Value-based insurance design reduces patient copayments to encourage the use of health care services of high clinical value. As employers face constant pressure to control health care costs, this type of coverage has received much attention as a cost-savings device. This paper's examination of one value-based insurance design program found that the program led to reduced use of nondrug health care services, offsetting the costs associated with additional use of drugs encouraged by the program. The findings suggest that value-based insurance design programs do not increase total systemwide medical spending.

BACKGROUND: Increasing patient cost sharing is a commonly employed mechanism to contain health care expenditures. OBJECTIVE: To explore whether the impact of increases in prescription drug copayments differs between high- and low-income areas. DESIGN: Using a database of 6 million enrollees with employer-sponsored health insurance, econometric models were used to examine the relationship between changes in drug copayments and adherence with medications for the treatment of diabetes mellitus (DM) and congestive heart failure (CHF). SUBJECTS: Individuals 18 years of age and older meeting prespecified diagnostic criteria for DM or CHF were included. MEASUREMENTS: Median household income in the patient's ZIP code of residence from the 2000 Census was used as the measure of income. Adherence was measured by medication possession ratio: the proportion of days on which a patient had a medication available. RESULTS: Patients in low-income areas were more sensitive to copayment changes than patients in high- or middle-income areas. The relationship between income and price sensitivity was particularly strong for CHF patients. Above the lowest income category, price responsiveness to copayment rates was not consistently related to income. CONCLUSIONS: The relationship between medication adherence and income may account for a portion of the observed disparities in health across socioeconomic groups. Rising copayments may worsen disparities and adversely affect health, particularly among patients living in low-income areas.

This paper estimates the effects of a large employer's value-based insurance initiative designed to improve adherence to recommended treatment regimens. The intervention reduced copayments for five chronic medication classes in the context of a disease management (DM) program. Compared to a control employer that used the same DM program, adherence to medications in the value-based intervention increased for four of five medication classes, reducing nonadherence by 7-14 percent. The results demonstrate the potential for copayment reductions for highly valued services to increase medication adherence above the effects of existing DM programs.