Secondhand smoke exposure is longitudinally associated with shorter parent-reported sleep duration during childhood.

BACKGROUND: Secondhand smoke exposure has been cross-sectionally associated with worse sleep health outcomes in children and shorter sleep duration in adolescents. OBJECTIVES: We assessed longitudinal and cross-sectional associations between secondhand smoke (SHS) exposure and shorter sleep duration in children from the Fragile Families and Child Wellbeing Study, a longitudinal birth cohort. We additionally examined whether associations would persist after controlling for potential confounders. PARTICIPANTS: Mothers (n = 4898) were recruited using a stratified random sample of large United States cities and oversampling for nonmarital births. MEASUREMENTS: Mothers were asked about whether they smoked during pregnancy, whether their child spent time with someone who is smoking, and their child's weekday sleep duration. Sociodemographic factors, asthma diagnosis, and bedtime routines were assessed as potential confounders. Data collected at ages 3, 5, and 9 years were analyzed using multivariable regression models (N = 1912; 51.6% boys). RESULTS: SHS exposure at age 3 predicted 15.0 fewer minutes at age 5 (P = .001) and 12.3 fewer minutes at age 9 (P = .003). SHS exposure at age 9 was cross-sectionally associated with 14.4 fewer minutes of sleep duration at age 9 (P = .002). Findings persisted after controlling for potential confounders. CONCLUSION: These results provide associational support for the hypothesis that SHS exposure may have long-term consequences for childhood sleep duration. Future studies should investigate the relationship between SHS exposure and shorter sleep duration using objective measurements of serum cotinine and sleep actigraphy and by exploring potential mechanisms.

Examining the diagnostic validity of the Berlin Questionnaire in a low-income Black American sample.

STUDY OBJECTIVES: Black individuals and individuals of low socioeconomic status are at increased risk for obstructive sleep apnea (OSA). The Berlin Questionnaire is one of the most widely used screening tools for OSA; however, there is limited research on its diagnostic accuracy in low-income Black populations. METHODS: This study analyzed data from an ongoing study taking place among a cohort from 2 predominantly Black neighborhoods in Pittsburgh, Pennsylvania (96.3% Black, 79.6% female). The sample included 269 individuals without a prior diagnosis of OSA who completed the Berlin Questionnaire and also participated in a home sleep apnea test. An apnea-hypopnea index ≥ 15 events/h was used to identify individuals with moderate or severe OSA. RESULTS: 19.3% of individuals met criteria for moderate to severe OSA based on home sleep apnea test, while 31.2% of participants screened as high risk for OSA based on the overall Berlin index. Using apnea-hypopnea index ≥ 15 events/h as the reference standard, the Berlin Questionnaire had a sensitivity of 46.2%, specificity of 72.4%, positive predictive value of 28.6%, and negative predictive value of 84.9% among this sample. Analyses stratified by sex suggested that the Berlin Questionnaire had better diagnostic validity in women than men. CONCLUSIONS: The Berlin Questionnaire has lower sensitivity and positive predictive value in our sample than those observed in general population samples. The measure performed better among women, though a higher proportion of men fell into the moderate or severe OSA range based on the home sleep apnea test. Given the significant downstream consequences of OSA, utilizing screening tools that better detect OSA in Black communities is key. CITATION: Holliday SB, Haas A, Dong L, et al. Examining the diagnostic validity of the Berlin Questionnaire in a low-income Black American sample. J Clin Sleep Med. 2021;17(10):1987-1994.

Risk of metabolic syndrome and metabolic phenotypes in relation to biomarker-calibrated estimates of energy and protein intakes: an investigation from the Women's Health Initiative.

BACKGROUND: Metabolic syndrome (MetS) is associated with increased mortality independent of BMI, resulting in discordant metabolic phenotypes, such as metabolically healthy obese and metabolically unhealthy normal-weight individuals. Studies investigating dietary intake in MetS have reported mixed results, due in part to the limitations of self-reported measures. OBJECTIVES: To investigate the role of biomarker-calibrated estimates of energy and protein in MetS and metabolic phenotypes. METHODS: Postmenopausal participants from the Women's Health Initiative (WHI) study who were free of MetS at baseline, had available data from FFQs at baseline, and had components of MetS at Year 3 (n = 3963) were included. Dietary energy and protein intakes were estimated using biomarker calibration methods. MetS was defined as 3 or more of the following: elevated serum triglycerides (≥150 mg/dL), low HDL cholesterol (<50 mg/dL), hypertension [systolic blood pressure (BP) ≥130 or diastolic BP ≥85 mmHg], elevated serum glucose (>100 mg/dL), and abdominal adiposity (waist circumference > 89 cm). Models were adjusted for age, WHI study component, race/ethnicity, education, income, smoking, recreational physical activity, disease history, and parity. RESULTS: For every 10% increment in total calibrated energy intake, women were at a 1.37-fold elevated risk of MetS (95% CI, 1.15-1.63); a 10% increment in calibrated total protein intake was associated with a 1.21-fold elevated risk of MetS (95% CI, 1.00-1.47). Specifically, animal protein intake was associated with MetS (OR, 1.08; 95% CI, 1.02-1.14), whereas vegetable protein intake was not (OR, 0.99; 95% CI, 0.95-1.03). No differences were seen when examining metabolic phenotypes. CONCLUSIONS: We found that higher calibrated total energy, total protein, and total animal protein intakes were strongly associated with MetS. If replicated in clinical trials, these results will have implications for the promotion of energy and animal protein restrictions for the reduction of MetS risks.

Sleep Characteristics and Risk of Ovarian Cancer Among Postmenopausal Women.

Several studies have assessed the relationship between sleep duration and ovarian cancer risk, but the results are conflicting. Importantly, no studies addressed the relationship between sleep disturbance or sleep quality and ovarian cancer incidence. Moreover, few studies have examined the relationships between sleep measures and subtypes of ovarian cancer. This study included 109,024 postmenopausal women ages 50-79 from the Women's Health Initiative during 1993-1998 and followed through 2018. The Cox proportional hazards model was used to estimate adjusted HRs for the associations between sleep habits and the incidence of ovarian cancer and its subtypes. No association was observed between sleep duration, sleep quality, sleep disturbance, or insomnia and risk of overall ovarian cancer, serous/nonserous, or type I/type II ovarian cancer subtype. However, compared with women with average sleep quality, women with restful or very restful sleep quality had a significantly lower risk of invasive serous subtype [HR: 0.73, 95% confidence interval (CI): 0.60-0.90] while insomnia was associated with a higher risk of invasive serous subtype (HR: 1.36, 95% CI: 1.12-1.66). Associations with insomnia differed significantly by serous and nonserous subtypes, and type I and type II subtypes (P heterogeneity = 0.001 and P heterogeneity <0.001, respectively). This study provides no evidence on association between sleep habits and overall ovarian cancer risk among postmenopausal women. However, restful or very restful sleep quality was associated with a lower risk of invasive serous ovarian cancer, and insomnia was associated with a higher risk of invasive serous ovarian cancer. Associations with insomnia differed by subtypes. PREVENTION RELEVANCE: This study shows no association between sleep duration, sleep quality, or insomnia with the risk of overall ovarian cancer among postmenopausal women. However, restful sleep quality was associated with a lower risk of invasive serous ovarian cancer, and insomnia was associated with a higher risk of invasive serous ovarian cancer.

Smoke at night and sleep worse? The associations between cigarette smoking with insomnia severity and sleep duration.

OBJECTIVE: Insomnia is a clinically verified nicotine withdrawal symptom. As nicotine is a stimulant, it is plausible that smoking at night could disturb sleep more than smoking at earlier times of the day, but this remains empirically unclear. This study examined smoking status and its associations with insomnia severity and sleep duration while considering the potential role of smoking time. METHODS: Data were derived from the Sleep and Healthy Activity Diet Environment and Socialization study, a community-based study of 1007 adults (nnonsmokers = 818; nsmokers = 189) aged 22-60 from the Philadelphia area. Smoking status and time of smoking were self-reported. Insomnia was assessed with the Insomnia Severity Index and categorized as none, mild, and moderate-to-severe. Sleep duration was assessed with one item from the National Health and Nutrition Examination Survey and categorized as very short, short, normal, and long. Ordinal and multinomial logistic regressions were used to determine the association of smoking status including smoking time with insomnia severity and sleep duration controlling for sociodemographic covariates. RESULTS: Compared to nonsmoking, smoking was associated with experiencing increased insomnia (odds ratio = 2.5, 95% confidence interval [CI] 1.9, 3.4, P < .001) as well as very short (relative risk ratio = 1.9, 95% CI 1.1, 3.3) and short (relative risk ratio = 1.5, 95% CI 1.0, 2.3) sleep (vs normal sleep duration). Night-time smoking was significantly associated with greater insomnia and shorter sleep duration. CONCLUSIONS: Findings provide evidence that smoking is associated with increased insomnia severity and shorter sleep duration, particularly nightly smoking. Sleep health should be considered in smoking cessation efforts.

Prevalence and correlates of obstructive sleep apnea in urban-dwelling, low-income, predominantly African-American women.

STUDY OBJECTIVES: The current study examined the prevalence and correlates of obstructive sleep apnea in a sample of low-income, predominantly African-American women using two waves of data. METHODS: Participants were adults from two urban neighborhoods who enrolled in the PHRESH Zzz Study (N = 828; Pittsburgh Hill/Homewood Research on Neighborhoods, Sleep, and Health). A subsample who reported never receiving OSA diagnosis completed home sleep apnea testing in 2016 (n = 269, mean age 55.0 years, 79.6% female) and again in 2018 (n = 135). Correlates of OSA tested included demographic and anthropometric variables, health behavior/conditions, psychological distress and general health, smoking status, actigraphy-measured sleep, and neighborhood factors measured at baseline. RESULTS: 18.0% of all 2016 participants reported receiving physician diagnoses of OSA. Among those who completed in-home assessment, 19.3% had AHI ≥15 and 33.8% had AHI ≥5 plus one or more sleep symptoms. Estimates of the prevalence of OSA in all 2016 participants were 33.8%-45.7% based on physician diagnoses and AHI results, depending on the criteria used. Age, gender, BMI, blood pressure, habitual snoring, neighborhood walkability, actigraphy-measured sleep characteristics, and smoking were concurrently associated with OSA in 2016. Changes in AHI categories from 2016 to 2018 were documented. CONCLUSIONS: Low-income African Americans, including women, are a high-risk group for OSA, but remain under-diagnosed and under-treated. The current findings show a high prevalence of OSA in African-American women and are among the first to demonstrate that both individual and neighborhood factors are implicated in OSA prevalence.

Associations of Coffee and Tea Consumption With Survival to Age 90 Years Among Older Women.

BACKGROUND: Coffee and tea are two of the most widely consumed beverages worldwide and have been associated with reduced risk of mortality in some studies. However, it is unknown whether consumption of these beverages is associated with survival to an advanced age. OBJECTIVE: To examine associations of coffee and tea consumption with survival to age 90 years. DESIGN: Prospective cohort study among participants from the Women's Health Initiative, recruited during 1993 to 1998 and followed up until March 31, 2018. SETTING: The setting included 40 US clinical centers. PARTICIPANTS: A racially and ethnically diverse cohort of 27,480 older women, aged 65 to 81 years at baseline. MEASUREMENTS: Women were classified as having either survived to age 90 years or died before this age. Consumption of caffeinated and decaffeinated coffee and caffeinated tea was assessed at baseline and categorized as 0, 1, 2 to 3, or 4 or more cups/day. Associations of coffee and tea consumption with survival to age 90 years were examined using logistic regression models adjusted for sociodemographic characteristics, lifestyle behaviors, dietary quality, and chronic disease history. RESULTS: A total of 14,659 (53.3%) women survived to age 90 years during follow-up. Caffeinated coffee, decaffeinated coffee, or caffeinated tea consumption was not significantly associated with survival to age 90 years after adjusting for confounders. Findings did not significantly vary by smoking, body mass index, or race/ethnicity. CONCLUSION: No amount of coffee or tea consumption was associated with late-age survival among older women. These findings may be reassuring to older women who consume coffee and tea as part of their daily diets but do not support drinking these beverages to achieve longevity.

Short Sleep Is Associated With Low Bone Mineral Density and Osteoporosis in the Women's Health Initiative.

Short sleep duration, recognized as a public health epidemic, is associated with adverse health conditions, yet little is known about the association between sleep and bone health. We tested the associations of usual sleep behavior and bone mineral density (BMD) and osteoporosis. In a sample of 11,084 postmenopausal women from the Women's Health Initiative (WHI; mean age 63.3 years, SD = 7.4), we performed a cross-sectional study of the association of self-reported usual hours of sleep and sleep quality (WHI Insomnia Rating Score) with whole body, total hip, femoral neck, and spine BMD using linear regression models. We also studied the association of sleep duration and quality with dual-energy X-ray absorptiometry (DXA)-defined low bone mass (T-score < -2.5 to <-1) and osteoporosis (T-score ≤ -2.5) using multinomial regression models. We adjusted for age, DXA machine, race, menopausal symptoms, education, smoking, physical activity, body mass index, alcohol use, physical function, and sleep medication use. In adjusted linear regression models, women who reported sleeping 5 hours or less per night had on average 0.012 to 0.018 g/cm2 significantly lower BMD at all four sites compared with women who reported sleeping 7 hours per night (reference). In adjusted multinomial models, women reporting 5 hours or less per night had higher odds of low bone mass and osteoporosis of the hip (odds ratio [OR] = 1.22; 95% confidence interval [CI] 1.03-1.45, and 1.63; 1.15-2.31, respectively). We observed a similar pattern for spine BMD, where women with 5 hours or less per night had higher odds of osteoporosis (adjusted OR = 1.28; 95% CI 1.02-1.60). Associations of sleep quality and DXA BMD failed to reach statistical significance. Short sleep duration was associated with lower BMD and higher risk of osteoporosis. Longitudinal studies are needed to confirm the cross-sectional effects of sleep duration on bone health and explore associated mechanisms. © 2019 American Society for Bone and Mineral Research.

Contributions of the Women's Health Initiative to understanding associations between sleep duration, insomnia symptoms, and sleep-disordered breathing across a range of health outcomes in postmenopausal women.

The Women's Health Initiative (WHI), a longitudinal study of more than 161,000 postmenopausal women across the United States, provides an opportunity to investigate the link between sleep health and healthy aging. The purpose of this paper was to systematically review all published WHI articles examining sleep as a predictor of health outcomes and health behaviors/quality of life outcomes. A strength of the WHI is that for most participants, sleep measures were completed before a major health diagnosis, with a significant portion of participants also providing sleep measures after diagnosis. Twenty-three WHI articles were identified and examined for this review. The combination of sleep duration and insomnia symptoms was the most commonly investigated sleep measure. The results indicated that both short (≤6 hours) and long (≥9 hours) sleep duration were associated with a higher risk of cardiovascular disease, colorectal cancer, mortality, cognitive decline, and poor diet. Insomnia symptoms, frequent snoring, and risk of sleep-disordered breathing (SDB) were also associated with increased risk for ischemic stroke and cardiovascular disease. However, many significant results were attenuated after multivariable adjustment. Limitations of these WHI examinations include the use of different categories for sleep measures across studies and a lack of examination by race/ethnicity. Owing to the longitudinal study design, large sample size, and long-term follow-up for health outcomes, the WHI serves as a rich resource for examining associations between sleep characteristics, demographics, and health in postmenopausal women.

Sequencing Analysis at 8p23 Identifies Multiple Rare Variants in DLC1 Associated with Sleep-Related Oxyhemoglobin Saturation Level.

Average arterial oxyhemoglobin saturation during sleep (AvSpO2S) is a clinically relevant measure of physiological stress associated with sleep-disordered breathing, and this measure predicts incident cardiovascular disease and mortality. Using high-depth whole-genome sequencing data from the National Heart, Lung, and Blood Institute (NHLBI) Trans-Omics for Precision Medicine (TOPMed) project and focusing on genes with linkage evidence on chromosome 8p23,1,2 we observed that six coding and 51 noncoding variants in a gene that encodes the GTPase-activating protein (DLC1) are significantly associated with AvSpO2S and replicated in independent subjects. The combined DLC1 association evidence of discovery and replication cohorts reaches genome-wide significance in European Americans (p = 7.9 × 10-7). A risk score for these variants, built on an independent dataset, explains 0.97% of the AvSpO2S variation and contributes to the linkage evidence. The 51 noncoding variants are enriched in regulatory features in a human lung fibroblast cell line and contribute to DLC1 expression variation. Mendelian randomization analysis using these variants indicates a significant causal effect of DLC1 expression in fibroblasts on AvSpO2S. Multiple sources of information, including genetic variants, gene expression, and methylation, consistently suggest that DLC1 is a gene associated with AvSpO2S.

Ageratina adenophora invasions are associated with microbially mediated differences in biogeochemical cycles.

Invasive plant species may alter soil nutrient availability to facilitate their growth and competitiveness. However, the roles and functional mechanisms of plant-associated microbes that mediate these soil biogeochemical cycles remain elusive. Here, we studied how soil microorganisms and their functional processes differed between soils invaded by Ageratina adenophora and adjacent non-invaded soils in a region of China with heavy invasion. Our results indicated that soil nitrogen contents were over 4.32 mg/kg higher (p < 0.05) in both rhizosphere soils and bulk soils dominated by A. adenophora as compared with those in soils dominated by non-invaded plants. Concurrently, soil microbial-mediated functional processes, i.e. nitrogen fixation rate, nitrification rate and ammonification rate, were also significantly (p < 0.05) higher in either rhizosphere soils or bulk soils of invasive A. adenophora. Using a functional gene microarray, we found higher relative abundances of soil microbial genes involved in N cycling processes in A. adenophora soils, e.g. nifH, required for nitrogen fixation, which significantly correlated with ammonia contents (r = 0.35 in bulk soils, r = 0.37 in rhizosphere soils, p < 0.05) and the nitrogen fixation rate (r = 0.44, p < 0.05). We also found that the relative abundances of labile carbon decomposition genes were higher in invasive A. adenophora soils, implying a potential higher availability of carbon. These results suggest that the soil surrounding the invasive plant A. adenophora is a self-reinforcing environment. The plant litter and rhizosphere environment of the invasive may influence soil microbial communities, promoting self-supporting soil processes. Alternatively, the regions invaded by A. adenophora may have already had properties that facilitated these beneficial microbial community traits, allowing easier invasion by the exotics. Both scenarios offer important insights for the mitigation of plant invasion and provide an ecosystem-level understanding of the invasive mechanisms utilized by alien plants.

Higher amounts of sedentary time are associated with short sleep duration and poor sleep quality in postmenopausal women.

STUDY OBJECTIVES: To evaluate the associations between sedentary time, total (total-PA), light (light-PA), moderate (MOD-PA), and vigorous (VIG-PA) physical activity with indices of sleep in postmenopausal women. METHODS: Baseline self-reported data from the Women's Health Initiative Observational Study (n = 75 074) were used in this cross-sectional analysis. Total-PA, light-PA, MOD-PA, and VIG-PA were categorized by metabolic equivalents of the activity (MET-hour [hr]/week [wk]) and were estimated using validated questionnaires. Sedentary time was categorized by hr/day and was estimated via questionnaire. Logistic regression was used to examine the associations between these variables and short sleep (≤6 hr/night), long sleep (≥10 hr/night), poor sleep quality, and insomnia symptoms after adjustment for age, race, socioeconomic status, body mass index, health status, depressive symptoms, smoking status, alcohol use, hormone therapy, and comorbidities. RESULTS: Higher sedentary time (>11 hr/day) was associated with higher odds of short sleep (odds ratio [OR] = 1.80, 95% confidence interval [CI]: 1.72-1.88), poor sleep quality (OR = 1.85, 95% CI: 1.74-1.97), and insomnia symptoms (OR = 1.56, 95% CI: 1.49-1.64). Light-PA (>0 MET-hr/wk) was associated with lower odds of short sleep (OR = 0.96, 95% CI: 0.92-1.00), and higher amounts of total-PA (OR = 0.90, 95% CI: 0.84-0.97), light-PA (OR = 0.94, 95% CI: 0.89-1.00), and MOD-PA (OR = 0.91, 95% CI: 0.86-0.97) were associated with lower odds of poor sleep quality. CONCLUSIONS: Our findings suggest that higher levels of light and moderate intensity physical activity are associated with better sleep quality, whereas higher amounts of sedentary time are associated with short sleep and lower quality sleep. Future studies should investigate the directionality of these associations and potential causal pathways.

Habitual sleep quality, plasma metabolites and risk of coronary heart disease in post-menopausal women.

BACKGROUND: Epidemiologic studies suggest a strong link between poor habitual sleep quality and increased cardiovascular disease risk. However, the underlying mechanisms are not entirely clear. Metabolomic profiling may elucidate systemic differences associated with sleep quality that influence cardiometabolic health. METHODS: We explored cross-sectional associations between sleep quality and plasma metabolites in a nested case-control study of coronary heart disease (CHD) in the Women's Health Initiative (WHI; n = 1956) and attempted to replicate the results in an independent sample from the Nurses' Health Study II (NHSII; n = 209). A sleep-quality score (SQS) was derived from self-reported sleep problems asked in both populations. Plasma metabolomics were assayed using LC-MS with 347 known metabolites. General linear regression was used to identify individual metabolites associated with continuous SQS (false-discovery rate <0.05). Using least absolute shrinkage and selection operator (LASSO) algorithms, a metabolite score was created from replicated metabolites and evaluated with CHD risk in the WHI. RESULTS: After adjusting for age, race/ethnicity, body mass index (BMI) and smoking, we identified 69 metabolites associated with SQS in the WHI (59 were lipids). Of these, 16 were replicated in NHSII (15 were lipids), including 6 triglycerides (TAGs), 4 phosphatidylethanolamines (PEs), 3 phosphatidylcholines (PCs), 1 diglyceride (DAG), 1 lysophosphatidylcholine and N6-acetyl-L-lysine (a product of histone acetylation). These metabolites were consistently higher among women with poorer sleep quality. The LASSO selection resulted in a nine-metabolite score (TAGs 45: 1, 48: 1, 50: 4; DAG 32: 1; PEs 36: 4, 38: 5; PCs 30: 1, 40: 6; N6-acetyl-L-lysine), which was positively associated with CHD risk (odds ratio per SD increase in the score: 1.16; 95% confidence interval: 1.05, 1.28; p = 0.0003) in the WHI after adjustment for matching factors and conventional CHD risk factors. CONCLUSIONS: Differences in lipid metabolites may be an important pathogenic pathway linking poor habitual sleep quality and CHD risk.

Change in longitudinal trends in sleep quality and duration following breast cancer diagnosis: results from the Women's Health Initiative.

Breast cancer survivors frequently report sleep problems, but little research has studied sleep patterns longitudinally. We examined trends in sleep quality and duration up to 15 years before and 20 years after a diagnosis of breast cancer, over time among postmenopausal women participating in the Women's Health Initiative (WHI). We included 12,098 participants who developed invasive breast cancer after study enrollment. A linear mixed-effects model was used to determine whether the time trend in sleep quality, as measured by the WHI Insomnia Rating Scale (WHIIRS), a measure of perceived insomnia symptoms from the past 4 weeks, changed following a cancer diagnosis. To examine sleep duration, we fit a logistic regression model with random effects for both short (<6 h) and long (≥9 h) sleep. In addition, we studied the association between depressive symptoms and changes in WHIIRS and sleep duration. There was a significantly slower increase in the trend of WHIIRS after diagnosis (ß = 0.06; p = 0.03), but there were non-significant increases in the trend of the probability of short or long sleep after diagnosis. The probability of depressive symptoms significantly decreased, though the decrease was more pronounced after diagnosis (p < 0.01). Trends in WHIIRS worsened at a relatively slower rate following diagnosis and lower depression rates may explain the slower worsening in WHIIRS. Our findings suggest that over a long period of time, breast cancer diagnosis does not adversely affect sleep quality and duration in postmenopausal women compared to sleep pre-diagnosis, yet both sleep quality and duration continue to worsen over time.

The association of sleep duration and quality with all-cause and cause-specific mortality in the Women's Health Initiative.

BACKGROUND/OBJECTIVE: Many studies have shown a U-shaped association of sleep duration with mortality; however, this association is difficult to interpret owing to possible reverse causation, residual confounding, and measurement issues. We used data from the Women's Health Initiative to examine the associations of sleep duration, insomnia, and use of sleep aids with death from cardiovascular disease (CVD), cancer, "other" causes, and all causes combined. METHODS: Cox proportional hazards models were used in the analysis of baseline data and in time-dependent analyses of repeated measures to estimate associations of sleep-related factors with mortality. Among 158,203 women with information regarding sleep, 30,400 total deaths, 8857 CVD deaths, 9284 cancer deaths, and 11,928 other deaths were ascertained over a median of 17.8 years. RESULTS: In both baseline and time-dependent analyses, both short (≤5 h) and long sleep (≥9 h) durations were associated with increased risk of total, CVD, and "other" deaths, but not with cancer deaths. Insomnia showed no association with mortality, whereas use of sleep medications was associated with an increased mortality risk. CONCLUSIONS: While our findings showed a small but robust association of sleep duration with mortality in postmenopausal women, studies including objective measurements of sleep quality and efficiency are needed to clarify these associations.

Sleep Duration and Risk of Liver Cancer in Postmenopausal Women: The Women's Health Initiative Study.

BACKGROUND: Sleep duration has been associated with nonalcoholic fatty liver disease, but its association with liver cancer remains unknown. MATERIAL AND METHODS: In the prospective Women's Health Initiative Study, 139,368 postmenopausal women reported sleep habits at baseline (1993-1998). We ascertained 175 incident liver cancer cases during an average 13.8 years of follow-up through August 2014. We used multivariable Cox proportional hazard regression models to estimate a hazard ratio (HR) and its 95% confidence interval (95% CI) for risk of liver cancer in association with nocturnal sleep duration. RESULTS: Compared to women reporting 6-8 hours of sleep, the HR for liver cancer was 1.94 (95% CI 1.07-3.53) for women reporting ≥9 hours of sleep. Among the obese women, the HR associated with ≥9 hours of sleep was 3.18 (95% CI 1.84-8.60). The HR was 0.93 (95% CI 0.34-2.53) among nonobese women (p value for interaction = 0.18). Short sleep duration (≤5 hours) was not associated with liver cancer risk. CONCLUSION: Long sleep duration was associated with a moderate increase in liver cancer risk in obese postmenopausal women in the United States. Larger study is needed to confirm our observation on effect modification by adiposity status.

Sleep quality, duration, and breast cancer aggressiveness.

PURPOSE: Epidemiological studies suggest that short sleep duration and poor sleep quality may increase breast cancer risk. However, whether sleep is associated with breast tumor aggressiveness characteristics has largely been unexplored. METHODS: The study included 4171 non-Hispanic whites (NHW) and 235 African Americans (AA) diagnosed with incident, primary, invasive breast cancer in the Women's Health Initiative (WHI) Observational Study (1994-2013). We used logistic regression to examine the association of baseline sleep (sleep duration, sleep quality, WHI Insomnia Rating Scale) with tumor grade, stage, hormone receptor status, HER2 status. RESULTS: In NHW, women who reported 6 h of sleep/night were more likely to have tumors classified as regional/distant stage at diagnosis compared to women who slept 7-8 h/night (adjusted odds ratio (OR): 1.25, 95% confidence interval (CI): 1.05-1.48). AA women who reported their typical night's sleep as 'average quality' or 'restless or very restless sleep' were more likely to be diagnosed with triple-negative tumors than those who reported 'sound or restful' sleep (adjusted ORs: 2.91 (1.11, 7.63) and 3.74 (1.10, 12.77), respectively). CONCLUSIONS: Our findings provide indications that aspects of sleep (sleep duration and quality), partially modifiable health behaviors, may be associated with development of aggressive tumor characteristics in postmenopausal women. The role of these sleep attributes may differ for NHW and AA women; however, further study in robust, racial diverse samples is needed. This study provides evidence that facets of sleep behavior are associated with the development of aggressive tumor features and these associations differ by race.

Disruption of gene pqqA or pqqB reduces plant growth promotion activity and biocontrol of crown gall disease by Rahnella aquatilis HX2.

Rahnella aquatilis strain HX2 has the ability to promote maize growth and suppress sunflower crown gall disease caused by Agrobacterium vitis, A. tumefaciens, and A. rhizogenes. Pyrroloquinoline quinone (PQQ), a cofactor of aldose and alcohol dehydrogenases, is required for the synthesis of an antibacterial substance, gluconic acid, by HX2. Mutants of HX2 unable to produce PQQ were obtained by in-frame deletion of either the pqqA or pqqB gene. In this study, we report the independent functions of pqqA and pqqB genes in relation to PQQ synthesis. Interestingly, both the pqqA and pqqB mutants of R. aquatilis eliminated the ability of strain HX2 to produce antibacterial substance, which in turn, reduced the effectiveness of the strain for biological control of sunflower crown gall disease. The mutation also resulted in decreased mineral phosphate solubilization by HX2, which reduced the efficacy of this strain as a biological fertilizer. These functions were restored by complementation with the wild-type pqq gene cluster. Additionally, the phenotypes of HX2 derivatives, including colony morphology, growth dynamic, and pH change of culture medium were impacted to different extents. Our findings suggested that pqqA and pqqB genes individually play important functions in PQQ biosynthesis and are required for antibacterial activity and phosphorous solubilization. These traits are essential for R. aquatilis efficacy as a biological control and plant growth promoting strain. This study enhances our fundamental understanding of the biosynthesis of an environmentally significant cofactor produced by a promising biocontrol and biological fertilizer strain.

Association between sleep and breast cancer incidence among postmenopausal women in the Women's Health Initiative.

STUDY OBJECTIVES: To determine whether the duration of sleep, sleep quality, insomnia, or sleep disturbance was associated with incident breast cancer in the Women's Health Initiative (WHI). DESIGN: Prospective cohort study. SETTING: Women enrolled in one of the Clinical Trial (CT) arms or the Observational Study (OS) from the WHI conducted in the United States. PARTICIPANTS: This study included 110,011 women age 50 to 79 years with no history of cancer. MEASUREMENTS AND RESULTS: Typical sleep duration, sleep quality, and other self-reported sleep measures over the past 4 weeks were assessed during the screening visits for both the CT and OS participants. The presence of insomnia and level of sleep disturbance was calculated from an index of the WHI Insomnia Rating Scale. The outcome for this study was primary, invasive breast cancer. A total of 5,149 incident cases of breast cancer were identified in this study. No statistically significant associations were found between sleep duration, sleep quality, insomnia, or level of sleep disturbance with the risk of breast cancer after multivariable adjustment. A positive trend was observed for increasing sleeping duration with the risk of estrogen receptor positive breast cancer, but the association estimates for each sleep duration category were weak and nonsignificant. CONCLUSIONS: This study does not provide strong support for an association between self-reported sleep duration, sleep quality, insomnia, or sleep disturbance with the risk of breast cancer.

Association between breast cancer and allostatic load by race: National Health and Nutrition Examination Survey 1999-2008.

BACKGROUND: Breast cancer and its treatment introduce numerous physiologic, psychological, social, and economic stressors to a woman with the diagnosis. Allostatic load, a composite score of biomarkers representing physiologic dysregulation, may serve as a measure of the biological burden of breast cancer. This study investigates the association between breast cancer and allostatic load scores by comparing allostatic load scores in those with a history of breast cancer to those without, stratified by race. METHODS: Black and white women aged 35 to 85 were analyzed using the data from NHANES 1999-2008 (n = 4875 women, of which 188 women had a history of breast cancer). Stratified by race, we ran multivariate analyses with history of breast cancer as a predictor for elevated allostatic load while adjusting for other potentially confounding variables. RESULTS: Although a history of breast cancer was not associated with elevated allostatic load in white women, it was significantly associated with elevated allostatic load in black women after adjusting for age, income, education, insurance type, smoking status, alcohol intake, and physical activity [Odds Ratio (OR) 2.08 (95%CI 1.02, 4.22)]. Furthermore, an interaction between black and having a history of breast cancer was found to be significant in predicting elevated allostatic load scores after adjusting for demographic, behavioral, and comorbidity characteristics. CONCLUSIONS: These results suggest that the biological toll of breast cancer may be greater in black women than white women.