• nerve growth factor;
  • overactive bladder;
  • menopause;
  • obesity;
  • detrusor overactivity

Study Type – Aetiology (case series)

Level of Evidence 4

What’s known on the subject? and What does the study add?

Urinary nerve growth factor levels were higher in women with OAB-dry and OAB-wet compared to the controls. The link between female OAB and risk factors such as obesity and menopause has not been determined yet.

This study found ageing, menopause, or higher BMI did not influence the urinary NGF levels in OAB women. Higher urinary NGF levels in OAB women could be an inflammatory disorder unrelated to ageing or obesity.


• To measure urinary nerve growth factor (NGF) in women with overactive bladder (OAB)-dry and OAB-wet and investigate the association of urinary NGF expression with these factors.


• Differentiation between OAB-wet and OAB-dry was based on symptoms and a 3-day voiding diary.

• Urinary NGF levels were measured by enzyme-linked immunosorbent assay (ELISA).

• The urinary NGF levels were compared among controls, OAB-dry and OAB-wet subgroups, and also between OAB patients ≥55 years and <55 years, as well as between patients with a body mass index (BMI, kg/m2) <20, 20–30 and >30.


• A total of 113 women with OAB-dry, 106 with OAB-wet and 84 controls were enrolled. The urinary NGF/creatinine (Cr) levels were significantly highest in OAB-wet (2.13 ± 3.87) and second highest in OAB-dry (0.265 ± 0.59) compared to controls (0.07 ± 0.21).

• Analysis of urinary NGF or NGF/Cr levels among controls, OAB-dry and OAB-wet groups by age and BMI showed no significant differences, except for the OAB-dry group.

• Urinary NGF/Cr was not significantly correlated with age (P= 0.088) or BMI (P= 0.886) in women with OAB-dry and OAB-wet.


• Urinary NGF levels were significantly higher in women with OAB-dry and even higher in women with OAB-wet.

• The urinary NGF level was not associated with ageing, menopause or higher BMI either in controls or OAB patients.