Evaluation of the relationship of cholinergic metabolites in urine and urgency urinary incontinence

INTRODUCTION AND HYPOTHESIS: To investigate differences in urine cholinergic metabolites in women with urinary urgency incontinence (UUI) and responders (R) and non-responders (NR) to anti-cholinergic medications (AC). METHODS: Patients with UUI and age-matched controls were evaluated pre- and post-treatment using OABSS, UDI-6 and IIQ-7. Controls were defined as having a cumulative OABSS of zero. Patients with UUI were treated with AC and followed for 12 weeks. Responders were those with a > 50% decrease in the total OABSS score. Urine samples were collected from all participants for evaluation. Metabolite detection was accomplished using commercial assay kits. Wilcoxon-rank sum test and Fisher’s exact test were used to express differences between groups. Spearman’s rho correlation coefficient was used to determine the relationship between acetylcholine (Ach), choline (Ch), acetylcholinesterase (AchE) and questionnaire scores. RESULTS: We recruited 39 with UUI and 33 controls. We found concentrations of Ch [29.0 (IQR: 24.2–42.5) μmol vs. 15.2 (IQR: 7.5–24.1) μmol] and Ach [65.8 (IQR: 30.4–101.8) nmol and 33.1 (IQR: 11.9–43.8) nmol] were higher in the UUI group compared to controls (p = 0.003 and p < 0.001, respectively] and no differences in AchE concentrations. In the UUI group, 43.6% responded to AC after 12 weeks of therapy. There were no differences in Ch or AchE levels between R and NR; Ach levels were higher in the R group [82.1 nmol (IQR: 54.8–118.1) vs. 50.3 nmol (IQR: 29.9–68.2), p = 0.007]. Ch and Ach were positively associated with pre-treatment OABSS parameters. CONCLUSIONS: Urine Ach is higher in responders to anti-cholinergic therapy, and urine cholinergic metabolites were higher in the UUI patients compared to controls.