Urinary neurotrophic peptides in postmenopausal women with and without overactive bladder.

AIMS: The aim of this study was to compare the expression of urinary nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), substance P (SP), and calcitonin-gene related peptide (CGRP) in women with and without overactive bladder (OAB). We sought to determine factors associated with higher expression of these neuropeptides.

METHODS: Participants with OAB and age-matched controls were enrolled. Symptom severity was assessed with validated questionnaires. Urinary neurotrophin levels, symptom scores, and clinical data were compared between the groups. Multivariate analysis determined independent factors associated with urinary neurotrophin levels.

RESULTS: Sixty-seven women (38 OAB, 29 controls) were included. Women with OAB and controls were similar in age, race, body mass index, parity, and smoking status. Women with OAB were more likely to report a history of pelvic pain and pelvic surgery. Neurotrophic factor levels normalized to urinary creatinine did not differ between the groups. Increasing age was associated with greater urinary levels of BDNF and NGF (β = 0.23, 95%CI 0.11-0.34 and 0.75, 95%CI 0.17-1.33, respectively, P < 0.02). Higher urinary NGF was associated with increasing BMI (β = 0.81, 95%CI 0.05-1.57, P = 0.04) while pain was associated with elevated urinary SP (β = 0.21, 95%CI 0.09-0.33, P = 0.001).

CONCLUSIONS: Our data does not support a relationship between urinary neurotrophin levels and OAB in age-matched postmenopausal women. Further research is necessary to elucidate the role of urinary neurotrophins in the diagnosis and management of OAB. Neurourol. Urodynam. 36:740-744, 2017. © 2016 Wiley Periodicals, Inc.