The effectiveness of financial incentives on clinical outcomes of cardiovascular disease risk factors: A systematic review and meta-analysis

Objectives We sought to examine studies that assessed the effects of financial incentives contingent on clinical improvement on factors associated with cardiovascular disease (CVD) risk. Study design Systematic review and meta-analysis. Methods Databases were searched for randomized controlled trials (RCTs). We included only RCTs with incentives contingent on clinical improvement using consistent parameters. Meta-analyses and subgroup analyses were conducted for outcomes: smoking cessation, glycemic control, blood pressure, and serum cholesterol. Analyses were conducted using Cochrane Review Manager software. Study quality was assessed with RoB 2.0. Results Data from 43 trials were analyzed: 18 smoking cessation (n = 15,772), 19 wt loss (n = 4416), three glycemic control (n = 418), two hypercholesterolemia trials (n = 543), and one hypertension trial (n = 207). Studies’ duration varied from three months to two years. Meta-analyses showed reductions in smoking [risk ratio (RR) 1.56, 95% CI 1.42 to 1.72], change in body weight (kg) [mean difference (MD) −1.2, 95% CI -1.57 to −0.84], and glycated haemoglobin (HbA1c) (%) (MD of −0.43, 95% CI -0.69 to −0.18) by the end of the study period. The analysis of the two studies on low-density lipoprotein cholesterol (LDL-C) (mg/dL) (MD-0.3, 95% CI -4.34 to 3.73) did not reveal a significant effect. Conclusions Financial incentives can effectively promote smoking cessation and modest weight loss. Evidence for their effect on glycemic control was promising but limited, while no significant effects were found for LDL-C or blood pressure. Incentives based on clinical outcomes should be assessed for their long-term applicability in managing chronic diseases.