Project description:OBJECTIVE:Sleep duration is associated with obesity and cardiometabolic disease. It is unclear, though, how these relationship differs across age groups. METHODS:Data from 2007 to 2008 National Health and Nutrition Examination Survey (NHANES) were used, including respondents aged 16+ with complete data (N?=?5,607). Sleep duration and age were evaluated by self-report, and body mass index (BMI) was assessed objectively. Sleep duration was evaluated continuously and categorically [very short (?4 h), short (5-6 h), and long (?9 h) versus average (7-8 h)]. Age was also evaluated continuously and categorically [adolescent (16-17 years), young adult (18-29 years), early middle age (30-49 years), late middle age (50-64 years), and older adult (?65 years)]. RESULTS:There was a significant interaction with age for both continuous (Pinteraction ?=?0.014) and categorical (Pinteraction ?=?0.035) sleep duration. A pseudo-linear relationship was seen among the youngest respondents, with the highest BMI associated with the shortest sleepers and the lowest BMI associated with the longest sleepers. This relationship became U-shaped in middle-age, and less of a relationship was seen among the oldest respondents. CONCLUSIONS:These findings may provide insights for clinical recommendations and could help to guide mechanistic research regarding the sleep-obesity relationship.
Project description:Study objectivesMounting evidence indicates that sleep disturbance contributes to the increased risk for cardiometabolic diseases. Obesity and underweight are also closely linked to cardiometabolic risk. Thus, the objective of this study was to examine the association between sleep duration, quality, and body mass index (BMI) categories.MethodsUsing data from a cohort of 107,718 Korean individuals (63,421 men and 44,297 women), we conducted cross-sectional analysis with sex subgroup analysis. Sleep duration was classified into 3 groups-short (< 7 hours), normal (7-9 hours) and long sleep (> 9 hours)-and Pittsburgh Sleep Quality Index (PSQI) score was used to divide sleep quality into 2 groups-poor (PSQI > 5) and good sleep (PSQI ≤ 5). Compared to normal sleep and good sleep quality, adjusted odds ratios of short and long sleep and poor sleep for BMI categories were calculated. BMI categories included underweight (BMI < 18.5 kg/m2), overweight (BMI 23 to < 25 kg/m2), obesity (BMI 25 to < 30 kg/m2) and severe obesity (BMI ≥ 30 kg/m2).ResultsShort sleep duration had the dose-dependent relationship with obesity categories from overweight to severe obesity, and inverse relationship with underweight (adjusted odds ratios [95% confidence intervals] for underweight, overweight, obesity, and severe obesity versus normal weight; 0.88 [0.82-0.94], 1.15 [1.11-1.20], 1.31 [1.26-1.37], 1.70 [1.54-1.85]). Poor sleep quality was significantly associated with severe obesity in male subgroup (1.16 [1.05-1.27]) and with obesity (1.18 [1.10-1.25]) and severe obesity in female subgroup (1.66 [1.40-1.98]).ConclusionsShort sleep duration and poor sleep quality was more positively associated with obesity across BMI than underweight.
Project description:BackgroundElectrocardiogram (ECG) measured QRS duration has been shown to influence cardiovascular outcomes. However, there is paucity of data on whether ECG QRS duration is influenced by obesity and sex in large populations.MethodsAll ECGs performed by a pathology provider over a 2-year period were included. ECGs with confounding factors and those not in sinus rhythm were excluded from the primary analysis.ResultsOf the 76,220 who met the inclusion criteria, 41,685 (55%) were females. The median age of the study cohort was 61 years (interquartile [IQR] range 48-71 years). The median QRS duration was 86 ms (IQR 80-94 ms). The median BMI was 27.6 kg/m2 (IQR 24.2-31.8 kg/m2). When stratified according to the World Health Organization classification of BMI < 18.50 kg/m2, 18.50-24.99 kg/m2, 25.00-29.99 kg/m2, and ≥ 30.00 kg/m2, the median QRS durations were 82 ms (IQR 76-88 ms), 86 ms (IQR 80-92 ms), 88 ms (IQR 80-94 ms) and 88 ms (IQR 82-94 ms), respectively (p < 0.001 for linear trend). Median QRS duration for females was 84 ms (IQR 78-88 ms); for males, it was 92 ms (IQR 86-98 ms), p < 0.001. Compared to males, females had narrower QRS complexes at similar age and similar BMI. In multiple linear regression analysis, BMI correlated positively with QRS duration (standardized beta 0.095, p < 0.001) independent of age, sex, and heart rate.ConclusionsIn this large cohort there was a positive association between increasing BMI and QRS duration. Females had narrower QRS duration than males at similar age and similar BMI.
Project description:The clinical recognition of cardiometabolic disorders might be enhanced by anthropometry based on the sagittal abdominal diameter (SAD; also called "abdominal height") or waist circumference rather than on weight. Direct comparisons of body mass index (BMI, weight/height(2)) with SAD/height ratio (SADHtR) or waist circumference/height ratio (WHtR) have not previously been tested in nationally representative populations.Nonpregnant adults without diagnosed diabetes (ages 20-64 years; n = 3071) provided conventional anthropometry and supine SAD (by sliding-beam caliper) in the 2011-2012 US National Health and Nutrition Examination Survey. Population-weighted, logistic models estimated how strongly each anthropometric indicator was associated with 5 cardiometabolic disorders: Dysglycemia (glycated hemoglobin ?5.7%), HyperNonHDLc (non-high-density-lipoprotein [HDL] cholesterol ?4.14 mmol/L, or taking anticholesteremic medications), Hypertension (systolic blood pressure ?140 mm Hg or diastolic blood pressure ?90 mm Hg, or taking antihypertensive medications), HyperALT (alanine transaminase ?p75 [75th percentile, sex-specific]), and HyperGGT (gamma-glutamyltransferase ?p75 [sex-specific]).After scaling each indicator, adjusted odds ratios (aORs) tended to be highest for SADHtR and lowest for BMI when identifying each disorder except dysglycemia. When SADHtR entered models simultaneously with BMI, the aORs for BMI no longer directly identified any condition, whereas SADHtR identified persons with HyperNonHDLc by aOR 2.78 (95% confidence interval [CI], 1.71-4.51), Hypertension by aOR 2.51 (95% CI, 1.22-5.15), HyperALT by aOR 2.89 (95% CI, 1.56-5.37), and HyperGGT by aOR 5.43 (95% CI, 3.01-9.79). WHtR competed successfully against BMI with regard to Dysglycemia, HyperNonHDLc, and HyperGGT. c-Statistics of SADHtR and WHtR were higher than those of BMI (P <.001) for identifying HyperNonHDLc and HyperGGT.Among nonelderly adults, SADHtR or WHtR recognized cardiometabolic disorders better than did the BMI.
Project description:There is evidence across several species for genetic control of phenotypic variation of complex traits, such that the variance among phenotypes is genotype dependent. Understanding genetic control of variability is important in evolutionary biology, agricultural selection programmes and human medicine, yet for complex traits, no individual genetic variants associated with variance, as opposed to the mean, have been identified. Here we perform a meta-analysis of genome-wide association studies of phenotypic variation using ?170,000 samples on height and body mass index (BMI) in human populations. We report evidence that the single nucleotide polymorphism (SNP) rs7202116 at the FTO gene locus, which is known to be associated with obesity (as measured by mean BMI for each rs7202116 genotype), is also associated with phenotypic variability. We show that the results are not due to scale effects or other artefacts, and find no other experiment-wise significant evidence for effects on variability, either at loci other than FTO for BMI or at any locus for height. The difference in variance for BMI among individuals with opposite homozygous genotypes at the FTO locus is approximately 7%, corresponding to a difference of ?0.5?kilograms in the standard deviation of weight. Our results indicate that genetic variants can be discovered that are associated with variability, and that between-person variability in obesity can partly be explained by the genotype at the FTO locus. The results are consistent with reported FTO by environment interactions for BMI, possibly mediated by DNA methylation. Our BMI results for other SNPs and our height results for all SNPs suggest that most genetic variants, including those that influence mean height or mean BMI, are not associated with phenotypic variance, or that their effects on variability are too small to detect even with samples sizes greater than 100,000.
Project description:To evaluate associations between early-pregnancy body mass index (BMI) and active first stage labour duration, accounting for possible interaction with maternal age, we conducted a cohort study of women with spontaneous onset of labour allocated to Robson group 1. Quantile regression analysis was performed to estimate first stage labour duration between BMI categories in two maternal age subgroups (more and less than 30 years). Results show that obesity (BMI > 30) among younger women (< 30 years) increased the median labour duration of first stage by 30 min compared with normal weight women (BMI < 25), and time difference estimated at the 90th quantile was more than 1 h. Active first stage labour time differences between obese and normal weight women was modified by maternal age. In conclusion: (a) obesity is associated with longer duration of first stage of labour, and (b) maternal age is an effect modifier for this association. This novel finding of an effect modification between BMI and maternal age contributes to the body of evidence that supports a more individualized approach when describing labour duration.
Project description:This study explored the relationship between BMI trajectories and the duration of obesity in Thai children diagnosed with hypertension. Demographic and blood pressure data from 536 children (270 boys, 50.3%) from a school in Bangkok, Thailand were collected. Hypertension was defined as blood pressure above the cutoff values specified in the 2017 American Academy of Pediatrics guidelines on 3 occasions. Records of BMI over the previous 3 years were reviewed. The prevalence of hypertension was 2.61% (14/536). Complete data on BMI trajectories were available in 421 non-hypertensive and 12 hypertensive children. The increase in BMI z-score over the previous 3 years was significantly greater in the hypertensive group than the non-hypertensive group, 1.45 (95% CI 0.42 to 1.88) versus 0.09 (95% CI: -0.35, 0.65), P = .008. In conclusion, children with a confirmed diagnosis of hypertension had a greater increase in BMI over the past 3 years than non-hypertensive children.
Project description:BackgroundThe relationship between sleep duration and anthropometric indices are still unclear. This study aimed to explore the association between sleep duration and body mass index (BMI), percentage of body fat (PBF) and visceral fat area (VFA) among Chinese adults, further to explore gender difference in it.MethodsWe analyzed part of the baseline data of a cohort study among adult attendees at two health-screening centers in China. Sleep duration was self-reported and categorized into short (< 7 h/day), optimal (7-9 h/day) and long sleep (≥ 9 h/day). BMI, PBF and VFA were assessed by bioelectric impedance analysis. Demographic characteristics, chronic diseases and medication history, physical activity, smoking and alcohol drinking behaviors were measured by an investigator-administrated questionnaire.ResultsA total of 9059 adult participants (63.08% were females) were included in the analysis. The participants aged from 19 to 91 years with the mean age of 45.0 ± 14.6 years. Short sleep was independently associated with elevated odds of general obesity (defined using BMI) and visceral obesity (defined using VFA) among the total study population, and gender differences were observed in these associations. Among women, short sleep was associated with 62% increased odds of general obesity (OR = 1.62, 95% CI: 1.24-2.12) and 22% increased odds of visceral obesity (OR = 1.22, 95% CI: 1.02-1.45). Among men, long sleep duration was associated with 21% decreased odds of visceral obesity (OR = 0.79, 95% CI: 0.64-0.99). No association was observed between sleep duration and PBF in both sexes.ConclusionsSleep duration was associated with increased odds of general and visceral obesity, and this association differed between men and women. No association was observed between sleep duration and PBF among either males or females.
Project description:Both short and long durations of sleep are associated with higher mortality, but little is known about the interrelationship between sleep and other modifiable factors in relation to mortality. In the National Institutes of Health-AARP Diet and Health Study (1995-1996), we examined associations between sleep duration and total, cardiovascular disease (CVD), and cancer mortality among 239,896 US men and women aged 51-72 years who were free of cancer, CVD, and respiratory disease. We evaluated the influence of moderate-to-vigorous physical activity, television viewing, and body mass index (BMI; weight (kg)/height (m)(2)) on the sleep-mortality association and assessed their combined association with mortality. During an average of 14 years of follow-up, we identified 44,100 deaths. Compared with 7-8 hours of sleep per day, both shorter and longer sleep durations were associated with higher total and CVD mortality. We found a greater elevation in CVD mortality associated with shorter sleep among overweight and obese people, suggesting a synergistic interaction between sleep and BMI. People in the unhealthy categories of all 4 risk factors (sleep <7 hours/day, moderate-to-vigorous physical activity ?1 hour/week, television viewing ?3 hours/day, and BMI ?25) had significantly higher all-cause (relative risk (RR) = 1.42, 95% confidence interval (CI): 1.34, 1.52), CVD (RR = 1.90, 95% CI: 1.67, 2.17), and cancer (RR = 1.21, 95% CI: 1.09, 1.34) mortality. Short sleep duration may predict higher mortality, particularly CVD mortality, among overweight and obese people.
Project description:Research suggests that sleep duration and obesity are related, but the direction of this association remains uncertain. We applied autoregressive cross-lag models to evaluate the directionality of the relationship between sleep duration and BMI from adolescence through emerging and young adulthood, life stages where the risk for developing obesity are particularly high. Using data from the National Longitudinal Study of Adolescent to Adult Health (Add Health), we examined sex-stratified associations between sleep duration and BMI in this cohort from adolescence (ages 12-18, year 1996), to emerging adulthood (ages 18-24, 2001-2002), to young adulthood (ages 24-32, 2008), controlling for key confounders. For both males and females, higher BMI during an earlier developmental stage was associated with shorter sleep duration in the subsequent stage (both Bs?=?-0.02, ps?<?0.01). However, sleep duration at an earlier developmental stage was not associated with BMI at the subsequent stage. Findings suggest that researchers should be cautious when interpreting cross-sectional relationships between sleep and BMI, as higher BMI may precede shorter sleep during adolescence to young adulthood. Researchers may also wish to account for potential bi-directional associations when modeling sleep and BMI using longitudinal data.