Natural history of benign prostatic hypertrophy and acute urinary retention.

Twenty-six patients with prostatism due to benign prostatic hypertrophy were evaluated prospectively every three to six months for three years. Using both subjective and objective criteria significant deterioration was demonstrated. The rate of deterioration appeared independent of prostatic size. In the individual patient progression was variable. More than half of the patients were unchanged or improved after two years. Acute urinary retention appeared independent of the degree of prostatism and therefore unpredictable. The methods can be used to evaluate medical treatments of benign prostatic hypertrophy.