Factors influencing variability of PSA blood concentration in patients with prostate benign hyperplasia

: Study conducted in 107 patients with prostate benign hyperplasia to establish the influence that prostate volume, age, sexual activity, extent of obstruction and presence of urethral catheter have on PSA serum levels, using a linear regression model. In simple linear regression studies, a good correlation was seen between PSA serum concentration and prostate volume calculated by transrectal ultrasound (r = 0.57), which decreases when age in used as an independent variable (r = 0.40). In multiple linear regression studies where all the variables are included, correlation increases slightly (r = 0.60), and only prostate volume and sexual activity are significant. Prostate volume in the single most influential factor on PSA levels in prostate benign hypertrophy although it is not the only parameter to be taken into account in serum level variations of this marker. Age influence can be secondary to other factors such as sexual activity.