The presence of Fowler's syndrome predicts successful long-term outcome of sacral nerve stimulation in women with urinary retention.
OBJECTIVE
Sacral nerve stimulation (SNS) is an effective treatment for women with urinary retention. Some women present specific electromyography abnormalities of the external urethral sphincter (Fowler's syndrome). The aim of this study was to evaluate whether Fowler's syndrome and psychologic preimplant screening could be predictive factors for long-term success of SNS in women with urinary retention.


METHODS
All patients underwent electrophysiologic and urodynamic studies and voiding charts. A validated psychologic screening questionnaire was used. Women with successful temporary stimulation, received a definitive implant (Interstim Medtronic). They were followed prospectively every 6 months. Failure was defined as recurrent retention needing intermittent or permanent catheterisation.


RESULTS
Sixty-two women were implanted, 30 with Fowler's syndrome, 32 with idiopathic retention. In those with Fowler's syndrome, 26.6% screened positive for somatisation, as did 43.8% in the idiopathic group (not significant [ns]). Screening for depression was positive in 30% and 18.8%, respectively (ns). There was no correlation with outcome. Twenty-eight patients failed: 9 with Fowler's syndromes, 19 without (p=0.04). Kaplan-Meier analysis showed that patients with Fowler's syndrome benefitted significantly longer from SNS (log-rank test, p=0.005).


CONCLUSIONS
The presence of Fowler's syndrome is a positive predictive factor for SNS in female urinary retention. Idiopathic urinary retention patients can benefit as well, but the success might be less predictable. Preimplant psychologic screening, using the Patient Health Questionnaire, does not correlate with long-term outcome of SNS in this population.
De Ridder
Dirk
D
Department of Urology, University Hospitals KU Leuven, Leuven, Belgium. dirk.deridder@uz.kuleuven.ac.be
Ost
Dieter
D
Bruyninckx
Frans
F
D004599:Electric Stimulation Therapy; D004567:Electrodes, Implanted; D004576:Electromyography; D005073:Evoked Potentials, Somatosensory; D005260:Female; D006801:Humans; D008160:Lumbosacral Plexus; D008875:Middle Aged; D011594:Psychometrics; D013577:Syndrome; D014521:Urethra / Q000503:physiopathology; D016055:Urinary Retention / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D014563:Urodynamics