Poor Glycemic Control is Associated with Reduced Prostate Specific Antigen Concentrations in Men with Type 1 Diabetes

Abstract

Previous studies have revealed lower prostate specific antigen concentrations in men with type 2 diabetes, paralleling the reported lower prevalence of prostate cancer in diabetic men. Data are lacking on prostate specific antigen in men with type 1 diabetes whose insulin and obesity profiles differ from those with type 2 diabetes mellitus. In this study we examined the relationship between long-term glycemic control and prostate specific antigen in men with type 1 diabetes mellitus. Total prostate specific antigen was measured at one time in 639 men in the EDIC, the observational followup of participants in the DCCT. The relationship between DCCT/EDIC weighted mean hemoglobin A1c and log prostate specific antigen was assessed using linear regression modeling after adjusting for age, body mass index, total testosterone, statin and thiazide medication use, diabetes duration, and DCCT randomization arm and cohort. Median subject age was 52 years, body mass index was 28.4 kg/m(2) and DCCT/EDIC time-weighted hemoglobin A1c was 7.9%. Median prostate specific antigen was 0.64 ng/ml (IQR 0.43, 1.05). Prostate specific antigen increased significantly with age (p <0.0001) and with lower time-weighted hemoglobin A1c (p <0.0001). Each 10% increase in hemoglobin A1c was accompanied by an 11% reduction in prostate specific antigen (p=0.0001). Prostate specific antigen decreases as hemoglobin A1c increases in men with type 1 diabetes mellitus. This relationship is independent of age, body mass index, androgen levels, medication use and measures of diabetes severity, which suggests that factors related to glycemia may directly affect prostate specific antigen levels.