical Trial

Abstract

Objective Glucose self-monitoring is critical for the management of diabetes in pregnancy, and increased adherence to testing is associated with improved obstetrical outcomes. Incentives have been shown to improve adherence to diabetes self-management. We hypothesized that use of financial incentives in pregnancies complicated by diabetes would improve adherence to glucose self-monitoring. Study Design We conducted a single center, randomized clinical trial from May 2016 to July 2019. In total, 130 pregnant patients, <29 weeks with insulin requiring diabetes, were recruited. Participants were randomized in a 1:1:1 ratio to one of three payment groups: control, positive incentive, and loss aversion. The control group received $25 upon enrollment. The positive incentive group received 10 cents/test, and the loss aversion group received $100 for >95% adherence and “lost” payment for decreasing adherence. The primary outcome was percent adherence to recommended glucose self-monitoring where adherence was reliably quantified using a cellular-enabled glucometer. Adherence, calculated as the number of tests per day divided by the number of recommended tests per day×100%, was averaged from time of enrollment until admission for delivery. Results We enrolled 130 participants and the 117 participants included in the final analysis had similar baseline characteristics across the three groups. Average adherence rates in the loss aversion, control and positive incentive groups were 69% (SE=5.12), 57% (SE = 4.60), and 58% (SE=3.75), respectively (p=0.099). The loss aversion group received an average of $50 compared with $38 (positive incentive) and $25 (control). Conclusion In this randomized clinical trial, loss aversion incentives tended toward higher adherence to glucose self-monitoring among patients whose pregnancies were complicated by diabetes, though did not reach statistical significance. Further studies are needed to determine whether use of incentives improve maternal and neonatal outcomes. Key Points