Increasing obesity in adults with mobility disability has become a considerable health problem, similar to the increasing trend of obesity in the general population. The aims of this study were to investigate the association of mobility disability with overweight status and obesity in a large population-based Swedish cohort of adults, and to investigate whether mobility disability, high body mass index (BMI), and increasing BMI over time are predictors of health-related quality of life and participation in society after 8 years of follow-up.
The study cohort included 13,549 individuals aged 18–64 years who answered questions about mobility disability, weight, height, health-related quality of life and participation in society in the Stockholm Public Health Survey 2002 and 2010. The cohort was randomly selected from the population of Stockholm County, and divided into six subgroups based on data for mobility disability and overweight status. Multiple binary logistic regression analyses were performed to assess the likelihood for low health-related quality of life and lack of participation.
Respondents with mobility disability had a higher mean BMI than those without mobility disability. Respondents both with and without mobility disability increased in BMI, but with no significant difference in the longitudinal changes (mean difference: 0.078; 95% CI: -0.16 - 0.32). Presence of mobility disability increased the risk of low health-related quality of life and lack of participation in 2010, irrespective of low health-related quality of life and lack of participation in 2002. The risk of pain and low general health (parts of health-related quality of life) increased for every 5 units of higher BMI reported in 2010. In respondents without low general health at baseline, the risk of obtaining low general health increased for every 5 units of higher BMI in 2010 (OR:1.60; CI: 1.47 - 1.74).
The greatest risk of low general health after 8 years was observed for respondents with both mobility disability and high BMI. These results indicate the importance of working preventively with persons with mobility disability and overweight status or obesity based on the risk of further weight gain.
Mobility disability; Overweight; Obesity; Prevalence; Population study; Health-related quality of life (HRQoL); Participation
Childhood obesity is a growing concern in Sweden. Children with overweight and obesity run a high risk of becoming obese as adults, and are likely to develop comorbidities. Despite the immense demand, there is still a lack of evidence-based comprehensive prevention programmes targeting pre-school children and their families in primary health care settings. The aims are to describe the design and methodology of the PRIMROSE cluster-randomised controlled trial, assess the relative validity of a food frequency questionnaire, and describe the baseline characteristics of the eligible young children and their mothers.
The PRIMROSE trial targets first-time parents and their children at Swedish child health centres (CHC) in eight counties in Sweden. Randomisation is conducted at the CHC unit level. CHC nurses employed at the participating CHC received training in carrying out the intervention alongside their provision of regular services. The intervention programme, starting when the child is 8-9 months of age and ending at age 4, is based on social cognitive theory and employs motivational interviewing. Primary outcomes are children’s body mass index and waist circumference at four years. Secondary outcomes are children’s and mothers’ eating habits (assessed by a food frequency questionnaire), and children’s and mothers’ physical activity (measured by accelerometer and a validated questionnaire), and mothers’ body mass index and waist circumference.
The on-going population-based PRIMROSE trial, which targets childhood obesity, is embedded in the regular national (routine) preventive child health services that are available free-of-charge to all young families in Sweden. Of the participants (n = 1369), 489 intervention and 550 control mothers (75.9%) responded to the validated physical activity and food frequency questionnaire at baseline (i.e., before the first intervention session, or, for children in the control group, before they reached 10 months of age). The food frequency questionnaire showed acceptable relative validity when compared with an 8-day food diary. We are not aware of any previous RCT, concerned with the primary prevention of childhood obesity through sessions at CHC that addresses healthy eating habits and physical activity in the context of a routine child health services programme.
Childhood obesity; Primary prevention; Motivational interviewing; Primary care setting; Intervention study
According to the fetal overnutrition hypothesis, obesity in pregnancy predisposes the offspring to obesity. Previous studies have suggested that after biliopancreatic surgery for obesity, the offspring is less likely to be obese. This study aims to further compare the BMI development of children born before and after maternal surgical weight loss.
Women with at least one child born before and one child born after bariatric surgery were identified by record-linkage. Information about maternal BMI was extracted from medical records, as was information about the children's BMI from birth to 10 years of age. We retrieved BMI data at four years of age for 340 children, born to 223 women (164 children born before surgery (BS), 176 children born after surgery (AS)). We evaluated prevalence of overweight/obesity and mean BMI in children born BS and AS at the ages of four, six and ten using GEE regression models. For 71 families, where we had complete data on mother and both children, we used a fixed-effects regression model to explore the association between differences in maternal BMI in w10 of the pre- and post-operative pregnancies with siblings' BMI differences at age four.
In no age group did we see a significantly reduced prevalence of overweight/obesity AS. For 10-year-old girls, the AS group had significantly higher rates of obesity. There was no association between differences in maternal BMI in early pregnancy and differences in siblings' BMI at four years of age (β = −0.01, CI 95% = −0.11; 0.09).
We have been unable to demonstrate any effect of bariatric surgery on weight development in offspring. It seems unlikely that restrictive bariatric surgery conveys a protective effect in offspring with regards to obesity.
Anecdotal and biographical reports have long suggested that bipolar disorder is more common in people with exceptional cognitive or creative ability. Epidemiological evidence for such a link is sparse. We investigated the relationship between intelligence and subsequent risk of hospitalisation for bipolar disorder in a prospective cohort study of 1,049,607 Swedish men. Intelligence was measured on conscription for military service at a mean age of 18.3 years and data on psychiatric hospital admissions over a mean follow-up period of 22.6 years was obtained from national records. Risk of hospitalization with any form of bipolar disorder fell in a stepwise manner as intelligence increased (p for linear trend <0.0001). However, when we restricted analyses to men with no psychiatric comorbidity, there was a ‘reversed-J’ shaped association: men with the lowest intelligence had the greatest risk of being admitted with pure bipolar disorder, but risk was also elevated among men with the highest intelligence (p for quadratic trend = 0.03), primarily in those with the highest verbal (p for quadratic trend=0.009) or technical ability (p for quadratic trend <0.0001). At least in men, high intelligence may indeed be a risk factor for bipolar disorder, but only in the minority of cases who have the disorder in a pure form with no psychiatric comorbidity.
► Associations of exposures with mortality may be confounded by existing ill health. ► We used a son's height as an instrument for parents’ height to avoid confounding. ► Parents of taller sons had lower cardiovascular and respiratory disease mortality. ► Parents of taller sons had higher mortality from cancer. ► Previous studies of height are not substantially confounded by existing ill health.
Height is associated with mortality from many diseases, but it remains unclear whether the association is causal or due to confounding by social factors, genetic pleiotropy,1 or existing ill-health. The authors investigated whether the association of height with mortality is causal by using a son's height as an instrumental variable (IV) for parents’ height among the parents of a cohort of 1,036,963 Swedish men born between 1951 and 1980 who had their height measured at military conscription, aged around 18, between 1969 and 2001. In a two-sample IV analysis adjusting for son's age at examination and secular trends in height, as well as parental age, and socioeconomic position, the hazard ratio (HR) for all-cause paternal mortality per standard deviation (SD, 6.49 cm) of height was 0.96 (95% confidence interval (CI): 0.95, 0.96). The results of IV analyses of mortality from all causes, cardiovascular disease (CVD), respiratory disease, cancer, external causes and suicide were comparable to those obtained using son's height as a simple proxy for own height and to conventional analyses of own height in the present data and elsewhere, suggesting that such conventional analyses are not substantially confounded by existing ill-health.
IV, instrumental variable; HR, hazard ratio; SD, standard deviation; CI, confidence interval; CVD, cardiovascular disease; BMI, body mass index; SEP, socioeconomic position; CHD, coronary heart disease; Body height; Mortality; Confounding factor; Causality; Cohort studies
Birth order has been suggested to be linked to several cardiovascular disease (CVD) risk factors, but the evidence is still inconsistent. We aim to determine the associations of birth order with body mass index (BMI), muscle strength and blood pressure. Further we will analyse whether these relationships are affected by family characteristics.
BMI, elbow flexion, hand grip and knee extension strength and systolic and diastolic blood pressure were measured at conscription examination in 1 065 710 Swedish young men born between 1951 and 1975. The data were analysed using linear multivariate and fixed effects regression models; the latter compare siblings and account for genetic and social factors shared by brothers.
Fixed effect regression analysis showed that birth order was inversely associated with BMI: second and third born had 0.8% and 1.1% (p<0.001) lower BMI than first-born, respectively. The association pattern differed among muscle strengths. After adjustment for BMI, first-born presented lower elbow flexion and hand grip strength than second-born (−5.9 N and −3.8 N, respectively, p<0.001). Knee extension strength was inversely related to birth order though not always significantly. The association between birth order and blood pressure was not significant.
Birth order is negatively associated with BMI and knee extension strength, positively with elbow flexion and hand grip strength, and is not associated with blood pressure among young men. Although the effects are small, the link between birth order and some CVD risk factors is already detectable in young adulthood.
Research on the temporal relationship of parental risk factors with offspring’s suicide attempt is scarce and a life course approach has not been applied to date. We investigated the temporal relationship of parental morbidity and mortality with offspring’s suicide attempt and whether any such association was modified by offspring’s age at attempt.
We designed a case-control study through linkage of Swedish registers. Cases comprised all individuals in Sweden born 1973–1983 with inpatient care due to suicide attempt (15–31 years of age) and with information on both biological parents (N = 15 193). Ten controls were matched to each case (National Patient register with national complete coverage). Conditional logistic and spline regressions were applied.
Particularly for women, most parental markers showed the strongest effect sizes if exposure was short-term (within 2 years after exposure) and related to the mother. Especially short-term exposure to maternal inpatient care due to psychiatric diagnoses had a significantly stronger effect on suicide attempt risk in women compared to men. Regarding exposure to parental inpatient care due to psychiatric diagnoses, short-term as opposed to long-term (exceeding 2 years after exposure) effects were highest during adolescence and decreased significantly with age for female and male offspring, respectively.
Although limited by the fact that data on parental morbidity and the outcome of suicidality were based on in-patient data only, the data suggest that the high risks of suicide attempt in case of exposure to parental psychopathology and suicidal behavior particularly during adolescence and the strong short-term effects associated with maternal psychopathology for female offspring are of direct clinical importance.
Patients admitted to hospital with acute respiratory symptoms remain a diagnostic challenge for the emergency physician. The use of focused sonography may improve the initial diagnostics, as most of the diseases, commonly seen and misdiagnosed in patients with acute respiratory symptoms, can be diagnosed with sonography. The protocol describes a prospective, blinded, randomised controlled trial that aims to assess the diagnostic impact of a pragmatic implementation of focused sonography of the heart, lungs and deep veins as a diagnostic modality in acute admitted patients with respiratory symptoms.
Methods and analysis
The primary outcome of the study is the number of patients with a correct presumptive diagnosis within 4 h of admission to the emergency department. The patient is randomised to either an intervention or a control group. In the intervention group, the usual initial diagnostic work up is supplemented by focused sonographic examination of the heart, lungs and deep veins of the legs. In the control group, usual diagnostic work up is performed. The χ2 test, alternatively the Fischer exact test will be used, to establish whether there is a difference in the distribution of the total number of patients with a correct/incorrect ‘4 h’ presumptive diagnosis in the control group and in the intervention group.
Ethics and dissemination
This clinical trial is performed according to the Declaration of Helsinki and has been approved by the Regional Scientific Ethical Committee for Southern Denmark and the Danish Data Protection Agency. The results of the trial will be published according to the CONSORT statement with the extension for pragmatic trials. The results of the trial will be published in a peer-reviewed scientific journal regardless of the outcome.
Trial registration number
This study is registered at http://clinicaltrials.gov, registration number NCT01486394.
Focused sonography of the heart, lungs and deep veins.
Initial diagnostics of acute admitted patients with respiratory symptoms.
The results of the study may help to determine whether sonography should be included as a fully integrated part of the primary evaluation in these patients.
Strengths and limitations of this study
First randomised trial to compare the overall diagnostic performance between the conventional approach and an approach including focused sonography to evaluate and diagnose acute admitted patients with respiratory symptoms, admitted to an emergency department.
Pragmatic design with inclusion of most patients with respiratory symptoms.
Single-centre study that could affect external validity.
Study not powered to investigate morbidity or mortality.
To examine the genetic and environmental influences on variances in weight, height, and BMI, from birth through 19 years of age, in boys and girls from three continents.
Design and Settings
Cross-sectional twin study. Data obtained from a total of 23 twin birth-cohorts from four countries: Canada, Sweden, Denmark, and Australia. Participants were Monozygotic (MZ) and dizygotic (DZ) (same- and opposite-sex) twin pairs with data available for both height and weight at a given age, from birth through 19 years of age. Approximately 24,036 children were included in the analyses.
Heritability for body weight, height, and BMI was low at birth (between 6.4 and 8.7% for boys, and between 4.8 and 7.9% for girls) but increased over time, accounting for close to half or more of the variance in body weight and BMI after 5 months of age in both sexes. Common environmental influences on all body measures were high at birth (between 74.1–85.9% in all measures for boys, and between 74.2 and 87.3% in all measures for girls) and markedly reduced over time. For body height, the effect of the common environment remained significant for a longer period during early childhood (up through 12 years of age). Sex-limitation of genetic and shared environmental effects was observed.
Genetics appear to play an increasingly important role in explaining the variation in weight, height, and BMI from early childhood to late adolescence, particularly in boys. Common environmental factors exert their strongest and most independent influence specifically in pre-adolescent years and more significantly in girls. These findings emphasize the need to target family and social environmental interventions in early childhood years, especially for females. As gene-environment correlation and interaction is likely, it is also necessary to identify the genetic variants that may predispose individuals to obesity.
A link between low parental socioeconomic status and mental health problems in offspring is well established in previous research. The mechanisms that explain this link are largely unknown. The present study investigated whether school performance was a mediating and/or moderating factor in the path between parental socioeconomic status and the risk of hospital admission for non-fatal suicidal behaviour.
A national cohort of 447 929 children born during 1973-1977 was followed prospectively in the National Patient Discharge Register from the end of their ninth and final year of compulsory school until 2001. Multivariate Cox proportional hazards and linear regression analyses were performed to test whether the association between parental socioeconomic status and non-fatal suicidal behaviour was mediated or moderated by school performance.
The results of a series of multiple regression analyses, adjusted for demographic variables, revealed that school performance was as an important mediator in the relationship between parental socioeconomic status and risk of non-fatal suicidal behaviour, accounting for 60% of the variance. The hypothesized moderation of parental socioeconomic status-non-fatal suicidal behaviour relationship by school performance was not supported.
School performance is an important mediator through which parental socioeconomic status translates into a risk for non-fatal suicidal behaviour. Prevention efforts aimed to reduce socioeconomic inequalities in non-fatal suicidal behaviour among young people will need to consider socioeconomic inequalities in school performance.
Non-fatal suicidal behaviour; Socioeconomic status; School performance; Cohort studies
Background and Objectives
There is no doubt that the dramatic worldwide increase in obesity prevalence is due to changes in environmental factors. However, twin and family studies suggest that genetic differences are responsible for the major part of the variation in adiposity within populations. Recent studies show that the genetic effects on body mass index (BMI) may be stronger when combined with presumed risk factors for obesity. We tested the hypothesis that the genetic variance of BMI has increased during the obesity epidemic.
The data comprised height and weight measurements of 1,474,065 Swedish conscripts at age 18–19 y born between 1951 and 1983. The data were linked to the Swedish Multi-Generation Register and the Swedish Twin Register from which 264,796 full-brother pairs, 1,736 monozygotic (MZ) and 1,961 dizygotic (DZ) twin pairs were identified. The twin pairs were analysed to identify the most parsimonious model for the genetic and environmental contribution to BMI variance. The full-brother pairs were subsequently divided into subgroups by year of birth to investigate trends in the genetic variance of BMI.
The twin analysis showed that BMI variation could be explained by additive genetic and environmental factors not shared by co-twins. On the basis of the analyses of the full-siblings, the additive genetic variance of BMI increased from 4.3 [95% CI 4.04–4.53] to 7.9 [95% CI 7.28–8.54] within the study period, as did the unique environmental variance, which increased from 1.4 [95% CI 1.32–1.48] to 2.0 [95% CI 1.89–2.22]. The BMI heritability increased from 75% to 78.8%.
The results confirm the hypothesis that the additive genetic variance of BMI has increased strongly during the obesity epidemic. This suggests that the obesogenic environment has enhanced the influence of adiposity related genes.
Associations between body mass index (BMI) and attempted (nonfatal) suicide have recently been reported. However, the few existing studies are relatively small in scale, the majority cross-sectional, and results contradictory. The authors have explored BMI–attempted suicide associations in a large cohort of 1,133,019 Swedish men born between 1950 and 1976, with BMI measured in early adulthood. During a mean follow-up of 23.9 years, a total of 18,277 (1.6%) men had at least 1 hospital admission for attempted suicide. After adjustment for confounding factors, there was a stepwise, linear decrease in attempted suicide with increasing BMI across the full BMI range (per standard deviation increase in BMI, hazard ratio = 0.93, 95% confidence interval: 0.91, 0.94). Analyses excluding men with depression at baseline were essentially identical to those based on the complete cohort. In men free from depression at baseline, controlling for subsequent depression slightly attenuated the raised risk of attempted suicide, particularly in lower weight men. This study suggests that lower weight men have an increased risk of attempted suicide and that associations may extend into the “normal” BMI range.
body mass index; cohort studies; depression; social class; suicide, attempted
We applied twin methodology to female and male twin pairs to further understand the nature of the relation between two behaviors associated with eating disorders—binge eating (BE) and night eating (NE) in an effort to determine the extent of overlap of genetic and environmental factors influencing liability to these behaviors. We calculated heritability estimates for males and females for each behavior and applied bivariate twin modeling to the female data to estimate the genetic and environmental correlation between these two traits. Data on BE and NE were derived from the Swedish Twin Study of Adults: Genes and Environment (STAGE) of the Swedish Twin Registry (STR; N = 11604). Prevalence estimates revealed sex differences with females more likely to endorse BE and males more likely to endorse NE. In males, we were only able to estimate univariate heritabilities due to small sample sizes: The heritability for BE was .74 [95% CI = (0.36, 0.93)] and for NE was .44 [95% CI = (0.24, 0.61)]. The best fitting bivariate model for females included additive genetic and unique environmental factors as well as the genetic correlation between BE and NE. Heritability estimates were 0.70 [95% CI = (0.26, 0.77)] for BE and 0.35 [95% CI = (0.17, 0.52)] for NE. The genetic correlation, 0.66 [95% CI = (0.48, 0.96)] suggests considerable overlap in the genetic factors influencing liability to BE and NE. In females, there is considerable overlap in the genetic factors that contribute to these traits, but the incomplete overlap allows for the influence of independent genetic and environmental factors as well. BE and NE in females are therefore best conceptualized as related but not identical traits.
Objective To investigate the nature and magnitude of relations of systolic and diastolic blood pressures in late adolescence to mortality.
Design Nationwide cohort study.
Setting General community in Sweden.
Participants Swedish men (n=1 207 141) who had military conscription examinations between 1969 and 1995 at a mean age of 18.4 years, followed up for a median of 24 (range 0-37) years.
Main outcome measures Total mortality, cardiovascular mortality, and non-cardiovascular mortality.
Results During follow-up, 28 934 (2.4%) men died. The relation of systolic blood pressure to total mortality was U shaped, with the lowest risk at a systolic blood pressure of about 130 mm Hg. This pattern was driven by the relation to non-cardiovascular mortality, whereas the relation to cardiovascular mortality was monotonically increasing (higher risk with higher blood pressure). The relation of diastolic blood pressure to mortality risk was monotonically increasing and stronger than that of systolic blood pressure, in terms of both relative risk and population attributable fraction (deaths that could be avoided if blood pressure was in the optimal range). Relations to cardiovascular and non-cardiovascular mortality were similar, with an apparent risk threshold at a diastolic blood pressure of about 90 mm Hg, below which diastolic blood pressure and mortality were unrelated, and above which risk increased steeply with higher diastolic blood pressures.
Conclusions In adolescent men, the relation of diastolic blood pressure to mortality was more consistent than that of systolic blood pressure. Considering current efforts for earlier detection and prevention of risk, these observations emphasise the risk associated with high diastolic blood pressure in young adulthood.
Primary health care specialists have a key role in the management of obesity. Through understanding how they conceive the encounter with patients with obesity, treatment may be improved. The aim of this study was thus to explore general practitioners' and district nurses' conceptions of encountering patients with obesity in primary health care.
Data were collected through semi-structured interviews, and analysed using a phenomenographic approach. The participants were 10 general practitioners (6 women, 4 men) and 10 district nurses (7 women, 3 men) from 19 primary health care centres within a well-defined area of Sweden.
Five descriptive categories were identified: Adequate primary health care, Promoting lifestyle change, Need for competency, Adherence to new habits and Understanding patient attitudes. All participants, independent of gender and profession, were represented in the descriptive categories. Some profession and gender differences were, however, found in the underlying conceptions. The general staff view was that obesity had to be prioritised. However, there was also the contradictory view that obesity is not a disease and therefore not the responsibility of primary health care. Despite this, staff conceived it as important that patients were met with respect and that individual solutions were provided which could be adhered to step-by-step by the patient. Patient attitudes, such as motivation to change, evasive behaviour, too much trust in care and lack of self-confidence, were, however, conceived as major barriers to a fruitful encounter.
Findings from this study indicate that there is a need for development and organisation of weight management in primary health care. Raising awareness of staff's negative views of patient attitudes is important since it is likely that it affects the patient-staff relationship and staff's treatment efforts. More research is also needed on gender and profession differences in this area.
Grip strength, walking speed, chair rising and standing balance time are objective measures of physical capability that characterise current health and predict survival in older populations. Socioeconomic position (SEP) in childhood may influence the peak level of physical capability achieved in early adulthood, thereby affecting levels in later adulthood. We have undertaken a systematic review with meta-analyses to test the hypothesis that adverse childhood SEP is associated with lower levels of objectively measured physical capability in adulthood.
Methods and Findings
Relevant studies published by May 2010 were identified through literature searches using EMBASE and MEDLINE. Unpublished results were obtained from study investigators. Results were provided by all study investigators in a standard format and pooled using random-effects meta-analyses. 19 studies were included in the review. Total sample sizes in meta-analyses ranged from N = 17,215 for chair rise time to N = 1,061,855 for grip strength. Although heterogeneity was detected, there was consistent evidence in age adjusted models that lower childhood SEP was associated with modest reductions in physical capability levels in adulthood: comparing the lowest with the highest childhood SEP there was a reduction in grip strength of 0.13 standard deviations (95% CI: 0.06, 0.21), a reduction in mean walking speed of 0.07 m/s (0.05, 0.10), an increase in mean chair rise time of 6% (4%, 8%) and an odds ratio of an inability to balance for 5s of 1.26 (1.02, 1.55). Adjustment for the potential mediating factors, adult SEP and body size attenuated associations greatly. However, despite this attenuation, for walking speed and chair rise time, there was still evidence of moderate associations.
Policies targeting socioeconomic inequalities in childhood may have additional benefits in promoting the maintenance of independence in later life.
Impaired lung function is associated with systemic inflammation and is a risk factor for cardiovascular disease in older adults. It is unknown when these associations emerge and to what extent they are mediated by smoking, chronic airways disease, and/or established atherosclerosis. We explored the association between the forced expiratory volume in one second (FEV1) and the systemic inflammatory marker C‐reactive protein (CRP) in young adults.
Associations between spirometric lung function and blood CRP were assessed in a population based birth cohort of approximately 1000 New Zealanders at ages 26 and 32 years. Analyses adjusted for height and sex to account for differences in predicted lung function and excluded pregnant women.
There were significant inverse associations between FEV1 and CRP at both ages. Similar results were found for the forced vital capacity. These associations were similar in men and women and were independent of smoking, asthma, and body mass index.
Reduced lung function is associated with systemic inflammation in young adults. This association is not related to smoking, asthma, or obesity. The reasons for the association are unexplained, but the findings indicate that the association between lower lung function and increased inflammation predates the development of either chronic lung disease or clinically significant atherosclerosis. The association between poor lung function and cardiovascular disease may be mediated by an inflammatory mechanism.
inflammation; C‐reactive protein; spirometry; cohort studies
Educational attainment, the highest degree or level of schooling obtained, is associated with important life outcomes, at both the individual level and the group level. Because of this, and because education is expensive, the allocation of education across society is an important social issue. A dynamic quantitative environmental-genetic model can help document the effects of social allocation patterns. We used this model to compare the moderating effect of general intelligence on the environmental and genetic factors that influence educational attainment in Sweden and the U.S. state of Minnesota. Patterns of genetic influence on educational outcomes were similar in these two regions, but patterns of shared environmental influence differed markedly. In Sweden, shared environmental influence on educational attainment was particularly important for people of high intelligence, whereas in Minnesota, shared environmental influences on educational attainment were particularly important for people of low intelligence. This difference may be the result of differing access to education: state-supported access (on the basis of ability) to a uniform higher-education system in Sweden, versus family-supported access to a more diverse higher-education system in the United States.
educational attainment; intelligence; gene-environment interaction; gene-environment correlation; genetic and environmental influences
The aim of this study was to assess the prevalence of night eating (NE) and associated symptoms in a population-based sample of Swedish twins. A total of 21,741 individuals aged 20-47 years completed a questionnaire in 2005/2006. NE was defined as ≥25% of daily food intake after the evening meal and/or awakening at least once per week with eating episodes. The prevalence of NE was 4.6% in men and 3.4% in women. Among obese men and women, the prevalence was 8.4% and 7.5%, respectively. Men and women with NE had 3.4 and 3.6 times higher risk of binge eating compared to individuals without NE. The risk of sleep-related problems was 1.6-3.4 times higher in men and 2.5-3.3 times higher in women with NE compared to those without NE. This epidemiological study has estimated the prevalence of NE in a twin population. It revealed that NE is 2.5 and 2.8 times more common in obese men and women compared to normal weight men and women. Furthermore that NE is associated with binge eating and sleep-related problems.
Night eating; binge eating; sleep problems; obesity; epidemiology; twins
Objectives To explore associations between IQ measured in early adulthood and subsequent hospital admissions for attempted suicide and to explore the role of psychosis and examine associations of IQ with specific methods of attempted suicide.
Design Cohort study.
Participants 1 109 475 Swedish men with IQ measured in early adulthood followed up for an average 24 years.
Main outcome measures Hospital admission for attempted suicide.
Results 17 736 (1.6%) men had at least one hospital admission for attempted suicide by any means during follow-up. After adjustment for age and socioeconomic status, lower IQ scores were associated with an elevated risk of attempted suicide by any means (hazard ratio per standard deviation decrease in IQ=1.57, 95% confidence interval 1.54 to 1.60), with stepwise increases in risk across the full IQ range (P for trend<0.001). Similar associations were observed for all specific methods of attempted suicide. Separate analyses indicated that associations between IQ and attempted suicide were restricted to participants without psychosis and that IQ had no marked impact on risk of attempted suicide in those with psychosis.
Conclusions Low IQ scores in early adulthood were associated with a subsequently increased risk of attempted suicide in men free from psychosis. A greater understanding of the mechanisms underlying these associations may provide opportunities and strategies for prevention.
Background and aim:
The general practitioner (GP) is the first contact with the health care system for most patients with COPD in Denmark. We studied, if participating in an educational program could improve adherence to guidelines, not least for diagnosis, staging, and treatment of the disease.
Design and setting:
Two cross-sectional surveys were performed precisely one year apart before and after an educational program for the participating GPs. A total of 124 GPs completed the study; 1716 and 1342 patients with GP-diagnosed COPD and no concomitant asthma, respectively, were included in the two surveys.
The proportion of patients having FEV1 registered in the GPs files increased from 45% to 69% (P < 0.001); and, furthermore, FEV1 % of predicted was recorded in 30% and 56%, respectively, of the cases (P < 0.001). In line with this, significant improvements were also observed for registration of smoking status (69% to 85%), BMI (8% to 40%), severity of dyspnea (Medical Research Council) (7% to 38%), and FEV1/FVC ratio (28% to 58%) (P < 0.001). Concerning the management options, improvements were also observed with regard to antismoking counseling, inhalator technique, physical activity, and referral for rehabilitation; use of inhaled corticosteroids in patients with mild COPD (FEV1 > 80%pred) declined from 76% to 45%.
Diagnosis and management of COPD in general practice in Denmark is not according to guidelines, but substantial improvements can be achieved by focused education of GPs and their staff.
COPD; guidelines; adherence; education; diagnosis; management
Objectives To obtain valid estimates of the association between body mass index (BMI) and mortality by using offspring BMI as an instrumental variable for own BMI.
Design Cohort study based on record linkage, with 50 years of follow-up for mortality. Associations of offspring BMI with all cause and cause specific maternal and paternal mortality were estimated as hazard ratios per standard deviation of offspring BMI.
Setting A large intergenerational prospective population based database covering the general population of Sweden.
Participants More than one million Swedish parent-son pairs.
Results The final dataset analysed contained information on 1 018 012 mother-son pairs (122 677 maternal deaths) and 1 004 617 father-son pairs (242 126 paternal deaths). For some causes of death, the patterns of associations between offspring BMI and mortality were similar to those seen for own BMI and mortality in previous studies. Parental mortality from diabetes, coronary heart disease, and kidney cancer had the strongest positive associations with offspring BMI (for example, hazard ratio (HR) for coronary heart disease per standard deviation increase in offspring BMI for mothers 1.15, 95% CI 1.14 to 1.17 and for fathers 1.10, 1.09 to 1.11). However, in contrast to the inverse association of own BMI with lung cancer and respiratory disease mortality seen in other studies, there was a positive association between offspring BMI and lung cancer mortality in mothers (1.12, 1.09 to 1.15) and fathers (1.03, 1.02 to 1.05) and between offspring BMI and respiratory mortality in mothers (1.05, 1.02 to 1.08) and fathers (1.02, 1.00 to 1.04). Associations of own BMI and offspring BMI with all cause, cardiovascular disease related, and non-cardiovascular disease related mortality were compared in a subset of father-son pairs (n=72 815). When offspring BMI was used as an instrumental variable for paternal BMI, the causal association between BMI and paternal cardiovascular disease mortality (HR per standard deviation of BMI 1.82, 95% CI 1.17 to 2.83) was stronger than that indicated by the directly observed association between own BMI and cardiovascular disease mortality (1.45, 1.31 to 1.61).
Conclusions Use of offspring BMI as a predictor of own BMI, a technique that avoids problems of reverse causality, suggests that positive associations of BMI with all cause and cardiovascular mortality may be underestimated in conventional observational studies. Use of offspring BMI instead of own BMI in analyses of respiratory disease and lung cancer mortality, for which previous studies have reported consistent and strong inverse associations with own BMI, suggests that such studies have overstated the apparent adverse consequences of lower BMI with respect to these outcomes.
Prenatal life exposures, potentially manifested as altered birth size, may influence the later risk of major chronic diseases through direct biologic effects on disease processes, but also by modifying adult behaviors such as physical activity that may influence later disease risk.
We investigated the association between birth weight and leisure time physical activity (LTPA) in 43,482 adolescents and adults from 13 Nordic cohorts. Random effects meta-analyses were performed on categorical estimates from cohort-, age-, sex- and birth weight specific analyses. Birth weight showed a reverse U-shaped association with later LTPA; within the range of normal weight the association was negligible but weights below and above this range were associated with a lower probability of undertaking LTPA. Compared with the reference category (3.26–3.75 kg), the birth weight categories of 1.26–1.75, 1.76–2.25, 2.26–2.75, and 4.76–5.25 kg, had odds ratios of 0.67 (95% confidence interval: 0.47, 0.94), 0.72 (0.59, 0.88), 0.89 (0.79, 0.99), and 0.65 (0.50, 0.86), respectively. The shape and strength of the birth weight-LTPA association was virtually independent of sex, age, gestational age, educational level, concurrent body mass index, and smoking.
The association between birth weight and undertaking LTPA is very weak within the normal birth weight range, but both low and high birth weights are associated with a lower probability of undertaking LTPA, which hence may be a mediator between prenatal influences and later disease risk.