Impact of type 2 diabetes mellitus on prescription medication burden and out-of-pocket healthcare expenses

Aims: The number of prescription medications and out-of-pocket expenses of individuals with type 2 diabetes mellitus (T2DM) were evaluated to assess the economic burden of diabetes. Methods: The self-reported number of prescription medications and out-of-pocket health-care expenses were evaluated from respondents of the United States SHIELD study with and without a diagnosis of T2DM. Medications included monotherapy and combination therapy; combination tablets were counted as one agent. Analysis of variance and multivariate linear regression models adjusted for age, gender, prescription insurance coverage, and household income. Results: Of the T2DM respondents (n = 3551), 40% were on 1 prescription antidiabetic agent (7% insulin alone), 26% were on 2 agents, 8% were on >= 3 agents, with a mean of 1.3 antidiabetic agents. After adjusting for age, gender, insurance coverage, and income, respondents with T2DM had a significantly larger total number of prescriptions (6.2) and higher out-of-pocket expenses for both annual medical ($1158) and monthly prescription ($144) expenses, compared with respondents without T2DM (n = 8686) (4.1 prescriptions, $925 annual medical, $118 monthly prescription) (p < 0.01). Conclusions: Increased out-of-pocket medical and medication costs in T2DM are due to the use of both antidiabetic agents and other medications for treatment of comorbid conditions. (C) 2009 Elsevier Ireland Ltd. All rights reserved.