Evaluation of the relationship between brainstem lesions and apnea hypopnea index in patients with multiple sclerosis.

Background: Obstructive sleep apnea (OSA) may be more prevalent in people with multiple sclerosis (MS) and previous work suggests possible association with demyelinating brainstem lesions.

Objectives: The objectives of this study were to assess the relationship between demyelinating brainstem lesions in patients with MS referred for polysomnography (PSG) and the severity of the apnea-hypopnea index (AHI).

Methods: A total of 122 people with MS or clinically isolated syndrome (CIS) who underwent PSG due to concern for OSA or hypersomnia at two institutions between 2010 and 2022 were included. AHI was associated with the number of and presence of brainstem demyelinating lesions on magnetic resonance imaging (MRI) obtained within 1 year of PSG after controlling for body mass index (BMI), age, sleep study type, study center, and study year.

Results: Having one brainstem lesion was significantly associated with mildly elevated AHI (5 ⩽ AHI < 15; odds ratio (OR) = 2.71, 95% confidence interval (CI) = 1.29-5.67) and two or more lesions was associated with higher odds of mildly elevated AHI (OR = 3.27, 95% CI = 1.83-5.85) and moderately/severely elevated AHI (AHI > 15; OR = 3.23, 95% CI = 1.91-5.47). The presence of brainstem demyelinating lesion(s) conferred a higher odds of mildly elevated AHI (OR = 3.00, 95% CI = 1.75-5.16) and moderately/severely elevated AHI (OR = 1.65, 95% CI = 1.08-2.52).

Conclusions: These data suggest that brainstem lesions may be associated with elevated AHI in people with MS.