Lack of Worsening of Sleep-Disordered Breathing After Recurrent Stroke in the BASIC Project.

STUDY OBJECTIVES: To investigate the difference in sleep-disordered breathing (SDB) prevalence and severity after an index and recurrent stroke.

METHODS: In a sample of 40 subjects, home sleep apnea tests were performed a median of 10 days after an index ischemic stroke and 14 days after a recurrent ischemic stroke. A respiratory event index (REI) of ≥ 10 events/h (apneas plus hypopneas per hour of recording) was used to define clinically significant SDB. The relative difference in REI or relative SDB prevalence was used to compare the post-recurrent stroke measurement with that made after the index stroke, and was expressed as a rate ratio (RR) or prevalence ratio (PR). Adjusted regression models (negative binomial for REI and log binomial for SDB) included change in body mass index and time between the events.

RESULTS: The median time from index to recurrent stroke was 330.5 days (interquartile range [IQR]: 103.5, 766.5). The median REI was 17.5 (IQR: 9.0, 32.0) after the index stroke and 18.0 (IQR: 11.0, 25.5) after the recurrent stroke. The within-subject median difference was zero (IQR: -9, 7.5). The relative difference in REI was not significant in unadjusted or adjusted (RR: 0.97 [95% confidence interval: 0.76, 1.24]) models. The prevalence of SDB was not different after the recurrent stroke compared with the index stroke, in unadjusted or adjusted (PR: 1.10 [95% confidence interval: 0.91, 1.32]) models.

CONCLUSIONS: In this within-subject, longitudinal study, neither severity nor prevalence of SDB worsened after recurrent stroke.