Background: Several studies have examined serum creatinine as a marker for prostate cancer stage, recurrence, and prognosis. We evaluated whether serum creatinine concentration was associated with risk of developing prostate cancer in a prospective cohort of male smokers.
Methods: A nested case-control study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study of 50- to 69-year-old Finnish men was conducted. Two controls (n = 464) were matched to each case (n = 232) on study center, intervention group, date of baseline blood draw (+/-45 days), and age (+/-5 years). Conditional logistic regression was used to calculate odds ratios and 95% confidence intervals. All P values were two-sided.
Results: Cases had significantly higher prediagnostic serum creatinine concentrations compared with controls (medians of 1.13 versus 1.10 mg/dL, respectively; P = 0.004). Serum creatinine was associated with a significantly greater risk of prostate cancer (multivariate odds ratio, 2.23; 95% confidence interval, 1.33-3.75 for highest versus lowest quartile), with a significant trend (P trend = 0.0008). Exclusion of subjects with a reported history of diabetes, benign prostatic hyperplasia, or hypertension, or whose cancer was diagnosed within the first 5 years of follow-up, did not alter the association. Risk did not differ by disease stage or time from blood draw to diagnosis.
Conclusion: Prospectively measured serum creatinine, within normal ranges, is positively related to prostate cancer risk. Future research should reexamine the association in other populations, including any interrelationship with serum prostate-specific antigen.