Reciprocal Relationships Between Exposure to Community Violence and Sleep Problems Across Adolescence

Abstract

Urban adolescents experience high rates of exposure to community violence, which is associated with sleep problems. However, less is known about the prospective relationships between community violence exposure and sleep problems across adolescence. This study investigated reciprocal relationships between community violence exposure and sleep problems across early, middle, and late adolescence. Participants included 84 urban adolescents (50% females, 95% African Americans) who reported on their community violence exposure and sleep problems at mean ages 13, 16, and 17. Results from an autoregressive latent trajectory model with structured residuals showed that exposure to community violence at age 13 predicted more sleep problems at age 16, but violence exposure at age 16 did not predict sleep problems at age 17. Sleep problems did not predict community violence exposure over time. These results point to early adolescence as a vulnerable period for the development of sleep problems in youth exposed to community violence.

Keywords

community violence exposure sleep problems adolescence

By the time they reach middle adolescence, 68% of youth residing in the United States have witnessed violence and 64% have been violently assaulted in their lifetime; additionally, over 30% of adolescents report witnessing violence and victimization in the past year (Finkelhor, Turner, Shattuck, & Hamby, 2015). Community violence exposure is especially prevalent in low-income urban communities with mostly African American residents, where it affects as many as 95% of youth (Gaylord-Harden, Cunningham, & Zelencik, 2011). Exposure to community violence contributes to a number of negative developmental outcomes, including internalizing and externalizing problems, substance use, and low academic achievement (Borofsky, Kellerman, Baucom, Oliver, & Margolin, 2013; Mrug & Windle, 2010; Wright, Fagan, & Pinchevsky, 2013). Some of these effects could be explained by disrupted sleep patterns in youth exposed to violence, as sleep problems contribute to the same negative emotional, behavioral, and academic outcomes as exposure to violence (Quach, Nguyen, Williams, & Sciberras, 2018; Shochat, Cohen-Zion, & Tzischinsky, 2014; Sivertsen, Skogen, Jakobsen, & Hysing, 2015). However, little is known about the relationship between adolescents’ exposure to community violence and sleep problems.

Exposure to community violence may disrupt sleep through trauma symptoms. Indeed, adolescents’ exposure to community violence is associated with post-traumatic stress symptoms, including intrusive thoughts and hyperarousal (Martin, Revington, & Seedat, 2013), which have been shown to contribute to sleep problems over time (Zhou, Wu, An, & Fu, 2014). However, only a handful of studies have linked community violence exposure with sleep among adolescents. In a small cross-sectional study of mostly African American urban adolescents (aged 16–18), exposure to community violence was associated with concurrent sleep disturbances (Cooley-Quille & Lorion, 1999). These results were replicated in another small cross-sectional study of African American early adolescents (Kliewer, Robins, & Borre, 2019). Two larger studies with ethnically diverse samples of early adolescents showed a connection between exposure to community violence and sleep problems 6 months later (Lepore & Kliewer, 2013; Sosnowski, Kliewer, & Lepore, 2016). Finally, exposure to community violence was correlated with more sleep problems across multiple time points within an 18-month period in another study of mostly Latino and African American early adolescents (Kliewer & Lepore, 2015).

Although these studies demonstrate a connection between exposure to community violence and sleep problems, the majority of them have not established a clear temporal relationship between exposure to community violence and subsequent sleep problems, while also accounting for potential confounders. In particular, lower family socioeconomic status (SES) is related to both community violence exposure (Mrug & Windle, 2010) and sleep problems (Mrug, Tyson, Turan, & Granger, 2016). Similarly, earlier pubertal development is associated with more sleep problems in early to middle adolescence (Knutson, 2005), as well as more violent behavior in youth living in disadvantaged neighborhoods (Obeidallah, Brennan, Brooks-Gunn, & Earls, 2004), which is a risk factor for subsequent exposure to community violence (Mrug & Windle, 2009a).

Moreover, it is possible that the relationship between community violence exposure and sleep problems is bidirectional and sleep problems also contribute to community violence exposure through increased externalizing problems. For instance, one reason for insufficient sleep may be staying out late at night roaming the neighborhood, which may directly increase the risk of violence exposure. In addition, adolescent sleep problems predict more antisocial behavior and substance use over time (Chang et al., 2017; Nguyen-Louie et al., 2018), which then increase the risk of experiencing community violence (Mrug & Windle, 2009a, 2009b). Indeed, a bidirectional relationship has been found between sleep problems and externalizing problems in children (Quach et al., 2018). However, no studies have tested the effects of sleep on exposure to community violence. It is also not clear whether the links between sleep and community violence exposure vary across adolescence. One longitudinal study of urban minority adolescents showed decreasing levels of self-reported trauma-related sleep problems across adolescence (Umlauf, Bolland, Bolland, Tomek, & Bolland, 2015), but no studies examined the links between violence exposure (or other traumatic experiences) and sleep problems across different developmental periods.

Current Study

Given the limited research on community violence exposure and sleep in adolescence, this study examines prospective, bidirectional relationships between exposure to community violence and sleep problems. To elucidate possible developmental differences, we examine these links across three time points spanning early, middle, and late adolescence. The study focuses on urban African American youth, who are most affected by community violence (Gaylord-Harden et al., 2011). We hypothesize that community violence exposure will be related to sleep problems concurrently across adolescence. We also expect that community violence exposure will predict more sleep problems over time and that sleep problems will contribute to more community violence exposure.

Methods

Participants and Procedures

Participants were 84 adolescents taking part in the longitudinal Coping with Violence Study. Youth were assessed at three time points (M_ages = 13.36, 16.11, and 17.80; SDs = 0.96, 1.11, and 1.14) and included 50% females, 95% African Americans, 4% Caucasians, and 1% Hispanics. Adolescents were recruited from four public schools serving low-income, urban communities in Birmingham, Alabama. Between 83% and 87% of students at those schools were eligible for free or reduced cost lunch. Information about the study was distributed to students in schools. Interested families returned a completed contact information form (54% return rate) and were later contacted by study staff to schedule individual interviews at a university laboratory. Of the 84 families participating at Time 1, 75 (89%) returned at Time 2 (on average 2.75 years later), and 69 (82%) returned at Time 3 (on average 1.69 years after Time 2). Youth who were lost to attrition were slightly older at Time 1, M = 13.83 vs. 13.25; t(82) = -2.19, p = .031, but did not differ from those who remained in the study on Time 1 community violence exposure, sleep problems, family income, pubertal development, or gender (all p > .256).

At each time point, parents provided informed consent and youth provided assent or consent. Then, parents and adolescents were interviewed separately in private spaces by trained interviewers using computer assisted technology. The interviews took on average about two hours and participants were compensated with a $50 gift card. All procedures were approved by the university Institutional Review Board.

Measures

Community violence exposure

Community violence exposure was measured with the Children’s Report of Exposure to Violence (Cooley, Turner, & Beidel, 1995). At each time point, adolescents responded to 14 items about witnessing violence in their community during the last 12 months where the victim was a stranger (5 items), someone they knew (5 items), or themselves (4 items). Example item is “Did you see a stranger being robbed or mugged in the past twelve months?” Answers ranged from “No” (1) to “Many times” (4) and were averaged (Cronbach’s α = .84, .86, and .94 at Times 1–3). Higher scores indicate greater exposure to community violence.

Sleep problems

Sleep problems were assessed with the Adolescent Sleep Habit Survey (Wolfson & Carskadon, 1998). At each time point, adolescents reported the frequency of 22 sleep problems experienced during a typical week, including disruptions to the wake-sleep cycle (e.g., staying up late), insomnia (e.g., difficulty falling or staying asleep), daytime sleepiness (e.g., falling asleep during the day), parasomnias (e.g., nightmares), sleep disordered breathing (e.g., snoring, gasping for breath), and general sleep quality (e.g., satisfied with sleep; reverse coded). Items were rated on a 5-point scale from “Never” (1) to “Every day” (5), with higher scores indicating more sleep problems. The responses were averaged (Cronbach’s α = .73, .69, and .77 at Times 1–3).

Covariates

Potential covariates included age, gender, family income, and pubertal status. Age was measured in years from parent-reported birthdays and dates of interviews. Family income was reported by parents at Time 1 on a 13-point scale from “$5,000 or less per year” to “$90,000 more per year.” Pubertal status was reported by adolescents at each time point using the Pubertal Development Scale (Petersen, Crockett, Richards, & Boxer, 1988), with Cronbach’s alpha ranging from .61 to .69 for girls and from .66 to .69 for boys.

Statistical Analyses

Descriptive statistics of sleep problems and community violence exposure were computed at each time point, with changes across time points tested with repeated measures analyses of variance (ANOVAs). Pearson’s correlations evaluated bivariate correlations among community violence exposure, sleep problems, and potential covariates (age, gender, family income, and pubertal status). The main analysis involved a single autoregressive latent trajectory model with structured residuals (ALT-SR; Berry & Willoughby, 2017) estimating the latent trajectories of community violence exposure and sleep problems, respectively, across the three time points, as well as the bidirectional relationships between residual levels of community violence exposure and sleep problems across adjacent time points, continuity of residual scores within each construct, and associations between the residual scores within each time point. Because the model was too complex for the number of variables and thus was underidentified (had negative degrees of freedom) and could not be estimated, the slope latent factors were removed based on the results of latent growth curve modeling showing non-significant means and variances of these slope effects. Due to the limited sample size, only covariates related to main variables were included in the model (age and pubertal status). Specifically, age and pubertal status at Time 2 were modeled as predictors of Time 2 residual community violence exposure and sleep problems, whereas age and pubertal status at Time 3 were modeled as predictors of Time 3 residual community violence exposure and sleep problems. The intercept-only ALT-SR model was estimated in Mplus version 8.4 using Full Information Maximum Likelihood (FIML) with robust standard errors to account for violations of multivariate normality. The FIML analysis uses all available data, preserves the full sample size (N = 84), and minimizes bias when data are missing at random (Wothke, 2000). To facilitate interpretation of the results, standardized path coefficients are reported as indicators of effect size.

Results

Descriptive statistics and correlations for community violence exposure and sleep problems at each time point are listed in Table 1. The most commonly endorsed violence exposure items (endorsed as one to many times in the last year) were seeing somebody you know being beaten up (21%), yourself being beaten up (19%), seeing somebody you don’t know being beaten up (15%), and seeing somebody you know being chased or seriously threatened (12%). The most commonly reported sleep problems (as some of the time to most of the time) were feeling tired and sleepy during the day (90%), needing multiple reminders to get up in the morning (79%), going to bed because could not stay awake any longer (77%), and taking naps during the day (73%). Average (and median) annual family income at Time 1 was $20,001 to $25,000, and the average pubertal development across the three time points was 2.64, 3.09, and 3.29, corresponding to pubertal development between starting (Score 2), being underway (Score 3), and being completed (Score 4).

Table 1.

Descriptives and Correlations.

Variables	M (SD)	1.	2.	3.	4.	5.	6.	7.	8.	9.
1. Community violence exposure, T1 (n = 80)	1.15 (0.29)	—
2. Community violence exposure, T2 (n = 69)	1.14 (0.28)	.55**	—
3. Community violence exposure, T3 (n = 63)	1.20 (0.41)	.46**	.43**	—
4. Sleep problems, T1 (n = 84)	1.90 (0.42)	.54**	.26*	.11	—
5. Sleep problems, T2 (n = 75)	1.88 (0.34)	.33**	.25*	.06	.40**	—
6. Sleep problems, T3 (n = 68)	1.96 (0.44)	.23	.19	.31*	.34**	.51**	—
7. Age, T2 (n = 75)	16.11 (1.11)	.12	−.04	.18	−.03	−.11	.08	—
8. Age, T3 (n = 69)	17.80 (1.14)	.17	.02	.24	.01	−.13	.18	.93**	—
9. Pubertal status, T2 (n = 75)	3.09 (0.49)	−.30*	−.16	−.03	−.26*	−.14	−.10	.34**	.28*	—
10. Pubertal status, T3 (n = 68)	3.29 (0.45)	−.14	−.14	−.08	−.05	−.14	.00	.12	.13	.44**

Note. Pubertal status differed by sex at both T2 and T3 (p < .05). Females had average pubertal status of 3.21 (SD = 0.55) and 3.47 (SD = 0.44) at Times 2 and 3; males had lower average pubertal status than females at 2.96 (SD = 0.38) and 3.08 (SD = 0.07) at Times 2 and 3.

p < .05. **p < .01.

Repeated-measures ANOVAs indicated no differences across time for either community violence exposure, F(2, 108) = 1.36, p = .261, N = 55, or sleep problems, F(2, 134) = 1.33, p = .269, N = 68. Of the covariates, only pubertal status was correlated with the variables of interest. Youth with more advanced pubertal development reported less community violence exposure (r = -.40, p = .011) and fewer sleep problems (r = -.26, p = .025). Age, gender, and family income were not significantly correlated with either community violence exposure or sleep problems at any time points (all p > .05). Therefore, only pubertal status and age (due to its relationship to pubertal status) were included in the main model.

The intercept-only ALT-SR model had an excellent fit to the data, χ²(9) = 8.70, p = .465, comparative fit index (CFI) = 1.00, root mean square error of approximation (RMSEA) = 0.00, and standardized root mean residual (SRMR) = 0.04. As shown in Figure 1, after accounting for each person’s average levels of community violence exposure and sleep problems with the random intercept effects, the residual autoregressive paths were not significant (as would be expected). Residual community violence exposure (i.e., deviation from each person’s overall average) uniquely predicted residual sleep problems at Time 2 (β = 0.80, p = .006, large effect), indicating that youth who were exposed to more community violence at Time 1 than was typical for them over the three time points experienced more sleep problems at Time 2 than was typical for them. Residual community violence exposure at Time 2 did not predict residual sleep problems at Time 3, and residual sleep problems did not predict residual community violence exposure over time at any time point. The covariance between residual community violence exposure and residual sleep problems was significant and positive at each time point (Time 1: β = 0.74, p < .001; Time 2: β = 0.74, p = .044; Time 3: β = 0.55, p = .029; all large effects), suggesting that youth experienced more sleep problems than was typical for them at each time point when they experienced more community violence exposure than was typical for them. To evaluate whether the residual covariance at Time 3 was smaller compared to Times 1 and 2, a constrained model was fit with all three covariances constrained to be equal. Satorra-Bentler scaled chi-square difference test comparing the original and constrained models was significant, Δχ²(1) = 8.75, p = .003, indicating that the covariance was smaller at Time 3 compared to Times 1 and 2. Among the covariates, only higher pubertal development predicted more sleep problems at Time 2 (β = 0.56, p = .024, large effect).

Figure 1.

Intercept-only autoregressive latent trajectory model with structured residuals (ALT-SR) of bidirectional relationships between community violence exposure and sleep problems during adolescence.

Discussion

This prospective study evaluated reciprocal relationships between exposure to community violence and sleep problems from early to late adolescence among urban, mostly African American adolescents. The results showed strong associations between community violence exposure and sleep problems from early to late adolescence, and these were even stronger in early and middle adolescence compared to late adolescence. In addition, exposure to community violence predicted an increase in sleep problems over time, with a large effect, but only in early adolescence. Finally, sleep problems did not predict exposure to community violence over time.

Overall, the results point to early adolescence as a vulnerable time for sleep disruption in youth exposed to community violence. Although the reasons for this vulnerability were not assessed in this study, other research documents puberty-driven changes in circadian rhythm, sleep homeostasis, and sleep architecture that occur at this time (Tarokh, Saletin, & Carskadon, 2016) that may make sleep quality more vulnerable to disruption. Alternatively, this vulnerability may reflect developmental shifts in less adaptive emotion regulation and coping skills during early adolescence (Cracco, Goossens, & Braet, 2017) that may make it more difficult to manage the intrusive thoughts and hyperarousal following trauma. Social constraints in talking about violence exposure also contribute to more intrusive thoughts and disrupted sleep (Kliewer & Lepore, 2015), and perhaps are also higher in early adolescence compared to later periods.

Prior research points to sleep problems as one mechanism through which exposure to violence affects developmental outcomes. In particular, sleep problems mediated the prospective effect of community violence exposure or victimization on lower academic achievement, delinquency, and substance use in early adolescents (Lepore & Kliewer, 2013; Sosnowski et al., 2016). Similarly, inadequate sleep mediated the effects of exposure to interparental violence on adolescents’ depressive symptoms (Nowakowski, Choi, Meers, & Temple, 2016). Indeed, poor sleep has been proposed as a key mediator explaining both psychological and health problems in youth exposed to traumatic events, such as violence (Spilsbury, 2009). Future studies should examine sleep problems as a mediator of emotional and health problems experienced by adolescents exposed to community violence, together with possible moderating factors that may attenuate these effects, such as social support, social constraint, and emotion regulation (Kaynak, Lepore, & Kliewer, 2011; King & Mrug, 2018).

The present findings suggest that early adolescents exposed to community violence are more likely to experience concurrent and subsequent sleep problems than older youth, and thus may especially benefit from interventions targeting sleep quality. Sleep interventions using cognitive behavioral and mindfulness components are effective in improving perceived sleep quality in early adolescents, with downstream effects on improved behavior, attention, and social functioning (Blake et al., 2017). Interventions that help youth process their traumatic experiences, such as school-based expressive writing interventions (Kliewer et al., 2011) or trauma-informed cognitive behavioral approaches (Mendelson, Tandon, O’Brennan, Leaf, & Ialongo, 2015), may also be helpful in reducing trauma symptoms and subsequent sleep disturbances. More research is needed to identify specific intervention components that are most beneficial in reducing the negative impact of violence exposure on adolescents’ sleep, emotions, and behavioral functioning.

The results of this study should be interpreted in the context of its strengths and limitations. Key strengths include the longitudinal design with three time points spanning early to late adolescence, as well as identical assessments of sleep problems and community violence exposure over time. However, the study was limited by subjective measure of sleep quality, a small and homogeneous sample, and long lags between the time points. There was also some attrition as is typical in all longitudinal studies, with older youth being more likely to drop out of the study. Although the main analysis utilized available data from all 84 participants, preliminary analyses (e.g., repeated-measured ANOVAs, correlations) were affected by attrition and thus some of these analyses had smaller sample sizes and less power than others. With sample size of 84, the power to detect medium and large effects was sufficient (above 0.93), but the power to detect small effects was low (0.25). Larger samples will be needed to detect small-sized effects in future research. In addition, because of the modest sample size and high complexity of the autoregressive latent trajectory model, some medium- to large-sized paths (0.52–0.77) were not statistically significant. Thus, replication of these results with larger samples will be essential to confirm the role of community violence exposure in adolescents’ sleep problems.

As self-reported measures can be biased (e.g., by social desirability or problems with recall), future studies on community violence exposure and sleep would benefit from including objective assessments of both community violence and sleep, for example using actigraphy or electroencephalogram (EEG). In addition, using sleep diaries may be less susceptible to recall bias than global measures of sleep quality used in this study. A number of unmeasured variables, such as moving to a different community, financial hardship, family dynamics, preexisting vulnerabilities to sleep problems, psychopathology, or other factors related to community violence exposure or sleep may have affected the findings, and should be included in future studies. The findings should also be replicated in larger, more diverse samples, and with shorter lags between assessments (e.g., 1 year) to provide more fine-grained understanding of developmental differences in the relationships between community violence exposure and sleep.

In conclusion, this study points to early adolescence as a vulnerable period for the development of sleep problems in urban youth exposed to community violence. More research is needed to understand the role of sleep problems in developmental outcomes associated with exposure to community violence. Future research should also identify protective factors that foster resilience and attenuate the negative impact of violence exposure on sleep. Finally, more work is needed to develop and disseminate interventions that would promote sleep quality and positive adjustment in urban youth exposed to community violence.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Sylvie Mrug

Author Biographies

Sylvie Mrug, PhD, is a professor of psychology at the University of Alabama at Birmingham. Her research focuses on risk and protective factors for emotional and behavioral problems in adolescence.

Catheryn A. Orihuela, PhD, is a postdoctoral fellow in psychology at the University of Alabama at Birmingham. She studies the role of neighborhood characteristics in youth developmental outcomes.

Alex Veerasammy, BS, is a graduate student in Industrial-Organizational Psychology at George Mason University. He completed a research internship at the University of Alabama at Birmingham where he studied the impact of violence exposure on adolescents.

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