Prevalence and predictors of utilization of community pharmacy generic drug discount programs

Since 2006, select pharmacies in the United States have been offering programs where prescriptions for certain generic medications can be filled at very low cost (e.g., a 30-day supply for $4). However, limited knowledge exists on the characteristics of patients who have used these services.

To examine the prevalence of use of community pharmacy generic drug discount programs and the characteristics of patients using these programs.

Two cross-sectional surveys of patients in a university-affiliated health system general medicine clinic were conducted over an approximately 4-week period in the summers of 2008 and 2010. The survey measured self-reported information in 3 parts: a listing of current medications, questions about program use, and patient demographics. The survey was administered to patients as they were waiting to see their physicians with a research assistant on-site for assistance and to collect the completed surveys. Medications listed by patients were classified as acute or chronic by pharmacists on the research team. Descriptive statistics (Pearson chi-square or Student's t-tests) were used to compare subjects across years and between groups of discount program users and nonusers. Logistic regression models were constructed to identify significant predictors of program use, testing demographic factors, prescription drug coverage, number of medications, monthly out-of-pocket payments, and year of the survey.

The convenience sample included 414 individuals overall, 203 in 2008 and 211 in 2010. After excluding respondents who did not answer all survey questions, the sample size was 311 (n = 148 in 2008 and 163 in 2010). The sample was mostly Caucasian; most patients had prescription coverage; and a large majority of medications filled were for chronic use. Patient characteristics were similar in the 2 groups except for a higher mean number of self-reported medications in 2010 than 2008 (4.2 vs. 3.4, respectively, P = 0.01). Use of a discount medication program was reported by 52 (31.9%) of those surveyed in 2010 compared with 7 (4.7%) in 2008 (P less than 0.001). When both groups were combined, factors associated with use of generic drug discount programs included filling prescriptions for a higher number of medications (odds ratio [OR] =1.13, 95% CI =1.01-1.27, P =0.036) and the year of the survey (OR for 2010 =9.02, 95% CI =3.8221.29). Differences in program use were also observed among categories of age and income.

Over a 2-year period, there was an increase in the use of discount generic medication programs in this university clinic population. Patients who take more prescription medications are more likely to choose such plans, and differences in program use were observed between ranges of age and income. More extensive analysis is needed to better predict patient use of such services.