Discrimination Predicts Suboptimal Adherence to CPAP Treatment and Mediates Black-White Differences in Use

Abstract

Background: Although racial and ethnic differences in CPAP adherence for OSA are widely established, no studies have examined the influence of perceived racial discrimination on CPAP usage, to our knowledge. Research Question: (1) Do Black adults with OSA report experiencing greater amounts of discrimination than non-Hispanic White adults? (2) Is discrimination associated with poorer CPAP adherence over time, independent of self-identified race? (3) Does discrimination mediate the relationship between self-identified Black race and CPAP usage? Study Design and Methods: In this prospective study, Black and non-Hispanic White adults with OSA initiating CPAP were enrolled from two sleep centers and completed questionnaires including sociodemographics, perceived discrimination, daytime sleepiness, insomnia symptoms, and depressive symptoms. Perceived discrimination was measured using the Everyday Discrimination Scale (EDS). Black and White group comparisons for baseline sociodemographic variables, sleep symptoms, and perceived discrimination were performed with Student t test or χ2/Fisher exact test, as appropriate. A linear regression model was completed with self-identified Black race and EDS total score as the primary independent variables of interest and mean daily CPAP usage at 30 and 90 days serving as the dependent outcomes. This regression modeling was repeated after adjusting for psychosocial variables known to be associated with CPAP usage. EDS total score was explored as a potential mediator of the association between self-identified Black race and mean daily CPAP adherence at 30 and 90 days. Results: The sample for this analysis consisted of 78 participants (31% female, 38% Black) with a mean age of 57 ± 14 years. Sixty percent of the Black adults reported they experienced racial discrimination at least a few times each year. Relative to White adults, Black adults were also more likely to indicate more than one reason for discrimination (27% vs 4%, P =.003). Adjusting for discrimination, self-identified Black race was associated with 1.4 (95% CI, −2.3 to −0.4 h; P =.006) and 1.6 (95% CI, −2.6 to −0.6 h; P =.003) fewer hours of mean daily CPAP usage at 30 and 90 days, respectively. In the fully adjusted model, a 1-unit change in the total discrimination score (more discrimination) was associated with a 0.08-h (95% CI, 0.01-0.15 h; P =.029) and 0.08-h (95% CI, 0.01-0.16 h; P =.045) change in mean daily CPAP usage at 30 and 90 days, respectively. Interpretation: Adults with OSA who encountered racial discrimination experienced greater decrement in CPAP usage than those who did not experience racial discrimination.