Analysis of the prognostic factors for overactive bladder symptoms following surgical treatment in patients with benign prostatic obstruction.

AIMS: To identify the prognostic variables concerning the improvement of overactive bladder syndrome (OAB) related symptoms following a transurethral resection of the prostate (TURP) in patients with benign prostatic obstruction (BPO).
METHODS: A retrospective review was conducted in 298 patients with BPO who had undergone TURP. All patients had completed the preoperative evaluations including OAB related symptoms and full urodynamics, as well as symptomatic assessment postoperatively. OAB related symptoms were defined by the International Prostate Symptom Score questionnaires (questions 2, 4 and 7 stand for frequency, urgency and nocturia). They were divided into three categories based on an individual score >or=3 for on urgency, frequency and nocturia in the preoperative state. The association between the baseline variables and the improvement in each symptom score was analyzed.
RESULTS: A multivariate analysis suggested that the baseline degree of detrusor contractility was consistently associated with the improvement in each OAB symptom (The odds ratio in normal/weak detrusor: 9.5, 3.4, 3.0 for score on urgency, frequency and nocturia, respectively). Both the patient's age (Odds ratio: 0.93) and the maximum flow rate (Odds ratio: 0.20) influenced the improvement in the score on nocturia.
CONCLUSION: The observation of a positive and consistent correlation between the baseline degree of detrusor contractility and the improvement in OAB related symptoms, suggests that good detrusor contractility is essential for the symptomatic benefits after the surgical relief of bladder outlet obstruction. Aging males with good urinary flow rates appear to experience a reduced improvement of nocturia symptoms after undergoing TURP.