Linking ethnic/racial discrimination to sleep in teens

Yip, Xie, Cham, & El-Sheikh (2022) published “Linking Ethnic/Racial Discrimination to Adolescent Mental Health: Sleep disturbances as an explanatory pathway” in Child Development. I’ve written before about sleep and it is a favorite topic, in part, because in copy-editing thousands of social histories I have been shocked by how often parents or teens report sleep disturbances. This is another long post. 

Yip et al. observe that “sleep is especially elusive for adolescents,” adding that, “A growing body of research finds that adolescent sleep is sensitive to daily social experiences, with stress having a particularly important influence (Campbell et al., 2020; Mellman et al., 2018; Rubens et al., 2018; Yap et al., 2020).” Their work is based on the race-based disparities in stress and sleep in context (RDSSC; Levy et al., 2016) model which proposes that sleep disturbances serve as an intermediary, biological pathway through which ethnic/racial discrimination stress ultimately leads to cascading effects on developmental outcomes. They cite extensive research linking poor sleep and compromised mental health outcomes (this article is available as full text). Sleep disturbance has been linked to key somatic and mental health indicators including:

• mood, fatigue, muscle pain, backache, and dizziness  

• depressive symptoms, anxiety, and psychological distress 

• decoupling of cortical and limbic regions of the brain reducing control 

• adverse impacts on alertness and neurobehavioral functioning 

Theirs is a longitudinal study of 350 of an ethno-racially diverse sample of 350 ethno-racially diverse ninth-grade adolescents (69% females) adolescents, 76 Black, 145 Asian (74% Chinese, 8% Korean, 4% Indian, 1% Filipinx, 1% Vietnamese, and 12% other), and 129 Latinx (25% Dominican, 24% South American, 22% Mexican, 15% Puerto Rican, 5% Central American, and 9% other), 72% of whom live in socioeconomically disadvantaged neighborhoods.

Adolescents’ daily ethnic/racial discrimination was measured using the six-item Racial/Ethnic Discrimination Index (“Today, I was treated unfairly because of my ethnicity/race,” “I felt stress because of my ethnicity/race,” “Others treated me poorly because of my ethnicity/race,” “I was teased because of my ethnicity/race,” “I felt uncomfortable because of my ethnicity/race,” and “I felt unsafe because of my ethnicity/race.”) published elsewhere (Feng et al., 2021). 

An adapted, daily measure of the Pittsburgh Sleep Quality Index (PSQI; Buysse et al., 1989 assessed adolescents’ previous-day nighttime disturbance (eight items, e.g., “woke up in the middle of the night or early morning”) and daytime dysfunction (two items, e.g., “had trouble staying awake while driving, eating meals, or engaging in social activity,” and “how much of a problem has it been for you to keep up enough enthusiasm to get things done”). The Stanford Sleepiness Scale (Stanford Sleepiness Scale, 2017) assessed adolescents’ previous-day daytime sleepiness. This single item scale was rated on a 7-point Likert scale, ranging from 0 (felt active, vital, alert, or wide awake) to 6 (felt asleep throughout the day), with higher scores reflecting more daytime sleepiness. 

Five indicators of adolescent mental health, both daily-and person-level, were included in the study: negative mood, anxious mood, positive mood, rumination, and somatic symptoms. An adapted version of the Profile of Mood States (McNair et al., 1971) assessed daily negative mood (4 items, i.e., sad, hopeless, discouraged, and blue), anxious mood (four items, i.e., anxious, nervous, unable to concentrate, on edge/uneasy), and positive mood (four items, i.e., happy, calm, joyful, and excited). Adolescents’ somatic symptoms were measured using the Index of Somatic Symptoms (Walker et al., 2001), a daily scale adapted from the Children's Somatization Inventory (Garber et al., 1991). Adolescents rated six types of symptoms (i.e., headache, nausea, tiredness, sore muscles, stomachache, and feeling weak) on a 4-point scale ranging from 0 (not at all) to 3 (a whole lot). Rumination (i.e., a passive coping with repeated thinking about the negative situations) was measured using an adapted version of the subscale of the Children's Response Styles Questionnaire (Abela et al., 2004), a 4-item daily measure (e.g., Why can't I handle things better?). 

They note that “reports of mental health that are collected at the daily level are conceptually different from retrospective reports of mental health; daily reports assess dynamic, day-to-day fluctuations of adolescents’ mental health, whereas retrospective reports (whether assessed at a single time, or repeated over time) capture a broader assessment of adolescents’ experiences over the past 2 weeks.”  Results include the following:

• daily ethnic/racial discrimination was associated with greater same-day sleep/wake problems (i.e., nighttime disturbance, daytime dysfunction, and daytime sleepiness) and more negative mental health outcomes (i.e., higher levels of negative mood, anxious mood, rumination, and somatic symptoms as well as lower levels of positive mood); 

• daily sleep/wake problems were associated with worse next-day mental health outcomes across days; 

• Across days, daily positive mood was negatively associated with all negative mental health outcomes; daily unfavorable mental health variables were positively correlated with each other;

• In addition, person-level nighttime disturbance (the average 14 days of nighttime disturbance) was associated with lower levels of positive mood at T2; 

• on days in which adolescents experienced ethnic/racial discrimination, they reported greater same-day nighttime disturbance; 

• on days in which adolescents had greater daily nighttime disturbance, they also reported more negative mood, anxious mood, rumination, and somatic symptoms the next day; 

• adolescents who reported more ethnic/racial discrimination in the past 6 months also reported greater daily nighttime disturbance; 

• daily nighttime disturbance partially or fully mediated the impact of daily ethnic/racial discrimination and ethnic/racial discrimination at T1 (i.e., discrimination in the preceding 6 months) on daily mental health outcomes, including negative mood, anxious mood, rumination, and somatic symptoms;

• on days in which adolescents experienced ethnic/racial discrimination, they reported greater same-day daytime dysfunction; 

• on days in which adolescents had greater daytime dysfunction, they also reported more negative mental health outcomes (i.e., negative mood, anxious mood, rumination, and somatic symptoms) and less positive mood the next day; 

• adolescents who reported ethnic/racial discrimination in the past 6 months experienced greater daytime sleepiness and greater daily nighttime disturbance; 

• on days in which adolescents had greater daytime sleepiness, they also reported more negative mental health outcomes (i.e., negative mood, anxious mood, rumination, and somatic symptoms) and less positive mood the next day; 

• on days in which adolescents experienced ethnic/racial discrimination, they reported greater same-day nighttime disturbance. Adolescents who reported greater daily nighttime disturbance experienced higher overall levels of negative mental health outcomes (i.e., negative mood, anxious mood, rumination, and somatic symptoms) in the past 2 weeks; 

• adolescents who reported greater daily nighttime disturbance experienced higher levels of negative mental health outcomes (i.e., negative mood, anxious mood, rumination, and somatic symptoms) and less positive mood in the past 2 weeks.

• Group-specific analyses were conducted for the Asian and Latinx subgroups to further interrogate the full sample results. Specifically, these models suggest that discrimination may be more likely to impact daytime sleepiness for Asian youth whereas discrimination may be more likely to impact nighttime disturbances for Latinx youth. Taken together, these additional analyses suggest that there is reason to further explore group-specific analyses in future research.

They add that, “this is the first study to observe that daily indices of sleep/wake problems serve as mediating links between the social stress of ethnic/racial discrimination and mental health. Accordingly, focusing on ways to disrupt this pathway may provide a developmental framework for mitigating the health consequences of ethnic/racial discrimination. Specifically, this study observes that daily sleep experiences can be linked to both daily and longer-term mental health for ethno-racially diverse adolescents.”

“Taken together, across the three sleep/wake indices (i.e., nighttime disturbance, daytime dysfunction, daytime sleepiness) and the five mental health outcomes (i.e., negative mood, anxious mood, rumination, somatic symptoms, positive mood), there was evidence that sleep-related concerns serve as an explanatory pathway through which ethnic/racial discrimination is implicated in mental health problems. What this study contributes is a focus on temporal associations such that daily ethnic/racial discrimination was associated with same-day sleep/wake problems. On days in which adolescents experienced ethnic/racial discrimination, they also reported elevated levels of nighttime disturbance, daytime dysfunction, and daytime sleepiness. These data make clear that discrimination is a public health concern. More importantly, these data also point to the potential to interrupt the impact of ethnic/racial discrimination by focusing on levers of change related to sleep for adolescents. In addition, the study adds to the growing literature about how focusing on sleep health may improve consequent health and development among marginalized youth.”