Relationship Between Sleep Quality and Constipation Severity in Patients With Parkinson Disease: A Cross-sectional Study

BACKGROUND: Constipation in patients with Parkinson disease (PD) adversely affects motor symptoms, making defecation management critical. Sleep disturbance is another common complaint in patients with PD (PWP). Associations between sleep disturbances and constipation have been reported in recent studies on PD. If improving sleep quality is useful for managing constipation in PWP, it might serve as a new method of constipation management that is less physically and mentally distressing than laxatives. This study aimed to examine the relationship between sleep quality and constipation severity in PWP. METHODS: We administered a questionnaire on sleep and constipation to 1048 PWP. Constipation severity was assessed using Constipation Assessment Scale Japanese version 2 (CAS). General sleep quality was estimated using the Japanese versions of the Pittsburgh Sleep Quality Index (PSQI) and Athens Insomnia Scale. Sleep quality due to PD-specific nighttime problems was estimated using the Parkinson's Disease Sleep Scale-2 Japanese version (PDSS-2). We conducted a multiple regression analysis using the forced entry method to identify the variables that influenced CAS. RESULTS: We analyzed 350 PWP. Overall, 94.9% of PWP had constipation symptoms. The percentages of PWP with poor sleep were as follows: PSQI, 74.7%; Athens Insomnia Scale, 69.8%; and PDSS-2, 73.8%. Furthermore, 17.6% of the patients with constipation and 35.3% with sleep problems did not consult a healthcare provider. Multivariate analysis revealed that CAS was significantly associated only with PDSS-2 (standardized partial regression coefficient, 0.217; 95% confidence interval, 0.030-0.111). CONCLUSION: Poor sleep quality, related to PD-specific nighttime problems, was found be associated with worsening constipation severity. Nursing activities that help PWP with PD-specific nighttime problems have a more comfortable night's sleep would be key to alleviating constipation severity.