Gabapentenoids in pain management in urological chronic pelvic pain syndrome: Gabapentin or pregabalin?

To compare efficacy of gabapentin and pregabalin in patients with urological chronic pelvic-pain syndrome (UCPPS).

Design-retrospective, setting-urology outpatient services of a secondary-care private hospital, inclusion criteria-men 18-50 years, presenting with pelvic pain (lower abdomen, groin, scrotum, perineum, low-back, hip) with or without lower urinary tract symptoms for at least 3 months duration. Hospital database was searched using keywords for neuropathic pain (ICD9-729.2, 719.45) and prostatitis (ICD9-601.1, 601.9). Clinical data were retrieved from patient-records, laboratory and radiology data, and analyzed using SPSS-19 statistical software.

Between Mar 2013 and Oct 2015, data of consecutive 119 patients fulfilling the above criteria was analyzed. Median age of patients was 35 years (IQR 29-43) and median duration of symptoms 12 months (IQR 6-24 months). Before treatment median VAS (0-10) pain score was 5 (IQR 4-6). Gabapentin was significantly more effective in controlling pain compared to pregabalin. Three fourth of patients on gabapentin alone (47/62) reported at least 50% improvement in pain compared to only 40% on pregabalin alone (12/30) (P = 0.0012; χ(2)  = 9.765. NNT 2.9, 95%CI 1.8-6.5). Twenty patients who were initially put on pregabalin had to switch to gabapentin for lack of efficacy. Forty four percent of patients on pregabalin required amitriptyline (24/54) compared to only 13.6% of those on gabapentin (10/72) required the same (P value of difference 0.0001; χ(2)  = 14.622. NNT 4, CI 95% 2.2-6.6).

Gabapentin may be more effective than pregabalin in UCPPS.

Neurourology and urodynamics. 2017 Feb 10 [Epub ahead of print]

Mayank Mohan Agarwal, Mudelin Elsi Sy

Department of Urology, NMC Specialty Hospital, Abu Dhabi, United Arab Emirates.