A prospective study of statin use and mortality among 67,385 blacks and whites in the Southeastern United States

Abstract

Loren Lipworth,1 Sergio Fazio,1,2 Edmond K Kabagambe,1 Heather M Munro,3 Victor C Nwazue,1 Robert E Tarone,3 Joseph K McLaughlin,3 William J Blot,1,3 Uchechukwu KA Sampson1,2,41Department of Medicine, Vanderbilt University Medical Center, 2Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, USA; 3International Epidemiology Institute, Rockville, MD, USA; 4Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USAPurpose: The primary objective of this study is to examine the race-specific associations between statin use and overall mortality, as well as cardiovascular and cancer mortality, among blacks and whites in the Southeastern United States (US). Little is known about these associations in blacks.Patients and methods: The Southern Community Cohort Study is an ongoing, prospective cohort study, which enrolled from 2002 through 2009 nearly 86,000 participants aged 40–79 years. We used Cox regression models to estimate race-specific hazard ratios (HRs) and 95% confidence intervals (CI) for overall and cause-specific mortality associated with statin use based on self-reported hypercholesterolemia and treatment at cohort entry. Mean age at cohort entry was 51.4 years in blacks (n=48,825) and 53.5 years in whites (n=18,560). Sixty-one percent of participants were women. Whites were more likely to have self-reported hypercholesterolemia (40% versus 27%, P<0.001), and to report being treated with either statins (52% versus 47%, P<0.001) or combination lipid therapy (9% versus 4%, P<0.001) compared with blacks, regardless of sex. During follow-up (median: 5.6 years) 5,199 participants died. Compared with untreated hypercholesterolemic individuals, statin use was associated with reduced all-cause mortality (adjusted HR [aHR] 0.86; 95% CI 0.77–0.95) and cardiovascular disease mortality overall (aHR 0.75; 95% CI 0.64–0.89) and among whites (aHR 0.67; 95% CI 0.50–0.90), blacks (aHR, 0.80; 95% CI 0.65–0.98), men (aHR 0.70; 95% CI 0.55–0.90), and women (aHR 0.79; 95% CI 0.63–0.99) (P>0.05 for race and sex interaction). Statin use was not associated with cancer mortality overall or in subgroup analyses.Conclusion: Regardless of race or sex, self-reported statin use was linked to reduced all-cause and cardiovascular disease mortality. However, factors contributing to the modestly lower statin use and markedly lower prevalence of self-reported hypercholesterolemia among blacks remain to be determined.Keywords: statins, disparities, hypercholesteromia, undertreatment, underdiagnosis, mortality