Geographic Variation in HMG-CoA Reductase Inhibitor Use in Dialysis Patients

Background: Despite uncertainty about their effectiveness in chronic dialysis patients, statin use has increased in recent years. Little is known about the demographic, clinical, and geographic factors associated with statin exposure in end-stage renal disease (ESRD) patients.

Objective: To analyze the demographic, clinical, and geographic factors associated with use of statins among chronic dialysis patients.

Design: Cross-sectional analysis.

Setting: Prevalent dialysis patients across the U.S.

Participants: 55,573 chronic dialysis patients who were dually eligible for Medicaid and Medicare services during the last four months of 2005.

Methods: Using Medicaid prescription drug claims and United States Renal Data System core data, we examined demographics, comorbid conditions, and state of residence using hierarchical logistic regression models to determine their associations with statin use.

Intervention: Prescription for a statin.

Outcome Measures: Factors associated with a prescription for a statin.

Results: Statin exposure was significantly associated with older age, female sex, Caucasian (versus African-American) race, body mass index, use of self-care dialysis, diabetes, and comorbidity burden. Moreover, there was substantial state-by-state variation in statin use, with a greater than 2.3-fold difference in adjusted odds ratios between the highest- and lowest-prescribing states.

Conclusions: Among publicly insured chronic dialysis patients, there were marked differences between states in the use of HMG-CoA reductase inhibitors above and beyond patient characteristics. This suggests substantial clinical uncertainty about the utility of these medications. Understanding how such regional variations impact patient care in this high-risk population is an important focus for future work.