Evaluation of the effect of spinal cord injury on serum PSA levels

Objectives. Prostatic structure and secretory activity are thought to be in fluenced by autonomic innervation of the prostate. Prostatic denervation is especially likely in patients with spinal cord injury (SCI) at the level o f the cauda equina or the conus medullaris, where the peripheral nerve supp ly to the prostate may be specifically damaged. This may result in changes in serum prostate-specific antigen (PSA) levels, either directly or indirec tly. Therefore, we measured serum PSA levels and also studied the influence of factors such as age, catheterization, duration of SCI, urinary tract in fection, and history of cystitis on serum PSA values in men with SCI. Methods. Serum PSA levels were determined in 79 men with SCI (age older tha n 40 years) using banked sera by the Abbott MEIA PSA assay. Variables such as age, catheterization, duration of SCI, urine culture results, and histor y of cystitis were obtained from a review of patient records. Comparisons w ere made with a randomly selected, non-SCI control population of 501 men, 4 0 to 89 years old, who underwent serum PSA determination at our institution . Statistical comparisons were performed using the Mann-Whitney U test (non parametric), since the populations were not normally distributed. Multivari ate logistic regression analysis was used to assess the correlation between the various factors and the serum PSA levels in men with SCI. Results. No statistically significant differences were found in the median serum PSA values between the SCI group and the non-SCI control population. The age-specific PSA values obtained in the SCI group were also comparable to those reported for the general population at large. Age (P < 0.03) and t he presence of a catheter (P < 0.0002) were the only two factors that were correlated with higher serum PSA values in the SCI group by regression anal ysis. Conclusions. Men with SCI tended to have serum PSA value distributions that were similar to those of the general population. However, those in the SCI group who had indwelling catheters were more likely to have higher PSA val ues at baseline, as were older men with SCI. UROLOGY 56: 82-86, 2000. (C) 2 000, Elsevier Science Inc.