抄録
Objectives: Hypertension and benign prostatic hyperplasia (BPH) can be major factors contributing to the occurrence of nocturia. Hypertension caused by an increase of daytime catecholamine levels would decrease renal blood flow, leading to insufficient daytime urine production. A relatively low levels of catecholamines at night would increase renal blood flow, allowing urine production to increase in order to excrete water stored during the daytime. The other main cause of nocturia is a low nocturnal bladder capacity due to BPH in male patients. Although doxazosin, a subtype nonselective α1-adrenoceptor antagonist, has been shown to improve hypertension and BPH, it is recommended that the 2 disease entities should be treated independently with the best available drugs. Therefore, we compared the efficacy and safety of 3 α1-adrenoceptor antagonists with different selectivity for the α1-adrenoceptor subtypes for nocturia in male patients with hypertension and BPH.
Methods: In a retrospective study, the medical records of 58 hypertensive patients with BPH treated with doxazosin, silodosin plus amlodipine, or tamsulosin plus amlodipine between January 2013 and December 2015 were evaluated. Overactive Bladder Symptom Score (OABSS), International Prostate Symptom Score (I-PSS), QOL score and maximum urinary flow rate were assessed at baseline and after a 12-week treatment period in all patients.
Results: Treatment with doxazosin and amlodipine resulted in a significant reduction in blood pressure from baseline. Doxazosin, silodosin and tamsulosin were similarly effective in improving total I-PSS, QOL score and maximum urinary flow rate. However, the changes in total OABSS and nocturia (Q2 score in OABSS) from baseline to 12 weeks were significantly greater with doxazosin than with the other 2 drugs. Although dizziness was reported in 1 of the 21 patients receiving doxazosin, abnormal ejaculation was reported with subtype selective α1-adrenoceptor antagonists but not with doxazosin.
Conclusions: Although all 3 α1-adrenoceptor antagonists have similar clinical efficacy, doxazosin may be more effective to improve storage symptoms such as nocturia. Furthermore, our data demonstrate that there are slight differences in the adverse event profiles of these drugs. These findings suggest that doxazosin is a safe and effective treatment for nocturia in hypertensive patients with BPH.
