Sleep Apnea and Incident Stroke in a National Cohort of Black and White Adults

Racial/ethnic differences have been documented in the relationship between obstructive sleep apnea (OSA) and stroke incidence, yet racial differences in OSA symptoms or treatment and their relationship with stroke incidence are underexplored and may contribute to stroke disparities. We comprehensively examined OSA symptoms and their relationships to stroke incidence by race/ethnicity. Data were collected from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, a population-based cohort of Black and White individuals in the United States. Participants free from a stroke diagnosis at baseline were included. Participants self-reported the following: (1) snoring; (2) daytime sleepiness; (3) provider-diagnosed sleep apnea (PDSA); and (4) treatment for PDSA using positive airway pressure (PAP). OSA risk was categorized as high or low based on the Berlin Sleep Questionnaire. Incident stroke was defined as first occurrence of stroke over an average of 12 (SD 3.9) years of follow-up. We report the relationships between snoring, OSA risk, PDSA, PAP therapy use, and incident stroke by race/ethnicity using Cox proportional hazards models after adjusting for demographic and socioeconomic factors and stroke risk factors. Among the 22,192 participants (mean age [SD] 64.2[9.1] years), 38.1% identified as Black. Overall, snoring was not associated with incident stroke (hazard ratio [HR] 0.98, 95% CI 0.85-1.13). However, among White individuals but not Black individuals, high OSA risk and PDSA were associated with incident stroke (HR 1.22, 95% CI 1.01-1.47; HR 1.33, 95% CI 1.04-1.70, respectively). PAP therapy use among those with PDSA (compared with non-PDSA) was associated with incident stroke in White individuals (HR 1.38, 95% CI 1.05-1.80). PAP therapy use among those with PDSA (compared with those with PDSA without PAP therapy use) was associated with reduced risk of incident stroke in Black (HR 0.39, 95% CI 0.17-0.91) but not White (HR 0.63, 95% CI 0.37-1.10) individuals. White individuals with high OSA risk and those with PDSA with or without PAP therapy use were at increased incident stroke risk, whereas Black individuals reporting PDSA and PAP had reduced incident stroke risk relative to those not using PAP. Future research is needed to understand the mechanisms underlying racial differences in OSA and stroke such as differences in assessment modes and treatment.