title: Urinary Neurotrophin Levels Increase in Women With Stress Urinary Incontinence After a Midurethral Sling Procedure.
abstract: OBJECTIVE
  To investigate the association between urinary neurotrophin levels, maximum flow rate (Qmax) variation, and the appearance of urgency in women with stress urinary incontinence (SUI) after a midurethral sling (MUS) procedure.
  
  
  METHODS
  Thirty-one women with SUI were treated with a MUS. One year later, the outcome of surgery and the onset of urgency were assessed. At baseline and 1-year follow-up, urine was collected to measure nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) concentration, and Qmax variation was calculated. Urine samples from healthy women (n = 20) without lower urinary tract symptoms and overactive bladder (OAB) wet patients (n = 32) were used as controls. Urinary neurotrophin levels were measured by enzyme-linked immunosorbent assay and normalized to creatinine concentration.
  
  
  RESULTS
  At baseline, urinary levels of NGF and BDNF were similar between SUI and healthy women (NGF: 2.10 ± 0.68 vs 1.99 ± 1.05; BDNF: 1.99 ± 0.71 vs 1.81 ± 0.90), and significantly inferior to OAB wet patients (NGF: 2.10 ± 0.68 vs 2.50 ± 0.54, P < .05; BDNF: 1.99 ± 0.71 vs 2.71 ± 0.45, P < .05). After surgery, there was a significant increase of both neurotrophins (vs baseline, P < .05) to the values of OAB wet patients. Moreover, there was a significantly higher percentage increase of NGF in women with de novo urgency than in those without lower urinary tract symptoms (P = .019). A trend for a higher mean Qmax reduction in women with de novo urgency was also found (P = .085).
  
  
  CONCLUSIONS
  These findings suggest that increased bladder outlet resistance after a MUS may play a key role in the rise of urinary neurotrophins, promoting sensitization of bladder primary afferents and causing de novo urgency in susceptible patients.
authors.affiliation: Department of Urology, Hospital de S. João, Porto, Portugal; Faculty of Medicine, University of Porto, Portugal; I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal. Electronic address: tiagoantuneslopes@gmail.com.
authors.forename: Tiago
authors.initials: T
authors.lastname: Antunes-Lopes
authors.affiliation: I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal; Department of Experimental Biology, Faculty of Medicine, University of Porto, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Coelho
authors.affiliation: Department of Urology, Hospital de S. João, Porto, Portugal; Faculty of Medicine, University of Porto, Portugal; I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal.
authors.forename: Rui
authors.initials: R
authors.lastname: Pinto
authors.affiliation: I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal; Department of Experimental Biology, Faculty of Medicine, University of Porto, Portugal.
authors.forename: Sérgio C
authors.initials: SC
authors.lastname: Barros
authors.affiliation: I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal; Department of Experimental Biology, Faculty of Medicine, University of Porto, Portugal.
authors.forename: Célia D
authors.initials: CD
authors.lastname: Cruz
authors.affiliation: Department of Urology, Hospital de S. João, Porto, Portugal; Faculty of Medicine, University of Porto, Portugal; I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal.
authors.forename: Francisco
authors.initials: F
authors.lastname: Cruz
authors.affiliation: Department of Urology, Hospital de S. João, Porto, Portugal; Faculty of Medicine, University of Porto, Portugal; I3S - Instituto de Inovação e Investigação em Saúde, IBMC - Institute for Molecular and Cell Biology, University of Porto, Portugal.
authors.forename: Carlos M
authors.initials: CM
authors.lastname: Silva
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000652:urine; D019208:Brain-Derived Neurotrophic Factor / Q000652:urine*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008875:Middle Aged; D020932:Nerve Growth Factor / Q000652:urine*; D010865:Pilot Projects; D011184:Postoperative Period; D053825:Suburethral Slings; D016482:Urinalysis; D001743:Urinary Bladder / Q000503:physiopathology; D014550:Urinary Incontinence, Stress / Q000503:physiopathology / Q000601:surgery / Q000652:urine*; D014563:Urodynamics / Q000502:physiology*
chemical_list: D015415:Biomarkers; D019208:Brain-Derived Neurotrophic Factor; C579455:BDNF protein, human; D020932:Nerve Growth Factor