[The doxazosin treatment of the changes in the bladder filling phase in benign prostatic hyperplasia]

To analyze the clinical and urodynamic efficacy of treatment with doxazosin during 6 months for bladder filling phase disorders in patients with BPH.

A prospective clinical and urodynamic study was performed in 65 males with BPH, aged 54-79 years (mean 66.7), who had been treated with doxazosin (4 mg/day) during 6 months. Clinical [International Prostatic Symptom Score (IPSS)] and urodynamic evaluations (cystometry and filling cystography) before and after treatment were performed. IPSS data were obtained according to the WHO recommendation following validation and translation into Spanish.

The IPSS score improved significantly from 19.8 +/- 4.8 before treatment to 11.9 +/- 4.6 after treatment (p < 0.001). All the patients were normotensive before and after treatment (systolic and diastolic blood pressures 135.9/78.9 and 135.4/77.8 mmHg, respectively). No tachycardia was observed before (71.9 +/- 5.8) or after treatment (71.8 +/- 5.9). A relationship between the lower IPSS before treatment and urinary symptoms improvement was demonstrated (coef.-0.45939). We found no relationship between prostate volume (digital rectal examination or transabdominal ultrasonography) and IPSS modifications after treatment. Bladder instability decreased significantly from 71.6% before treatment to 33.3% after treatment (p < 0.01). Instability pressure also diminished from 99.2 cms H2O to 60.3 cms H2O after doxazosin treatment (p < 0.001). We found no significant relationship between IPSS and bladder instability post-treatment.

Adrenergic blockade with doxazosin 4 mg/day for 6 months achieves a significant decrease in the bladder instability associated with prostatic obstruction in patients with BPH, although no statistical correlation with the IPSS could be demonstrated.