Placebo and BPH

Clinical bottom line

Improvement in symptom scores and urinary flow rate occur without effective treatment, but prostate volume was a big factor, with lesser effects in men with larger prostates. Impotence, lack of libido, acute retention, surgery, and prostate cancer will occur without treatment.

Reference

JC Nickel. Placebo therapy of benign prostatic hyperplasia: a 25-month study. British Journal of Urology 1998 81: 383-387.

Study

This study examined the result of placebo therapy over 25 months in 303 men randomised to the placebo arm of a clinical trial. At entry men had be younger than 80 years, with a maximum urinary flow rate of 5-15 mL/second, at least two moderate symptoms of BPH but nor more than two severe symptoms, an enlarged prostate gland detected by digital examination and a PSA of less than 10 ng/mL.

Results

At baseline the mean age was 64 years, the maximum urinary flow rate was 10 mL/second and the prostate volume was 46 mL.

The urinary flow rate was significantly better than baseline at every visit over the 25 months of the study, by about 1-1.5 mL/second.
The symptom score improved for the first two months, and then worsened. Those with worse symptoms responded more. Those with a prostate volume of 40 mL or less had a greater response than those with a larger prostate volume.
Prostate volume increased progressively and was 8% higher than baseline at the final assessment.
Adverse events were reported in 81% of men, with 6% reporting impotence and 6% reporting decreased libido.
Acute urinary retention occurred in 3.3% of men and 9% had some form of urinary intervention, usually resection.
Prostate cancer was diagnosed in 2% of men.

Comment

This interesting study gives an important insight into what happens when you do nothing in BPH. The improvement in symptom scores and urinary flow rate may be an example of regression to the mean, but prostate volume was a big factor, with lesser effects in men with larger prostates.

Impotence, lack of libido, acute retention, surgery, and prostate cancer will occur without treatment.