Elevated PSA Levels Raise Questions

Two of my patients are older men (aged 62 years and 68years) who have benign prostatic hyperplasia; their prostatesare soft and nontender. Recent prostate-specific antigen(PSA) measurements revealed elevated levels-from 3.5 to4.4 ng/mL in the 62-year-old man and from 4.2 to 5.8ng/mL in the 68-year-old man. Both patients had takensildenafil and had sexual intercourse the day before the examination.Could the elevations in their PSA levels be aneffect of sildenafil? If so, how long does this effect persist?

-Leonard B. Beller, MD
  Los Angeles

PSA levels can vary throughout the day. There is noevidence that sildenafil, without sexual intercourse,alters these levels.

However, the results of a number of trials suggestthat intercourse may affect PSA values. Mycolleagues and I conducted a study that showed intercoursehad no effect in men with normal baseline levelsbut was associated with increased PSA values in men whohad an elevated baseline measurement.¹ I have also foundthat bicycle riding and digital rectal examinations do notaffect PSA levels.^2,3

Therefore, I believe the degree of change seen inyour patients warrants further investigation. The normalPSA level for men of this age is less than 3 ng/mL.

-

E. David Crawford, MD
  Professor of Surgery and Radiation Oncology
  University of Colorado
  Denver

REFERENCES:1. Stenner J, Hathaus K, MacKenzie SH, Crawford ED. The effect of ejaculationon prostate specific antigen in a prostate cancer screening population. Urology.1998;51:455-459.
2. Safford HR, Crawford ED, MacKenzie SH, Capriola M. The effect of bicycleriding on serum prostate specific antigen levels. J Urol. 1996;156:103-105.
3. Crawford ED, Schutz MJ, Clefan S, et al. The effect of digital rectal examinationon prostate specific antigen levels. JAMA. 1992;267:2227-2228.