The association of endothelial nitric oxide synthase (eNOS) G894T gene polymorphism with responsiveness to a selective α1 -blocker in men with benign prostatic hyperplasia related lower urinary tract symptoms.

Abstract

To prospectively investigate the association of endothelial nitric oxide synthase (eNOS) G894T gene polymorphism with responsiveness to a selective α1 -blocker in men with benign prostatic hyperplasia related lower urinary tract symptoms (BPH/LUTS), as nitric oxide has recently gained increasing recognition as an important neurotransmitter of functions in the lower urinary tract. In all, 136 men with BPH/LUTS were recruited from urology outpatient clinics in a university hospital. Oral therapy with doxazosin gastrointestinal therapeutic system (GITS) 4 mg once-daily was given for 12 weeks. The drug efficacy was assessed by the changes from baseline in the total International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax ) and post-void residual urine volume (PVR) at 12 weeks of treatment. The 'responders' to doxazosin GITS were defined as those who had a total IPSS decrease of >4 points from baseline. eNOS G894T polymorphism was determined using the polymerase chain reaction-restriction fragment length polymorphism method. Patients had statistically significant improvements in total IPSS, quality of life score, and Qmax (P < 0.01) after a 12-week period of treatment. Using multiple logistic regression analysis adjusted for age and IPSS, our results showed that being a eNOS 894T allele carrier was an independent risk factor for being a drug non-responder (P = 0.03, odds ratio 4.19). Moreover, a decreased responder rate (P = 0.01), as well as the lower improvements in IPSS (P = 0.02) and Qmax (P = 0.03) were significantly associated with increment in the T allele number. The presence of the eNOS 894T allele had a significantly negative impact on responsiveness to a selective α1 -blocker in BPH/LUTS treatment, suggesting that eNOS G894T gene polymorphism may be a genetic susceptibility factor for α1 -blocker efficacy in men with BPH/LUTS.