Sleep quality and body mass index: a co-twin study

Problematic technology use and sleep quality in young adulthood: novel insights from a nationally representative twin study

STUDY OBJECTIVES

Digital technology use is associated with poor sleep quality in adolescence and young adulthood although research findings have been mixed. No studies have addressed the association between the two using a genetically informative twin design which could extend our understanding of the etiology of this relationship. This study aimed to test: (1) the association between adolescents' perceived problematic use of digital technology and poor sleep quality, (2) whether the association between problematic use of technology and poor sleep quality remains after controlling for familial factors, and (3) genetic and environmental influences on the association between problematic use of technology and poor sleep quality.

METHODS

Participants were 2232 study members (18-year-old twins) of the Environmental Risk (E-Risk) Longitudinal Twin Study. The sample was 48.9% male, 90% white, and 55.6% monozygotic. We conducted regression and twin difference analyses and fitted twin models.

RESULTS

Twin differences for problematic use of technology were associated with differences for poor sleep quality in the whole sample (p < 0.001; B = 0.15) and also when we limited the analyses to identical twins only (p < 0.001; B = 0.21). We observed a substantial genetic correlation between problematic use of technology and sleep quality (rA = 0.31), whereas the environmental correlation was lower (rE = 0.16).

CONCLUSIONS

Adolescent reported problematic use of digital technology is associated with poor sleep quality-even after controlling for familial factors including genetic confounds. Our results suggest that the association between adolescents' sleep and problematic digital technology use is not accounted for by shared genetic liability or familial factors but could reflect a causal association. This robust association needs to be examined in future research designed to test causal associations.

Behaviour genetics and sleep: A narrative review of the last decade of quantitative and molecular genetic research in humans

During the last decade quantitative and molecular genetic research on sleep has increased considerably. New behavioural genetics techniques have marked a new era for sleep research. This paper provides a summary of the most important findings from the last ten years, on the genetic and environmental influences on sleep and sleep disorders and their associations with health-related variables (including anxiety and depression) in humans. In this review we present a brief summary of the main methods in behaviour genetic research (such as twin and genome-wide association studies). We then discuss key research findings on: genetic and environmental influences on normal sleep and sleep disorders, as well as on the association between sleep and health variables (highlighting a substantial role for genes in individual differences in sleep and their associations with other variables). We end by discussing future lines of enquiry and drawing conclusions, including those focused on problems and misconceptions associated with research of this type. In this last decade our knowledge about genetic and environmental influences on sleep and its disorders has expanded. Both, twin and genome-wide association studies show that sleep and sleep disorders are substantially influenced by genetic factors and for the very first time multiple specific genetic variants have been associated with sleep traits and disorders.

Temporal changes in self-reported sleep quality, sleep duration and sleep medication use in relation to temporal changes in quality of life and work ability over a 1-year period among Finnish municipal employees

In this prospective follow-up study, we aimed to examine whether changes in self-reported sleep quality, sleep duration, and sleep medication use are temporally associated with changes in quality of life and work ability in municipal employees when several confounding factors are considered. The study was conducted in Finland among 637 municipal employees (88% women, mean [SD] age 48 [10] years) in 2014 and 2015. Information about the participants was collected by self-administered questionnaire and from medical history. Predicting variables were changes in self-reported sleep quality, sleep duration, and sleep medication use. Outcome variables were changes in the EUROHIS-QOL eight-item index and the Work Ability Score. Improved or unchanged sleep quality compared to worse sleep quality were associated with a preferable change in quality of life (both p < 0.001). No change in sleep duration compared to a decrease and no change in sleep medication use compared to increased use were also associated with favourable changes in quality of life. Increased use of sleep medication was associated with a decline in work ability, and the change in Work Ability Score also differed significantly between improved and worsened sleep quality. In this study, changes in sleep were widely associated with changes in quality of life and work ability of municipal employees. Programmes aiming for better sleep health would probably be beneficial both from a health-oriented and an economical point of view. Special attention should be paid to employees with a need for sleep medication.

Sleep Quality, Insomnia, Anxiety, Fatigue, Stress, Memory and Active Coping during the COVID-19 Pandemic

Background: The current study aimed to evaluate the impact of the coronavirus (COVID-19) pandemic on sleep quality, insomnia, anxiety, stress, fatigue and active coping in the United States. Methods: This was a cross-sectional study using a publicly available database taken from the Boston College COVID-19 Sleep and Well-Being Dataset. We have selected the most recent data that included information about sleep quality and other measures, including insomnia, anxiety, stress, fatigue and coping, collected between 22 February−8 March 2021. Results: A total of 476 subjects were included in the analysis. The mean (SD) age of the study population was 38.8 (17.8) years, and there were more females (85%) than males. The population had a mean (SD) score of the Pittsburgh Sleep Quality Index (PSQI) of 6 (3.2), with 65% having the prevalence of poor sleep quality (defined as PSQ ≥ 5; n = 311). The mean (SD) score for Insomnia Severity Index (ISI) was 6.9 (5.2), with 55 subjects (11.5%) having clinical insomnia (defined as ISI ≥ 15); of whom 9% had severe clinical insomnia. There were positive correlations between PSQI and ISI (r = 0.76, p < 0.001), PROMIS fatigue scale (r = 0.53, p < 0.001), Generalized Anxiety Disorder-7 (GAD-7) (r = 0.46, p < 0.001), and Perceived Stress Scale (PSS) (r = 0.44, p < 0.001). The PSQI was inversely correlated with the John Henryism Active Coping Scale (JHACS) and memory scale. In the multivariate regression model, JHACS, ISI, fatigue, PSS and GAD-7 were significant predictors of PSQI, and these variables accounted for 62% of the variance of PSQI, adjusted for age and gender. Conclusion: An important contribution to the literature is made by this research, which demonstrates the significant prevalence of poor sleep quality and its association with insomnia and other mental and physical well-being. It also underlines the need to prioritise policy and public health efforts to address sleep issues that have substantial health and economic effects for both individuals and the population at large.

An analysis of the factors affecting children and adolescent lifestyle in South Korea: A cross-sectional study with KCYPS 2018

Objective

The purpose of this study is to identify lifestyle factors that affect the subjective health conditions of adolescents in South Korea by utilizing data from the Korean Children’s and Youth Panel Survey 2018 conducted in Korea.

Methods

This cross-sectional study used data from 4,490 students (2,399 students in the fourth grade of elementary school and 2,541 students in the first grade of middle school). The data obtained were evaluated using living time (sleep time, study time, leisure time), emotions (happiness, self-esteem, emotional problems), capabilities (cooperative attitude, grit), health (life satisfaction, exercise time, number of breakfasts, quality of sleep), media (smartphone use and dependence), school (school life satisfaction, relationship with friends and teachers), and home (time spent with parents, parenting attitude).

Results

We confirmed that regardless of grade, living time (leisure time), emotion (happiness, self-esteem, emotional problems), capabilities (grit), health (life satisfaction, exercise time, quality of sleep), media (smartphone dependence), and school (school life satisfaction, friendly, and teacher relations) are related to subjective health conditions. These results confirmed that evaluation parameters are related to subjective health conditions regardless of grade.

Conclusion

This investigation revealed that the higher the quality of sleep enhanced positive emotions while increased exercise

Factors associated with seeking medical care for low back pain in a twin adult sample

BACKGROUND

Previous studies have only investigated how symptom presentation and socio-demographic factors influence care-seeking for low back pain (LBP). However, the influence of health and lifestyle factors remains unclear, and the potential confounding effects of aggregated familial factors (including genetics and the early shared environment) has not been considered extensively.

METHODS

A cross-sectional analysis was performed on 1605 twins enrolled in the Murcia Twin Registry (Spain). The outcome was seeking medical care for LBP and various self-reported demographic, health and lifestyle factors were considered predictors. All variables except sleep quality and diabetes were collected in 2013, which were cross-referenced from 2009 to 2010. A multivariate logistic regression model was performed on the total sample, followed by a co-twin case-control analysis.

RESULTS

The only significant factor found to increase the odds of seeking medical care for LBP without being affected by familial factors was poor sleep quality (total sample OR = 1.58, 95%CI 1.24-2.01; case-control OR = 1.75, 95%CI 1.14-2.69). The factors that were associated with reduced odds of seeking medical care for LBP and not confounded by familial factors were male sex (case-control OR = 0.55, 95%CI 0.33-0.93), alcohol intake (case-control OR = 0.90, 95%CI 0.82-0.99) and a history of diabetes (case-control OR = 0.50, 95%CI 0.25-0.97). No other factors significantly influenced medical care-seeking for LBP.

CONCLUSIONS

People reporting poor sleep quality are more likely to seek medical care for LBP in the long term, with this relationship being independent from aggregated familial factors. Conversely, males, people reporting higher alcohol intake, and people with a history of diabetes are less likely to seek medical care for LBP.

SIGNIFICANCE

This is the first study investigating the factors that influence seeking medical care for LBP, while adjusting for the influence of familial factors using a co-twin control design. Poor sleep quality is associated with seeking medical care for LBP in the long term and does not appear to be confounded by familial factors. Early screening for indicators of poor sleep quality and appropriate referral to interventions for improving sleep quality or reducing pain in sleep may improve LBP management.

Sleeve gastrectomy in patients with severe obesity restores circadian rhythms and their relationship with sleep pattern

Advances in research have linked alterations of circadian rhythms with obesity. However, few studies have focused on the recovery of the circadian expression after a weight loss treatment. Our aim was to study the alterations of the circadian rhythmicity due to morbid obesity and the recovery of the circadian pattern after weight loss in a cohort of patients who underwent sleeve gastrectomy. For this purpose, 41 patients with severe obesity (75% women; age [mean (SD)] 49.7 ± 10 years; BMI 44.3 ± 6.2 kg/m2) were monitored before bariatric surgery and 9 months afterward. On both occasions, activity and wrist temperature were determined by actigraphy and were related with weight loss. Anthropometric, biochemical, and sleep-related variables, along with dietary intake and physical activity, were analyzed in relation with circadian rhythmicity. Results show significant differences in the circadian expression before and after 9 months of bariatric surgery, with more stable and less fragmented rhythms after weight loss. Moreover, only after surgery were the circadian variables associated to sleep timing and chronotype. The findings of this study indicate that weight loss treatment in patients with morbid obesity improves the circadian rhythm expression, and in such a way that it could be associated with better sleep quality. Moreover, it allows the recovery of the relationship between sleep patterns and circadian rhythm that was lost due to the obesity.

Sleep Quality, Mental and Physical Health: A Differential Relationship

This study aimed to explore the association between sleep quality and its components and both dimensions of health-related quality of life (HRQoL) in a sample of young adults. The sample comprised 337 participants with a mean age of 19.6 y (SD = 2.22). Sleep quality and HRQoL were measured through the Pittsburgh Sleep Quality Index and the SF-12, respectively. Regression analyses were used to investigate the association between sleep quality and HRQoL. Our results confirm the significant association between sleep quality and both physical (p = 0.015; β = −0.138; R² = 0.07) and mental (p < 0.001; β = −0.348; R² = 0.22) HRQoL in the adjusted models. However, our results also highlight the differential association between sleep quality and mental and physical HRQoL. Whereas all the sleep quality components (except sleep latency; p = 0.349) were significantly associated with mental HRQoL (p < 0.05), just two subscales (subjective sleep quality; p = 0.021; β = −0.143 and sleep disturbances p = 0.002; β = −0.165) showed a significant association. This study showed that there is a stronger association between sleep quality and mental health than sleep quality and physical health in young adults.

Direct and indirect effects of poor sleep quality on BMI and waist circumference in a female population-based study in Southern Brazil

OBJECTIVE

This study aimed to investigate the direct and indirect effects of poor sleep quality on BMI and waist circumference (WC), considering behavioural factors as intermediate variables.

DESIGN

A population-based cross-sectional study design was adopted. Data were collected between February and October 2015. Poor sleep quality was assessed using the Brazilian version of the Pittsburgh Sleep Quality Index (PSQI-BR). Weight, height (used to calculate BMI) and WC were measured using standard protocols. Physical activity, sedentary behaviour and fast food consumption were considered intermediate variables. Non-standardised effects were estimated by path analysis with bootstrapped CI.

SETTING

Urban region of the city of São Leopoldo, southern Brazil.

PARTICIPANTS

Representative sample of 1117 women aged between 20 and 69 years.

RESULTS

Poor sleep quality (higher PSQI-BR scores) was significantly associated with low physical activity levels (β = -0·05; 95 % CI -0·09, -0·01). High physical activity levels were associated with lower BMI (β = -0·21; 95 % CI -0·37, -0·07) and WC (β = -0·64; 95 % CI -1·00, -0·30). There was a non-significant direct effect of poor sleep quality on BMI and WC. However, low physical activity showed a significant indirect effect on the association between poor sleep quality and increased WC (β = 0·03; 95 % CI 0·01, 0·07).

CONCLUSIONS

The results indicate that the association between sleep quality and WC is mediated by physical activity. This finding can assist in the development of strategies to prevent and reduce abdominal obesity in adult women.

Maternal Sleep Quality is Associated with Personal and Parenting Weight-Related Behaviors

Mothers of young children tend to report poor-quality sleep, yet little is known about links between maternal sleep quality and weight-related behaviors and parenting practices. Thus, mothers of preschoolers completed an online cross-sectional survey assessing their sleep, physical activity, dietary behaviors, eating styles, child feeding practices, family meal behaviors, and health parameters. Comparisons by sleep quality using the Pittsburgh Sleep Quality Index item (i.e., very bad/bad, n = 87; fair, n = 255; and good/very good, n = 193) revealed mothers with poor-quality sleep had weight-related behaviors associated with higher Body Mass Index (BMI) (lower physical activity, fewer fruits/vegetables, more emotional and disinhibited eating). Poor-quality sleepers also engaged in parenting practices contrary to recommendations, such as less frequent modeling of healthy eating and physical activity, more control of child feeding, and fewer family meals. Mothers reporting poor-quality sleep tended to have lower parenting self-efficacy, poorer overall health status, more days of poor mental and physical health, greater depression, more stress, and higher BMIs. Future nutrition research should establish the directionality between sleep quality and health behaviors. Future interventions should help mothers develop strategies for improving sleep quality, such as increased physical activity and fruit and vegetable intake, and helping mothers realize how their sleep quality may affect parenting practices.

Fluoride exposure and sleep patterns among older adolescents in the United States: a cross-sectional study of NHANES 2015-2016

BACKGROUND

Fluoride from environmental sources accumulates preferentially in the pineal gland which produces melatonin, the hormone that regulates the sleep-wake cycle. However, the effects of fluoride on sleep regulation remain unknown. This population-based study examined whether chronic low-level fluoride exposure is associated with sleep patterns and daytime sleepiness among older adolescents in the United States (US).

METHOD

This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (2015-2016). We analyzed data from adolescents who had plasma fluoride (n = 473) and water fluoride (n = 419) measures and were not prescribed medication for sleep disorders. Relationships between fluoride exposure and self-reported sleep patterns or daytime sleepiness were examined using survey-weighted linear, binomial logistic or multinomial logistic regression after covariate adjustment. A Holm-Bonferroni correction accounted for multiple comparisons.

RESULTS

The average age of adolescents was 17 years (range = 16-19). Median (IQR) water and plasma fluoride concentrations were 0.27 (0.52) mg/L and 0.29 (0.19) μmol/L respectively. An IQR increase in water fluoride was associated with 1.97 times higher odds of reporting symptoms suggestive of sleep apnea (95% CI: 1.27, 3.05; p = 0.02), a 24 min later bedtime (B = 0.40, 95% CI: 0.10, 0.70; p = 0.05), a 26 min later morning wake time (B = 0.43, 95% CI: 0.13, 0.73; p = 0.04), and among males, a 38% reduction in the odds of reporting snoring (95% CI: 0.45, 0.87, p = 0.03).

CONCLUSIONS

Fluoride exposure may contribute to changes in sleep cycle regulation and sleep behaviors among older adolescents in the US. Additional prospective studies are warranted to examine the effects of fluoride on sleep patterns and determine critical windows of vulnerability for potential effects.

An Update of Twin Research in Spain: The Murcia Twin Registry

The Murcia Twin Registry (MTR) is the only population-based registry in Spain. Created in 2006, the registry has been growing more than a decade to become one of the references for twin research in the Mediterranean region. The MTR database currently comprises 3545 adult participants born between 1940 and 1977. It also holds a recently launched satellite registry of university students (N = 204). Along five waves of data collection, the registry has gathered questionnaire and anthropometric data, as well as biological samples. The MTR keeps its main research focus on health and health-related behaviors from a public health perspective. This includes lifestyle, health promotion, quality of life or environmental conditions. Future short-term development points to the expansion of the biobank and the continuation of the collection of longitudinal data.

Weight Loss in Women Taking Flibanserin for Hypoactive Sexual Desire Disorder (HSDD): Insights Into Potential Mechanisms

INTRODUCTION

Flibanserin, a multifunctional serotonin receptor agonist and antagonist, is currently approved in the United States and Canada for the treatment of acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. A post hoc analysis of HSDD clinical trial data found that flibanserin treatment was associated with statistically significant weight loss relative to placebo, even though study patients were not selected for being overweight/obese and were provided no expectation for weight reduction or interventions intended to promote weight loss.

AIM

To understand possible mechanisms by which flibanserin may produce weight loss.

METHODS

A literature review was performed using Medline database for relevant publications on the mechanisms of action by which flibanserin may provide weight loss and the links between sexual function and weight management.

MAIN OUTCOME MEASURES

Examination of (i) biopsychosocial factors regulating sexual desire, food intake, and weight regulation; (ii) clinical pharmacology of flibanserin; (iii) neurobiology of brain reward circuitry; and (iv) identification of possible mechanisms common to flibanserin and weight loss.

RESULTS

Based on flibanserin clinical trial data, there was no consistent correlation between weight loss and improvement in sexual function, as assessed by HSDD outcome measures. Nausea, a common adverse event associated with flibanserin use, also did not appear to be a contributing factor to weight loss. Hypothetical links between flibanserin treatment and weight loss include modulation of peripheral 5-HT_2A receptors and factors such as improved mood and improved sleep.

CONCLUSION

Mechanisms of flibanserin-induced weight loss have not been well characterized but may involve indirect beneficial effects on peripheral 5-HT_2A receptors and central regulation of mood and sleep. Future research may better elucidate the links between sexual function and weight management and the mechanism(s) by which flibanserin use may result in weight loss. Simon JA, Kingsberg SA, Goldstein I, et al. Weight Loss in Women Taking Flibanserin for Hypoactive Sexual Desire Disorder (HSDD): Insights into Potential Mechanisms. Sex Med Rev 2019;7:575-586.

Does sleep influence weight gain during pregnancy? A prospective study

Objective

The focus of this study was to evaluate the associations between subjective sleep quality and duration and weight gain during pregnancy.

Methods

A prospective and longitudinal study was conducted with 63 pregnant women. Pregnant women were evaluated at the first, second and third trimester for subjective sleep quality (Pittsburgh Sleep Quality Index [PSQI]) and anthropometric variables for body mass index [BMI] calculation. The sleep quality was grouped per cluster, identifying those individuals who maintained, improved or worsened their sleep quality, based on the PSQI classifications. Generalized estimating equations (GEE) were used to examine the association between sleep and BMI over the pregnancy period.

Results

An effect of the interaction between time of pregnancy and clusters of sleep quality was observed on the BMI (p<0.05), which indicates that pregnant women who improved subjective sleep quality during pregnancy gained more weight from the second to third trimester, while those that worsened the subjective sleep quality gained more weight during the first to second trimester. Sleep duration was not associated with weight gain. However, pregnant women who maintained the same BMI category over the pregnancy period increased their sleep duration from the first to third trimester, while those that increased the BMI category slept the same amount of time during this period (median=1.0 [0.0-2.0] and median=0.0 [-2.0-1.0], respectively, p=0.039).

Conclusions

The authors concluded that a worse subjective sleep quality seems to lead to an inadequate weight gain distribution during the period of pregnancy.

Habitual Sleep Measures are Associated with Overall Body Fat, and not Specifically with Visceral Fat, in Men and Women

OBJECTIVE

This study aimed to investigate the associations of sleep duration and sleep quality with visceral adipose tissue (VAT) in middle-aged individuals.

METHODS

In this cross-sectional analysis of baseline measurements of the Netherlands Epidemiology of Obesity (NEO) study, participants underwent anthropometry and completed the Pittsburgh Sleep Quality Index (PSQI) for assessing short sleep duration (as sex-specific age-adjusted percentiles) and poor quality (PSQI > 5). VAT was assessed by magnetic resonance imaging in a random subgroup. We performed linear regression analyses to examine associations of short sleep and poor sleep with measures of body fat, adjusted for confounding, including total body fat in models with VAT.

RESULTS

A total of 5,094 participants (52% women; mean age of 56 [SD 6] years), 1,947 of whom had VAT measurements, were analyzed. The difference in VAT between poor sleep (PSQI > 5) and good sleep (PSQI ≤ 5) was 7.2cm² (95% CI: 1.2-13.8) in women and 16.1cm² (95% CI: 6.2-26.0) in men. These differences attenuated toward the null after the adjustment for total body fat. Similar patterns of associations were observed for short sleep (lowest 10% compared with median 60%).

CONCLUSIONS

Our results suggest that measures of sleep are not specifically associated with a higher amount of VAT.