Data do not support the use of elevated urinary nerve growth factor and fractalkine levels as diagnostic and prognostic biomarkers for women with overactive bladder

Abstract

Objective: This study investigated urinary nerve growth factor (NGF) and fractalkine levels in women with overactive bladder (OAB), as well as diagnostic and/or prognostic roles, and correlation of these urinary biomarkers with symptom severity of patients.

Materials and Methods: Twenty-seven women with OAB and 26 healthy subjects were enrolled. Patients were diagnosed with OAB based on symptoms, a 3-day voiding diary and a validated Turkish version of the Overactive Bladder-Validated 8 (OAB-V8) questionnaire. The urinary baseline levels of NGF and fractalkine were compared between OAB patients and control group. The Turkish-validated International Consultation on Incontinence Questionnaire Short Form and OAB-V8 used to categorize patients according to disease severity to assess treatment efficacy. Further urinary NGF and fractalkine levels were compared before and after antimuscarinic treatment.

Results: Urinary NGF/creatinine (Cr) and fractalkine/Cr were significantly elevated in OAB patients (0.40 ± 0.40 ng/mg and 4.63 ± 4.36 ng/mg, respectively) compared to healthy subjects (0.14 ± 0.08 ng/mg and 2.00 ± 1.29 ng/mg, P = 0.002 and P = 0.005, respectively). Sensitivity and specificity were 85.2%, 65.4% for NGF, and 74.1%, 65.4% for fractalkine, respectively. No significant differences in NGF/Cr and fractalkine/Cr compared to baseline (P = 0.063 and 0.162, respectively) were observed after trospium chloride treatment in OAB patients. NGF/Cr and fractalkine/Cr exhibited no correlations with symptom severity levels.

Conclusions: Increased urinary NGF/Cr and fractalkine/Cr levels were found in OAB women. However, the sensitivity and specificity were not sufficient for diagnostic use. NGF and fractalkine levels were decreased after treatment insignificantly, and there was no correlation with symptom severity; therefore their prognostic worth was limited.