Primary nocturnal enuresis persistent to adulthood, functional evaluation

Introduction and Objectives: The incidence of nocturnal enuresis (NE) in adults (over 18 years of age) ranges from 0.5 to 2% for most authors. NE is a multifactorial disease. Lack of circadian rhythm of antidiuretic hormone (ADH) is one of the commonly accepted causes, however, disorders affecting bladder function is another important pathophysiologic factor that has not been settled. The target of the present study is to define bladder function in adults having persistent NE. Methods: Fifty two adult patients were included. Mean age was 23.6 +/- 6.9 years. All of them had primary NE persistent to adulthood. No treatment was received within 2-7 days prior to the urodynamic examination. All of them had intact neuro-urological examination. Filling (in all patients) and voiding cystometry (in 29 patients) were carried out, using 8 F urodynamic and 8 F rectal catheters. Pressure flow analysis was interpreted using Schafer's nomogram. Results: Overall mean maximum cystometric capacity was 419.2 +/- 142 ml, mean bladder compliance was 51.3 +/- 39.7 ml/cmH(2)O. In males (n = 25), mean maximum cystometric capacity was 453 173 ml and compliance was 56 +/- 42 ml/cmH(2)O, while in females (n = 27), mean capacity was 388 +/- 98 ml and compliance was 46.7 +/- 36.7 ml/cmH(2)O. Twenty patients had detrusor instability (38.5%). Twelve out of 27 (44.4%) females had instability while only 8 out of 25 (32%) males had the same finding. Differences relevant to maximum bladder capacity and compliance between the patients with and without instability were significant (P < 0.0001). Mean detrusor opening pressure was 55.3 +/- 25 cMH(2)O, mean detrusor pressure at maximum flow and maximum detrusor pressure, were 53.5 +/- 21 and 78.9 +/- 35 cmH(2)O respectively. Conclusions: Urodynamic studies in adults with persistent NE reveals a relatively high incidence of instability, normal capacity and compliance. The presence of instability was associated with smaller bladder and poorer compliance and with diurnal urgency. Voiding bladder function in adult enuretics was found to be normal. (C) 2003 Wiley-Liss, Inc.