Megan E. Petrov

Sleep symptoms, race/ethnicity, and socioeconomic position.

STUDY OBJECTIVES Growing evidence indicates sleep is a major public health issue. Race/ethnicity and socioeconomics may contribute to sleep problems. This study assessed whether sleep symptoms were more prevalent among minorities and/or the socioeconomically disadvantaged. DESIGN Cross-sectional. SETTING Epidemiologic survey. PATIENTS OR PARTICIPANTS 2007-2008 National Health and Nutrition Examination Survey (N = 4,081). INTERVENTIONS None. MEASUREMENTS AND RESULTS Sociodemographics included age, sex, race/ethnicity, marital status, and immigration. Socioeconomics included poverty, education, private insurance, and food insecurity. Sleep symptoms assessed were sleep latency > 30 min, difficulty falling asleep, sleep maintenance difficulties, early morning awakenings, non-restorative sleep, daytime sleepiness, snorting/gasping, and snoring. Decreased reported problems for most symptoms were found among minorities, immigrants, and lower education levels. In general, in fully adjusted models, long sleep latency was associated with female gender, being black/African American, lower education attainment, no private insurance, and food insecurity. Difficulty falling asleep, sleep maintenance difficulties, early morning awakenings, and non-restorative sleep were also associated with female gender and food insecurity. Daytime sleepiness was seen in female and divorced respondents. Snorting/gasping was more prevalent among male, other-Hispanic/Latino, and 9(th)- to 11(th)-grade-level respondents. Snoring was prevalent among male, other-Hispanic/Latino, less-educated, and food-insecure respondents. CONCLUSIONS Sleep symptoms were associated with multiple sociodemographic and economic factors, though these relationships differed by predictor and sleep outcome. Also, reports depended on question wording.

Racial and ethnic differences in older adults with knee osteoarthritis.

Knee osteoarthritis (OA) contributes significantly to disability in older individuals, and racial/ethnic minorities are disproportionately affected. The present study aimed to characterize differences in clinical and experimental pain, including pain inhibition, among older African American (AA) and non‐Hispanic white (NHW) subjects with knee OA.

Longitudinal Associations between Objective Sleep and Lipids: The CARDIA Study

STUDY OBJECTIVE To investigate the longitudinal relationships between actigraph-derived sleep duration, fragmentation, and lipid levels. DESIGN AND SETTING Longitudinal data from the Coronary Artery Risk Development in Young Adults Sleep Study (2003-05), an observational cohort at the Chicago site. PARTICIPANTS There were 503 black and white adults, ages 32-51 years, with no prior history of cardiovascular disease. INTERVENTIONS N/A. MEASUREMENT AND RESULTS Sleep duration and fragmentation were measured using 6 days of wrist actigraphy. Sleep quality was measured with the Pittsburgh Sleep Quality Index. The outcome variables, measured at 3 examinations over 10 years (Baseline [2000-01], 5-year [2005-06], and 10-year follow-up [2010-11]), were total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides (TG), and TC/HDL ratio. The associations between each sleep parameter and 10-year change in lipids were analyzed with generalized estimating equation models adjusting for relevant confounders. After adjustment, each hour increase in sleep duration was significantly associated with higher TC (5.2 mg/dL, 95%CI: 1.7, 8.6) and LDL (3.4 mg/dL, 95%CI: 0.2, 6.6) in the total sample, a 1.1 mg/dL increase in TG (95%CI: 1.0, 1.1) among men, and a borderline significant greater odds for a TC/HDL ratio ≥ 5 among men (OR: 1.37, 95%CI: 0.99, 1.90). Overall, sleep fragmentation and sleep quality scores were not associated with change in lipids. CONCLUSIONS Beyond relevant covariates, over a 10-year follow-up, longer objective sleep duration was longitudinally and significantly associated with a poorer lipid profile. Greater objective sleep fragmentation and self-reported poor sleep quality were not related to a poorer lipid profile.

Differences in sleep between black and white adults: an update and future directions

Meta-analyses and other previous reviews have identified distinct ethnic/racial differences in the quantity, quality, and propensity for sleep disorders between black and white adults. The present article reviews the meta-analytic evidence along with recent epidemiological, community, and clinical studies to clarify what is known and not known about sleep differences between these two groups. Black individuals tend to have poorer sleep continuity and quality, excessively short or long sleep duration, greater sleep variability, and greater risk of sleep apnea than white individuals. The data suggest that these differences are attenuated yet persist in the face of several relevant confounders such as socioeconomic status, occupational factors, neighborhood context, and comorbidities. However, little is known about the mechanisms that explain ethnic disparities in sleep. We propose a conceptual model of potential mediators for future testing as well as other questions in need of investigation.

Prevalence of sleep disorders by sex and ethnicity among older adolescents and emerging adults: Relations to daytime functioning, working memory and mental health ☆

The study determined the prevalence of sleep disorders by ethnicity and sex, and related daytime functioning, working memory, and mental health among older adolescent to emerging adult college students. Participants were U.S.A. undergraduates (N = 1684), aged 17-25, recruited from 2010 to 2011. Participants completed online questionnaires for all variables. Overall, 36.0% of the sample screened positive for sleep disorders with insomnia, restless legs syndrome, and periodic limb movement disorder being the most prevalent. Women reported more insomnia and daytime impairment. African-Americans reported more early morning awakenings and less daytime impairment. Students with insomnia symptoms or restless legs syndrome tended to have lower working memory capacities. Students with nightmares or parasomnias had greater odds for mental disorders. In an older adolescent to emerging adult college student sample, sleep disorders may be a common source of sleep disturbance and impairment. Certain sleep disorders may be associated with lower working memory capacity and poor mental health.

Disrupted sleep is associated with altered pain processing by sex and ethnicity in knee osteoarthritis.

UNLABELLED Studies indicate that improving sleep decreases reported pain in patients with knee osteoarthritis, but it is unclear if this association extends to experimentally induced pain responses. A community-based sample of 88 African American and 52 non-Hispanic white adults (45-76 years) with knee osteoarthritis completed the Insomnia Severity Index and the arousal subscale of the Sleep Hygiene and Practices Scale. Participants underwent quantitative sensory testing, including measures of pain sensitivity and facilitation at the knee, and pain inhibition. Outcomes were analyzed with multiple Tobit hierarchical regression models, with adjustment for relevant covariates. Ethnicity and sex by sleep interactions were also entered into the models. After covariate adjustment, main associations were not observed. However, sex interacted with insomnia severity to predict greater temporal summation of heat and punctate pressure pain among women and lower heat temporal summation among men. Men and women who engaged in frequent arousal-associated sleep behaviors demonstrated higher and lower heat temporal summation, respectively. Non-Hispanic whites with greater insomnia severity displayed lower pressure pain thresholds and pain inhibition. Our findings are the first to demonstrate that disrupted sleep is associated with altered pain processing differentially by sex and ethnicity/race among people with knee osteoarthritis. PERSPECTIVE This article presents the association between insomnia severity, maladaptive sleep behaviors, and experimentally induced pain responses among people with knee osteoarthritis. Disrupted sleep was associated with altered pain processing by sex and ethnicity/race. Offering sleep interventions may help ameliorate pain, but treatment may need to be tailored by sex and ethnicity/race.

Objective sleep, a novel risk factor for alterations in kidney function: the CARDIA study

OBJECTIVE To determine the association between objectively measured sleep and 10-year changes in estimated glomerular filtration rate (eGFR). METHODS From 2003 to 2005, an ancillary sleep study was conducted at the Chicago site of the Coronary Artery Risk Development in Young Adults (CARDIA) study. Community-based black and white adults (aged 32-51 years) wore a wrist actigraph for up to six nights to record sleep duration and fragmentation. Sleep quality was measured with the Pittsburgh Sleep Quality Index (PSQI). Participants without history of cardiovascular or chronic kidney diseases, proteinuria, or hypertension at the 2000-2001 CARDIA examination were followed over 10 years (n = 463). eGFR was estimated from serum creatinine (eGFRCr) at the 2000-2001, 2005-2006, and 2010-2011 CARDIA examinations, whereas cystatin-C-estimated eGFR (eGFRCys) was measured at the 2000-2001 and 2005-2006 examinations. Generalized estimating equation regression and linear models estimated the associations of each sleep parameter with changes in eGFRCr and eGFRCys, controlling for cardiovascular and renal risk. RESULTS Sleep parameters were not related to 5-year change in eGFRCys. However, each 1 h decrease in sleep duration was significantly associated with a 1.5 mL/min/1.73 m2 higher eGFRCr [95% confidence interval (CI), 0.2-2.7], and each one-point increase in PSQI was significantly associated with a 0.5 mL/min/1.73 m2 higher eGFRCr (95% CI, 0.04-0.9) over 10 years. CONCLUSION In this community-based sample, shorter sleep and poorer sleep quality were related to higher kidney filtration rates over 10 years.

Sleep Strategies of Night-Shift Nurses on Days Off: Which Ones are Most Adaptive?

Objectives: To determine the off-shift sleep strategies of bi-ethnic night-shift nurses, the relationship between these sleep strategies and adaptation to shift work, and identify the participant-level characteristics associated with a given sleep strategy. Methods: African-American and non-Hispanic White female, night-shift nurses from an academic hospital were recruited to complete a survey on sleep–wake patterns (n = 213). Participants completed the standard shiftwork index and the biological clocks questionnaire to determine sleep strategies and adaptation to night-shift work. In addition, chronotype was determined quantitatively with a modified version of the Munich ChronoType Questionnaire. Most participants worked ~3 consecutive 12-h night-shifts followed by several days off. Results: Five sleep strategies used on days off were identified: (a) night stay, (b) nap proxy, (c) switch sleeper, (d) no sleep, and (e) incomplete switcher. Nap proxy and no sleep types were associated with poorer adaptation to night-shift work. The switch sleeper and incomplete switcher types were identified as more adaptive strategies that were associated with less sleep disturbance, a later chronotype, and less cardiovascular problems. Conclusion: Behavioral sleep strategies are related to adaptation to a typical night-shift schedule among hospital nurses. Nurses are crucial to the safety and well-being of their patients. Therefore, adoption of more adaptive sleep strategies may reduce sleep/wake dysregulation in this population, and improve cardiovascular outcomes.

Relationship of Sleep Duration and Regularity with Dietary Intake among Preschool-Aged Children with Obesity from Low-Income Families

Objective: Diet is a modifiable factor associated with pediatric obesity outcomes, but few studies have evaluated the relationships of sleep duration and regularity on dietary intake of young preschool-aged children. The goal of this study was to evaluate whether short sleep duration and irregular sleep timing were associated with greater calorie, carbohydrate and fat consumption among young children with obesity from low-income families. Methods: Fifty-one ethnically diverse children aged 2 to 4 years were recruited from the Special Supplemental Nutrition Program for Women, Infants, and Children clinics in a southeast Texas county. Sleep behaviors were parent reported using the Child Sleep Assessment tool. Dietary intake data were obtained by 24-hour recall interviews (2 weekdays and 1 weekend day). Results: Short sleep duration (<11 hr) was highly prevalent among this cohort of preschool-aged children. Short sleep duration was associated with greater fat and decreased carbohydrate consumption. Children with greater variability in sleep duration and timing had greater energy intake from fat and protein sources. Conclusion: Allowing for the opportunity to educate parents on the importance of maintaining regular, adequate sleep and relationships between sleep and dietary intake may decrease the risk of childhood obesity in this high-risk pediatric population.

Benzodiazepine (BZD) use in community-dwelling older adults: Longitudinal associations with mobility, functioning, and pain

The aim of the study was to determine the prospective association between baseline BZD use and mobility, functioning, and pain among urban and rural African-American and non-Hispanic white community-dwelling older adults. From 1999 to 2001, a cohort of 1000 community-dwelling adults, aged ≥ 65 years, representing a random sample of Medicare beneficiaries, stratified by ethnicity, sex, and urban/rural residence were recruited. BZD use was assessed at an in-home visit. Every six months thereafter, study outcomes were assessed via telephone for 8.5-years. Mobility was assessed with the Life-Space Assessment (LSA). Functioning was quantified with level of difficulty in five basic activities of daily living (ADL: bathing, dressing, transferring, toileting, eating), and six instrumental activities of daily living (IADL: shopping, managing money, preparing meals, light and heavy housework, telephone use). Pain was measured by frequency per week and the magnitude of interference with daily tasks. All analytic models were adjusted for relevant covariates and mental health symptoms. After multivariable adjustment, baseline BZD use was significantly associated with greater difficulty with basic ADL (Estimate=0.39, 95% confidence interval (CI): 0.04-0.74), and more frequent pain (Estimate=0.41, 95%CI: 0.09-0.74) in the total sample and declines in mobility among rural residents (Estimate=-0.67, t(5,902)=-1.98, p=0.048), over 8.5 years. BZD use was prospectively associated with greater risk for basic ADL difficulties and frequent pain among African-American and non-Hispanic white community-dwelling older adults, and life-space mobility declines among rural-dwellers, independently of relevant covariates. These findings highlight the potential long-term negative impact of BZD use among community-dwelling older adults.