Association between body mass index and mental health among Scottish adult population: a cross-sectional study of 37,272 participants

Dose-Dependent Association Between Body Mass Index and Mental Health and Changes Over Time

Importance

Overweight and obesity affect 340 million adolescents worldwide and constitute a risk factor for poor mental health. Understanding the association between body mass index (BMI) and mental health in adolescents may help to address rising mental health issues; however, existing studies lack comprehensive evaluations spanning diverse countries and periods.

Objective

To estimate the association between BMI and mental health and examine changes over time from 2002 to 2018.

Design, Setting, and Participants

This was a repeated multicountry cross-sectional study conducted between 2002 and 2018 and utilizing data from the Health Behaviour in School-aged Children (HBSC) survey in Europe and North America. The study population consisted of more than 1 million adolescents aged 11 to 15 years, with all surveyed children included in the analysis. Data were analyzed from October 2022 to March 2023.

Main Outcomes and Measures

Mental health difficulties were measured by an 8-item scale for psychological concerns, scoring from 0 to 32, where a higher score reflects greater psychosomatic issues. BMI was calculated using weight divided by height squared and adjusted for age and sex. Data were fitted by multilevel generalized additive model. Confounders included sex, living with parents, sibling presence, academic pressure, the experience of being bullied, family affluence, screen time, and physical activity.

Results

Our analysis of 1 036 869 adolescents surveyed from 2002 to 2018, with a mean (SD) age of 13.55 (1.64) years and comprising 527 585 girls (50.9%), revealed a consistent U-shaped association between BMI and mental health. After accounting for confounders, adolescents with low body mass and overweight or obesity had increased psychosomatic symptoms compared to those with healthy weight (unstandardized β, 0.14; 95% CI, 0.08 to 0.19; unstandardized β, 0.27; 95% CI, 0.24 to 0.30; and unstandardized β, 0.62; 95% CI, 0.56 to 0.67, respectively), while adolescents with underweight had fewer symptoms (unstandardized β, -0.18; 95% CI, -0.22 to -0.15). This association was observed across different years, sex, and grade, indicating a broad relevance to adolescent mental health. Compared to 2002, psychosomatic concerns increased significantly in 2006 (unstandardized β, 0.19; 95% CI, 0.11 to 0.26), 2010 (unstandardized β, 0.14; 95% CI, 0.07 to 0.22), 2014 (unstandardized β, 0.48; 95% CI, 0.40 to 0.56), and 2018 (unstandardized β, 0.82; 95% CI, 0.74 to 0.89). Girls reported significantly higher psychosomatic concerns than boys (unstandardized β, 2.27; 95% CI, 2.25 to 2.30). Compared to primary school, psychosomatic concerns rose significantly in middle school (unstandardized β, 1.15; 95% CI, 1.12 to 1.18) and in high school (unstandardized β, 2.12; 95% CI, 2.09 to 2.15).

Conclusions and Relevance

Our study revealed a U-shaped association between adolescent BMI and mental health, which was consistent across sex and grades and became stronger over time. These insights emphasize the need for targeted interventions addressing body image and mental health, and call for further research into underlying mechanisms.

Dose-response association of obesity and risk of mental health among tehranian residents: result of a cross-sectional study

BACKGROUND

Obesity and mental health issues are two of the most prevalent global public health issues for a significant portion of people. The purpose of this study was to investigate the relationship between obesity indicators and mental health in Tehran-dwelling Iranian adults.

METHODS

We conducted a cross-sectional study on healthy Iranian adults using a convenience sampling technique. The short form of the Depression Anxiety and Stress Scale (DASS-21) was used to measure the outcome, and independent variables included body mass index (BMI), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR), body adiposity index (BAI), and a body shape index (ABSI). The relationship between obesity and mental health was investigated using a multivariate logistic regression model. The non-linear dose-response relationships were evaluated using restricted cubic splines (RCS) with three knots. The Benjamini-Hochberg procedure was used to adjust for multiple testing.

RESULTS

In our study of 434 participants, females made up 52% of the participants, with a mean age of 38.57 years. In all, 54.6%, 53.9%, and 56.6% were classified as having anxiety, depression, and stress respectively. Logistic regression analysis showed that the odds of mental health components including anxiety, depression, or stress was not significantly different across the tertiles of the obesity indicators. We observed a significant dose-response relationship between BAI and ABSI and the risk of anxiety (PBenjamini-Hochberg 0.028 > Pdose-response 0.023) and stress (PBenjamini-Hochberg 0.028 > Pdose-response 0.003) but not depression (PBenjamini-Hochberg 0.014 < Pdose-response 0.018). The lowest risk for anxiety was observed in people with a BAI of 28% and ABSI equal to 0.079. The risk of stress seemed to increase beyond an ABSI of 0.086.

CONCLUSION

Our findings showed no direct linear association between obesity indices and anxiety. However, a dose-response relationship was observed between BAI and ABSI and the risk of anxiety and stress, indicating the need for further investigation.

Associations between muscular strength and mental health in cognitively normal older adults: a cross-sectional study from the AGUEDA trial

Objective

To examine the associations between muscular strength and mental health.

Design

We used baseline data of 91 cognitively healthy older adults (71.69 ± 3.91 years old, 57 % women) participating in the AGUEDA randomized controlled trial.

Methods

Muscular strength was assessed using both objective (i.e., handgrip strength, biceps curl, squats, and isokinetic test) and perceived (i.e., International Fitness Scale) indicators. Psychological ill-being indicators: anxiety, depression, stress, and loneliness; and psychological well-being indicators: satisfaction with life, self-esteem, and emotional well-being) were assessed using a set of valid and reliable self-reported questionnaires. Linear regression analyses were performed adjusting for sex, age, years of education, body mass index , alcohol, diet, and smoking (model 1), and additionally by cardiorespiratory fitness (model 2).

Results

Elbow extension was positively associated with stress in model 1 (β = 0.252, 95 % Confidence Interval [95 % CI] = 0.007 to 0.497, p = 0.044), and even after further adjustment for cardiorespiratory fitness (β = 0.282, 95 % CI = 0.032 to 0.532, p = 0.028). Perceived strength was negatively associated with depressive symptoms in model 1 (β = -0.271, 95 % CI = -0.491 to -0.049, p = 0.017) and model 2 reported associations tending towards significant (β = -0.220, 95 % CI = -0.445 to 0.005, p = 0.055). Handgrip strength was positively associated with self-esteem in model 1 (β = 0.558, 95 % CI = 0.168 to 0.949, p = 0.006) and model 2 (β = 0.546, 95 % CI = 0.135 to 0.956, p = 0.010). No further associations were found among other muscular strength and mental health variables.

Conclusion

Handgrip had a moderate association with self-esteem and there was a small association between perceived strength with depressive symptoms and elbow extension with stress. No other associations were observed between muscular strength and mental health outcomes in cognitively normal older adults.

Interpreting the Evidence of Body Mass Index in Relation to Mental Health Status in Community-Dwelling Older Adults

INTRODUCTION

Maintaining a better physical and mental health status is an important issue for older adults in their later life. Thus, the study's purpose was to evaluate the association between body mass index (BMI) and mental health status in older adults aged 65 years old or above residing in communities of Taipei City, Taiwan.

METHODS

We carried out secondary data analysis with data from a volunteer-based health examination project for older adults >65 years old residing in Taipei City from 2006 to 2010 with a retrospective study design. BMI, calculated by standardized measuring procedures for height and weight, and mental health status, evaluated by 5-item Brief Symptom Rating Scale (BSRS-5), were collected at their first visits of health examination. A BSRS-5 score ≥6 was considered an inferior mental health status for the outcome. In statistical analysis, univariable and multivariable logistic regressions were adopted to estimate the relative risk of inferior mental health status, treating BMI as the major exposure of interest.

RESULTS

A total of 90,576 subjects were involved, with a mean age of 73.38 years old (SD = 6.64 years) and 49.21% females. With confounders controlled, compared to normal or overweight (23 ≤ BMI <30), an adjusted OR of 1.23 (95% CI: 1.18, 1.29) on inferior mental health status was detected for the underweight group (BMI <23) significantly. Adjusted OR for those obese (BMI ≧30) was 0.87 (95% CI: 0.79, 0.96). Significantly elevated ORs of underweight were found for both genders, but the significantly protective effect of obese was only detected for females.

CONCLUSION

Keeping an appropriate weight or even being overweighted might be beneficial for older adults dwelling in the community, especially for males.

Lifestyle predictors for inconsistent participation to fecal based colorectal cancer screening

BACKGROUND

Consistent participation in colorectal cancer (CRC) screening with repeated fecal immunochemical test (FIT) is important for the success of the screening program. We investigated whether lifestyle risk factors for CRC were related to inconsistent participation in up to four rounds of FIT-screening.

METHOD

We included data from 3,051 individuals who participated in up to four FIT-screening rounds and returned a lifestyle questionnaire. Using logistic regression analyses, we estimated associations between smoking habits, body mass index (BMI), physical activity, alcohol consumption, diet and a healthy lifestyle score (from least favorable 0 to most favorable 5), and inconsistent participation (i.e. not participating in all rounds of eligible FIT screening invitations).

RESULTS

Altogether 721 (24%) individuals were categorized as inconsistent participants Current smoking and BMI ≥30 kg/m2 were associated with inconsistent participation; odds ratios (ORs) and 95% confidence intervals (CIs) were 1.54 (1.21-2.95) and 1.54 (1.20-1.97), respectively. A significant trend towards inconsistent participation by a lower healthy lifestyle score was observed (p < 0.05).

CONCLUSIONS

Lifestyle behaviors were associated with inconsistent participation in FIT-screening. Initiatives aimed at increasing participation rates among those with the unhealthiest lifestyle have a potential to improve the efficiency of screening.

Weight change and mental health according to obesity in relatively healthy middle-aged Korean women: The Korea National Health and Nutrition Examination Survey 2014, 2016, 2018

BACKGROUND

Obesity is a known risk factor for various chronic conditions, as well as mental health disorders. However, there have been few studies on weight change and mental health according to obesity. This study was performed to elucidate the association between weight changes and mental health according to obesity in middle-aged women.

METHODS

Data from the Korean National Health and Nutrition Examination Survey (2014, 2016, 2018), which included 3953 women aged 40 to 59, were used in this study. After excluding those who had chronic conditions possibly affecting weight change, 2964 women were included in the study. The associations between weight changes and mental health, including perceived stress, depressed mood surveyed by the patient health questionnaire-9(PHQ-9), and current depressive disorder were analyzed.

RESULTS

Weight change in non-obese and obese women was associated with poorer mental health, including perceived stress and depressed mood (p<0.05), although the significance disappeared in covariates-adjusted analysis in obese women. Both non-obese and obese women with weight gain had higher perceived stress than women with weight loss, while in the PHQ-9 scores, higher scores were observed in non-obese women with weight gain, and in obese women with weight loss.

LIMITATIONS

Our study could not define causality because this was a cross-sectional study. And the information on body weight change was obtained by self-reported questionnaires.

CONCLUSIONS

Our study suggested that in relatively healthy middle-aged Korean women, weight change was a significant factor associated with mental health, but obesity itself was not.

Interval training causes the same exercise enjoyment as moderate-intensity training to improve cardiorespiratory fitness and body composition in young Chinese women with elevated BMI

This study examined the effects of 12 weeks of sprint interval training (SIT), high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) on cardiorespiratory fitness (peak oxygen uptake, VO_2peak), body composition and physical activity enjoyment in overweight young women. Sixty-six participants (age 21.2 ± 1.4 years, body mass index (BMI) 26.0 ± 3.0 kg·m^-2, body fat percentage 39.0 ± 2.8%) were randomly assigned to non-exercise control (CON), thrice-weekly SIT (80 × 6 s "all-out" cycling interspersed with 9 s rest), and HIIT (4 min cycling at 90% VO_2peak followed with 3 min recovery for ~ 60 min) or MICT (~ 65 min continuous cycling at 60% VO_2peak) with equivalent mechanical work (200/300 KJ). Compared to the CON group, all three training groups had significant and similar improvements in VO_2peak (~ +20%, d = 2.5-3.4), fat mass (~ -10%, d = 1.3-2.1) and body fat percentage (~ -5%, d = 1.0-1.1) after a 12-week intervention. Similar high levels of enjoyment were observed among groups for most (~70%) of the training sessions. The findings suggest that the three training regimes are equally enjoyable and could result in similar improvements in cardiorespiratory fitness and body composition in overweight/obese young women, but SIT is a more time-efficient strategy.

Higher HEI-2015 Score Is Associated with Reduced Risk of Depression: Result from NHANES 2005-2016

Globally, the total estimated number of people living with depression increased by 18.4% between 2005 and 2015, with the prevalence being 4.8% in 2015. Many nutrient and diet patterns are proven to be correlated to depression, so we conducted this analysis to explore whether the Healthy Eating Index 2015 (HEI-2015) score is associated with depression, and possibly to provide dietary measures to reduce the risk of depression. Data came from the National Health and Nutrition Examination Survey (2005–2016), a cross-sectional and nationally representative database. The analytic sample was limited to adults: (1) age ≥20 with complete information of HEI-2015 and depression; (2) no missing data of demographics, BMI, drinking, smoking, and fasting plasma glucose. HEI-2015 was calculated using the Dietary Interview: Total Nutrient Intakes, First Day data file. Depression was assessed using the Patient Health Questionnaire-9 (PHQ-9). Weighted logistic regression models were used to explore the relationship between the HEI-2015 score and depression. The final study sample included 10,349 adults, with 51.4% of them being men, representing a population of about 167.8 million non-institutionalized U.S. adults. After multivariable adjustment, average HEI status (OR: 0.848, 95% CI: 0.846–0.849) and optimal HEI status (OR: 0.455, 95% CI: 0.453–0.456) were associated with reduced odds of depression. Poor diet quality is significantly associated with elevated depressive symptoms in U.S. adults. Aligning with the Dietary Guidelines for Americans reduces the risk of depression.

Mental Health Status of the Elderly Chinese Population During COVID-19: An Online Cross-Sectional Study

Background: COVID-19 not only threatened the public's physical health but also brought unbearable psychological pressure, especially for those vulnerable groups like the elderly. However, studies on the psychological status of older adults during this public health emergency remained scant. This study aims to investigate the mental health status among the elderly Chinese population during COVID-19 pandemic and determine the influencing factors of psychological symptoms. Methods: From February 19 to March 19, 2020, an online survey was administered to Chinese older adults using a convenience sampling method. Information on demographic data, health status and other epidemic related factors were collected. Specifically, the study defined the psychological status as five primary disorder-depression, neurasthenia, fear, anxiety, and hypochondria-which were assessed by the Psychological Questionnaire for Emergent Event of Public Health (PQEEPH). Standard descriptive statistics and multiple logistic regression analyses were conducted to analyze the data. Results: Of 1,501 participants recruited from 31 provinces in China, 1,278 were valid for further analysis. Participants' scores on each sub-scale were described in median and interquartile [M(Q)]: depression [0.00 (0.33)], neurasthenia [0.00 (0.40)], fear [1.00 (0.83)], anxiety [0.00 (0.17)], hypochondria [0.00 (0.50)]. Chronic diseases (depression p = 0.001; neurasthenia p < 0.001; fear p = 0.023; anxiety p < 0.001; hypochondria p = 0.001) and the BMI index (depression p = 0.015; neurasthenia p = 0.046; fear p = 0.016; anxiety p = 0.015; hypochondria p = 0.013) had significant impacts on all of the five sub-scales. Specifically, the rural dwellers had a higher level of neurasthenia, fear, and hypochondria. Besides, education level (p = 0.035) and outbreak risk level (p = 0.004) had significant impacts on the depression. Higher household monthly income per capita (p = 0.031), and the community-level entry/exit control (p = 0.011) are factors against anxiety. Conclusions: Most elderly residents reported mild negative emotions during COVID-19 and more attention should be paid to the recognition and alleviation of fear. Our findings also identified factors associated with the mental health status of the elderly, which is of practical significance in the design and implementation of psychological interventions for this vulnerable population during COVID-19 and future emerging diseases.

Gender, income and mental health: The Turkish case

Gender gaps in health outcomes are frequently observed. Mental health disorders also display gender differences in various countries. This paper explores gender differences in mental health outcomes of individuals in Turkey. It aims to deliver additional evidence on associations between gender, income and mental health status by providing an empirical analysis from a developing country, Turkey. This study employs a nationally representative data set from Turkish Health Survey of 2016. It constructs an index for mental health at individual level by using polychoric principal component analysis. Conditional mixed process models are estimated for quantification of associations between gender, income and mental health measures. Empirical findings indicate that there is endogenous and positive relationship between household income level and mental health status of individuals in Turkey. Turkish females report lower mental health statuses than Turkish males. Furthermore, females are more likely to use mental health services in Turkey. Gender gaps in both mental health status and mental health service use are present in the Turkish case. Results of this study imply that mental health policies should avoid applying one-fit-all approaches.

Clinical outcomes of lumbar diseases specific test in patients who undergo endoscopy-assisted tubular surgery with lumbar herniated nucleus pulposus: an analysis using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ)

Purpose

This study was to evaluate clinical outcomes using a patient-oriented test that scores health-related quality of life (HRQOL) for patients after minimally invasive surgery using microendoscopic discectomy (MED) for lumbar disc hernia. Few studies regarding MED in terms of disease-specific quality of life measures using Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) have been published.

Methods

Retrospective analysis of the surgical and clinical outcomes with regard to reducing pain and improving the functional status for 31 patients who underwent MED for lumbar disc hernia was conducted. These patients were evaluated at 3-year follow-up. The evaluations were based on a visual analogue scale (VAS), the Japanese Orthopaedic Association (JOA) scoring system, and the JOABPEQ, which is an objective, patient-oriented test that assesses HRQOL in patients with lumbar disorders.

Results

A low rate of improvement was seen only in mental health until 1 year, the low rate of improvement in mental health and was independently correlated with body mass index (BMI), pre-operative scores on the Brief Scale for Psychiatric problems in Orthopaedic Patients (BS-POP), and scores on the BS-POP at 12 months post-operatively.

Conclusions

All categories of VAS, JOA scores, and all domains of JOABPEQ were significantly higher over 3 years than those obtained pre-operatively. But only mental health domain showed mild improvement until 1 year. Moreover, BMI showed a negative correlation with improvements in the mental health domain post-operatively. As patients may be mentally exhausted from lumbar disc herniation, pre-operative mental health may be improved by surgical treatment.

Variance Components Models for Analysis of Big Family Data of Health Outcomes in the Lifelines Cohort Study

Large multigenerational cohort studies offer powerful ways to study the hereditary effects on various health outcomes. However, accounting for complex kinship relations in big data structures can be methodologically challenging. The traditional kinship model is computationally infeasible when considering thousands of individuals. In this article, we propose a computationally efficient alternative that employs fractional relatedness of family members through a series of founding members. The primary goal of this study is to investigate whether the effect of determinants on health outcome variables differs with and without accounting for family structure. We compare a fixed-effects model without familial effects with several variance components models that account for heritability and shared environment structure. Our secondary goal is to apply the fractional relatedness model in a realistic setting. Lifelines is a three-generation cohort study investigating the biological, behavioral, and environmental determinants of healthy aging. We analyzed a sample of 89,353 participants from 32,452 reconstructed families. Our primary conclusion is that the effect of determinants on health outcome variables does not differ with and without accounting for family structure. However, accounting for family structure through fractional relatedness allows for estimating heritability in a computationally efficient way, showing some interesting differences between physical and mental quality of life heritability. We have shown through simulations that the proposed fractional relatedness model performs better than the standard kinship model, not only in terms of computational time and convenience of fitting using standard functions in R, but also in terms of bias of heritability estimates and coverage.

The influence of dietary patterns and stressful life events on psychological problems in a large sample of Iranian industrial employees: Structural equations modeling approach

BACKGROUND

Psychological problems affect many employees and their job performance. Although, the association of diet and stress, as modifiable risk factors, with psychological problems have been investigated separately, however their simultaneous impacts have not been studied. The present study aimed at reinvestigating the association of major dietary patterns and stressful life events with intensity of psychological problems in a large sample of Iranian industrial employees.

METHODS

In a cross-sectional study, 3063 employees in an industrial unit in Isfahan, Iran were investigated. Psychological problems profile as a latent construct was extracted from three common psychological problems; depression, anxiety and psychological distress. Depression and anxiety were measured by Persian validated version of Hospital Anxiety and Depression Scale (HADS) and psychological distress by the 12 items General Health Questionnaires (GHQ). Major dietary patterns were derived from a validated short form of semi-quantitative Food Frequency Questionnaire (FFQ) using explanatory factor analysis. Stressful life events dimensions were extracted based on factor analysis, from self-perceived frequency and intensity of Stressful Life Events (SLE) questionnaire. Associations of the obtained factors were investigated in a latent structural modeling framework.

RESULTS

Three dietary patterns i.e. western, traditional and healthy and two stressors dimensions including personal life and socioeconomics were extracted. Greater adherence to healthy diet was protectively associated with psychological problems profile scores (β = -0.54; 95% CI: -0.74, -0.34). Adherence to western (β = 0.23; 95% CI: 0.02, 0.45) and Iranian traditional (β = 0.48; 95% CI: 0.28, 0.68) dietary patterns were positively associated with higher psychological problems scores in employees. But after adjustment for life stressors only adherence to a healthy diet remained significantly associated with psychological problems profile (β = -0.43; 95% CI: -0.59, -0.27). Also, personal life stressors (β = 0.81; 95% CI: 0.63, 0.99) and socioeconomics stressors (β = 0.12; 95% CI: 0.08, 0.16) had significantly direct association with psychological problems profile scores.

LIMITATIONS

Variables assessment by self-reported questionnaires, not affording causality because of cross sectional design, not adjusting the nutrients intake in association analyses, relatively small sample size of women.

CONCLUSIONS

Life stressors particularly personal stressors have negative direct association with psychological health of employees. Adherence to a healthy diet can be related to improvement of psychological health in employees. The results can be useful in occupational health planning in order to improve mental health and job productivity.

Prevalence and Association of Obesity with Self-Reported Comorbidity: A Cross-Sectional Study of 1321 Adult Participants in Lasbela, Balochistan

Association of fatness with chronic metabolic diseases is a well-established fact, and a high prevalence of risk factors for these disorders has increasingly been reported in the third world. In order to incorporate any preventive strategies for such risk factors into clinical practice, decision-makers require objective evidence about the associated burden of disease. A cross-sectional study of 1321 adults from one of the districts of Balochistan, among the most economically challenged areas of Pakistan, was carried out for the measures of fatness and self-reported comorbidities. Body mass index (BMI), waist circumference (WC), and waist-to-hip ratio (WHR) were measured and demographic information and self-reported comorbidities were documented. The prevalence of obesity was 4.8% (95% CI: [3.8, 6.1]) and 21.7% (95% CI: [19.5, 24.0]), as defined by the World Health Organization (WHO) international and Asia/Asia-Pacific BMI cut-offs, respectively. The proportion exhibiting comorbidity increased with increasing levels of fatness in a dose-response relationship (p value < .001). An interaction of weight status with gender was observed to produce a significantly (p = .033) higher comorbidity among overweight women (odds ratio (OR) = 6.1 [1.2, 31.7]) compared with overweight men (OR = 1.1 [0.48, 2.75], p = .762).

Lifestyle predictors for non-participation and outcome in the second round of faecal immunochemical test in colorectal cancer screening

BACKGROUND

To reduce colorectal cancer (CRC) mortality through population-based screening programmes using faecal tests, it is important that individuals continue to participate in the repeated rounds of screening. We aimed to identify lifestyle predictors for discontinuation of faecal immunochemical test (FIT) screening after the first round, as well as lifestyle predictors for colorectal neoplasia detected in the second-round FIT screening.

METHODS

In this longitudinal study, we invited 6959 individuals aged 50-74 years from south-east Norway for a first round of FIT screening and to complete a self-reported lifestyle questionnaire on demographic factors, body mass index (BMI, kg m-2), smoking habits, physical activity, consumption of alcohol and dietary items. Two years later, we estimated the associations between these factors, non-participation and screening results in the second round of FIT screening using adjusted odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Of the 3114 responders to the questionnaire who completed the first-round FIT and who were invited to participate in second-round FIT screening, 540 (17%) did not participate. The OR and (95% CI) for discontinuation of FIT screening after the first round was 1.61 (1.24-2.10) for current smoking compared with non-smoking; 2.01 (1.25-3.24) for BMI⩾35 kg m-2 compared with BMI 16.9-24.9 kg m-2 and 0.70 (0.52-0.94) for physical activity in the third quartile vs the first. Among participants, smoking, high BMI and high alcohol consumption were associated with an increased odds of detecting colorectal neoplasia (n=107).

CONCLUSIONS

These results may indicate that Norwegian FIT screening participants who discontinue after the first round have lifestyle behaviours associated with increased risk of CRC.

A cross-sectional study of sociodemographic factors and their influence on quality of life in medical students at Sao Paulo, Brazil

Background

Various sociodemographic factors can affect the quality of life of medical students and interfere in their ability to study. A deeper understanding of these factors may facilitate improvements in learning and retention of medical students.

Methods

We conducted a cross-sectional study of 405 medical students, representing 65.3% of the total student body (years 1–6), at a private medical school in São Paulo, Brazil. Among the entire study group, 177 students (43.7%) were male, and 228 (56.3%) were female. The mean age was 23.55 years (SD = 3.98 years, range: 18–40). The World Health Organization Quality of Life-Biomedical Research and Education Facility (WHOQOL-BREF) scale was used to evaluate the following sociodemographic factors: age, sex, academic year, daily traveling time, housing conditions, smoking, weight, height, participant’s and his/her parents’ education background, students who had a degree or not and religious beliefs. The reliability of the WHOQOL-BREF was evaluated using Cronbach’s analysis, and the association of sociodemographic factors with quality of life was examined using multivariate regression analysis.

Main Results

Quality of life was significantly higher in medical students with religious beliefs (β 0.14 for psychological domain; β 0.11 for environmental domain) when compared with that in those with no religious beliefs. BMI was negative associated with QOL in medical students (β -0.11 for physical domain; β -18.9 for the psychological domain). In both male and female students, longer daily traveling time was negative related to QOL (β -0.11 for environmental domain). Having at least one parent who was a doctor was associated with a better quality of life (β 0.17 for environmental domain). Male students presented with significantly higher mean scores for three of the four domains evaluated (β 0.20 for physical domain; β 0.25 for psychological domain; β 0.14 for social domain).

Conclusion

This study has provided novel insights into the effects of sociodemographic factors, physical traits, and religious beliefs on the quality of life of medical students. These findings may facilitate improvements in physical, psychological, and social support for medical students at a critical stage in their training, thereby providing tools for student better adjustment to medical school.

Association between salivary serotonin and the social sharing of happiness

Although human saliva contains the monoamine serotonin, which plays a key role in the modulation of emotional states, the association between salivary serotonin and empathic ability remains unclear. In order to elucidate the associations between salivary serotonin levels, trait empathy, and the sharing effect of emotions (i.e., sharing emotional experiences with others), we performed a vignette-based study. Participants were asked to evaluate their happiness when they experience several hypothetical life events, whereby we manipulated the valence of the imagined event (positive, neutral, or negative), as well as the presence of a friend (absent, positive, or negative). Results indicated that the presence of a happy friend significantly enhanced participants’ happiness. Correlation analysis demonstrated that salivary serotonin levels were negatively correlated with happiness when both the self and friend conditions were positive. Correlation analysis also indicated a negative relationship between salivary serotonin levels and trait empathy (particularly in perspective taking), which was measured by the Interpersonal Reactivity Index. Furthermore, an exploratory multiple regression analysis suggested that mothers’ attention during childhood predicted salivary serotonin levels. Our findings indicate that empathic abilities and the social sharing of happiness decreases as a function of salivary serotonin levels.

Association between weight status and men's positive mental health: The influence of marital status

The purpose of this study was to (1) examine the association between weight status and men's positive mental health, defined as the presence of symptoms of emotional, psychological, and social well-being, and (2) evaluate the moderating effect of marital status. A total of 645 men aged between 19 and 71 years self-reported their height and weight and answered a questionnaire measuring their emotional, psychological, and social well-being. Analysis of variance revealed that mean levels of emotional, psychological, and social well-being did not significantly differ according to men's weight status. Moderation analyses indicated that, for men in a relationship (married or living common-law), there were no significant associations between overweight, obesity, and the three components of positive mental health. However, for single men, overweight was marginally associated with higher emotional well-being, while obesity was associated with lower psychological well-being and marginally associated with lower social well-being. Results of the present study suggest that health professionals and researchers should take the characteristics (such as marital status) of men with obesity and overweight into account when working with them. Mental health researchers may need to examine men in each weight category separately (e.g. obesity vs. overweight), since the association with positive mental health can differ from one category to another.

Associations between behavioural risk factors and overweight and obesity among adults in population-based samples from 31 countries

OBJECTIVE

Concern about overweight and obesity is growing worldwide, and more research to examine behaviours associated with the risk for increased weight in adult populations is needed. The aim of this study was to estimate associations between behavioural risk factors and overweight and obesity among adults in nationally representative population samples from 20 countries in Europe, 8 countries in Asia, Australia, Chile and USA.

METHODS

This secondary analysis is based on the International Social Survey Program (ISSP), 2011-2013, Health and Health Care Module. In a cross-sectional population-based survey (N=48,741) (mean age 46.6 years, SD=17.4, age range 15-102 years) simple or multi-stage stratified random sampling was used, yielding representative samples of the adult population of respective countries. Body Mass Index was assessed by self-reported height and weight. Correlates were risk behaviours for chronic disease (smoking status, alcohol intake, consumption of fruits and vegetable (=FV), and physical activity).

RESULTS

Overall, for all 31 countries the prevalence of overweight or obesity was 44.1%, 31.7% overweight and 12.4% obese. In adjusted logistic regression models, among men and among women ex-smoking was positively associated with both overweight and obesity, while light or moderate smoking overall and among men were inversely related with obesity. Moderate alcohol use was positively associated with both overweight and obesity, while heavy alcohol use was negatively associated with overweight. The daily consumption of FV was found to be protective from both overweight and obesity, overall and for men but not for women. Physical activity was positively associated with overweight but not obesity.

CONCLUSIONS

Some risk behaviours for chronic disease appear to be associated with overweight and obesity among adults. Interventions targeting these risk behaviours may have the potential to reduce weight.

Major depressive disorder and current psychological distress moderate the effect of polygenic risk for obesity on body mass index

Major depressive disorder (MDD) and obesity are frequently co-morbid and this correlation is partly due to genetic factors. Although specific genetic risk variants are associated with body mass index (BMI) and with larger effect sizes in depressed individuals, the genetic overlap and interaction with depression has not been addressed using whole-genome data. Polygenic profile scores for MDD and BMI were created in 13,921 members of Generation Scotland: the Scottish Family Health Study and tested for their association with BMI, MDD, neuroticism and scores on the General Health Questionnaire (GHQ) (current psychological distress). The association between BMI polygenic profile scores and BMI was tested fitting GHQ, neuroticism or MDD status as an interaction term to test for a moderating effect of mood disorder. BMI polygenic profile scores were not associated with lifetime MDD status or neuroticism although a significant positive association with GHQ scores was found (P = 0.0001, β = 0.034, r(2) = 0.001). Polygenic risk for MDD was not associated with BMI. A significant interaction between BMI polygenic profile scores and MDD (P = 0.0003, β = 0.064), GHQ (P = 0.0005, β = 0.027) and neuroticism (P = 0.003, β = 0.023) was found when BMI was the dependent variable. The effect of BMI-increasing alleles was greater in those with MDD, high neuroticism or current psychological distress. MDD, neuroticism and current psychological distress amplify the effect of BMI polygenic profile scores on BMI. Depressed individuals with a greater polygenic load for obesity are at greater risk of becoming obese than control individuals.

Association between mental health and comorbid obesity and hypertension among children and adolescents in the US

This paper examines the association between mental health and comorbid obesity and hypertension among US children and adolescents using data from the National Health and Nutritional Examination Survey (NHANES). Questionnaires from NHANES were used to assess mental health during the previous 30 days. Respondents were then categorized into two groups namely "poor mental health" and "good mental health" based on their responses to these survey questions. Three multiple logistic regression models, based on these categories, are estimated to compute the odds ratios and 95% confidence intervals in the association of obesity and hypertension and mental health. As a select example, the results of Model 2 reveal that compared with respondents who are not obese, obese respondents have increased odds (OR = 1.24; P < 0.0001) of poor mental health. Furthermore compared with non-hypertensive respondents, hypertensive respondents have higher odds (OR = 2.96; P < 0.0001) of poor mental health. These findings have important implications for mental health management in younger populations. It brings into focus the maintenance of a healthy body mass index and hypertension control in mitigating poor mental health.

Association between physical and mental health-related quality of life and adverse outcomes; a retrospective cohort study of 5,272 Scottish adults

Background

Health-related quality of life (HRQoL) is associated with adverse outcomes in disease-specific populations. This study examines whether it is also independent predictor of incident cancer, coronary heart disease (CHD) and mortality in the general population.

Methods

The records of adult participants in the Scottish Health Survey 2003 were linked with hospital admissions, cancer registrations and death certificates. Cox proportional hazard models were used to explore the associations between quintiles of physical and mental component summary score (PCS and MCS respectively) of the SF-12 and adverse outcomes. Higher quintiles of both PCS and MCS indicate better health status.

Results

Among the 5,272 study participants, the mean PCS score was 49 (standard deviation (SD) 10.3). Participants were followed-up for a mean of 7.6 years. On survival analysis the lowest quintile of PCS was a strong predictor of all-cause death (hazard ratio (HR) 2.81, 95% CI 1.76, 4.49), incident cancer (HR 1.63, 95% CI 1.10, 2.42), and CHD events (HR 1.99, 95% CI 1.00, 3.96), compared to the highest quintile. This association was independent of adiposity and other confounders. The mean MCS score 52 (SD 8.8). MCS quintile was not associated with incident cancer and CHD, and the association between MCS and all-cause death (HR 1.33, 95% CI 1.01, 1.75) became non-significant after adjustment for adiposity.

Conclusion

Physical HRQoL is a significant predictor of a range of adverse outcomes, even after adjustment for adiposity and other confounders. This study highlights the importance of perceived health in the general population.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2458-14-1197) contains supplementary material, which is available to authorized users.

Gender differences in the association between adiposity and probable major depression: a cross-sectional study of 140,564 UK Biobank participants

BACKGROUND

Previous studies on the association between adiposity and mood disorder have produced contradictory results, and few have used measurements other than body mass index (BMI). We examined the association between probable major depression and several measurements of adiposity: BMI, waist circumference (WC), waist-hip-ratio (WHR), and body fat percentage (BF%).

METHODS

We conducted a cross-sectional study using baseline data on the sub-group of UK Biobank participants who were assessed for mood disorder. Multivariate logistic regression models were used, adjusting for potential confounders including: demographic and life-style factors, comorbidity and psychotropic medication.

RESULTS

Of the 140,564 eligible participants, evidence of probable major depression was reported by 30,145 (21.5%). The fully adjusted odds ratios (OR) for obese participants were 1.16 (95% confidence interval (CI) 1.12, 1.20) using BMI, 1.15 (95% CI 1.11, 1.19) using WC, 1.09 (95% CI 1.05, 1.13) using WHR and 1.18 (95% CI 1.12, 1.25) using BF% (all p < 0.001). There was a significant interaction between adiposity and gender (p = 0.001). Overweight women were at increased risk of depression with a dose response relationship across the overweight (25.0-29.9 kg/m2), obese I (30.0-34.9 kg/m2), II (35.0-39.9 kg/m2) and III (≥40.0 kg/m2) categories; fully adjusted ORs 1.14, 1.20, 1.29 and 1.48, respectively (all p < 0.001). In contrast, only obese III men had significantly increased risk of depression (OR 1.29, 95% CI 1.08, 1.54, p = 0.006).

CONCLUSION

Adiposity was associated with probable major depression, irrespective of the measurement used. The association was stronger in women than men. Physicians managing overweight and obese women should be alert to this increased risk.

Association between self-reported general and mental health and adverse outcomes: a retrospective cohort study of 19,625 Scottish adults

OBJECTIVE

Self-reported general health and mental health are independent predictors of all-cause mortality. This study examines whether they are also independent predictors of incident cancer, coronary heart disease and psychiatric hospitalisation.

METHODS

We conducted a retrospective, population cohort study by linking the 19 625 Scottish adults who participated in the Scottish Health Surveys 1995-2003, to hospital admissions, cancer registration and death certificate records. We conducted Cox proportional hazard models adjusting for potential confounders including age, sex, socioeconomic status, alcohol, smoking status, body mass index, hypertension and diabetes.

RESULTS

Poor general health was reported by 1215 (6.2%) participants and was associated with cancer registrations (adjusted Hazard Ratio [HR] 1.30, 95% CI 1.10, 1.55), coronary heart disease events (adjusted HR 2.30, 95% CI 1.86, 2.84) and psychiatric hospitalisations (adjusted HR 2.42, 95% CI 1.65, 3.56). There was evidence of dose relationships and the associations remained significant after adjustment for mental health. 3172 (16%) participants had poor mental health (GHQ ≥ 4). After adjustment for general health, the associations between poor mental health and coronary heart disease events (adjusted HR 1.36, 95% CI 1.13, 1.63) and all-cause death (adjusted HR 1.38, 95% CI 1.23, 1.55) became non-significant, but mental health remained associated with psychiatric hospitalisations (fully adjusted HR 2.02, 95% CI 1.48, 2.75).

CONCLUSION

Self-reported general health is a significant predictor of a range of clinical outcomes independent of mental health. The association between mental health and non-psychiatric outcomes is mediated by general health but it is an independent predictor of psychiatric outcome. Individuals with poor general health or mental health warrant close attention.

Heaviness, health and happiness: a cross-sectional study of 163066 UK Biobank participants

BACKGROUND

Obesity is known to increase the risk of many diseases and reduce overall quality of life. This study examines the relationship with self-reported health (SRH) and happiness.

METHODS

We conducted a cross-sectional study of the 163 066 UK Biobank participants who completed the happiness rating. The association between adiposity and SRH and happiness was examined using logistic regression. SRH was defined as good (excellent, good), or poor (fair, poor). Self-reported happiness was defined as happy (extremely, very, moderately) or unhappy (moderately, very, extremely).

RESULTS

Poor health was reported by 44 457 (27.3%) participants. The adjusted ORs for poor health were 3.86, 2.92, 2.60 and 6.41 for the highest, compared with lowest, deciles of Body Mass Index, waist circumference, waist to hip ratio and body fat percent, respectively. The associations were stronger in men (p<0.001). Overall, 7511 (4.6%) participants felt unhappy, and only class III obese participants were more likely to feel unhappy (adjusted OR 1.33, 95% CI 1.15 to 1.53, p<0.001) but the associations differed by sex (p<0.001). Among women, there was a significant association between unhappiness and all levels of obesity. By contrast, only class III obese men had significantly increased risk and overweight and class I obese men were less likely to be unhappy.

CONCLUSIONS

Obesity impacts adversely on happiness as well as health, but the association with unhappiness disappeared after adjustment for self-reported health, indicating this may be mediated by health. Compared with obese men, obese women are less likely to report poor health, but more likely to feel unhappy.