Wake-up stroke and sleep-disordered breathing: a meta-analysis of current studies

Sleep-disordered breathing (SDB) is a frequent comorbidity in patients with wake-up stroke (WUS). It affects the occurrence of this disease through its interference of breathing changes and sleep quality. We aim to assess the performances of sleep-disordered breathing in WUS. A systematical search for the studies that investigated sleep-disordered breathing in WUS was done in PubMed, Web of Science, and Cochrane Library. Data were extracted by two independent investigators, and then analyzed using the Revman 5.0 software. A total of five studies with 591 patients were included in the meta-analysis. The pooling data of sleep parameters showed that patients with WUS had a higher AHI and ODI than those with non-WUS (NWUS) [AHI: SMD: 0.58 (0.05, 1.10), P = 0.03; ODI: SMD: 0.63 (0.06, 1.21), P = 0.03). In addition, an increased incidence of severe SAS is found in WUS (OR: 3.18; 95% CI 1.27, 7.93; P = 0.01). However, no differences were found in AI, ESS, and the number of sleep apnea syndrome (SAS) between the two groups (P > 0.05). Therefore, WUS patients intended to have a severe SDB status, affecting the respiratory effects. Early prevention and attention should be paid on potential stroke sufferers with SAS, especially those with severe SAS.