Sleep Apnea Among Gulf War Veterans: An Examination of VA Utilization Rates, Treatment Initiation, and Health Outcomes.

OBJECTIVES: Obstructive sleep apnea (OSA) among veterans is frequently underdiagnosed and undertreated. The present study sought to: 1) characterize the prevalence and rate of treatment of OSA among VA users and non-users and 2) examine the associations between diagnosed or probable OSA and key physical and mental health outcomes. METHODS: Gulf-War I-era Veterans were recruited as part of a national survey assessing mental and physical health concerns, healthcare needs, and healthcare utilization. OSA diagnoses were self-reported while sleep apnea risk was assessed via the STOP-Bang. Veterans also completed questionnaires assessing overall health, pain, depression, PTSD, and psychosocial functioning. RESULTS: 1,153 veterans were included in the present analyses (Mean age = 58.81; 21.84% female). Compared to non-VA healthcare users, veterans receiving care at the VA were more likely to have been diagnosed with OSA (p < .001) and report receiving treatment for OSA (p = .005). Compared to veterans at low risk for OSA, veterans at elevated risk reported higher levels of pain (p = .001), depression (p = .02), and poorer psychosocial functioning (p < .001). CONCLUSIONS: OSA diagnoses appear to be more common among VA healthcare users. Findings suggest that OSA remains underdiagnosed and associated with important physical and mental health consequences. Additional screening for OSA, especially among non-VA clinics, is warranted.

Cannabis use and suicide risk among Gulf War veterans.

Cannabis use has been indicated as a risk factor for suicide in veterans. This study of Gulf War veterans tested the relationship between self-report past year cannabis use and (a) past year suicidal ideation and (b) risk for suicidal behavior. Data were from a national sample (N = 1126) of Gulf War veterans. Logistic regression models indicated cannabis use was associated with past year suicidal ideation and elevated risk for suicidal behavior, independent of key covariates. In corroboration with research on other military populations, this study indicates a potentially concerning association between cannabis use and suicide risk in Gulf War veterans.

Reciprocal Effects Between Depressive Symptoms and Pain in Veterans over 50 Years of Age or Older.

OBJECTIVE: Depression and chronic pain are major problems in American veterans, yet there is limited long-term research examining how they relate to one another in this population. This study examined the relationship between depressive symptoms and pain in U.S. veterans 50 years of age or older. METHODS: This study used data on veterans from the 2002-2016 waves of the Health and Retirement Study (n = 4,302), a large-scale observational study of Americans 50 years of age or older. Measures included a short form of the Center for Epidemiologic Studies Depression scale and two items assessing the presence and degree of pain. Analyses included random-intercept cross-lagged panel models (RI-CLPM). RESULTS: In the RI-CLPM, there were roughly equivalent cross-lagged effects between depressive symptoms and pain. There was also evidence that depressive symptoms and pain have a trait-like component and that these trait-like characteristics are associated. CONCLUSIONS: These findings indicate that depressive symptoms and pain in veterans are stable characteristics in American veterans 50 years of age or older. There appear to be reciprocal effects between the two, whereby deviations in one's typical depressive symptoms predict subsequent deviations in one's pain level and vice versa; however, the size of these effects is very small. These findings suggest that clinicians should treat both depressive symptoms and pain, rather than assume that treatment benefits in one domain will lead to major benefits in another.

Disentangling the Longitudinal Relationship between Loneliness and Depressive Symptoms in U.S. Adults Over 50.

OBJECTIVES: A seminal study on loneliness and depression suggested that loneliness influences depression more than the reverse. However, the study's analytic method has since been criticized for failing to account for the trait-like nature of variables. This study aimed to examine the longitudinal relationship between loneliness and depressive symptoms while accounting for the trait-like nature of both variables. METHODS: Data (n = 16,478) came from the Health and Retirement Study (2006-2016). Measures included the Hughes Loneliness Scale and a modified Center for Epidemiologic Studies Depression scale (loneliness item omitted). Analyses consisted of random intercepts cross-lagged panel models (three time-points evenly spaced across eight years). RESULTS: There was evidence that loneliness and depressive symptoms are trait-like and these trait-like components are strongly associated. There was not evidence of cross-lagged effects between loneliness and depressive symptoms. CONCLUSIONS: A tendency toward loneliness corresponded with a tendency toward depressive symptoms. However, deviations in one's typical level of loneliness did not predict deviations in one's typical level of depressive symptoms or vice-versa. These findings do not support past assertions that loneliness shapes subsequent depression more than the reverse. CLINICAL IMPLICATIONS: By middle to late adulthood, loneliness and depressive symptoms are trait-like phenomena that are strongly associated.

Models of Trauma Exposure, Depression, and Suicidality in Safety-Net Primary Care.

Suicidality is a major public health concern, particularly for low-income, trauma-exposed patients with limited access to mental health providers. However, limited research has modeled pathways of suicidality in safety-net primary care samples. Patients (N = 207) in a safety-net primary care clinic completed measures of childhood and adult trauma exposure, depression, and suicidality. Participants (M age = 44.8 years, SD = 11.6), were 60.4% male, 63.8% Black/African American, and predominantly low-income (i.e., 69.1% reported an annual income less than $5,000 USD). Half of the sample reported at least four childhood traumatic events (M = 3.9 events, SD = 3.0) and approximately three adult traumatic events (M = 3.0 events, SD = 2.1). Most participants (82.1%) reported significant depressive symptoms, and 43.5% endorsed recent suicidality. Models showing the mediational effect of depression on the association between trauma exposure and suicidality, ß = .20, B = 0.23, SE = 0.05, 95% CI [0.16, 0.32], and the moderational effect of trauma exposure on the association between depression and suicidality, ß = .16, B = 0.20, SE = 0.08, p = .007, were both supported. These results underscore the high prevalence of trauma exposure, depression, and suicidality in a safety-net primary care sample. They also highlight the pervasiveness and complexity of suicidality in low-income primary care patients, emphasize the importance of trauma-informed suicide assessment, and identify trauma sequelae and depression as potential treatment targets to reduce suicidality.

Sleep Disturbance Mediates the Association Between Loneliness and Health in Older Americans.

BACKGROUND: As the research documenting loneliness as a risk factor for morbidity and mortality continues to grow, it becomes increasingly critical to understand the mechanics of this relationship. This study assessed whether sleep disturbance mediates the relationship between loneliness and health. METHOD: Data came from the 2006, 2010, and 2014 waves of the Health and Retirement Study, a longitudinal study of older Americans; participants ≥ 65 who completed the Psychosocial and Lifestyle Questionnaire in 2006 were included (n = 5067). Measures include the Hughes loneliness scales, a modified version of the Jenkins sleep scale, and self-reported health. Cross-lagged mediation models (i.e., path analysis) were used to model the relationships between loneliness, sleep disturbance, and self-reported health over the 8-year span. RESULTS: Loneliness predicted subsequent sleep disturbance, which in turn predicted subsequent self-reported health. Moreover, there was evidence of both direct and indirect effects (via sleep disturbance) of loneliness on self-reported health. These effects remained after controlling for demographics, isolation, and depression. CONCLUSION: Sleep disturbance partially mediates the relationship between loneliness and self-reported health over 8 years. These findings are not attributable to isolation or depression. Further research is necessary to develop and assess a more comprehensive model of how loneliness shapes health. This study indicates that targeting sleep disturbance may mitigate the health risks of loneliness in older Americans.

Insomnia Disorder and Behaviorally Induced Insufficient Sleep Syndrome: Prevalence and Relationship to Depression in College Students.

Background: College students are at increased risk for sleep disorders, including insomnia disorder and obtaining less than 6.5 hr of sleep per night by choice, or behaviorally induced insufficient sleep syndrome (BIISS). These disorders can have deleterious daytime consequences, including depression. This study aims to establish the prevalence of insomnia and BIISS disorders and examine associations of insomnia and BIISS with other sleep characteristics and depression. Methods: A subset of data from Spit for Science, a college risk behaviors and health study (n = 989) was used. Insomnia and BIISS were defined as mutually exclusive disorders, based on diagnostic criteria. Results: A majority (68%) of students were categorized as normal sleepers, followed by insomnia (22%), and BIISS (10%). Sleep duration was comparable between BIISS and insomnia, while daytime sleepiness was significantly higher in BIISS, and sleep latency was longer in insomnia (m = 44 vs. m = 13 min). Insomnia was associated with the highest depression symptoms, followed by BIISS, and normal sleep, controlling for demographics. Insomnia was associated with twice the risk of moderate or higher depression compared to normal sleep (CI: 1.60, 2.70, p < .001). Conclusion: These findings highlight the sleep difficulties endemic to college populations. Further, this study provides the first prevalence estimation of BIISS in college students and the first comparison of insomnia and BIISS on sleep characteristics and depressive symptoms. This study underscores the importance of targeted screening and intervention to improve both sleep and depression in this vulnerable population.

Analysis of injuries from the Army Ten Miler: A 6-year retrospective review.

A number of long-distance running events are held each year in the United States; the Army Ten Miler (ATM) is one such race held annually in Washington, DC. The purpose of the present study was to retrospectively analyze medical encounters for runners participating in the ATM from 1998 to 2004. Of the estimated 91,750 runners over the 6-year period, 73,100 participants finished the race and were included in the data analysis. Demographic and injury data were collected from medical records of participants who received medical care while participating in the ATM, and injury-related factors were assessed. The most common category of injury was musculoskeletal (44%), followed by medical-related problems (27%) and dermatological injuries (27%). Similar to marathon and ironman races, ATM injury rates correlate with race-day temperature and dew point. Overall, however, the injury rates observed at the ATM were relatively low compared to those reported for longer distance events. Finally, we detail the medical coverage provided at the ATM, as this coverage could be used as a guide for similarly distanced races.

During roof-to ladder transitions, walk-through extensions modify required friction direction.

Severe and fatal falls involving ladders commonly occur during transitions across the ladder and another support surface. Slipping is a common initiating event in ladder falls. This study characterized the friction requirements and body kinematics of descending roof-to-ladder transitions with and without a walk-through extension. Healthy adults who regularly climb ladders (n = 17) completed descending roof-to-ladder transitions, while foot-rung kinetics and body kinematics were recorded. The peak required coefficient of friction (RCOF) with respect to the plane of the shoe sole was calculated. The RCOF and body angle were calculated using their resultant values and projections in the frontal and sagittal planes. Foot angle was calculated in the sagittal plane. Repeated-measures ANOVA determined that compared to a walk-through ladder, a traditional ladder was associated with a higher RCOF in the medial-lateral (ML) direction (F1,16 = 190.07, p < 0.001) and a lower RCOF in the anterior-posterior (AP) direction (F1,16 = 11.02, p = 0.004), but had no significant relationship with the resultant RCOF (F1,16 = 0.098, p = 0.76). Spearman's rho tests performed across all testing configurations identified significant associations between foot angle and overall RCOF (rs = -0.724, p < 0.001), foot angle and AP RCOF (rs = -0.871, p < 0.001), and frontal plane body angle and ML RCOF (rs = 0.782, p < 0.001). Clustering in the data suggests that ladder attachments reduced frontal plane kinematics, which altered the direction of RCOF by reducing the medial-lateral component. These results have implications for designing rungs with good friction in multiple directions and the potential for body position monitoring in ladder tasks.

Validating the ability of a portable shoe-floor friction testing device, NextSTEPS, to predict human slips.

Measuring shoe-floor friction is critical for assessing the safety of footwear products. Portable devices for measuring coefficient of friction (COF) are needed. This study introduces such a device and evaluates its ability to predict human slip events across shoe designs. A portable device (18 kg) was utilized to measure 66 unique shoe-floor-fluid coefficients of friction (COF). Consistent with the shoes, flooring, and fluid contaminants from the COF tests, participants (n = 66) were unexpectedly exposed to the fluid while walking. Slip predictions were made based on a separate training data set. Slip predictions were made prospectively and using logistic regression analyses. The slip predictions were valid (p < 0.001), 91% sensitive, and 64% specific. The logistic regression fit also revealed that the COF values predicted slip outcomes (p = 0.006). This device is expected to expand the capacity of researchers, product developers, forensic engineers, and safety professionals to prevent slips and enhance human safety.

Mobile health contingency management for smoking cessation among veterans experiencing homelessness: A comparative effectiveness trial.

Tobacco cessation is reduced in U.S. military veterans experiencing homelessness. Mobile contingency management (mCM) is a promising treatment for tobacco use among populations experiencing homelessness, but past CM studies have largely been small, have relied on in-person follow-up, and/or lacked long-term biochemically verified abstinence measures. Veterans who smoked and were experiencing homelessness (N = 127) were randomly assigned to mCM treatment (4 weeks of mCM, 5 weeks of telehealth counseling, and the option of 12 weeks of pharmacotherapy) or VA standard care (3 biweekly group sessions and clinically appropriate pharmacotherapy), and all participants were randomly assigned to a $100 longer-term financial incentive for abstinence at 3-month follow-up. Participants were followed at 3-, 6-, and 12-months post-randomization, with the a priori main outcome designated as biochemically verified prolonged abstinence (with lapses) at 6-month follow-up. At 6-months, participants in the mCM group were significantly more likely to meet criteria for prolonged abstinence (OR = 3.1). Across time points, veterans in the mCM group had twice the odds of prolonged abstinence as those in the standard care group. However, by the 12-month follow-up, there was no statistically significant group difference in abstinence. Cost-effectiveness analysis indicated a modest increase in cost ($1,133) associated with an increase of one quality-adjusted life year saved for the intervention compared to standard care. mCM is a cost-effective approach to smoking cessation among veterans experiencing homelessness. Considering waning potency of this and other tobacco cessation interventions at 12-month follow-up, it is crucial to implement strategies to sustain abstinence for individuals experiencing homelessness.

Advanced rehabilitation techniques for the multi-limb amputee.

Advances in combat casualty care have contributed to unprecedented survival rates of battlefield injuries, challenging the field of rehabilitation to help injured service members achieve maximal functional recovery and independence. Nowhere is this better illustrated than in the care of the multiple-limb amputee. Specialized medical, surgical, and rehabilitative interventions are needed to optimize the care of this unique patient population. This article describes lessons learned at Walter Reed National Military Medical Center Bethesda in providing advanced therapy and prosthetics for combat casualties, but provides guidelines for all providers involved in the care of individuals with amputation.

Investigating the Influence of Spatiotemporal Gait Characteristics on Shoe Wear Rate.

OCCUPATIONAL APPLICATIONSWe investigated the association between shoe wear rate and several metrics describing an individual's spatiotemporal gait characteristics (cadence, step length, and preferred walking speed). No associations were found, indicating that alternative metrics should be investigated to predict the individualized rate at which workers wear down shoe tread.

TECHNICAL ABSTRACTBackground Shoe wear has been associated with increased slips and falls in the workplace. People wear down shoe tread at different rates; therefore, individualized shoe replacement timelines could improve resource targeting for organizations that use time as a basis for shoe replacement. Previous work has found that the shoe-floor kinetics, such as the friction requirements of walking, correlate with shoe wear rate. The use of easily measured metrics such as cadence, step length, or preferred walking speed to predict wear has not yet been investigated despite their relationship with friction requirements.Purpose This study seeks to determine the association between shoe wear rate and gait spatiotemporal characteristics.Methods Thirteen participants completed a longitudinal shoe wear study that consisted of a gait assessment followed by prolonged shoe wear in two pairs of slip-resistant shoes. The gait assessment was comprised of dry level-ground walking trials; kinematic and kinetic data were collected through optical motion capture and force plates. The participants' mean cadence, step length, and preferred walking speed were calculated. The participants then wore their shoes at work; the shoe wear rate was determined by measuring the periodic volumetric tread loss during this wear-at-work portion of the study.Results Three linear regression models found no significant association between the chosen gait metrics and the shoe wear rate.Conclusions The lack of an association between the spatiotemporal gait characteristics and shoe wear rate indicates that these factors may not explain the differences in wear rate between participants. This negative finding suggests that other measures such as the required coefficient of friction are better for individualizing footwear replacement guidelines.

A National Study of Zoom Fatigue and Mental Health During the COVID-19 Pandemic: Implications for Future Remote Work.

Overuse of videoconferencing for work may contribute to what has been called "Zoom fatigue": feeling anxious, socially isolated, or emotionally exhausted due to lack of social connection. Given implications for employee well-being, this study investigated Zoom fatigue at work and its potential link to mental health symptoms. A national survey of mental health symptoms was conducted in the United States during the COVID-19 pandemic in August 2020. Adults (n = 902) endorsing a shift at work to videoconferencing completed an online survey; survey criteria included an age minimum of 22 years and reported annual gross income of <$75,000. Statistical raking was employed to weight the sample using U.S. census data on geographic region, age, gender, race, and ethnicity. A three-item Zoom Fatigue Scale measuring perceived stress, isolation, and depression associated with videoconferencing at work showed good internal consistency (α = 0.85). Higher scores on this scale were related to being married, nonwhite race, post-high school education, severe mental illness, greater loneliness, lower social support, lacking money for food, and more weekly videoconference calls. Depressive symptoms demonstrated a significant association with Zoom fatigue, even when adjusting for demographic, psychosocial, and clinical covariates. The study findings indicated that employers and employees should consider a complex array of individual-level and environment-level factors when assessing how videoconferencing at work may engender stress, social isolation, and emotional exhaustion. This impact could adversely impact mental health, work productivity, and quality of life, even after the COVID-19 pandemic.

Comparing psychosocial functioning, suicide risk, and nonsuicidal self-injury between veterans with probable posttraumatic stress disorder and alcohol use disorder.

BACKGROUND: Posttraumatic stress disorder (PTSD) and alcohol use disorder (AUD) are each common among Unites States (U.S.) military veterans and frequently co-occur (i.e., PTSD+AUD). Although comorbid PTSD+AUD is generally associated with worse outcomes relative to either diagnosis alone, some studies suggest the added burden of comorbid PTSD+AUD is greater relative to AUD-alone than to PTSD-alone. Furthermore, nonsuicidal self-injury (NSSI) is more common among veterans than previously thought but rarely measured as a veteran psychiatric health outcome. This study sought to replicate and extend previous work by comparing psychosocial functioning, suicide risk, and NSSI among veterans screening positive for PTSD, AUD, comorbid PTSD+AUD, and neither disorder. METHODS: This study analyzed data from a national sample of N = 1046 U.S. veterans who had served during the Gulf War. Participants self-reported sociodemographic, functioning, and clinical information through a mailed survey. RESULTS: Veterans with probable PTSD+AUD reported worse psychosocial functioning across multiple domains compared to veterans with probable AUD, but only worse functioning related to controlling violent behavior when compared to veterans with probable PTSD. Veterans with probable PTSD+AUD reported greater suicidal ideation and NSSI than veterans with probable AUD, but fewer prior suicide attempts than veterans with probable PTSD. LIMITATIONS: This study was cross-sectional, relied on self-report, did not verify clinical diagnoses, and may not generalize to veterans of other military conflicts. CONCLUSIONS: Findings underscore the adverse psychiatric and functional outcomes associated with PTSD and comorbid PTSD+AUD, such as NSSI, and highlight the importance of delivering evidence-based treatment to this veteran population.

Characteristics of phantom limb pain in U.S. civilians and service members.

OBJECTIVES: The population of Americans with limb loss is on the rise, with a different profile than in previous generations (e.g., greater incidence of amputation due to diabetes). This study aimed to identify the key characteristics of phantom limb sensation (PLS) and pain (PLP) in a current sample of Americans with limb loss. METHODS: This cross-sectional study is the first large-scale (n=649) study on PLP in the current population of Americans with limb loss. A convenience sample of military and civilian persons missing one or more major limbs was surveyed regarding their health history and experience with phantom limb phenomena. RESULTS: Of the participants surveyed, 87% experienced PLS and 82% experienced PLP. PLS and PLP typically first occurred immediately after amputation (47% of cases), but for a small percentage (3-4%) onset did not occur until over a year after amputation. Recent PLP severity decreased over time (ß=0.028, 95% CI: -0.05-0.11), but most participants reported PLP even 10 years after amputation. Higher levels of recent PLP were associated with telescoping (ß=0.123, 95% CI: 0.04-0.21) and higher levels of pre-amputation pain (ß=0.104, 95% CI: 0.03-0.18). Those with congenitally missing limbs experienced lower levels of recent PLP (t (37.93)=3.93, p<0.01) but there were no consistent differences in PLP between other amputation etiologies. CONCLUSIONS: Phantom limb phenomena are common and enduring. Telescoping and pre-amputation pain are associated with higher PLP. Persons with congenitally missing limbs experience lower levels of PLP than those with amputation(s), yet PLP is common even in this subpopulation.

Mental health and demographic correlates of loneliness after left ventricular assist device implantation.

Loneliness is a risk factor for coronary heart disease, stroke, and hospital readmission, yet there are no studies to our knowledge examining loneliness in left ventricular assistance device (LVAD) patients. This study used a cross-sectional survey design on a convenience sample of LVAD patients (n = 73). Logistic regression was used to identify demographic correlates of loneliness; linear regression was used to examine the relationship between loneliness and both stress and depression. Loneliness was measured via the loneliness item from the Center for Epidemiologic Studies Depression (CESD), depression via the CESD (excluding the loneliness item), and stress via the Perceived Stress Scale. In bivariate analyses, older age (OR per year = 0.958, 95%CI = 0.919-0.998) and being partnered (OR = 0.245, 95%CI = 0.083-0.724) were associated with less loneliness. In the multivariate model, there was an interaction effect between age and partnership (p = 0.0212), where older age was protective against loneliness for non-partnered, but not partnered, patients. Higher loneliness was associated with higher stress (ß = 0.484, B = 5.687, 95%CI = 3.195-8.178) and depression (ß = 0.618, B = 7.544, 95%CI = 5.241-9.848). Patients who are not partnered and younger may be at increased risk of loneliness after LVAD. Loneliness in turn is associated with higher stress and depression. Longitudinal research is necessary to speak to direction of effects.

Sleep disturbance and pain in U.S. adults over 50: evidence for reciprocal, longitudinal effects.

OBJECTIVE: To examine the relationship between sleep disturbance and pain over a 14-year period. METHODS: This study used data from the 2002-2016 waves of the Health and Retirement Study (HRS), an observational study of U.S. adults over age 50 (n = 17,756). Sleep disturbance was measured via four items (assessing difficulty falling asleep, staying asleep, and waking up too early as well as restedness) and pain via two items assessing the presence and degree of pain. Analyses consisted of path analysis; more specifically, random intercept cross-lagged panel modeling (RI-CLPM) was used to examine how pain and sleep disturbance predict one another over two-year intervals after accounting for the trait-like nature of both factors. RESULTS: There was evidence of reciprocal effects between sleep disturbance and pain across some, but not all, intervals. Moreover, the latent variables representing the trait-like nature of sleep disturbance and pain both showed significant variance (p < 0.001), indicating stable differences between persons in sleep and pain. These trait-like characteristics were strongly associated (ß = 0.51, p < 0.001). The findings remained after adjusting the model for baseline age, self-reported health, partner status, depression, years of education, and sex. CONCLUSION: Sleep disturbance and pain are stable experiences. Moreover, there was some evidence that sleep disturbance and pain are bidirectionally linked across time among adults over 50, whereby across some intervals deviations in one's typical level of sleep disturbance predicted corresponding deviations in one's typical level of pain and vice versa. Clinically, this comorbidity and potential longitudinal bidirectionality underscore the importance of evidence-based interventions that target both sleep and pain among older individuals. Further studies should replicate these findings by collecting validated and/or objective sleep and pain measures on a more frequent basis.

Isolation, Not Loneliness or Cynical Hostility, Predicts Cognitive Decline in Older Americans.

Objective: To jointly examine isolation, loneliness, and cynical hostility as risk factors for cognitive decline in older adults. Method: Data came from the 2006 to 2012 waves of the Health and Retirement Study (HRS), a longitudinal study of U.S. older adults (age ⩾ 65 years, n = 6,654). Measures included frequency of contact with social network (objective isolation), the Hughes Loneliness Scale (loneliness), a modified version of the Cook-Medley Hostility Inventory (cynical hostility), and a modified version of the Telephone Interview for Cognitive Status (cognitive function). Multilevel modeling (random slope + intercept) was used to examine the association between these factors and trajectories of cognitive function. Results and Discussion: After controlling for demographic characteristics, self-reported health, and functional limitations, loneliness (ß = -.34, 95% confidence interval [CI] = [-0.56, -0.11), and cynical hostility (ß = -.14, 95% CI = [-0.24, -0.04) correlated with lower cognitive function, but none predicted change in cognitive function. Objective social isolation was associated with lower cognitive function (ß = -.27, 95% CI = [-0.41, -0.12]) and steeper decline in cognitive function (ß = -.09, 95% CI = [-0.16, -0.01]).

Loneliness and sleep: A systematic review and meta-analysis.

Despite the mounting evidence linking loneliness with health, the mechanisms underlying this relationship remain obscure. This systematic review and meta-analysis on the association between loneliness and one potential mechanism-sleep-identified 27 relevant articles. Loneliness correlated with self-reported sleep disturbance (r = .28, 95% confidence interval (.24, .33)) but not duration, across a diverse set of samples and measures. There was no evidence supporting age or gender as moderators or suggesting publication bias. The longitudinal relationship between loneliness and sleep remains unclear. Loneliness is related to sleep disturbance, but research is necessary to determine directionality, examine the influence of other factors, and speak to causality.