Influence of age, anthropometry, and hepatic and renal function on serum prostate-specific antigen levels in healthy middle-age men

To test the hypothesis of a causal relationship between clinical parameters, including age, anthropometry, and hepatic or renal function tests and serum prostate-specific antigen (PSA) levels and to determine the predictors of high serum PSA concentrations in healthy middle-age men. Between January 1999 and December 2000, 6005 healthy men 40 to 59 years old who visited our hospital for a routine health checkup were entered into the study. The association between the clinical parameters and a high serum PSA level (greater than 2.5, 3.0, 3.5, or 4.0 ng/mL) was studied in three groups: the 10% with low clinical parameters, the 10% with high clinical parameters, and the remainder as a reference group. The univariate logistic regression analysis indicated that high or low age, body weight, body mass index, creatinine, and creatinine clearance were significant factors in relation to serum PSA concentration compared with the reference group. In the multivariate model used, only older age was positively related to the serum PSA concentration. The results of anthropometry and hepatic and renal function tests do not influence the serum PSA level in this population. Our findings suggest that serum PSA may be a reliable marker in middle-age men without severe hepatic or renal disease.