To identify metabolites that are associated with an overactive bladder (OAB) using metabolomics.
A total of 58 males without apparent neurological disease completed 24-hr bladder diaries of their micturition behavior and International Prostate Symptom Score (IPSS) for the assessment of micturition behavior and lower urinary tract symptoms. Urgency was defined as an IPSS urgency score of ≥2 (OAB group), and patients with IPSS urgency scores of ≤1 belonged to the control group. A comprehensive study of plasma metabolites was also conducted using capillary electrophoresis time-of-flight mass spectrometry. Metabolite levels were compared between the control and OAB groups using the Mann-Whitney U test. Potential metabolite biomarkers were selected using multivariate logistic regression analysis.
Of the 58 subjects, the control and OAB groups consisted of 32 and 26 males, respectively. Nocturnal urinary volume, 24-hr micturition frequency, nocturnal micturition frequency, and the nocturia index were significantly higher in the OAB group. Metabolomic analysis revealed 60 metabolites in the subjects' plasma. The levels of 11 metabolites differed between and the control and OAB groups. Multivariate analysis showed that an increased glutamate level and reduced arginine, glutamine, and inosine monophosphate levels are significantly associated with OAB in males. Reduced levels of asparagine and hydroxyproline could also be associated with OAB.
Urgency is associated with abnormal metabolism. Analyses of amino acid profiles might aid the search for new treatment targets for OAB.
Urology. 2018 May 09 [Epub ahead of print]
Hiroshi Shimura, Takahiko Mitsui, Satoru Kira, Tatsuya Ihara, Norifumi Sawada, Hiroshi Nakagomi, Tatsuya Miyamoto, Sachiko Tsuchiya, Mie Kanda, Masayuki Takeda
Department of Urology, University of Yamanashi Graduate School of Medical Sciences., Department of Urology, University of Yamanashi Graduate School of Medical Sciences. Electronic address: .