Lack of repercussions of sleep apnea syndrome on recovery and attention disorders at the subacute stage after stroke: A study of 45 patients

Introduction Sleep apnea syndrome (SAS) frequently occurs after a stroke. Its association with a poor prognosis is open to discussion. Objective To study, in a physical and rehabilitation medicine (PRM) unit, the possible repercussions of SAS on neurological and functional recovery as well as attentional abilities following a stroke. Patients and methods Forty-five patients, all of whom had recently had a stroke without previously documented SAS, were screened using the ApneaLink® system. An apnea-hypopnea index (AHI) score ≥10 was considered as indicative of SAS. The NIHSS, Fugl-Meyer (FM) and Functional Independence Measure (FIM) Scales were applied on admission and at two months as means of assessing neurological and functional recovery, which was expressed by the difference between the first and the second scores (delta FM, delta NIHSS, delta FIM). The Battery Attention William Lennox (BAWL) Test was given once in order to evaluate attention disorders. SAS severity was categorized according to the AHI. We compared the groups formed (mild, moderate and severe) using the same method. Results Twenty-eight patients (62.2%) presented AHI ≥ 10. Stroke characteristics were comparable in the SAS+ and the SAS– groups, with average post-stroke time lapse of 26 days, initial average FIM score of 71.2 points ± 26.3 and initial average NIHSS score of 8.9 ± 4.9. The demographic characteristics of the two groups were likewise comparable with the exception of age, as the SAS+ group was pronouncedly older (65.4 vs. 53.5 years). As for delta FIM, which evaluated functional recovery, it averaged 31.8 ± 20.6. Cases of SAS were found to be mild (37.1%), moderate (28.6%) or severe (34.3%). No significant difference was observed on admission or at 2 months as regards the clinical scales or the BAWL test between the two groups or according to severity, except for the NIHSS score at 2 months in the severe sub-group. Discussion and conclusion This study did not demonstrate the supposed repercussions of SAS on the recovery or attentional abilities of post-stroke patients. The tests were maybe given too early; they should take place at a lengthier time interval after the stroke, and also to be more complete.