Body mass index and incident coronary heart disease in women: a population-based prospective study

Association between body shape index and coronary heart disease in individuals over 20 years old with obese

BACKGROUND

While body mass index (BMI) defines obesity as a well-established risk factor for cardiovascular disease, the paradoxical theory of BMI suggests that obesity may indeed have a favorable impact on the prognosis of cardiovascular disease. Therefore, this study aims to assess the correlation between body shape index (ABSI), which is a novel measure of obesity, and coronary heart disease (CHD) among obese individuals in the United States.

METHODS

The data from the National Health and Nutrition Examination Survey (NHANES) were evaluated by us for 5046 patients. We assessed the exposure variable ABSI, which includes waist circumference (WC), height, and BMI. The outcome variable was CHD.

RESULTS

The cross-sectional study included a total of 5046 obese adults aged over 20 years, with an average age (standard deviation: SD) of 49.86 (16.24) years and a male proportion of 44.57%.The odds ratio (OR) values for CHD in Model 1, Model 2, 3 were found to be 2.45 (95%CI: 2.12, 2.83), 1.53 (95%CI:1.30, 1.81) and 1.31 (95%CI:1.09, 1.56) per SD increase in ABSI, respectively. In the fully adjusted model, we designated participants in the T1 group as the reference group. Our findings indicate a significant increase in the prevalence of CHD (OR:1.82, 95%CI: 1.07-3.10) only within the T3 group. Although there is an increased prevalence of CHD (OR:1.32, 95%CI: 0.77-2.29) in the T2 group, no statistically significant difference was observed.

CONCLUSIONS

The increase in ABSI is strongly associated with the rise in CHD prevalence among obese individuals in the United States.

Exploratory Approach to Incorporating Carbon Footprint in Health Technology Assessment (HTA) Modelling: Cost-Effectiveness Analysis of Health Interventions in the United Kingdom

BACKGROUND

Health interventions contribute to the production of greenhouse gas emissions. Thus, reducing carbon footprint is essential in supporting the UK National Health Service (NHS) pathway to net zero. This study explores the approach in which carbon footprint can be included when applying Health Technology Assessment (HTA) modelling using obesity intervention in the United Kingdom (UK) as a case study.

METHODS

Using decision analytic modelling, we conducted an HTA incorporating the impacts of obesity-related treatment decisions on UK carbon emissions. A cohort Markov model was used to track the emissions of the UK population after receiving one of two obesity treatments: semaglutide and bariatric surgery.

RESULTS

This study introduced two new carbon measurement tools that may be useful for future policymaking, incremental carbon footprint effectiveness ratio (ICFER) and incremental carbon footprint cost ratio (ICFCR), which made it possible to assess the emission impacts of proposed health policies. Using the obesity intervention case study, we found that both treatments have an incremental cost-effectiveness ratio (ICER) of < £20,000 per quality-adjusted life-years (QALYs) gained. This is below the UK threshold, indicating that these are cost-effective treatments for obesity, but could increase the NHS carbon footprint. However, it could reduce the overall UK societal carbon footprint by reducing the number of people with obesity. The ICFCR shows a reduction of 1.13-4.51 kgCO2e (kilogram of carbon dioxide equivalent) for every pound spent on obesity treatment.

CONCLUSION

This study illustrates a case study for estimating the effect of health policies on carbon emissions and provides a quantitative measure for obesity-related treatment decisions.

Insulin resistance mediates obesity-related risk of cardiovascular disease: a prospective cohort study

BACKGROUND

The mechanisms linking obesity to cardiovascular disease (CVD) are still not clearly defined. Individuals who are overweight or obese often develop insulin resistance, mediation of the association between obesity and CVD through the insulin resistance seems plausible and has not been investigated. This study aimed to evaluate whether and to what extend the effect of general and central obesity on cardiovascular disease (CVD) is mediated by insulin resistance.

METHODS

A total of 94,136 participants without CVD at baseline were recruited from the Kailuan study. Insulin resistance was evaluated by the triglyceride-glucose (TyG) index, calculating as ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Mediation analysis using a new 2-stage regression method for survival data proposed by Valeri and VanderWeele was to explore the mediating effects of the TyG index on the association between obesity and CVD.

RESULTS

During a median follow-up of 13.01 years, we identified 7327 cases of CVD. Mediation analyses showed that 47.81% of the total association (hazard ratio [HR], 1.18; 95% confidence interval [CI], 1.12-1.24) between overweight and CVD was mediated through the TyG index (HR [indirect association], 1.07; 95% CI, 1.07-1.09), and the proportion mediated was 37.94% for general obesity. For central obesity, analysis by waist circumference, waist/hip, and waist/height categories yielded an attenuated proportion mediated of 32.01, 35.02, and 31.06% for obesity, taken normal weight as reference.

CONCLUSIONS

The association between obesity and CVD was mediated by TyG index, suggesting proper control of insulin resistance can be effective to reduce the effects of obesity on CVD.

Knowledge, Attitude, and Practice Toward Cardiovascular Diseases in the Lebanese Population

Background & Objective:

Cardiovascular diseases (CVD) are the leading cause of death globally. Assessing CVD knowledge, attitude, and practice (KAP) is necessary to spread awareness about CVD in Lebanon, their corresponding risk factors, and behaviors in which individuals can avoid or minimize the possibility of developing a CVD.

Subjects & Methods:

This was a case-control analytical study that targeted 921 CVD and non-CVD subjects. A questionnaire form was used to collect data related to patients’ demographics, socioeconomic status, habits, medical and family history, KAP towards CVD, and source of information. Data was analyzed using SPSS v.25.

Results:

Data from 921 participants were distributed over the CVD group (52.6% males aged 58.3 ± 13.7 years [n = 460]) and the non-CVD group (47.7% males aged 36.3 ± 15.4 years [n = 461]). CVD patients were significantly older than non-CVD subjects (p < 0.001). All three KAP scores of both groups were of poor to fair levels. Both CVD knowledge and attitude mean scores in CVD patients (26.6 ± 5.2 over 40 [66.50%] and 63.3 ± 10.2 over 85 [74.47%], respectively) were significantly higher than the ones of non-CVD subjects (23.5 ± 7.9 over 40 [58.75%] and 61.4 ± 12.4 over 85 [72.74%], respectively, p < 0.001). However, the CVD mean practice score was significantly lower in CVD patients (6.0 ± 1.7 over 9 [66.67%]) than the one of non-CVD subjects (6.3 ± 2.2 over 9 [70.00%] p < 0.001). Mostly, educational level (p < 0.001), governorate (p < 0.01), and smoking (p < 0.001) were predictors of KAP CVD in both groups.

Conclusion:

With an overall limited knowledge, attitude, and practice toward CVDs, the Lebanese population (with CVD or non-CVD) needs targeted national campaigns about CVD according to the identified predictors of CVD KAP to prevent and to alleviate the complications due to CVDs.

A prospective study of waist circumference trajectories and incident cardiovascular disease in China: the Kailuan Cohort Study

Background

Single measurements of waist circumference (WC) predict the incident cardiovascular disease (CVD); however, long-term patterns of WC and their association with the incidence of CVD are poorly characterized.

Objective

We aimed to identify WC trajectories and determine their association with incident CVD (stroke and myocardial infarction) and examine whether the association persisted among individuals without obesity.

Methods

We included 75,535 participants from a community-based cohort in China who were aged &gt;18 y and free of stroke, coronary artery disease, and cancer in 2010 (the baseline). WC and other covariates were repeatedly measured in 2006, 2008, and 2010. WC trajectories were identified by latent mixture modeling. A Cox proportional hazards model was used to examine the association between WC trajectories and incident CVD, after adjustment for age, sex, income, education, systolic blood pressure, lipid profiles, plasma concentrations of glucose, C-reactive protein, smoking, and alcohol drinking.

Results

We identified 4 WC trajectories based on 2006 WC measurement and change patterns during 2006–2010: low stable (n = 12,072; mean WC 74.1–75.1 cm), moderate stable (n = 41,750; mean WC 85.1–86.6 cm), moderate-high stable (n = 19,914; mean WC 95.6–97.2 cm), and high stable (n = 1,799; mean WC 106.3–110.9 cm). During 2010–2016, we documented 2819 incident CVD events. Compared with the low-stable group, groups with elevated WC trajectories had a higher risk of CVD events during 6 y of follow-up (2010–2016). Adjusted HRs (95% CIs) were 1.49 (1.21, 1.83) for the moderate stable group, 1.71(1.38, 2.12) for the moderate-high stable group, and 1.45 (1.06, 2.00) for the high stable group. After further adjusting for BMI or excluding obese participants, we observed similar results. The positive association between WC and incident CVD was higher in individuals who were aged &lt;60 y (P-interaction &lt; 0.0001).

Conclusions

WC trajectory patterns were associated with altered risk of CVD among Chinese adults, even among people without BMI-defined obesity. When stratifying by age, the association was observed to be higher in younger adults.

Becoming a parent: A systematic review and meta-analysis of changes in BMI, diet, and physical activity

Obesity prevalence rises fastest during young adulthood when weight, diet, and physical activity may be influenced by life events, including becoming a parent, but the impact is uncertain. We searched six electronic databases to July 2019 for longitudinal studies (both sexes) aged 15 to 35 years with a prospective pre-pregnancy/parenthood and post-delivery outcome. Of 11 studies (across 15 papers), six studies (women only) were eligible for meta-analysis of the difference in change in body mass index (BMI; kg/m2 ) between remaining without children and becoming a parent. Mean (±SD) BMI gain for non-mothers was 2.8 ± 1.3 kg/m2 (~7.5 kg for 164-cm woman) over 5.6 ± 3.1 years; 12.3% of baseline BMI (22.8 ± 2.5 kg/m2 ). Becoming a mother was associated with an additional BMI increase of 0.47 ± 0.26 kg/m2 (~1.3 kg), 4.3% of baseline BMI (22.8 ± 5.6 kg/m2 ); the one study including men reported no difference in change. Physical activity results were equivocal; 2/4 studies (women) and 2/2 (men) showed a greater decline in parents versus non-parents; diet (three studies) varied by dietary measure, mostly indicating no difference. Becoming a mother is associated with 17% greater absolute BMI gain than remaining childless. Motherhood BMI gain is additional to an alarming BMI increase among young women, highlighting the need for obesity prevention among all young women, including mothers.

Flawed methods and inappropriate conclusions for health policy on overweight and obesity: the Global BMI Mortality Collaboration meta-analysis

Guideline recommendations and health policy decisions rely on evidence from clinical and epidemiological studies. Adequate methodology and appropriate conclusions are essential to support healthcare and health policy decisions. An analysis of body mass index and mortality by the Global BMI Mortality Collaboration (GBMC) concluded that the association of excess body weight with higher mortality was similar worldwide and that overweight and obesity should be combated everywhere. To reach this conclusion, the GBMC used highly selected data, rather than a systematic approach. The GBMC initially chose individual participant data from 239 prospective studies with approximately 10.6 million participants. The GBMC then excluded over 60% of data and over 75% of fatal events by eliminating all cases with any reported disease at baseline or smoking history and all events within the first 5 years of follow-up. After applying these restrictions, the association of overweight with lower mortality was reversed and the association of obesity with higher mortality was increased. Given the major flaws in the selection process, in the adequacy of the data, in the data analysis, and in the interpretation, the GBMC conclusions should be viewed sceptically as a guide to action, either for clinical decisions or for public health in general. The flawed conclusion that overweight is uniformly associated with substantially increased risk of death and thus should be combated in any circumstances may lead not only to unjustified treatment efforts and potential harm in a wide range of clinical conditions but also to a tremendous waste of resources.

An update on physical health and economic consequences of overweight and obesity

Overweight and obesity (OW and OB) have been on the increase globally and posed health risks to the world's population of all ages, including pre-born babies, children, adolescents, adults and elderly people, via their comorbid conditions. Excellent examples of comorbidities associated with obesity include cancer, cardiovascular diseases (CVD) and type 2 diabetes mellitus (T2DM). In this article, we aimed to review and update scientific evidence regarding the relationships between obesity and its common physical health consequences, including CVD, T2DM, hypertension, ischemic stroke, cancer, dyslipidemia and reproductive disorders. In addition, the economic burden of OW and OB will be discussed. Abundant evidence is found to support the associations between obesity and other diseases. In general, the odd ratios, risk ratios or hazard ratios are often higher in OW and OB people than in the normal-weight ones. However, the molecular mechanism of how OW and OB induce the development of other diseases has not been fully understood. Figures also showed that obesity and its-related disorders exert enormous pressure on the economy which is projected to increase. This review highlights the fact that obesity can lead to numerous lethal health problems; therefore, it requires a lot of economic resources to fight against this epidemic.

Body-mass index, blood pressure, and cause-specific mortality in India: a prospective cohort study of 500 810 adults

BACKGROUND

The association between cause-specific mortality and body-mass index (BMI) has been studied mainly in high-income countries. We investigated the relations between BMI, systolic blood pressure, and mortality in India.

METHODS

Men and women aged 35 years or older were recruited into a prospective study from the general population in Chennai, India between Jan 1, 1998, and Dec 31, 2001. Participants were interviewed (data collected included age, sex, education, socioeconomic status, medical history, tobacco smoking, and alcohol intake) and measured (height, weight, and blood pressure). Deaths were identified by linkage to Chennai city mortality records and through active surveillance by household visits from trained graduate non-medical fieldworkers. After the baseline survey, households were visited once in 2002-05, then biennially until 2015. During these repeat visits, structured narratives of any deaths that took place before March 31, 2015, were recorded for physician coding. During 2013-14, a random sample of participants was also resurveyed as per baseline to assess long-term variability in systolic blood pressure and BMI. Cox regression (standardised for tobacco, alcohol, and social factors) was used to relate mortality rate ratios (RRs) at ages 35-69 years to systolic blood pressure, BMI, or BMI adjusted for usual systolic blood pressure.

FINDINGS

500 810 participants were recruited. After exclusion of those with chronic disease or incomplete data, 414 746 participants aged 35-69 years (mean 46 [SD 9]; 45% women) remained. At recruitment, mean systolic blood pressure was 127 mm Hg (SD 15), and mean BMI was 23·2 kg/m2 (SD 3·8). Correlations of resurvey and baseline measurements were 0·50 for systolic blood pressure and 0·88 for BMI. Low BMI was strongly associated with poverty, tobacco, and alcohol. Of the 29 519 deaths at ages 35-69 years, the cause was vascular for 14 935 deaths (12 504 cardiac, 1881 stroke, and 550 other). Vascular mortality was strongly associated with systolic blood pressure: RRs per 20 mm Hg increase in usual systolic blood pressure were 2·45 (95% CI 2·16-2·78) for stroke mortality, 1·74 (1·64-1·84) for cardiac mortality, and 1·84 (1·75-1·94) for all vascular mortality. Although BMI strongly affected systolic blood pressure (an increase of about 1 mm Hg per kg/m2) and diabetes prevalence, BMI was little related to cardiac or stroke mortality, with only small excesses even for grade 1 obesity (ie, BMIs of 30·0-35·0 kg/m2). After additional adjustment for usual systolic blood pressure, BMI was inversely related to cardiac and stroke mortality throughout the range 15·0-30·0 kg/m2: when underweight participants (ie, BMI 15·0-18·5 kg/m2) were compared with overweight participants (ie, BMI 25·0-30·0 kg/m2), the blood-pressure-adjusted RR was 1·28 (95% CI 1·20-1·38) for cardiac mortality and 1·46 (1·22-1·73) for stroke mortality.

INTERPRETATION

In this South Asian population, BMI was little associated with vascular mortality, even though increased BMI is associated with increased systolic blood pressure, which in turn is associated with increased vascular mortality. Hence, some close correlates of below-average BMI must have important adverse effects, which could be of relevance in all populations.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK.

The Science of Obesity Management: An Endocrine Society Scientific Statement

The prevalence of obesity, measured by body mass index, has risen to unacceptable levels in both men and women in the United States and worldwide with resultant hazardous health implications. Genetic, environmental, and behavioral factors influence the development of obesity, and both the general public and health professionals stigmatize those who suffer from the disease. Obesity is associated with and contributes to a shortened life span, type 2 diabetes mellitus, cardiovascular disease, some cancers, kidney disease, obstructive sleep apnea, gout, osteoarthritis, and hepatobiliary disease, among others. Weight loss reduces all of these diseases in a dose-related manner-the more weight lost, the better the outcome. The phenotype of "medically healthy obesity" appears to be a transient state that progresses over time to an unhealthy phenotype, especially in children and adolescents. Weight loss is best achieved by reducing energy intake and increasing energy expenditure. Programs that are effective for weight loss include peer-reviewed and approved lifestyle modification programs, diets, commercial weight-loss programs, exercise programs, medications, and surgery. Over-the-counter herbal preparations that some patients use to treat obesity have limited, if any, data documenting their efficacy or safety, and there are few regulatory requirements. Weight regain is expected in all patients, especially when treatment is discontinued. When making treatment decisions, clinicians should consider body fat distribution and individual health risks in addition to body mass index.

Health and economic benefits of reducing sugar intake in the USA, including effects via non-alcoholic fatty liver disease: a microsimulation model

OBJECTIVES

Excessive consumption of added sugars in the human diet has been associated with obesity, type 2 diabetes (T2D), coronary heart disease (CHD) and other elements of the metabolic syndrome. Recent studies have shown that non-alcoholic fatty liver disease (NAFLD) is a critical pathway to metabolic syndrome. This model assesses the health and economic benefits of interventions aimed at reducing intake of added sugars.

METHODS

Using data from US National Health Surveys and current literature, we simulated an open cohort, for the period 2015-2035. We constructed a microsimulation model with Markov chains for NAFLD (including steatosis, non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma (HCC)), body mass index, T2D and CHD. We assessed reductions in population disease prevalence, disease-attributable disability-adjusted life years (DALYs) and costs, with interventions that reduce added sugars consumption by either 20% or 50%.

FINDINGS

The model estimated that a 20% reduction in added sugars intake will reduce prevalence of hepatic steatosis, NASH, cirrhosis, HCC, obesity, T2D and CHD. Incidence of T2D and CHD would be expected to decrease by 19.9 (95% CI 12.8 to 27.0) and 9.4 (95% CI 3.1 to 15.8) cases per 100 000 people after 20 years, respectively. A 20% reduction in consumption is also projected to annually avert 0.767 million (M) DALYs (95% CI 0.757M to 0.777M) and a total of US$10.3 billion (B) (95% CI 10.2B to 10.4B) in discounted direct medical costs by 2035. These effects increased proportionally when added sugars intake were reduced by 50%.

CONCLUSIONS

The decrease in incidence and prevalence of disease is similar to results in other models, but averted costs and DALYs were higher, mainly due to inclusion of NAFLD and CHD. The model suggests that efforts to reduce consumption of added sugars may result in significant public health and economic benefits.

The role of health-related behavioural factors in accounting for inequalities in coronary heart disease risk by education and area deprivation: prospective study of 1.2 million UK women

BACKGROUND

Some recent research has suggested that health-related behaviours, such as smoking, might explain much of the socio-economic inequalities in coronary heart disease (CHD) risk. In a large prospective study of UK women, we investigated the associations between education and area deprivation and CHD risk and assessed the contributions of smoking, alcohol consumption, physical activity and body mass index (BMI) to these inequalities.

METHODS

After excluding women with heart disease, stroke or cancer at recruitment, 1,202,983 women aged 56 years (SD 5 years) on average, were followed for first coronary event (hospital admission or death) and for CHD mortality. Relative risks of CHD were estimated by Cox regression, and the extent to which any association could be accounted for by smoking, alcohol, physical inactivity, and BMI was assessed by calculating the percentage reduction in the relevant likelihood-ratio (LR) statistic after adjustment for these factors, separately and together.

RESULTS

A total of 71,897 women had a first CHD event (hospital admission or death) and 6032 died from CHD during 12 years follow-up. In analyses adjusted by age, birth cohort and region of residence only, lower levels of education and greater deprivation were associated with higher risks of CHD (P heterogeneity < 0.0001 for each); associations for education were found within every level of deprivation and for deprivation were found within every level of education. Smoking, alcohol consumption, physical inactivity and BMI accounted for most of the associations (adjustment for all four factors together reduced the LR statistics for education and for deprivation by 76 % and 71 %, respectively, for first CHD event; and by 87 % and 79 %, respectively, for CHD mortality). Of these four factors, adjustment for smoking resulted in the largest reduction in the LR statistic. Given the large reduction in the predictive values of education and deprivation after adjustment for only four health-related behavioural factors recorded just at recruitment, residual confounding might plausibly account for the remaining associations.

CONCLUSIONS

Most of the association between CHD risk and education and area deprivation in UK women is accounted for by health-related behaviours, particularly by smoking and to a lesser extent by alcohol consumption, physical inactivity and BMI.

Statin adherence and risk of acute cardiovascular events among women: a cohort study accounting for time-dependent confounding affected by previous adherence

OBJECTIVES

Previous studies on the effect of statin adherence on cardiovascular events in the primary prevention of cardiovascular disease have adjusted for time-dependent confounding, but potentially introduced bias into their estimates as adherence and confounders were measured simultaneously. We aimed to evaluate the effect when accounting for time-dependent confounding affected by previous adherence as well as time sequence between factors.

DESIGN

Retrospective cohort study.

SETTING

Finnish healthcare registers.

PARTICIPANTS

Women aged 45-64 years initiating statin use for primary prevention of cardiovascular disease in 2001-2004 (n=42 807).

OUTCOMES

Acute cardiovascular event defined as a composite of acute coronary syndrome and acute ischaemic stroke was our primary outcome. Low-energy fractures were used as a negative control outcome to evaluate the healthy-adherer effect.

RESULTS

During the 3-year follow-up, 474 women experienced the primary outcome event and 557 suffered a low-energy fracture. The causal HR estimated with marginal structural model for acute cardiovascular events for all the women who remained adherent (proportion of days covered ≥80%) to statin therapy during the previous adherence assessment year was 0.78 (95% CI: 0.65 to 0.94) when compared with everybody remaining non-adherent (proportion of days covered <80%). The result was robust against alternative model specifications. Statin adherers had a potentially reduced risk of experiencing low-energy fractures compared with non-adherers (HR 0.90, 95% CI 0.76 to 1.07).

CONCLUSIONS

Our study, which took into account the time dependence of adherence and confounders, as well as temporal order between these factors, is support for the concept that adherence to statins in women in primary prevention decreases the risk of acute cardiovascular events by about one-fifth in comparison to non-adherence. However, part of the observed effect of statin adherence on acute cardiovascular events may be due to the healthy-adherer effect.

Obesity or obesities? Controversies on the association between body mass index and premature mortality

Obesity is still defined on the basis of body mass index (BMI) and BMI in itself is generally accepted as a strong predictor of overall early mortality. However, an inverse association between BMI and mortality has been reported in patients with many disease states and in several clinical settings: hemodialysis, cardiovascular diseases, hypertension, stroke, diabetes, chronic obstructive pulmonary disease, surgery, etc. This unexpected phenomenon is usually called obesity-survival paradox (OP). The contiguous concepts of metabolically healthy obesity (MHO, a phenotype having BMI ≥ 30 but not having any metabolic syndrome component and having a homeostasis model assessment of insulin resistance, HOMA, <2.5) and metabolically obese normal weight (MONW, normal-weight individuals displaying obesity-related phenotypic characteristics) have received a great deal of attention in recent years. The interactions that link MHO, MONW and OP with body composition, fat distribution, aging and cardiorespiratory fitness are other crucial areas of research. The article is an introductory narrative overview of the origin and current use of the concepts of MHO, MONW and OP. These phenomena are very controversial and appear as a consequence of the frail current diagnostic definition of obesity based only on BMI. A new commonly established characterization and classification of obesities based on a number of variables is needed urgently.

Adiposity throughout adulthood and risk of sudden cardiac death in women

BACKGROUND

Sudden cardiac death (SCD) is often the first manifestation of coronary heart disease (CHD) among women. Data regarding BMI and risk of SCD are limited and conflicting.

OBJECTIVES

We examined the association of BMI repeatedly measured over 32 years and BMI during early and mid-adulthood with risk of SCD in the Nurses' Health Study.

METHODS

We prospectively followed 72,484 women free of chronic disease from 1980-2012. We ascertained adult height, current weight, and weight at age 18 at baseline and updated weight biennially. The primary endpoint was SCD (n=445).

RESULTS

When updated biennially, higher BMI was associated with greater SCD risk after adjusting for confounders (p, linear trend: <0.001). Compared to a BMI of 21.0-22.9, the multivariate RR (95%CI) of SCD was 1.46 (1.05, 2.04) for BMI 25.0-29.9, 1.46 (1.00, 2.13) for BMI 30.0-34.9 and 2.18 (1.44, 3.28) for BMI ≥35.0. Among women with a BMI ≥35.0, SCD remained elevated even after adjustment for interim development of CHD and other mediators (RR: 1.72; 95%CI: 1.13, 2.60). In contrast, the association between BMI and fatal CHD risk was completely attenuated after adjustment for mediators. The magnitude of the association between BMI and SCD was greater when BMI was assessed at baseline or at age 18, at which time SCD risk remained significantly elevated at BMI≥30 after adjustment for mediators.

CONCLUSIONS

Higher BMI was associated with greater risk of SCD, particularly when assessed earlier in adulthood. Strategies to maintain a healthy weight throughout adulthood may minimize SCD incidence.

The clinical profile of women with stable ischaemic heart disease in Spain. More effort is needed in secondary prevention. SIRENA study

OBJECTIVES

Cardiovascular diseases are the leading cause of death for women, especially ischaemic heart disease, which is still considered a man's disease. In Spain, there are various registries on ischaemic heart disease, although none are exclusively for women. The objectives of the SIRENA study were to describe the clinical profile of women with ischaemic heart disease treated in cardiology consultations, to estimate its prevalence of cardiovascular risk factors and understand its clinical management.

PATIENTS AND METHODS

A multicentre observational study was conducted with a sample of 631 women with stable ischaemic heart disease, consecutively included during cardiology consultations. Forty-one researchers from all over Spain participated in the study.

RESULTS

The mean age was 68.5 years. The clinical presentation was in the form of acute coronary syndrome in up to 67.2% of the patients. The prevalence of cardiovascular risk factors was high (77.7% of the patients had hypertension, 40.7% had diabetes and 68% had dyslipidaemia), with 30.7% having uncontrolled hypertension, 78.4% having LDL-cholesterol levels higher than 70mg/dL and 49.2% having HbA1c levels greater than 7%. The considerable majority of the patients underwent optimal medical treatment with antiplatelet agents, beta-blockers, renin-angiotensin-aldosterone system blockers and hypolipidaemic agents. Coronary angiography was performed for 88.3% of the patients, and 63.4% underwent percutaneous coronary intervention.

CONCLUSIONS

Women with stable ischaemic heart disease in Spain initially present some form of acute coronary syndrome and a high prevalence of inadequately controlled cardiovascular risk factors, despite undergoing optimal medical therapy. A high percentage of these women undergo coronary revascularisation. Increased efforts are required for secondary prevention in women with stable ischaemic heart disease.

Differential associations of job control components with both waist circumference and body mass index

INTRODUCTION

The Job Demand-Control-Support (JDCS) model is commonly used to investigate associations between psychosocial work factors and employee health, yet research considering obesity using the JDCS model remains inconclusive.

OBJECTIVE

This study investigates which parts of the JDCS model are associated with measures of obesity and provides a comparison between waist circumference (higher values imply central obesity) and body mass index (BMI, higher values imply overall obesity).

METHODS

Contrary to common practice, in this study the JDCS components are not reduced into composite or global scores. In light of emerging evidence that the two components of job control (skill discretion and decision authority) could have differential associations with related health outcomes, components of the JDCS model were analysed at the subscale level. A cross-sectional design with a South Australian cohort (N = 450) combined computer-assisted telephone interview data and clinic-measured height, weight and waist circumference.

RESULTS

After controlling for sex, age, household income, work hours and job nature (blue vs. white-collar), the two components of job control were the only parts of the JDCS model to hold significant associations with measures of obesity. Notably, the associations between skill discretion and waist circumference (b = -.502, p = .001), and skill discretion and BMI (b = -.163, p = .005) were negative. Conversely, the association between decision authority and waist circumference (b = .282, p = .022) was positive.

CONCLUSION

These findings are significant since skill discretion and decision authority are typically combined into a composite measure of job control or decision latitude. Our findings suggest skill discretion and decision authority should be treated separately since combining these theoretically distinct components may conceal their differential associations with measures of obesity, masking their individual importance. Psychosocial work factors displayed stronger associations and explained greater variance in waist circumference compared with BMI, and possible reasons for this are discussed.

Age at menarche and risks of coronary heart and other vascular diseases in a large UK cohort

BACKGROUND

Early menarche has been associated with increased risk of coronary heart disease (CHD), but most studies were relatively small and could not assess risk across a wide range of menarcheal ages; few have examined associations with other vascular diseases. We examined CHD, cerebrovascular disease, and hypertensive disease risks by age at menarche in a large prospective study of UK women.

METHODS AND RESULTS

In 1.2 million women (mean±SD age, 56±5 years) without previous heart disease, stroke, or cancer, menarcheal age was reported to be 13 years by 25%, ≤10 years by 4%, and ≥17 years by 1%. After 11.6 years of follow-up, 73 378 women had first hospitalization for or death from CHD, 25 426 from cerebrovascular disease, and 249 426 from hypertensive disease. Using Cox regression, we calculated relative risks for each vascular outcome by single year of menarcheal age. The relationship was U-shaped for CHD. Compared with women with menarche at 13 years, the adjusted relative risk for CHD for menarche at ≤10 years of age was 1.27 (95% confidence interval, 1.22-1.31; P<0.0001) and for menarche at ≥17 years of age was 1.23 (95% confidence interval, 1.16-1.30; P<0.0001). U-shaped relationships were also seen for cerebrovascular and hypertensive disease, although the magnitudes of these risks for early and late menarche were smaller than those for CHD.

CONCLUSIONS

In this cohort, the relation of age at menarche to vascular disease risk was U shaped, with both early and late menarche being associated with increased risk. Associations were weaker for cerebrovascular and hypertensive disease than for CHD.

Long term risk factors for coronary heart disease and stroke: influence of duration of follow-up over four decades of mortality surveillance

AIM

While cohort studies have revealed a range of risk factors for coronary heart disease and stroke, the extent to which the strength of these associations varies according to duration of follow-up in studies with extended disease surveillance is unclear. This was the aim of the present study.

METHODS AND RESULTS

Initiated in 1967/70, the original Whitehall study is an on-going cohort study of 15,402 male UK government workers free of coronary heart disease when they took part in a baseline medical examination during which a range of standard risk factors was measured. In analyses in which we stratified by duration of follow-up, there was evidence of time-dependency for most risk factor-disease relationships. Thus, the associations of systolic and diastolic blood pressure, total cholesterol and cigarette smoking with coronary heart disease and stroke diminished in strength with increasing duration of follow-up, whereas the magnitude of the body mass index-coronary heart disease relation was unchanged. For example, the age-adjusted hazard ratios (95% confidence interval) for cigarette smoking (versus never smoked) in relation to coronary heart disease were: 2.49 (1.80, 3.44), 1.65 (1.34, 2.03), 1.36 (1.15, 1.61) and 1.32 (1.10, 1.58) for follow-up periods 0-10, 10-20, 20-30 and 30+ years, respectively.

CONCLUSION

Despite a general diminution in the strength of effect over time, even in the fourth decade of follow-up, classic risk factors retained some predictive capacity for coronary heart disease and, to a lesser degree, stroke.

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.

Joint effects of serum ferritin and body mass index on the risk of coronary artery disease: a case-control study

OBJECTIVES

Serum ferritin and body mass index (BMI) have been reportedly associated with coronary artery disease (CAD) risk. The aim of the present study was to explore the interaction between serum ferritin and BMI on CAD risk.

DESIGN

Hospital-based case-control study.

SETTING

Patients with CAD and the controls were recruited from Qilu Hospital, Shandong University.

PARTICIPANTS

258 CAD cases and 282 healthy controls.

METHODS

Multiplicative interaction was assessed through a cross-product interaction term in a multivariate logistic regression model. The effect of serum ferritin and BMI were evaluated per 50 µg/L and per 2 kg/m(2), respectively. The presence of additive interaction between serum ferritin and BMI was evaluated by calculation of the relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S).

RESULTS

The ORs and 95% CI of the serum ferritin-BMI product term on a multiplicative scale in the univariate and multivariate models were 0.943 (0.904 to 0.984) and 1.004 (0.951 to 1.059), respectively. There was also evidence for interaction on an additive scale; the RERI (95% CI), AP (95% CI) and S (95% CI) in the univariate model were 0.314 (0.026 to 1.506), 0.107 (0.017 to 0.241) and 1.194 (1.053 to 1.406), respectively. After adjusting for the potential confounders, the estimates and 95% CIs for the aforementioned three measures were 0.004 (-0.016 to 0.311), 0.004 (-0.016 to 0.191) and 1.039 (0.774 to 1.285), respectively.

CONCLUSIONS

Serum ferritin and BMI had an additive interaction on the risk of CAD in Chinese population. Further investigations with big sample size are necessary for confirming this additive interaction.

Body mass index and incident hospitalisation for cardiovascular disease in 158 546 participants from the 45 and Up Study

Objective:

To investigate the relationship between fine gradations in body mass index (BMI) and risk of hospitalisation for different types of cardiovascular disease (CVD).

Design, Subjects and Methods:

The 45 and Up Study is a large-scale Australian cohort study initiated in 2006. Self-reported data from 158 546 individuals with no history of CVD were linked prospectively to hospitalisation and mortality data. Hazard ratios (HRs) of incident hospitalisation for specific CVD diagnoses in relation to baseline BMI categories were estimated using Cox regression, adjusting for age, sex, region of residence, income, education, smoking, alcohol intake and health insurance status.

Results:

There were 9594 incident CVD admissions over 583 100 person-years among people with BMI⩾20 kg m⁻², including 3096 for ischaemic heart disease (IHD), 1373 for stroke, 411 for peripheral vascular disease (PVD) and 320 for heart failure. The adjusted HR of hospitalisation for all CVD diagnoses combined increased significantly with increasing BMI (P(trend) <0.0001)). The HR of IHD hospitalisation increased by 23% (95% confidence interval (95% CI): 18–27%) per 5 kg m⁻² increase in BMI (compared to BMI 20.0–22.49 kg m⁻², HR (95% CI) for BMI categories were: 22.5–24.99=1.25 (1.08–1.44); 25–27.49=1.43 (1.24–1.65); 27.5–29.99=1.64 (1.42–1.90); 30–32.49=1.63 (1.39–1.91) and 32.5–50=2.10 (1.79–2.45)). The risk of hospitalisation for heart failure showed a significant, but nonlinear, increase with increasing BMI. No significant increase was seen with above-normal BMI for stroke or PVD. For other specific classifications of CVD, HRs of hospitalisation increased significantly with increasing BMI for: hypertension; angina; acute myocardial infarction; chronic IHD; pulmonary embolism; non-rheumatic aortic valve disorders; atrioventricular and left bundle-branch block; atrial fibrillation and flutter; aortic aneurysm; and phlebitis and thrombophlebitis.

Conclusion:

The risk of hospitalisation for a wide range of CVD subtypes increases with relatively fine increments in BMI. Obesity prevention strategies are likely to benefit from focusing on bringing down the mean BMI at the population level, in addition to targeting those with a high BMI.