Risk of future depression in people who are obese but metabolically healthy: the English longitudinal study of ageing

There is some evidence to suggest that obesity is a risk factor for the development of depression, although this is not a universal finding. This discordance might be ascribed to the existence of a 'healthy obese phenotype'--that is, obesity in the absence of the associated burden of cardiometabolic risk factors. We examined whether the association of obesity with depressive symptoms is dependent on the individual's metabolic health. Participants were 3851 men and women (aged 63.0±8.9 years, 45.1% men) from the English Longitudinal Study of Ageing, a prospective study of community dwelling older adults. Obesity was defined as body mass index ≥30 kg m(-2). Based on blood pressure, high-density lipoprotein cholesterol, triglycerides, glycated haemoglobin and C-reactive protein, participants were classified as 'metabolically healthy' (0 or 1 metabolic abnormality) or 'unhealthy' (≥2 metabolic abnormalities). Depressive symptoms were assessed at baseline and at 2 years follow-up using the 8-item Centre of Epidemiological Studies Depression (CES-D) scale. Obesity prevalence was 27.5%, but 34.3% of this group was categorized as metabolically healthy at baseline. Relative to non-obese healthy participants, after adjustment for baseline CES-D score and other covariates, the metabolically unhealthy obese participants had elevated risk of depressive symptoms at follow-up (odds ratio (OR)=1.50; 95% confidence interval (CI), 1.05-2.15), although the metabolically healthy obese did not (OR=1.38; 95% CI, 0.88-2.17). The association between obesity and risk of depressive symptoms appears to be partly dependent on metabolic health, although further work is required to confirm these findings.

Job strain in relation to body mass index: pooled analysis of 160 000 adults from 13 cohort studies

BACKGROUND

Evidence of an association between job strain and obesity is inconsistent, mostly limited to small-scale studies, and does not distinguish between categories of underweight or obesity subclasses.

OBJECTIVES

To examine the association between job strain and body mass index (BMI) in a large adult population.

METHODS

We performed a pooled cross-sectional analysis based on individual-level data from 13 European studies resulting in a total of 161 746 participants (49% men, mean age, 43.7 years). Longitudinal analysis with a median follow-up of 4 years was possible for four cohort studies (n = 42 222).

RESULTS

A total of 86 429 participants were of normal weight (BMI 18.5-24.9 kg m(-2) ), 2149 were underweight (BMI < 18.5 kg m(-2) ), 56 572 overweight (BMI 25.0-29.9 kg m(-2) ) and 13 523 class I (BMI 30-34.9 kg m(-2) ) and 3073 classes II/III (BMI ≥ 35 kg m(-2) ) obese. In addition, 27 010 (17%) participants reported job strain. In cross-sectional analyses, we found increased odds of job strain amongst underweight [odds ratio 1.12, 95% confidence interval (CI) 1.00-1.25], obese class I (odds ratio 1.07, 95% CI 1.02-1.12) and obese classes II/III participants (odds ratio 1.14, 95% CI 1.01-1.28) as compared with participants of normal weight. In longitudinal analysis, both weight gain and weight loss were related to the onset of job strain during follow-up.

CONCLUSIONS

In an analysis of European data, we found both weight gain and weight loss to be associated with the onset of job strain, consistent with a 'U'-shaped cross-sectional association between job strain and BMI. These associations were relatively modest; therefore, it is unlikely that intervention to reduce job strain would be effective in combating obesity at a population level.

Why the Scots die younger: synthesizing the evidence

OBJECTIVE

To identify explanations for the higher mortality in Scotland relative to other European countries, and to synthesize those best supported by evidence into an overall explanatory framework.

STUDY DESIGN

Review and dialectical synthesis.

METHODS

Candidate hypotheses were identified based on a literature review and a series of research dissemination events. Each hypothesis was described and critically evaluated in relation to the Bradford-Hill criteria for causation in observational epidemiology. A synthesis of the more convincing hypotheses was then attempted using a broadly 'dialectical' approach.

RESULTS

Seventeen hypotheses were identified including: artefactual explanations (deprivation, migration); 'downstream explanations' (genetics, health behaviours, individual values); 'midstream' explanations (substance misuse; culture of boundlessness and alienation; family, gender relations and parenting differences; lower social capital; sectarianism; culture of limited social mobility; health service supply or demand; deprivation concentration); and 'upstream' explanations (climate, inequalities, de-industrialization, political attack). There is little evidence available to determine why mortality rates diverged between Scotland and other European countries between 1950 and 1980, but the most plausible explanations at present link to particular industrial, employment, housing and cultural patterns. From 1980 onwards, the higher mortality has been driven by unfavourable health behaviours, and it seems quite likely that these are linked to an intensifying climate of conflict, injustice and disempowerment. This is best explained by developing a synthesis beginning from the political attack hypothesis, which suggests that the neoliberal policies implemented from 1979 onwards across the UK disproportionately affected the Scottish population.

CONCLUSIONS

The reasons for the high Scottish mortality between 1950 and 1980 are unclear, but may be linked to particular industrial, employment, housing and cultural patterns. From 1980 onwards, the higher mortality is most likely to be accounted for by a synthesis which begins from the changed political context of the 1980s, and the consequent hopelessness and community disruption experienced. This may have relevance to faltering health improvement in other countries, such as the USA.

Childhood socioeconomic position, adult socioeconomic position and social mobility in relation to markers of adiposity in early adulthood: evidence of differential effects by gender in the 1978/79 Ribeirao Preto cohort study

Background:

Longitudinal studies drawn from high-income countries demonstrate long-term associations of early childhood socioeconomic deprivation with increased adiposity in adulthood. However, there are very few data from resource-poor countries where there are reasons to anticipate different gradients. Accordingly, we sought to characterise the nature of the socioeconomic status (SES)-adiposity association in Brazil.

Methods:

We use data from the Ribeirao Preto Cohort Study in Brazil in which 9067 newborns were recruited via their mothers in 1978/79 and one-in-three followed up in 2002/04 (23–25years). SES, based on family income (salaries, interest on savings, pensions and so on), was assessed at birth and early adulthood, and three different adiposity measures (body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR)) ascertained at follow-up. The association between childhood SES, adult SES and social mobility (defined as four permutations of SES in childhood and adulthood: low–low, low–high, high–low, high–high), and the adiposity measures was examined using linear regression.

Results:

There was evidence that the association between SES and the three markers of adiposity was modified by gender in both adulthood (P<0.02 for all outcomes) and childhood SES (P<0.02 for WC and WHR). Thus, in an unadjusted model, linear regression analyses showed that higher childhood SES was associated with lower adiposity in women (coefficient (95% confidence intervals) BMI: −1.49 (−2.29,−0.69); WC: −3.85 (−5.73,−1.97); WHR: −0.03 (−0.04,−0.02)). However, in men, higher childhood SES was related to higher adiposity (BMI: 1.03 (0.28,−1.78); WC: 3.15 (1.20, 5.09); WHR: 0.009 (−0.001, 0.019)) although statistical significance was not seen in all analyses. There was a suggestion that adult SES (but not adult health behaviours or birthweight) accounted for these relationships in women only. Upward mobility was associated with protection against greater adiposity in women but not men.

Conclusion:

In the present study, in men there was some evidence that both higher childhood and adulthood SES was related to a higher adiposity risk, while the reverse gradient was apparent in women.

Resting heart rate and the risk of death and cardiovascular complications in patients with type 2 diabetes mellitus

AIMS/HYPOTHESIS

An association between resting heart rate and mortality has been described in the general population and in patients with cardiovascular disease. There are, however, few data exploring this relationship in patients with type 2 diabetes mellitus. The current study addresses this issue.

METHODS

The relationship between baseline resting heart rate and all-cause mortality, cardiovascular death and major cardiovascular events (cardiovascular death, non-fatal myocardial infarction or non-fatal stroke) was examined in 11,140 patients who participated in the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified Release Controlled Evaluation (ADVANCE) Study.

RESULTS

A higher resting heart rate was associated with a significantly increased risk of all-cause mortality (fully adjusted HR 1.15 per 10 bpm [95% CI 1.08, 1.21], p<0.001), cardiovascular death and major cardiovascular outcomes without adjustment and after adjusting for age and sex and multiple covariates. The increased risk associated with a higher baseline resting heart rate was most obvious in patients with previous macrovascular complications (fully adjusted HR for death 1.79 for upper [mean 91 bpm] vs lowest [mean 58 bpm] fifth of resting heart rate in this subgroup [95% CI 1.28, 2.50], p = .001).

CONCLUSIONS/INTERPRETATION

Among patients with type 2 diabetes, a higher resting heart rate is associated with an increased risk of death and cardiovascular complications. It remains unclear whether a higher heart rate directly mediates the increased risk or is a marker for other factors that determine a poor outcome.

Influence of maternal and paternal IQ on offspring health and health behaviours: evidence for some trans-generational associations using the 1958 British birth cohort study

PURPOSE

Individuals scoring poorly on tests of intelligence (IQ) have been reported as having increased risk of morbidity, premature mortality, and risk factors such as obesity, high blood pressure, poor diet, alcohol and cigarette consumption. Very little is known about the impact of parental IQ on the health and health behaviours of their offspring.

METHODS

We explored associations of maternal and paternal IQ scores with offspring television viewing, injuries, hospitalisations, long standing illness, height and BMI at ages 4 to 18 using data from the National Child Development Study (1958 birth cohort).

RESULTS

Data were available for 1446 mother-offspring and 822 father-offspring pairs. After adjusting for potential confounding/mediating factors, the children of higher IQ parents were less likely to watch TV (odds ratio (95% confidence interval) for watching 3+ vs. less than 3hours per week associated with a standard deviation increase in maternal or paternal IQ: 0.75 (0.64, 0.88) or 0.78 (0.64, 0.95) respectively) and less likely to have one or more injuries requiring hospitalisation (0.77 (0.66, 0.90) or 0.72 (0.56, 0.91) respectively for maternal or paternal IQ).

CONCLUSIONS

Children whose parents have low IQ scores may have poorer selected health and health behaviours. Health education might usefully be targeted at these families.

Sex hormones and cause-specific mortality in the male veterans: the Vietnam Experience Study

BACKGROUND

Testosterone levels have been linked to life expectancy in men, less is known about the sex hormones follicular stimulating hormone and luteinizing hormone.

AIM

To examine the association of testosterone, follicular stimulating hormone, luteinizing hormone with mortality.

DESIGN

Prospective cohort analysis.

METHODS

Participants were 4255 Vietnam-era US army veterans with a mean age of 38.3 years. From military service files, telephone interviews and a medical examination, socio-demographic and health data were collected. Contemporary morning fasted hormone concentrations were determined. All-cause, cardiovascular, cancer, external and 'other' cause mortality was ascertained over the subsequent 15 years. Hazard ratios were calculated, first with adjustment for age and then, additionally, for a range of confounders.

RESULTS

Individuals within the highest tertiles of follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels were at increased risk of all-cause mortality following adjustment for a range of risk factors. However, with mutual adjustment, neither FSH nor LH significantly predicted mortality. Testosterone levels did not show an association with all-cause mortality, and none of the hormones were significantly associated with CVD, cancer, 'other' or external-cause mortality in fully adjusted models.

CONCLUSION

Greater FSH and LH levels are associated with all-cause mortality, but not independently of one another.

Association of body mass index in early adulthood and middle age with future site-specific cancer mortality: the Harvard Alumni Health Study

BACKGROUND

The association between adiposity in early adulthood and subsequent development of specific malignancies is unclear. Further, the potential for mediation by adiposity in middle age has not been well examined. In a rare study, we investigated the association of body mass index (BMI) in early adulthood with mortality from several site-specific cancers.

DESIGN

In the Harvard Alumni Health Study cohort, 19 593 males had a physical examination at the university between 1914 and 1952 (mean age: 18.4 years) and returned a questionnaire in 1962 or 1966 (mean age = 45.1 years). BMI was computed using weight (kg)/height(2) (m(2)) at both time points. Vital status follow up continued for a maximum of 82 years.

RESULTS

Positive early adulthood cancer mortality gradients by BMI were found for all malignancies combined (adjusted hazard ratio [HR] = 1.11; 95% confidence interval [CI]: 1.05-1.17 for a one standard deviation increase in early adulthood BMI), and for lung (HR = 1.24; 95% CI = 1.10-1.40) and skin (HR = 1.29; 95% CI = 0.96-1.75) cancers. There were also apparent associations for cancers of the oesophagus and urogenital sites. Mediation by BMI in middle age was found to be minimal.

CONCLUSION

Higher BMI in early adulthood appears to be a direct risk factor for selected malignancies several decades later.

Body mass index, waist circumference and waist-hip ratio: which is the better discriminator of cardiovascular disease mortality risk?: evidence from an individual-participant meta-analysis of 82 864 participants from nine cohort studies

Few studies have examined both the relative magnitude of association and the discriminative capability of multiple indicators of obesity with cardiovascular disease (CVD) mortality risk. We conducted an individual-participant meta-analysis of nine cohort studies of men and women drawn from the British general population resulting in sample of 82 864 individuals. Body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) were measured directly. There were 6641 deaths (1998 CVD) during a mean of 8.1 years of follow-up. After adjustment, a one SD higher in WHR and WC was related to a higher risk of CVD mortality (hazard ratio [95% CI]): 1.15 (1.05-1.25) and 1.15 (1.04-1.27), respectively. The risk of CVD mortality also increased linearly across quintiles of both these abdominal obesity markers with a 66% increased risk in the highest quintile of WHR. In age- and sex-adjusted models only, BMI was related to CVD mortality but not in any other analyses. No major differences were revealed in the discrimination capabilities of models with BMI, WC or WHR for cardiovascular or total mortality outcomes. In conclusion, measures of abdominal adiposity, but not BMI, were related to an increased risk of CVD mortality. No difference was observed in discrimination capacities between adiposity markers.

Haemoglobin A1c, fasting glucose and future risk of elevated depressive symptoms over 2 years of follow-up in the English Longitudinal Study of Ageing

BACKGROUND

The cross-sectional association between impaired glucose/diabetes and depression is inconsistent. We examined the longitudinal associations between diabetes, indicators of glucose metabolism and depressive symptoms over 2 years of follow-up.

METHOD

Participants were 4338 men and women from the English Longitudinal Study of Ageing, a prospective study of community-dwelling older adults [aged 62.9 (s.d.=9.0) years, 45.2% men]. Depressive symptoms were assessed at baseline and after 2 years of follow-up using the eight-item Centre of Epidemiological Studies--Depression (CES-D) scale. Glycated haemoglobin (HbA1c) levels, fasting glucose and other biological and behavioural risk factors were also assessed at baseline.

RESULTS

Approximately 11.5% of the sample were categorized with elevated depressive symptoms at follow-up (a score ≥ 4 on the CES-D). There was an association between HbA1c and depressive symptoms at follow-up [per unit increase, odds ratio (OR) 1.17, 95% confidence interval (CI) 1.03-1.33] after adjustment for age and baseline CES-D. Cross-sectionally, the probability of depressive symptoms increased with increasing HbA1c levels until the value of 8.0% after which there was a plateau [p(curve)=0.03]. Compared with those with normal fasting glucose, participants with diabetes (confirmed through self-report or elevated fasting blood glucose) at baseline had an elevated risk of depressive symptoms at follow-up (OR 1.52, 95% CI 1.01-2.30) after adjusting for depressive symptoms at baseline, behavioural and sociodemographic variables, adiposity and inflammation.

CONCLUSIONS

These data suggest that poor glucose metabolism and diabetes are risk factors for future depression in older adults. There was no evidence of a U-shaped association.

Interventions for the prevention of overweight and obesity in preschool children: a systematic review of randomized controlled trials

The objective of this study was to analyse interventions for the prevention of overweight and obesity in children under 5 years of age. We carried out a systematic review focusing exclusively on randomized controlled trials (RCTs). Data sources include Medline, Cochrane Library, EMBASE, CINHAL, PsychInfo and Web of Science. Data were extracted from seventeen articles describing seven RCTs identified through electronic search, screening of references in systematic reviews, own files and contact with authors. RCTs were assessed with the Jadad scale. Four trials were carried out in preschool settings, one with an exclusive educational component, two with an exclusive physical activity component and one with both. Two trials were family-based, with education and counselling for parents and children. The remaining trial was carried out in maternity hospitals, with a training intervention on breastfeeding. None of the interventions had an effect in preventing overweight and obesity. The failure to show an effect may be due to the choice of outcomes, the quality of the RCTs, the suboptimal implementation of the interventions, the lack of focus on social and environmental determinants. More rigorous research is needed on interventions and on social and environmental factors that could impact on lifestyle.

Temporal trends in diabetes prevalence and key diabetes risk factors in Scotland, 2003-2008

AIMS

We assessed temporal trends in diabetes prevalence and key diabetes risk factors (obesity, physical activity, smoking) over 5 years in a nationally representative sample.

METHODS

Participants were drawn from the Scottish Health Surveys, which recruited two separate, nationally representative samples in 2003 (n = 7229, aged 50.5 ± 17.2 years) and 2008 (n = 6313, aged 51.8 ± 17.6 years). Prevalent diabetes was assessed from a self-reported physician's diagnosis, and high diabetes risk or undiagnosed cases were defined from HbA(1c) ≥ 6.0% (≥ 42 mmol/mol) to < 6.5% (< 47.5 mmol/mol) and ≥ 6.5% (≥ 47.5 mmol/mol), respectively.

RESULTS

Over 5 years there was an increased prevalence of diabetes (5.2 vs. 9.4% in 2003 and 2008, respectively) and in the prevalence of high diabetes risk (2.9 vs. 12.4%). These differences were accentuated in participants aged 65 years and above; for diabetes, there was a prevalence of 12 and 17.3% in 2003 and 2008, respectively, and, for high risk, the prevalence was 7.8 and 24.7%, respectively. There was also an increase in diabetes risk factors, including obesity and lack of physical activity, although these factors did not explain the diabetes trend.

CONCLUSIONS

These results suggest nearly a doubling in the prevalence of diabetes over 5 years in Scotland.

Lymphocyte cell counts in middle age are positively associated with subsequent all-cause and cardiovascular mortality

BACKGROUND

There is an association between higher white blood cell counts and all-cause and cardiovascular disease (CVD) mortality. However, little is known about the prognostic significance of circulating lymphocyte and lymphocyte subset numbers.

AIMS

The present study examined the association between T-, CD4-, CD8- and B-cell numbers, and the CD4:CD8 ratio, and all-cause and CVD mortality.

METHODS

Lymphocyte and lymphocyte subset numbers were measured by flow cytometry in a cohort of 4256 male middle-aged Vietnam-era US veterans. Mortality was tracked for 15 years and cause of death was determined from death certificates.

RESULTS

In fully adjusted survival analyses, high circulating T-cells numbers were associated with increased risk of both all-cause [hazard ratio (HR)=1.75, 95% confidence interval (CI) 1.15-2.66] and cardiovascular (HR=3.57, 95% CI 1.53-8.33) mortality. The former association appeared to reflect an effect for high CD8-cells numbers, the latter an effect for high CD4-cell numbers. For all-cause mortality, a high CD4:CD8 ratio was protective (HR=0.58, 95% CI 0.41-0.81). Cardiovascular mortality was also predicted by high B-cells numbers (HR=1.87, 95% CI 1.10-3.17).

CONCLUSION

Circulating lymphocyte and lymphocyte subset numbers may have substantial prognostic significance for both all-cause and CVD mortality.

Cortisol, dehydroepiandrosterone sulphate, their ratio and hypertension: evidence of associations in male veterans from the Vietnam Experience Study

Although clinical observations implicate cortisol in hypertension, the epidemiological evidence is less compelling. Little is known about the relationship between dehydroepiandrosterone sulphate (DHEAS) and hypertension, and nothing about the association with the cortisol:DHEAS ratio. The present analyses of data obtained from Vietnam-era US veterans examined the associations between cortisol, DHEAS, their ratio and hypertension. Participants were 4180 male veterans. From military files, telephone interviews and a medical examination, sociodemographic and health data were collected. At medical examination, a fasted morning blood sample was collected to assay serum cortisol and DHEAS, blood pressure measured and body mass index (BMI) determined. Hypertension was defined by having one of the following: a reported physician diagnosis, taking antihypertensive medication, an average systolic blood pressure ≥ 140 mm Hg and an average diastolic blood pressure ≥ 90 mm Hg. Cortisol and the cortisol:DHEAS ratio were positively associated with hypertension (P < 0.001), whereas DHEAS was negatively associated; the latter relationship was attenuated to non-significance (P = 0.06) in models that adjusted for age, sociodemographics, place of service, health behaviours and BMI. The present analyses provide confirmation of a positive association between cortisol and the cortisol:DHEAS ratio and population hypertension.

Oral disease and subsequent cardiovascular disease in people with type 2 diabetes: a prospective cohort study based on the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation (ADVANCE) trial

AIMS/HYPOTHESIS

While there are plausible biological mechanisms linking oral health with cardiovascular disease (CVD) and mortality rates, no study, to our knowledge, has examined this association in a representative population of people with type 2 diabetes.

METHODS

We used the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation (ADVANCE) study, a large, detailed, randomised controlled trial among a general population of individuals with type 2 diabetes. For the purposes of the present analyses, data from the trial are used within a prospective cohort study design. A total of 10,958 men and women, aged 55 to 88 years and with type 2 diabetes, participated in a baseline medical examination, during which they counted their number of natural teeth and reported the number of days that their gums had bled over the preceding year. Study members were followed up for mortality and morbidity over 5 years.

RESULTS

After controlling for a range of potential confounding factors, the group with no teeth had a markedly increased risk of death due to all causes (HR 1.48, 95% CI 1.24-1.78), CVD (1.35, 1.05-1.74) and non-CVD (1.64, 1.26-2.13), relative to the group with the most teeth (≥22 teeth). Frequency of bleeding gums was not associated with any of the outcomes of interest. There was no suggestion that treatment group or sex modified these relationships.

CONCLUSIONS/INTERPRETATION

In people with type 2 diabetes, oral disease, as indexed by fewer teeth, was related to an increased risk of death from all causes and of death due to CVD and non-CVD.

Early-life determinants of overweight and obesity: a review of systematic reviews

The aim of this paper was to review the evidence for early-life (from conception to 5 years of age) determinants of obesity. The design is review of published systematic reviews. Data sources included Medline, Embase, Web of Science, Cochrane Library, CINAHL, PsycINFO. Identification of 22 eligible reviews from a database of 12,021 independent publications. Quality of selected reviews assessed using the Assessment of Multiple Systematic Reviews score. Articles published after the reviews were used to confirm results. No review was classified as high quality, 11 as moderate and 11 as low. Factors associated with later overweight and obesity: maternal diabetes, maternal smoking, rapid infant growth, no or short breastfeeding, obesity in infancy, short sleep duration, <30 min of daily physical activity, consumption of sugar-sweetened beverages. Other factors were identified as potentially relevant, although the size of their effect is difficult to estimate. Maternal smoking, breastfeeding, infant size and growth, short sleep duration and television viewing are supported by better-quality reviews. It is difficult to establish a causal association between possible determinants and obesity, and the relative importance of each determinant. Future research should focus on early-life interventions to confirm the role of protective and risk factors and to tackle the high burden obesity represents for present and future generations.

Associations of diabetes mellitus with site-specific cancer mortality in the Asia-Pacific region

BACKGROUND

Owing to the increasing prevalence of obesity and diabetes in Asia, and the paucity of studies, we examined the influence of raised blood glucose and diabetes on cancer mortality risk.

MATERIALS AND METHODS

Thirty-six cohort Asian and Australasian studies provided 367, 361 participants (74% from Asia); 6% had diabetes at baseline. Associations between diabetes and site-specific cancer mortality were estimated using time-dependent Cox models, stratified by study and sex, and adjusted for age.

RESULTS

During a median follow-up of 4.0 years, there were 5992 deaths due to cancer (74% Asian; 41% female). Participants with diabetes had 23% greater risk of mortality from all-cause cancer compared with those without: hazard ratio (HR) 1.23 [95% confidence interval (CI) 1.12, 1.35]. Diabetes was associated with mortality due to cancer of the liver (HR 1.51; 95% CI 1.19, 1.91), pancreas (HR 1.78; 95% CI 1.20, 2.65), and, less strongly, colorectum (HR 1.32; 95% CI 0.98, 1.78). There was no evidence of sex- or region-specific differences in these associations. The population attributable fractions for cancer mortality due to diabetes were generally higher for Asia compared with non-Asian populations.

CONCLUSION

Diabetes is associated with increased mortality from selected cancers in Asian and non-Asian populations.

Obesity, overweight and liver disease in the Midspan prospective cohort studies

OBJECTIVES

To analyse the relationship between body mass index (BMI) and liver disease in men and women.

DESIGN

The Midspan prospective cohort studies.

PARTICIPANTS

The three studies were: Main study, screened in 1965-1968, workplaces across Scotland, the general population of the island of Tiree and mainland relatives; Collaborative study, conducted from 1970 to 1973, 27 workplaces in Glasgow, Clydebank and Grangemouth; Renfrew/Paisley general population study, screened in 1972-1976. After exclusions there were 16 522 men and 10 216 women, grouped by BMI into under/normal weight (< 25 kg m(-2)), overweight (25 to < 30 kg m(-2)) and obese (>or=30 kg m(-2)).

MEASUREMENTS

Relative rates (RRs) of liver disease mortality, subdivided into liver cancer and all other liver disease, by BMI category and per s.d. increase in BMI, followed-up to end 2007. RRs of liver disease from any diagnosis on the death certificate, hospital discharge records or cancer registrations (Collaborative and Renfrew/Paisley studies only 13 027 men and 9328 women). Analyses adjusted for age and study, then other confounders.

RESULTS

In total, 146 men (0.9%) and 61 women (0.6%) died of liver disease as main cause. There were strong associations of BMI with liver disease mortality in men (RR per s.d. increase in BMI=1.41 (95% confidence interval 1.21-1.65)). Obese men had more than three times the rate of liver disease mortality than under/normal weight men. Adjustment for other risk factors had very little effect. No substantial or robust associations were observed in women. In all, 325 men (2.5%) and 155 women (1.7%) had liver disease established from any source. Similar positive associations were observed for men, and there was evidence of a relationship in women.

CONCLUSIONS

BMI is related to liver disease, although not to liver disease mortality in women. The current rise in overweight and obesity may lead to a continuing epidemic of liver disease.

Intelligence in early adulthood and subsequent risk of unintentional injury over two decades: cohort study of 1 109 475 Swedish men

BACKGROUND

There is growing evidence of an inverse association between intelligence (IQ) and unintentional injuries.

METHODS

Analyses are based on a cohort of 1 109 475 Swedish men with IQ measured in early adulthood. Men were followed up for an average 24 years, and hospital admissions for unintentional injury were recorded.

RESULTS

198 133 (17.9%) men had at least one hospital admission for any unintentional injury during follow-up. The most common cause of unintentional injury was falling, followed by road accidents, poisoning, fire and drowning. In addition, 14 637 (1.3%) men had at least one admission for complications of medical care. After adjusting for confounding variables, lower IQ scores were associated with an elevated risk of any unintentional injury (HR (95% CI) per SD decrease in IQ: 1.15 (1.14 to 1.15)) and of cause-specific injuries other than drowning (poisoning (1.53 (1.49 to 1.57)), fire (1.36 (1.31 to 1.41)), road traffic accidents (1.25 (1.23 to 1.26)), medical complications (1.20 (1.18 to 1.22)) and falling (1.17 (1.16 to 1.18))). These gradients were stepwise across the full IQ range.

CONCLUSIONS

Low IQ scores in early adulthood were associated with a subsequently increased risk of unintentional injury. A greater understanding of mechanisms underlying these associations may provide opportunities and strategies for prevention.

Adult height and cancer mortality in Asia: the Asia Pacific Cohort Studies Collaboration

BACKGROUND

The observation that taller people experience an increased risk of selected cancers is largely restricted to Caucasian cohorts. These associations may plausibly differ in Asian populations. For the first time, we make direct comparison in the same analyses of the associations between height and a series of malignancies in Australasian (Caucasian) and Asian populations.

METHODS

Analyses were based on the Asia Pacific Cohort Studies Collaboration of 506 648 study participants (408 381 Asia, 98 267 Australasia) drawn from 38 population-based cohort studies. Cox proportional hazards regression was used to estimate the relationship between height and cancer rates.

RESULTS

A total of 3 272 600 person-years of follow-up gave rise to 7497 cancer deaths (4415 in Asia; 3082 in Australasia). After multiple adjustments and left censoring, taller individuals experienced increased rates of carcinoma of the intestine (men and women); all cancers, liver, lung, breast, 'other' malignancies (all women); and cancers of the prostate and bladder (men). No consistent regional (Asia versus Australasia) or sex differences were observed.

CONCLUSIONS

In the present study, taller men and women had an elevated risk of selected malignancies. These associations did not differ appreciably between Asian and Caucasian populations.