OBJECTIVES: 1. To determine the pattern of adherence to statins among the diabetes patients at a self-insured university.  2. To determine the effect of independent variables [age, gender, co-payment, and campus location (main campus/health science campus)] on adherence to statins. METHODS: Pharmacy claims data was used to identify patients using both diabetes and statin drugs during the study period between January 1, 2006 and June 2, 2008. Adherence to statins was calculated at regular observation periods using Medication possession ratio (MPR). Patients with MPR ≥ 80% were considered adherent. Patients with MPR < 80% were considered non-adherent. Logistic regression was used to study the effect of independent variables on adherence to statins. RESULTS: Two hundred and ninety-five patients were included in the study. The mean age of the patients was 55.09 ± 9.30 years. The mean MPR of statins was 0.76, 0.70, and 0.68 in the 6, 12, and 24 months observation periods respectively. During the first six months, about 58% of patients were adherent to statins with MPR ≥ 0.80. About 51% and 48% of patients were adherent to statins during the 12 and 24 months observation periods. Age was significantly positively associated with adherence to statins (Odds ratio, 1.04; 95% CI, 1.01-1.07). Males were 48.3% more likely to be adherent than females (p=0.05). CONCLUSIONS: American Diabetes Association guidelines recommend statin therapy in every diabetes patients of age 40 years and above, regardless of their low-density lipoprotein level. Low adherence can result in the development of cardiovascular diseases, which can lead to increase in outpatient and emergency room visits and hence, increase in the healthcare costs. Adherence to statins was suboptimal among this study population. This presents an increased risk of developing cardiovascular diseases, which can lead to increases in the healthcare costs for this self-insured university.