The Need for Social and Environmental Determinants of Health Research to Understand and Intervene upon Racial/Ethnic Disparities in Obstructive Sleep Apnea

Abstract

Obstructive sleep apnea (OSA), a sleep disordered breathing (SDB) disorder, affects at least 25 million adults in the United States and is associated with increased risk for hypertension, diabetes and cardiovascular disease. Racial/ethnic minorities have a disproportionate burden of OSA along with the health sequelae associated with this condition. Despite supporting evidence of racial/ethnic disparities, few studies have investigated SDB including OSA among minoritized racial/ethnic groups. In this scoping review of the literature, the authors summarize current findings related to racial/ethnic disparities in OSA, identified social and environmental determinants of health, treatment inequities, and promising evidence-based interventions and conclude with future research directions. Based on the scientific literature, minoritized groups had not only a high prevalence of OSA, which is largely undiagnosed and untreated, but also more severe OSA. Treatment adherence was also lower among minoritized racial/ethnic groups. Researchers have documented social determinants as drivers (e.g., neighborhood environment) of the disproportionate OSA burden among racial/ethnic minority children and adults. Lastly, there is evidence that culturally-tailored evidence-based interventions for OSA improve awareness, screening, and treatment adherence of OSA among racial/ethnic minorities; thus, providers and researchers should consider implementation of these social determinant of health informed interventions to reduce the burden of OSA.

Introduction

Sleep disorders and sleep health inequities are a public health burden. Obstructive sleep apnea (OSA), a sleep disordered breathing (SDB) disorder, is highly prevalent^{1, 2} and has been implicated as an emerging risk factor for hypertension, type 2 diabetes, cardiovascular disease, and mortality.^3–7 Cardiovascular disease related outcomes and early mortality are disproportionately prevalent among minoritized racial/ethnic groups.^{8, 9} Emerging evidence suggests that sleep disorders and adverse sleep health contribute to cardiovascular and overall health disparities.^10–13 Thus, addressing the burden of sleep disorders, particularly obstructive sleep apnea will likely aide in the reduction of sleep and health disparities. As a result of the urgent need to address racial/ethnic disparities in OSA, herein, we (a) reviewed and summarized the literature disclosing the current state of scientific knowledge on racial/ethnic disparities in OSA, (b) discussed the social determinants investigated, (c) reviewed treatments with demonstrated effectiveness, (d) discussed promising evidence-based interventions, and (e) concluded with future research directions in hopes of informing the development and rigorous testing of interventions designed to attenuate or eliminate disparities.

Literature Review Strategy

Focused on racial/ethnic disparities in SDB (especially OSA), we define “race” as a social construct with biological consequences that result from social, economic, and environmental determinants that are differentially experienced across racial/ethnic groups as a result of historical racist and discriminatory practices, laws, and policies on the basis of race/ethnicity.¹⁴ As defined by the National Institute on Minority Health and Health Disparities, a health disparity is “a health difference, on the basis of one or more health outcomes that adversely affects disadvantaged populations.¹⁵ Further, disparities are defined as inequities between racial groups that are preventable and unfair/unjust,¹⁶ and are related to any differences that are not due to clinical need or preferences for health care services.¹⁷ Relatedly, social determinants are considered the broad range of economic, social, neighborhood, and environmental factors as well as policies that influence access to opportunities and resources that can in turn directly or indirectly shape health.¹⁸

To review the literature on OSA disparities, we searched PubMed, Medline (Ovid), EMBASE, Google Scholar, and The Cochrane Library May-June 2021. The following search terms were used to identify English-language articles published in peer-reviewed journals without study design restrictions: ‘obstructive sleep apnea’/exp, ‘sleep apnea syndromes’/exp, ‘sleep disordered breathing’/exp, disparit*, health disparit*, ‘social determinants of health’, continental population groups, ‘population group’/exp, ethnic groups, (race* or racial* or minorit* or cultur*):ti,ab, ethnic*:ti,ab, black*:ti,ab, ((african or asian or mexican) adj american*):ti,ab, (Hispanic* or latin* or spanish).ti,ab, (white* or Caucasian* or European*):ti,ab, Asian*:ti,ab, Native*:ti,ab, Aborig*:ti,ab, Indian*:ti,ab, Pacific:ti,ab, Subcontinent:ti,ab, Chicano:ti,ab, Amish:ti,ab, arab*:ti,ab, Inuit*:ti,ab, jew*:ti,ab, Indigenous:ti,ab, colo?r*ti:ab, ‘socioeconomics’/exp, ‘socioeconomic factors’/exp, working poor, poverty, vulnerable populations, (socioeconomic* or poverty or poor or ses or social class* or employ* or unemploy* or income or education* or underserve* or vulnerable*):ti,ab, and (sex* or bisex* or homosex* or heterosex* or lesbian* or transgender* or lgbt). The search was limited to studies conducted in the United States (US); however, when deemed appropriate and useful, examples were drawn from research outside the US. While no restrictions were placed on the date of publication, the majority of articles were published starting in the early 2000s. Based on the aforementioned criteria, this search yielded 82 published articles, and below we summarize the literature on OSA or SDB among minoritized racial/ethnic groups including African American, Asian, Hispanic/Latinx, and American Indian (or Native American) children as well as adults.

Racial/Ethnic Disparities in Sleep Disordered Breathing including Obstructive Sleep Apnea

OSA is prevalent among minoritized racial/ethnic children and adults (Table 1) with the prevalence ranging from 5% to 86%.^{19, 20} Compared to non-Hispanic White adults, African American or Black adults have a higher prevalence of sleep apnea syndrome [apnea-hypopnea index (AHI) ≥ 5 plus sleepiness], daytime sleepiness, snoring and more severe sleep apnea.^{19, 21–24} Among a clinical sample, African American men had a higher apnea-hypopnea index, an objective measure of OSA, than White men of the same age while accounting for body mass index (BMI).²⁵ Similar findings are shown among elderly samples.²² In addition to the high prevalence of OSA, there was also a high burden of undiagnosed OSA. Data from a US-based cohort study found that only 16.2% of African-Americans who had polysomnography-defined moderate or severe sleep apnea reported a physician-diagnosis.¹⁹ This is supported by research among the largest longitudinal cardiovascular cohort study, the Jackson Heart Study. Johnson and colleagues reported that among 852 African-Americans in Jackson, MS, 24% had moderate or severe sleep apnea with 95% being undiagnosed.²⁶ These results underscore the need for screening in this population.

Table 1.

Studies Reporting on Racial/Ethnic Disparities in Obstructive Sleep Apnea (OSA) (N=24)

Study	Sample	Diagnostic Assessment	Obstructive Sleep Apnea Definition	Main Findings
Geovanini et al. (2018)4	390 African American 13 Chinese 430 Hispanic 511 White adults (mean age=68), Male (47%), Female (53%)	In-lab PSG	no OSA (AHI<5), mild (AHI = 5–14), moderate (AHI = 15–29), and severe (AHI ≥ 30).	30% African American, 4% Chinese, 35% Hispanic and 31% White adults, had moderate OSA. 27% African American, 0.5% Chinese, 42% Hispanic and 30.5% White adults had severe OSA.
Johnson et al. (2018)	664 Black (mean age=64.9) Male (30.9%) Female (69.1%) Jackson, MS residents	In home sleep apnea test (Type 3 sleep apnea device)	Moderate or severe OSA defined as REI ≥ 15	26% prevalence of moderate to severe sleep apnea
Chen et al. (2015)19	612 Black (mean age=68.8), Male (44.4%) Female (55.6%)) 262 Chinese (mean age=67.7), Male (49.6%), Female (50.4%)) 528 Hispanic (mean age=68.6), Male (47%), Female (53%) 828 White adults (mean age=68.8), Male (46.1%), Female (53.9%)	In lab PSG & self-reported doctor diagnosed sleep apnea, Sleep Questionnaire Survey	AHI>5 and categorized as mild (AHI = 5–14), moderate (AHI = 15–29), and severe (AHI ≥ 30)	17.9% White, 17.5% Black, 20.5% Hispanic, and 21.6% Chinese participants had moderate SDB. 12.4% White, 14.9% Black, 17.7% Hispanic, and 17.8% Chinese had severe SDB. 9.0% of participants reported doctor diagnosed sleep apnea.
Jean-Louis et al. (2008)20	421 Black adults Adherent (mean age=51) Male (43%) Female (57%) Non-adherent (mean age=52) Male (38%) Female (62%)	In lab PSG	AHI ≥5	91% of patients received a sleep apnea diagnosis and treatment.
Redline et al. (1997)21	253 African American Control Family (mean age=32.6) Male (38%) Female (62%) Index Family (mean age=34.8%) Male (53%) Female (47%) 622 White Control Family (mean age=31.7), Male (47%) Female (53%), Index Family (mean age=32.6%) Male (49%) Female (51%)	In home sleep monitor	RDI> 5, 10 and 15, for subjects < 25 yr, 26 to 55 yr, and > 55 yr, respectively	Sleep disordered breathing was twice as prevalent among African Americans than in Whites.
Ancoli-Israel et al. (1995)22	54 African American adults (mean age=70.8) Male (43%) Female (57%) 352 White adults (mean age=72.8) Male (47%) Female (53%)	In home sleep monitor	RDI>5	17% of African Americans and 8% of Whites had severe SDB.
Scharf et al. (2004)23	128 African American mean age=44.9), Male (50%), Female (50%) 102 White adults (mean age=49.2) Male (57.8%) Female (42.1%)	In lab PSG	RDI>5	53.9% of African Americans and 48% of White adults had more severe sleep apnea.
O’Connor et al. (2003)24	643 American Indian Male (43%) Female (57%) 90 Asian-Pacific Islander Male (51%) Female (49%) 648 Black Male (41%) Female (59%) 296 Hispanic Male (42%) Female (58%) 11,517 non-Hispanic white adults Male (46%) Female (54%)	The Sleep Habits Questionnaire & In lab PSG	Frequent snoring defined as snoring 3 to 5 nights a week or more Breathing pauses defined as cessation of breathing during sleep SDB defined as AHI ≥15	Persistent snoring was more common among Black (21%), Hispanic (29%) women and Hispanic (52%) men, compared to non-Hispanic White adults (39% male 19% female,) Breathing pauses was more common among American Indians (23% male, 10% female)
Pranathiag eswaran et al. (2013)25	340 African American Male (45%) Female (55%) 132 White adults Male (70%) Female (30%)	In lab PSG	AHI>5	The median AHI was 32.7 for African American patients and 22.4 for White patients.
Johnson et al. (2018)26	852 African American (mean age=63.1), Male (34%) Female (66%) Jackson, MS residents	In home sleep apnea test (Type 3 sleep apnea device)	AHI ≥15	23.6% prevalence of moderate-to-severe OSA
Goldstein et al. (2011)27	155 Black/African American 41 Hispanic 133 White 17 Other children Male (48.5%) Female (51.5%)	Questionnaire-PSQ, Sleep Related Breathing Disorders Scale	SDB defined as Mean PSQ Score> 0.33	SDB was found in 11.6% of Black children, 9.8% of Hispanic children, and 6.8% of white children.
Rosen et al. (2001)28	Term Children 166 Black, 268 White, 22 Other (mean age=9.6) Male (51%) Female (49%) Preterm Children 144 Black, 233 White, 17 Other (mean age=9.3) Male (51%) Female (49%)	In home monitor	SDB defined as (1) AHI≥5 event/h (2) Obstructive apneas ≥ 1 event/h, regardless of desaturation (3) Combination of criteria (1) & (2)	SDB was found in 4.8%, 8.1%, and 8.7% of Black children, and 1.0%, 1.4%, and 2.2% of White children, detailed by the apnea hypopnea index, the obstructive apnea index, and the combined definition, respectively.
Stepanski et al. (1999)29	68% African American, 19% Latino, 12% White, 1% Arabic children (mean age=5.9) Male (52%) Female (48%)	Clinical, PSG and audiovisual data	SDB defined as (1) frequent (≥5/h) episodes of upper airway obstruction (2) oxygen desaturation (< 90%), sleep fragmentation, or cardiac arrhythmia in association with episodes of upper airway obstruction	65% of African American, 62% Latino, and 68% of White children were diagnosed with SDB.
Seixas et al. (2016)31	1035 Black/African American adults (mean age=62) Male (31%) Female (69%)	Questionnaire-Apnea Risk Evaluation System	OSA defined as Apnea Risk Evaluation score ≥6	77% prevalence of moderate to high risk of OSA
Thomas et al. (2020)32	206 African American adults (mean age=55.6) Male (33%) Female (67%))	In home sleep apnea test (Type 3 sleep apnea device)	REI4% ≥ 15 events/hour	26.2% had moderate to severe sleep apnea
Yano et al. (2020)33	789 Black adults mean age=63) Male (26%) Female (74%))	In home sleep apnea test (Type 3 sleep apnea device)	SDB defined as (1) continuous variables (REI4P, REI3P, Sat<90, MinSaO2) in the primary analysis (2) a categorical variable in secondary analyses, where REI<5, REI ≥5 and <15, REI ≥15 and <30, and REI ≥ 30 is unaffected OSA, mild OSA, moderate OSA, severe OSA, respectively	14.7% prevalence of moderate OSA and 8.9% of severe OSA.
Leong et al. (2013)34	40 South Asian adults (mean age=43.8) Male (40%) Female (60%) 268 White European adults (mean age=46.6) Male (27.6%) Female (72.4%)	In home monitor	OSA defined as AHI ≥ 5 events/hour	85% of South Asian and 66% of White adults had OSA.
Ong et al. (1998)35	105 Asian adults (mean age=41.5) Male (87.6%) Female (12.4%) 99 White adults (mean age=41.2) Male (87.9%) Female (12.1%)	The Sleep Questionnaire and Assessment of Wakefulness & In lab PSG	Severe OSA defined as (1) RDI≥50 (2) SaO2≤69%	25% of Asians and 11.1% of White patients had severe OSA (RDI≥50). 20.6% of Asians and 4.2% of White patients had severe OSA (SaO2≤69%).
Genta et al. (2008)36	54 Japanese adults (mean age =53.3) 466 White adults (mean age=50.6)	In lab PSG	OSA defined as AHI ≥5 events/h	The proportion of individuals with OSA was 89% for Japanese descendants and 88% White patients
Lee et al. (2010)37	76 Chinese adults mean age=49.5) Male (82.9%) Female (18.1%)) 74 White adults (mean age=48.5) Male (79.7%) Female (21.3%)	In lab PSG	OSA defined as AHI ≥5 events/h	The severity of OSA was (35.3 ± 26.1 events/hr) for Chinese patients and (25.2 ± 16.3 events/hr) for White patients.
Shafazand et al. (2012)38	99 Cuban, 63 Puerto Rican, 4 Mexican, 9 Caribbean, 35 Central American, 49 South American, 23 Other adults (mean age=54) ale (62%) Female (38%)	STOP Bang Questionnaire & In lab video PSG	SDB defined as AHI ≥5 events/h	63% of participants had moderate to severe SDB (AHI ≥ 15).
Yamagishi et al. (2010)39	211 Hispanic adults (mean age=61.6) Male (48%) Females (52%)) 978 Japanese adults (mean age=63) Male (46%) Female (54%) 246 White adults mean age=62) Male (44%) Female (56%)	In lab (single-channel airflow monitor)	SDB defined as RDI ≥15 events/h	36.5% of Hispanic, 33.3% White and 18.4% Japanese participants had SDB.
Redline et al. (2014)40	Dominican 448 Male (mean age=38.9) 840 Female (mean age=39.6) Central American 588 Male (mean age=38.2) 905 Female (mean age=41.4) Cuban 897 Male (mean age=45.7) 1,011 Female (mean age=47.1) Mexican 2,297 Male (mean age=38.0) 3,807 Female (mean age=39.4) Puerto Rican 943 Male (mean age=42.0) 1,348 Female (mean age=44.9) South American 390 Male (mean age=40.2) 550 Female (mean age=44.5) Mixed or Other adults 184 Male (mean age=34.4) 232 Female (mean age=35.3)	In home sleep apnea monitor - Apnea Risk Evaluation System	SDB severity defined as minimal (AHI ≥5), moderate (AHI ≥15), and sever (AHI ≥30)	9.8% of participants had moderate or severe SDB
Alshehri et al. (2020)41	3779 Hispanic/Latino adults (mean age=55.32) Male (42.1%) Female (57.9%)	In home sleep monitor - Apnea Risk Evaluation System	Continuous AHI with 3% of desaturation	Mean AHI: 8.46 ± 13.4

Note: The articles are listed in the order presented in the manuscript.

A similar OSA burden for adults is also observed among African American pediatric populations. A study of young children found that snoring, a symptom of OSA, but not sleep-disordered breathing was more common among Black children compared to their White counterparts.²⁷ However, other studies have reported a SDB disparity. In a study of 8 to 11-year-old children, African-American children were more likely to have SDB compared to White children.²⁸ The authors of the prior study reported preterm status as a significant risk factor for increased SDB risk in African American children. Future studies should explore preterm status as a contributor to SDB. Interestingly, a study of African American, Hispanic/Latinx, White, and Arabic children and adolescents referred for sleep center evaluation found a similar severity of SDB by race/ethnicity, but yet, found more frequent and more severe oxygen desaturation by pulse oximetry in African American children.²⁹ The study findings suggested African American children may be at increased risk for cardiovascular consequences of SDB.

The high prevalence of obstructive sleep apnea is particularly problematic among African Americans, given the higher burden of cardiovascular disease (CVD) risk factors that emerge earlier in life.³ For instance, a recent study found childhood OSA persisted to adolescence and that it was associated with hypertension in adolescence.³⁰ Studies within African Americans have shown that OSA is associated with resistant hypertension,⁵ uncontrolled blood pressure,³¹ nighttime blood pressure,³² and higher blood glucose levels³³. Furthermore, in diverse samples, researchers have found that the association between sleep apnea and CVD is stronger among African Americans.⁴ OSA is likely a target to reduce CVD among African Americans.

Similar to African Americans, Asian populations have a particularly high prevalence of OSA. Although sleep data among Asian Pacific Islander-identified ethnic groups are scant, data outside the US suggest Asian ethnicity is associated with OSA. For instance, a study in England found South Asian adults had a higher prevalence and greater severity of OSA than White European study participants.³⁴ In fact, among a clinical adult sample of Asian and White patients in the US, Asian patients had more severe polysomnography-measured OSA, but no observed differences in severity of questionnaire-based symptoms.³⁵ Asian adults may also under-report symptoms, which should be further explored. Furthermore, data from the Multi-Ethnic Study of Atherosclerosis demonstrated that Chinese Americans had higher odds of objectively-measured SDB, with differences most evident after adjusting for BMI.¹⁹ In the prior study, Chinese individuals had the lowest prevalence of doctor-diagnosed obstructive sleep apnea,¹⁹ which may be attributable to social factors or structural barriers that adversely impact access to care leading to underdiagnoses while underscoring the need for screening. Similar findings exist among Japanese descendants. In a study of White and Japanese men in São Paulo Brazil, the authors reported that the risk of OSA associated with obesity is likely largely under-recognized among Japanese descendants.³⁶ This finding suggests there may be a delay or under-diagnosis of OSA among obese Japanese descendants. While acknowledging that some of the OSA burden among Asian populations may be attributable to variations in craniofacial anatomy,³⁷ strategies are needed to screen and treat Asian subgroups with unrecognized, underdiagnosed OSA potentially due to social determinants of health.

Hispanic/Latinx populations are also disproportionately burdened by OSA. In a study among a clinical cohort of US Hispanic/Latinx adults in South Florida, 63% of the participants who underwent polysomnography had moderate-to-severe OSA.³⁸ In a cross-cultural study of Hispanics/Latinx, White Americans, and Japanese adults in Japan, Hispanic/Latinx adults had a higher prevalence of SDB than White and Japanese participants.³⁹ However, BMI explained the differences. When examining OSA among pediatric samples, a study of young children found that snoring was more common among Hispanic/Latinx than non-Hispanic/Latinx White children.²⁷ Similarly, in an adult population, snoring was also more common for Hispanic/Latina women, even after adjustment for BMI.²⁴ Targeting snoring among this population may reduce OSA burden.

Given the heterogeneity of the Hispanic/Latinx population, conducting within-group analyses is critically important. In the Hispanic Community Health Study/Study of Latinos, SDB was assessed among Hispanic/Latino individuals of diverse backgrounds. Redline et al. found that 25.8% of the study population met minimal criteria for SDB (AHI ≥ 5).⁴⁰ Although not statistically significant, the age-adjusted prevalence of moderate or severe SDB was highest among Puerto Rican women and lowest among South American women.⁴⁰ Among men, the prevalence of SDB was highest among Cuban and “mixed/other” men and least prevalent among Puerto Rican and South American men.⁴⁰ Consistent with data among African Americans, SDB is associated with an increased prevalence of diabetes and hypertension among Hispanic/Latinx populations,^{40, 41} and the associations vary by Hispanic/Latino group. Thus, underscoring the importance of conducting within-group studies, and OSA as a target to reduce the CVD burden among Hispanic/Latinx populations.

Overall, American Indian (or Native American) populations are underrepresented in sleep research. In one study with a racially/ethnically diverse sample, which included 5% American Indian adults, breathing pauses were more common among American Indians in comparison to non-Hispanic White adults.²⁴ The prior result suggests that there may be a disproportionate burden of OSA among American Indian populations, but more research is needed.

Social Determinants of Obstructive Sleep Apnea

The social determinants of OSA disparities are poorly understood. Limited literature shows that neighborhood environment is a contributor to OSA and OSA disparities.^42–46 Although determinants are likely multi-factorial, the most commonly studied social determinant of health is of the neighborhood environment and most of the literature on neighborhood environment and obstructive sleep apnea has been conducted among pediatric populations. These studies have shown that living in a socioeconomically disadvantaged neighborhood increases the risk of OSA.^{44, 46} For instance, among a sample of children in Canada, Brouillette et al. reported that the highest probability of OSA prevalence was observed among children referred from the most disadvantaged census tracts.⁴⁶ A study among children in Canada found that children with OSA were more likely to reside in disadvantaged neighborhoods.⁴⁶ Neighborhood disadvantage likely contributes to OSA risk disparities since neighborhood environments are shaped by racial residential segregation from health-promoting resources, socioeconomic status (SES), and immigration status.⁴⁷ As a result of historical discriminatory housing practices and environmental racism, minoritized racial/ethnic groups are more likely to live in lower SES neighborhoods and are exposed to more environmental hazards.⁴⁸ For example, ambient air pollution is associated with disturbed sleep and OSA.^49–56 Air pollution can negatively affect the nervous system, and can cause oxidative stress or inflammatory damage, which contributes to disturbed sleep.⁵⁷ In addition to air pollution, socially disadvantaged neighborhoods tend to have less access to high-quality medical care, sleep physicians, and behavioral sleep medicine providers.⁵⁸ Taken together, this evidence supports that neighborhood environment is associated with OSA.

A growing literature has shown that neighborhood environment partially explains racial/ethnic disparities in OSA. In two studies among adolescents, the authors found that 50–55% of the racial/ethnic disparities in OSA was attributable to neighborhood environment.^{44, 45} More specifically, neighborhood poverty explained the racial disparity in pediatric OSA syndrome.⁴⁵ Neighborhood poverty may act as a proxy for adverse environmental exposures that increase OSA risk. In a separate study, residence in a disadvantaged neighborhood and African-American race predicted OSA in middle childhood. ⁵⁹ Similar data among adults are lacking. OSA is often undiagnosed in minoritized populations, thus disturbed sleep, measured as wakefulness after sleep onset (WASO), may serve as proxy or symptom. In a sample of adults, neighborhood disadvantage explained 24% of the racial disparity in WASO.⁶⁰ A.^{61, 62} The health disparities literature has shown that racial/ethnic minoritie Although neighborhood disadvantage, often a measure of SES, is associated with OSA, most studies have reported a null finding between individual-level SES and OSs are more likely to live in environments below their individual SES level,^{63, 64} which may explain the prior result.

In addition to neighborhood environment, individual-level factors such as exposure to secondhand smoke can increase the risk of OSA. In a study of African American, White and additional races (not specified in the article), children with exposure to secondhand smoke had more severe OSA, and this was more common among non-Hispanic White children.⁶⁵ Aside from secondhand smoke, asthma and obesity are known individual-level risk factors of OSA. Among a diverse sample of urban adolescents, moderate persistent asthma was associated with higher odds of symptoms.⁶⁶ However, a study among Black, Hispanic/Latinx and White adolescents found that asthma reduced the likelihood of severe OSA by approximately 14% among obese patients and 8% among non-obese patients; and obesity was associated with severe OSA.⁶⁷ More research is needed to further understand the association between asthma and OSA and variation by obesity status and setting (urban vs. rural).

Adult and pediatric studies have reported the racial/ethnic differences in OSA may be explained by differences in BMI.^{24, 39, 67} Obesity is a known individual-level risk factor for OSA, and racial/ethnic minorities are more likely to be obese,⁶⁸ which is partially due to social and structural determinants of health. Racial/ethnic minorities are more likely to live in disadvantaged neighborhoods that often are food deserts (e.g., an area that lacks fresh good quality food). These areas are often limited in access to healthy foods – particularly fruits and vegetables, which can increase risk of obesity. Also, neighborhood crowding is more prevalent, which is associated with BMI and OSA.⁴² Racial/ethnic minorities are also exposed to more structural racism and to psychosocial stressors including interpersonal racism and discrimination, which are associated with obesity.⁶⁹

Psychosocial factors may also be individual-level determinants of OSA among racial/ethnic minorities. In a sample of African Americans with metabolic syndrome, Ceide et al. reported that anxiety and depression were associated with greater odds of OSA.⁶² This is consistent with an OSA screening tool developed by Johnson and colleagues that included depression in the model to predict OSA among African Americans.⁷⁰ Psychosocial factors may be salient individual-level risk factors for OSA among racial/ethnic minorities.

Racial/Ethnic Disparities in Treatment for OSA

The role of social determinants of health are important to consider in the treatment of OSA. Access to care and health insurance are contributing factors to disparities in treatment. Among a study of White, Black and additional races (not specified in the article) who attended either a voluntary hospital (VH) or a minority serving institution (MSI), 42% of the MSI patients with OSA failed to follow-up for treatment, compared to 7% of the VH group.⁷¹ The authors report a similar prevalence of OSA in the VH and MSI patient groups. In exploring the reasons for this difference, the MSI group had either public health insurance (Medicaid) or no health insurance, which limits the access to treatment outside of the institution. This result highlights access to care as a potential structural barrier to treatment of OSA.

Data regarding racial/ethnic differences in CPAP adherence is mixed though the majority of studies suggests lower acceptance by racial/ethnic minorities. A study among African American and White patients showed similar CPAP acceptance rates, defined as the mean number of self-reported hours per week of CPAP use.²³ The optimal levels of CPAP were the same by race, which suggests that the tendency for airway closure was similar, therefore, in theory the treatment should not be more difficult in one race compared to the other. However, data from a multi-center clinical trial showed that CPAP acceptance was lower in Black compared to non-Black participants, and the participants from the lowest SES zip codes were of Black race (59%).⁷² The prior study also demonstrated that CPAP acceptance was lower among those in the lowest quartile SES zip codes. Similar data exist among older adults with neurological disorders, which has shown that adherence to OSA treatment is less likely among Black and Hispanic/Latino older adults compared to their White counterparts.⁷³ A study conducted in an urban public hospital found that race was associated with CPAP nonadherence. In fact, African Americans were 5 times as likely to be nonadherent than White adults.⁷⁴ However, the sample size for White patients was small (6%). There is a need to understand the barriers to CPAP adherence among racial/ethnic minority groups, and if individualized combination therapies (e.g., CPAP and mandibular repositioning devices) based on needs could improve adherence and treatment effectiveness.

Health Equity Interventions Targeting OSA

Intervention approaches that leverage social determinants of health frameworks have been developed to address racial/ethnic disparities in OSA. One strategy to reduce sleep disparities is to improve OSA diagnosis and treatment among the populations most-at-risk. For example, Jean-Louis et al., conducted a randomized controlled trial using a culturally-tailored web-based application to improve OSA self-efficacy among community dwelling Black adults.^{75, 76} Participants were provided access to the Tailored Approach to Sleep Health Education (TASHE) intervention for 2 months and were assessed at three intervals. Participants exposed to the TASHE content described improved OSA self-efficacy at 2 months compared to individuals who received the sleep health education.⁷⁶ Similarly, a study by Jean-Louis et al. assessed the effectiveness of a telephone-delivered intervention to improve OSA evaluation and treatment among Blacks with metabolic syndrome.⁷⁷ To improve these outcomes, participants received culturally and linguistically tailored health messages from a health educator to assess their challenges and willingness to change behavior. The intervention was effective in increasing sleep consultations and evaluations.⁷⁷ These prior studies are an example that tailored approaches are beneficial intervention strategies for increasing OSA assessment. Additionally, peer-based approaches are also beneficial. In a population of African Americans, a peer-based sleep health education and social support approach was used to increase OSA assessment and treatment.⁷⁸ As part of the intervention, participants received 10 counseling sessions with a sleep health educator to encourage screening, diagnosis, and treatment adherence.⁷⁸ Preliminary findings showed that fewer African Americans in the control condition scheduled an OSA assessment appointment compared to those in the intervention.⁷⁸

Similar data among pediatric populations are lacking. However, among a pediatric study of 136 children, the importance of social determinants of health was underscored. There were longer intervals from baseline evaluation to PSG among children with public insurance. Thus, the authors concluded that PSG may be a deterrent for children with public health insurance or low SES.⁷⁹ This study provides a great example for the need to understand social determinants contributing to OSA disparities, particularly surrounding delay in care with PSG and surgery for children with sleep-disordered breathing. Additionally, since obesity is a strong risk factor for OSA, weight loss interventions also promoting family cohesion and emotional involvement has been shown to enhance weight loss among African Americans, and may prove important for addressing pediatric OSA.⁸⁰

Future Research Directions

In this review, we identified both contextual-level factors (including social determinants such as neighborhood environment) and individual-level clinical and psychosocial factors as potential contributors to racial/ethnic disparities in OSA risk, prevalence, and treatment over the life course. We also reviewed promising data from efficacy trials of social determinants of health informed interventions that targeted OSA screening and treatment in African American adults through the delivery of culturally- and linguistically-tailored sleep health education about OSA. While these represent important scientific advances in addressing racial/ethnic disparities in OSA prevalence and treatment, we identify three future research directions that represent key scientific opportunities in contemporary sleep medicine.

First, prevalence of OSA is high and appears to vary by race/ethnicity; therefore, we urge clinicians and researchers to consider the testing and implementation (if effective) of tailored risk-factor assessments across race/ethnicity groups in order to move more individuals to treatment. For example, Johnson et al. developed a screening tool for African Americans with better predictive properties than more commonly used screening tools.⁷⁰ Similarly, a sex-specific screening tool designed for Hispanic/Latinx populations was also more predictive.⁸¹ Both of these tools are available online.^{70, 81} Importantly, none of these tailored screening tools target pediatric OSA, which warrants future research.

Second, it is critical for the sleep medicine field to expand its focus from investigation of precision medicine that focuses on genetic factors in SDB to “precision public health.”⁸² While scientific evidence has demonstrated the heritability of multiple aspects of OSA⁸³ including differences in craniofacial structural features leading to differential susceptibility³⁷, non-genetic factors (e.g., food deserts or swamps in low-income communities) can contribute to differential group vulnerability through social disadvantage leading to, for instance, increased obesity risk. The precision public health approach will expand the field’s opportunity to intervene by supporting the identification of multi-level influences (not mainly genetic with limited intervention levers) on sleep-disordered breathing across the life course. These efforts can inform the development of, for example, multi-factorial community-level interventions that reflect multifactorial and modifiable determinants.⁸⁴ Moreover, since health insurance provisions alone will not address disparities caused by broader societal forces, there is a clear need for research comprehensively investigating the broad structural and individual-level social as well as environmental determinants of sleep health beyond the neighborhood. For instance, future research could determine the influence of under-resourced, obesogenic residential as well as occupational environments on OSA risk overall and in terms of racial/ethnic disparities in OSA. Noting the importance of employing proactive population-level efforts to change adverse social and physical environments that will likely reduce (vs. merely document) OSA risk, additional investigations could include (but are not limited to) the effects of structural racism that can lead to differential exposure to household income and wealth, air pollution, occupational hazards, insecurity in terms of housing, job, and food, access to sleep specialists in underserved areas, and health (including sleep) literacy influenced by differences in educational attainment. Adverse social and physical exposures could, for instance, increase obesity risk – a strong OSA risk factor. Relatedly, these efforts must be coupled with theory-informed research (e.g., intersectionality) that examines how multiple social identities (e.g., race, ethnicity, gender, sexual orientation) that reflect differential access to power, privilege, and marginalization intersect with these structural and individual-level exposures to shape OSA risk.⁸⁵ Additionally, it is critical to conduct more within racial/ethnic group studies to in order to identify the drivers of OSA within the population. Furthermore, socially vulnerable groups such as individuals who are minoritized and women need to be thoughtfully included in recent efforts to identify OSA phenotypes through clustering algorithms that can contribute to more personalized care or treatment.⁸⁶ In terms of symptom subtypes, it is important to know which phenotypes are associated with cardiovascular disease across diverse populations as current data.^87–89 This recommendation also applies to research focused on identifying potentially superior measures (e.g., hypoxic burden) to AHI.^90–92

Third, there is an urgent need to move beyond the mere documentation of racial/ethnic disparities in OSA prevalence and treatment to the rigorous development, testing, and (if effective) wide implementation and dissemination of health equity focused multi-level interventions for OSA across the life course. For example, Bonuck et al., designed a multi-level intervention for parent-child dyads in Head Start programs that involved individual-level sleep education, a sleep media campaign, a local sleep medicine specialist in the community and knowledge-translation strategies to change policy.⁹³ The prior study is currently in progress, to-date results have not been published. More studies that consider the nesting of individuals within environments with a variety of adverse and health-promoting exposures that are also culturally and linguistically tailored and that leverage the engagement of individuals along with their networks of social support are needed. Similarly, collaborative interventions that involve physicians, clinical settings, school, and community (including for example community health workers) may be the most advantageous for reducing burden of OSA among racial/ethnic minority pediatric and adult populations²⁷, though this research is in its infancy. Equally important will be the systematic evaluation of interventions and their implications for health equity in order to guard against potential unintended consequences such as the widening vs. narrowing of health disparities.⁹⁴ Further, interventions that target improvement of patient-provider communication as well as bolster patient satisfaction, self-efficacy, or build trust across racial/ethnic groups may represent promising and new avenues of research. To that end, a recent individual-level randomized controlled trial found that CPAP plus motivational enhancement, a behavioral intervention that targets ambivalence and self-efficacy, compared to CPAP alone increased CPAP adherence of 99 minutes in adults with moderate-to-severe OSA and cardiovascular morbidity.⁹⁵ Notably, over 85% of participants in this trial were non-Hispanic White, underscoring significant gaps in the testing of these evidence-based treatments that promote adherence in health disparity populations at risk of OSA and at greater risk of being undertreated for OSA. Similar data are needed among pediatric populations. There is a clear need to devote resources to conduct research and intervene earlier in the life course. Future intervention research should seek to further diversify the sample composition of sleep medicine clinical trials in order to increase the generalizability of study findings,^{95, 96} and apply rigorous theory-informed implementation science frameworks and methods,^{97, 98} as well as community-based participatory research principles and precision public health⁸⁴ to identify implementation strategies and community-generated solutions to address racial/ethnic disparities in OSA prevalence and treatment.

Key points.

• Obstructive sleep apnea is disproportionately prevalent and severe among racial/ethnic minority children and adults.

• Asian, especially Chinese and Japanese, Black and Hispanic/Latinx adults and children have a particularly high prevalence of undiagnosed and untreated obstructive sleep apnea.

• There is limited research among American Indian children and adults.

• The most commonly studied social determinant of health, neighborhood environment, partially explains racial/ethnic disparities in obstructive sleep apnea for adults and children.

• Culturally-tailored evidence-based interventions that leverage social determinants of health frameworks have been shown to reduce the burden of OSA among racial/ethnic minorities.