Shared financial incentives between physicians and patients resulted in a cost-effective strategy for reducing low-density lipoprotein cholesterol (LDL-C) levels in patients who risked cardiovascular disease, according to a study published in JAMA Network Open.
The study authors extracted data from a randomized clinical trial on financial incentives and drew a representative model population from the National Health and Nutrition Examination Surveys. Participants had a history of cardiovascular disease events, diabetes, or LDL-C levels above 120 mg/dL or risk factors for coronary heart disease.
Using a previously validated microsimulation computer model, the authors simulated long-term discounted cost and health consequences related to financial incentives for controlling cholesterol. Outcomes were captured for model time horizons, including a lifetime horizon used in the base-case analysis and varied time horizons used in sensitivity analyses.
Each individual in the model was simulated for 5 different intervention strategies: a virtual control group that received usual care, a trial control group that received increased cholesterol monitoring and involved electronic pill bottle use, financial incentives for physicians, financial incentives for patients, and shared incentives for both physicians and patients. Primary outcomes were measured as discounted costs in US dollars, lifetime risk of cardiovascular disease, quality-adjusted life-years, and incremental cost-effectiveness ratios. The threshold for cost-effectiveness was defined at $100,000 or $150,000 per quality-adjusted life year.
Mean age and LDL-C levels of the model population subset (n=1,000,000) were similar to those observed in the trial population (n=1503). Using base-case assumptions, the virtual control group was dominated by all other strategies, reporting elevated lifetime costs and fewer quality-adjusted life-years. Strategies for physician-only or patient-only incentives were both dominated by the shared-incentives strategy.
The shared-incentives strategy had a higher incremental cost-effectiveness ratio, at $60,000 per quality-adjusted life-year compared to the trial control group, meeting cost-effectiveness thresholds.
Sensitivity analyses performed with different assumptions for the duration of LDL-C level reductions and years of intervention costs showed that the study results were sensitive to duration factors beyond the intervention. The base-case analysis assumed a 10-year linear waning of LDL-C reduction, but the shared-incentives strategy remained cost-effective when adjusting for scenarios in which LDL-C level reductions persisted with linear waning for 7 and 5 years (with incremental cost-effectiveness ratios of $85,000 and $130,000 per quality-adjusted life-year, respectively).
However, in the 1-way sensitivity analysis for model time horizons, the incremental cost-effectiveness ratio of the shared-incentives strategy exceeded $100,000 per quality-adjusted life-year at 11 years and $150,000 per quality-adjusted life-year at 8 years. In probabilistic sensitivity analysis, the shared-incentives intervention was cost-effective in 69% to 77% of iterations using defined cost-effectiveness thresholds.
Limitations of the study include the extrapolation of observed trial findings into future years to generate lifetime estimates and background changes in cardiovascular disease risk factors. The clinical trial used a selected population, and the results may have been more optimistic than could be expected in real-world practice. The authors performed their analysis from the payer perspective; incremental cost-effectiveness ratios would have been more favorable for incentive strategies from a societal perspective.
The study authors suggest that implementing shared financial incentives between physicians and patients is a cost-effective intervention strategy for for controlling LDL-C levels among high-risk patients. However, the results were sensitive to the durations of LDL-C level reductions and the years of intervention costs; further studies are needed to assess whether shared incentives could be adopted and remain effective on a long-term basis.
Reference
Pandya A, Asch DA, Volpp KG, et al. Cost-effectiveness of financial incentives for patients and physicians to manage low-density lipoprotein cholesterol levels [published online August 14, 2018]. JAMA Netw Open. doi:10.1001/jamanetworkopen.2018.2008