Sleep apnea and dysphagia in patients after a stroke recovering in convalescence rehabilitation

Abstract

Statement of problem

Sleep apnea is prevalent among patients after a stroke and can complicate recovery, particularly in those with dysphagia. While studies have investigated sleep apnea in patients after a stroke in acute-care settings, its prevalence and impact of those in convalescent rehabilitation remain largely unknown.

Purpose

The purpose of this clinical study was to investigate the prevalence and severity of sleep apnea among patients after a stroke in convalescent rehabilitation and to explore the relationship between the severity of sleep apnea and dysphagia.

Material and methods

In total, 196 patients after a stroke hospitalized in a rehabilitation hospital in Chiba Prefecture, Japan were enrolled in this study. The participants had suffered a stroke and had been admitted for post-stroke rehabilitation after being discharged from acute-care hospitals. An overnight sleep test was administered with WatchPAT, which measured the apnea–hypopnea index (AHI), minimum SpO₂ (MinSpO₂), and 3% oxygen desaturation index (ODI3%). Functional oral intake level was assessed with the Functional Oral Intake Scale (FOIS). Statistical analyses were conducted by using multiple regression followed by the 2-sample t test, Kruskal–Wallis tests, and the chi-squared test (α=.05).

Results

Among the initial 196 participants enrolled, 140 participants (78 men and 62 women; mean age, 73.3 ±12.4 years) underwent a sleep test, with only 91 completing it. Out of the 91 participants, 85 (93.4%) had sleep apnea, and the prevalence increased to 95.7% specifically among participants with dysphagia. Significant differences in Japan Coma Scale scores (P<.001) and modified Rankin Scale scores (P<.001) were observed between the tube-dependent (FOIS 1 to 3) and total oral diet (FOIS 4 to 7) groups. Multiple regression analysis revealed a significant association between AHI and BMI (P=.020), and AHI and FOIS (P=.007), adjusted for age, sex, and confounding factors.

Conclusions

This study revealed a high prevalence of sleep apnea among patients after a stroke in convalescent rehabilitation, as well as a significant correlation between the severity of sleep apnea and dysphagia. Clinicians should consider sleep apnea management as a critical component of post-stroke rehabilitation, given its potential for improving swallowing function.