Does increased adherence to medications change health care financial burdens for adults with diabetes?

The aim of the present study was to investigate increased out-of-pocket drug costs and financial burdens of achieving adherence to oral antidiabetic medications and medications for prevalent comorbidities.

Concurrent adherence to medications, out-of-pocket drug costs, and financial burdens were measured among non-elderly adults with diabetes in the Medical Expenditure Panel Survey. "Financial burden" was defined as spending on health care exceeding 10% of family income. This study simulated the increased out-of-pocket drug costs and financial burdens that would result if non-adherent adults in our sample had obtained sufficient medications to be adherent. For each adult, for all therapeutic classes in which they were non-adherent, we calculated the additional days supplied required to become adherent, as well as out-of-pocket spending on these additional days supplied.

Approximately one-quarter adhered to all required medications. Among non-adherent adults with employer-sponsored insurance and public insurance, the mean annual out-of-pocket drug costs of achieving adherence were US$171 and US$68, respectively, which was generally affordable. However, 35.6% of the uninsured lived in families that spent 10% or more of their income on health care. Mean simulated additional out-of-pocket drug costs of achieving adherence were US$310 for the uninsured. These additional drug costs would increase those spending 10% or more of income to 39.6% of the uninsured.

Efforts to reduce the costs faced by the uninsured and insured will make adherence more affordable and, therefore, more attainable for some adults with diabetes.