Evaluation of bladder function and sleep patterns in children with primary mono-symptomatic nocturnal enuresis by polysomnography combined with ambulatory urodynamic monitoring

Abstract

Objective: To evaluate the bladder function and sleep pattern in the children with primary mono-symptomatic nocturnal enuresis (PMNE) by the polysomnography (PSG) and ambulatory urodynamic monitoring (AUM). Methods: From October 2019 to October 2021, forty-three patients with PMNE were selected as PMNE group from the First Affiliated Hospital of Zhengzhou University and further subdivided into the severe PMNE group (enuresis>4 times/week) and the non-severe PMNE group (enuresis times 4 times/week) according to the severity. The conventional urodynamics (CUD), AUM, and PSG examinations and bladder diary were completed in the PMNE group. The control group consisted of 23 children with normal PSG findings and without the lower urinary tract symptoms. Results: The severe PMNE group included 9 males and 14 females, aged(12.1±3.2)years, and nocturnal enuresis number per week is 6.7±1.7. The non-severe PMNE group included 9 males and 11 females, aged(12.0±3.4)years, and nocturnal enuresis number per week is 2.3±1.0. The incidences of nocturnal polyuria and the reduction in maximum bladder capacity in the PMNE group was 34.9% and 11.6%, respectively. The incidence and frequency of detrusor overactivity (DO) in the severe PMNE group were significantly higher than those in the non-severe PMNE group [78.3% vs 45.0%, (5.5±1.8) times/h vs (3.4±1.0) times/h, respectively, all P<0.05]. It was found by the PSG that the severe PMNE group had significantly higher cortical arousal index, apnea hypopnea index (AHI), and percentage of N1+N2 phase in total sleep time, compared with the control group[(58.6±9.8)% vs (49.3±9.5)%, (9.4±4.4) times/h vs (3.1±1.5) times/h, (2.7±0.9) times/h vs (0.9±0.7) times/h] (all P<0.05). While the sleep efficiency of the severe PMNE group was substantially lower than that of the non-severe PMNE group [(86.4±4.3)% vs (91.0±3.9)%], the cortical arousal index and AHI were significantly greater than those of the non-severe PMNE group[(9.4±4.4) times/h vs (5.7±3.2) times/h, (2.7±0.9) times/h vs (1.9±0.7) times/h] (all P<0.05). In the PMNE group, there were positive correlations between cortical arousal index and nocturnal DO frequency or AHI (r=0.705, 0.765, P=0.001). Conclusions: Children with PMNE have nocturnal bladder dysfunction and abnormal sleep pattern, and there is a certain correlation between them. PSG and AUM are necessary for the evaluation and treatment of children with PMNE.