Frequency of Disparities in Laboratory Testing After Statin Initiation in Subjects ≥65 Years

Abstract

Laboratory testing is important for the safety of older adults initiating statins, but there has been little examination of laboratory testing disparities by race/ethnicity, age, gender, Medicaid eligibility, and multimorbidity. The study's purpose was to examine disparities in guideline-concordant baseline laboratory testing and abnormal laboratory values among a retrospective cohort of 76,868 Medicare fee-for-service beneficiaries from 10 states in the eastern United States who had dyslipidemia and initiated a statin from July 1 to November 30, 2011. Guideline-concordant assessment of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) was defined as evidence of an outpatient claim for either test within 180days before or 14days after the date of the index statin fill. In 2011, baseline laboratory testing rates were 89.3% for ALT and 88.8% for AST. Older adults were somewhat more likely to have ALT and AST testing if they were dually enrolled in Medicaid (relative risk 1.01, 95% confidence interval [CI] 1.00 to 1.02) or had multiple chronic conditions (relative risk 1.03, 95% CI 1.00 to 1.06 for 2 to 3 conditions; odds ratio [OR] 1.08, 95% CI 1.05 to 1.11 for 4 to 5 conditions; OR 1.14, 95% CI 1.11 to 1.17 for 6+ conditions), compared with 0 to 1 conditions. Non-Hispanic blacks were less likely to receive baseline testing (OR 0.97, 95% CI 0.96 to 0.98) than non-Hispanic Whites, and male beneficiaries were somewhat less likely to receive testing than female beneficiaries (OR 0.99, 95% CI 0.98 to 0.99). Abnormal values were rare. In conclusion, ALT and AST assessment after statin initiation was commonly done as recommended, and there were negligible disparities in testing rates for beneficiaries.