title: Overactive bladder changes with time: a 5-year longitudinal followup of changes in overactive bladder symptoms, urodynamic studies and urinary nerve growth factor levels.
abstract: OBJECTIVE
  We compared clinical symptoms, urodynamic diagnoses and urinary nerve growth factor levels at baseline and 5 years later in patients with overactive bladder.
  
  
  METHODS
  Patients diagnosed with overactive bladder at a tertiary teaching hospital who underwent urinary nerve growth factor tests 5 years previously were identified by chart review. Patients were invited to return for symptom evaluation, urodynamic studies and a repeat urinary nerve growth factor test. Changes in overactive bladder subtype, urgency severity score and urodynamic diagnosis were classified as improved, stable or worse. Changes in urinary nerve growth factor/creatinine were compared between baseline and 5 years later according to changes in bladder conditions.
  
  
  RESULTS
  A total of 30 women and 45 men completed the study. Mean±SD age was 73.5±10.3 years. Urinary nerve growth factor/creatinine showed no significant difference among patients with improved, stable or worse bladder conditions based on overactive bladder or urgency severity score subtypes. However, urinary nerve growth factor/creatinine was significantly decreased in patients with an improved urodynamic diagnosis (mean 0.94±1.36 vs 0.17±0.19 pg/mg, p=0.02), significantly increased in patients with a worse urodynamic diagnosis (0.55±0.85 vs 2.08±2.81 pg/mg, p=0.04) and showed no change in those with a stable urodynamic diagnosis. Multiple linear regression analysis revealed that the change in urodynamic diagnosis was still predictive of the change in urinary nerve growth factor/creatinine after adjusting for age, gender, overactive bladder and urgency severity score subtypes (p=0.001).
  
  
  CONCLUSIONS
  Urinary nerve growth factor/creatinine did not reflect the changes in bladder conditions based on subjective symptoms. However, the levels reflected dynamic changes in bladder pathophysiology according to urodynamic findings.
authors.affiliation: Department of Obstetrics and Gynecology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan, Republic of China.
authors.forename: Fei-Chi
authors.initials: FC
authors.lastname: Chuang
authors.affiliation: Department of Urology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, Republic of China; Institute of Pharmacology and Toxicology, Tzu Chi University, Hualien, Taiwan, Republic of China.
authors.forename: Hsin-Tzu
authors.initials: HT
authors.lastname: Liu
authors.affiliation: Department of Medicine, Mackay Medical College, New Taipei City, Taiwan, Republic of China.
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Wang
authors.affiliation: Department of Urology, Buddhist Tzu Chi General Hospital, Hualien, Taiwan, Republic of China; Department of Urology, Tzu Chi University, Hualien, Taiwan, Republic of China. Electronic address: hck@tzuchi.com.tw.
authors.forename: Hann-Chorng
authors.initials: HC
authors.lastname: Kuo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D020932:Nerve Growth Factor / Q000652:urine*; D013997:Time Factors; D053201:Urinary Bladder, Overactive / Q000175:diagnosis* / Q000503:physiopathology / Q000652:urine*; D014563:Urodynamics
chemical_list: D020932:Nerve Growth Factor
keywords: creatinine; muscle hypertonia; nerve growth factor; overactive; urinary bladder; urodynamics