Racial Differences in the Association Between Preoperative Serum Cholesterol and Prostate Cancer Recurrence: Results from the SEARCH Database.

BACKGROUND: Black men are disproportionately affected by both cardiovascular disease and prostate cancer. Epidemiologic evidence linking dyslipidemia, an established cardiovascular risk factor, and prostate cancer progression is mixed. As existing studies were conducted in predominantly non-black populations, research on black men is lacking.
METHODS: We identified 628 black and 1,020 non-black men who underwent radical prostatectomy and never used statins before surgery in the Shared Equal Access Regional Cancer Hospital (SEARCH) database. Median follow-up was 2.9 years. The impact of preoperative hypercholesterolemia on risk of biochemical recurrence was examined using multivariable, race-stratified proportional hazards. In secondary analysis, we examined associations with low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides, overall and among men with dyslipidemia.
RESULTS: High cholesterol was associated with increased risk of recurrence in black [HR(per10 mg/dL) 1.06; 95% confidence interval (CI), 1.02-1.11] but not non-black men (HR(per10 mg/dL) 0.99; 95% CI, 0.95-1.03; P(interaction) = 0.011). Elevated triglycerides were associated with increased risk in both black and non-black men (HR(per10 mg/dL) 1.02; 95% CI, 1.00-1.03 and 1.02; 95% CI, 1.00-1.02, respectively; P(interaction) = 0.458). There were no significant associations between LDL or HDL and recurrence risk in either race. Associations with cholesterol, LDL, and triglycerides were similar among men with dyslipidemia, but low HDL was associated with increased risk of recurrence in black, but not non-black men with dyslipidemia (P(interaction) = 0.047).
CONCLUSION: Elevated cholesterol was a risk factor for recurrence in black but not non-black men, whereas high triglycerides were associated with increased risk regardless of race. IMPACT: Significantly contrasting associations by race may provide insight into prostate cancer racial disparities. ©2016 American Association for Cancer Research.