Body composition and risk factors for cardiovascular disease in global multi-ethnic populations.

BACKGROUND: No large-scale studies have compared associations between body composition and cardiovascular risk factors across multi-ethnic populations. METHODS: Population-based surveys included 30,721 Malay, 10,865 Indian and 25,296 Chinese adults from The Malaysian Cohort, and 413,737 White adults from UK Biobank. Sex-specific linear regression models estimated associations of anthropometry and body composition (body mass index [BMI], waist circumference [WC], fat mass, appendicular lean mass) with systolic blood pressure (SBP), low-density lipoprotein cholesterol (LDL-C), triglycerides and HbA1c. RESULTS: Compared to Malay and Indian participants, Chinese adults had lower BMI and fat mass while White participants were taller with more appendicular lean mass. For BMI and fat mass, positive associations with SBP and HbA1c were strongest among the Chinese and Malay and weaker in White participants. Associations with triglycerides were considerably weaker in those of Indian ethnicity (eg 0.09 [0.02] mmol/L per 5 kg/m2 BMI in men, vs 0.38 [0.02] in Chinese). For appendicular lean mass, there were weak associations among men; but stronger positive associations with SBP, triglycerides, and HbA1c, and inverse associations with LDL-C, among Malay and Indian women. Associations between WC and risk factors were generally strongest in Chinese and weakest in Indian ethnicities, although this pattern was reversed for HbA1c. CONCLUSION: There were distinct patterns of adiposity and body composition and cardiovascular risk factors across ethnic groups. We need to better understand the mechanisms relating body composition with cardiovascular risk to attenuate the increasing global burden of obesity-related disease.

Development and Internal Validation of a Risk Score to Detect Asymptomatic Carotid Stenosis.

OBJECTIVE: Asymptomatic carotid stenosis (ACS) is associated with an increased risk of ischaemic stroke and myocardial infarction. Risk scores have been developed to detect individuals at high risk of ACS, thereby enabling targeted screening, but previous external validation showed scope for refinement of prediction by adding additional predictors. The aim of this study was to develop a novel risk score in a large contemporary screened population. METHODS: A prediction model was developed for moderate (≥50%) and severe (≥70%) ACS using data from 596 469 individuals who attended screening clinics. Variables that predicted the presence of ≥50% and ≥70% ACS independently were determined using multivariable logistic regression. Internal validation was performed using bootstrapping techniques. Discrimination was assessed using area under the receiver operating characteristic curves (AUROCs) and agreement between predicted and observed cases using calibration plots. RESULTS: Predictors of ≥50% and ≥70% ACS were age, sex, current smoking, diabetes mellitus, prior stroke/transient ischaemic attack, coronary artery disease, peripheral arterial disease, blood pressure, and blood lipids. Models discriminated between participants with and without ACS reliably, with an AUROC of 0.78 (95% confidence interval [CI] 0.77-0.78) for ≥ 50% ACS and 0.82 (95% CI 0.81-0.82) for ≥ 70% ACS. The number needed to screen in the highest decile of predicted risk to detect one case with ≥50% ACS was 13 and that of ≥70% ACS was 58. Targeted screening of the highest decile identified 41% of cases with ≥50% ACS and 51% with ≥70% ACS. CONCLUSION: The novel risk model predicted the prevalence of ACS reliably and performed better than previous models. Targeted screening among the highest decile of predicted risk identified around 40% of all cases with ≥50% ACS. Initiation or intensification of cardiovascular risk management in detected cases might help to reduce both carotid related ischaemic strokes and myocardial infarctions.

Body-mass index, blood pressure, diabetes and cardiovascular mortality in Cuba: prospective study of 146,556 participants.

BACKGROUND: Cardiovascular disease accounts for about one-third of all premature deaths (ie, age < 70) in Cuba. Yet, the relevance of major risk factors, including systolic blood pressure (SBP), diabetes, and body-mass index (BMI), to cardiovascular mortality in this population remains unclear. METHODS: In 1996-2002, 146,556 adults were recruited from the general population in five areas of Cuba. Participants were interviewed, measured (height, weight and blood pressure) and followed up by electronic linkage to national death registries until Jan 1, 2017; in 2006-08, 24,345 participants were resurveyed. After excluding all with missing data, cardiovascular disease at recruitment, and those who died in the first 5 years, Cox regression (adjusted for age, sex, education, smoking, alcohol and, where appropriate, BMI) was used to relate cardiovascular mortality rate ratios (RRs) at ages 35-79 years to SBP, diabetes and BMI; RR were corrected for regression dilution to give associations with long-term average (ie, 'usual') levels of SBP and BMI. RESULTS: After exclusions, there were 125,939 participants (mean age 53 [SD12]; 55% women). Mean SBP was 124 mmHg (SD15), 5% had diabetes, and mean BMI was 24.2 kg/m2 (SD3.6); mean SBP and diabetes prevalence at recruitment were both strongly related to BMI. During follow-up, there were 4112 cardiovascular deaths (2032 ischaemic heart disease, 832 stroke, and 1248 other). Cardiovascular mortality was positively associated with SBP (>=120 mmHg), diabetes, and BMI (>=22.5 kg/m2): 20 mmHg higher usual SBP about doubled cardiovascular mortality (RR 2.02, 95%CI 1.88-2.18]), as did diabetes (2.15, 1.95-2.37), and 10 kg/m2 higher usual BMI (1.92, 1.64-2.25). RR were similar in men and in women. The association with BMI and cardiovascular mortality was almost completely attenuated following adjustment for the mediating effect of SBP. Elevated SBP (>=120 mmHg), diabetes and raised BMI (>=22.5 kg/m2) accounted for 27%, 14%, and 16% of cardiovascular deaths, respectively. CONCLUSIONS: This large prospective study provides direct evidence for the effects of these major risk factors on cardiovascular mortality in Cuba. Despite comparatively low levels of these risk factors by international standards, the strength of their association with cardiovascular death means they nevertheless exert a substantial impact on premature mortality in Cuba.

Fresh Fruit Consumption and Major Cardiovascular Disease in China.

BACKGROUND: In Western populations, a higher level of fruit consumption has been associated with a lower risk of cardiovascular disease, but little is known about such associations in China, where the consumption level is low and rates of stroke are high. METHODS: Between 2004 and 2008, we recruited 512,891 adults, 30 to 79 years of age, from 10 diverse localities in China. During 3.2 million person-years of follow-up, 5173 deaths from cardiovascular disease, 2551 incident major coronary events (fatal or nonfatal), 14,579 ischemic strokes, and 3523 intracerebral hemorrhages were recorded among the 451,665 participants who did not have a history of cardiovascular disease or antihypertensive treatments at baseline. Cox regression yielded adjusted hazard ratios relating fresh fruit consumption to disease rates. RESULTS: Overall, 18.0% of participants reported consuming fresh fruit daily. As compared with participants who never or rarely consumed fresh fruit (the "nonconsumption" category), those who ate fresh fruit daily had lower systolic blood pressure (by 4.0 mm Hg) and blood glucose levels (by 0.5 mmol per liter [9.0 mg per deciliter]) (P<0.001 for trend for both comparisons). The adjusted hazard ratios for daily consumption versus nonconsumption were 0.60 (95% confidence interval [CI], 0.54 to 0.67) for cardiovascular death, and 0.66 (95% CI, 0.58 to 0.75), 0.75 (95% CI, 0.72 to 0.79), and 0.64 (95% CI, 0.56 to 0.74), respectively, for incident major coronary events, ischemic stroke, and hemorrhagic stroke. There was a strong log-linear dose-response relationship between the incidence of each outcome and the amount of fresh fruit consumed. These associations were similar across the 10 study regions and in subgroups of participants defined by baseline characteristics. CONCLUSIONS: Among Chinese adults, a higher level of fruit consumption was associated with lower blood pressure and blood glucose levels and, largely independent of these and other dietary and nondietary factors, with significantly lower risks of major cardiovascular diseases. (Funded by the Wellcome Trust and others.).

Age at Menarche and Incidence of Diabetes: A Prospective Study of 300,000 Women in China.

Previous studies of predominantly Western populations have reported inconsistent associations between age at menarche and risk of diabetes. We examined this relationship among Chinese women, who generally experience menarche at a later age than Western women. In 2004-2008, China Kadoorie Biobank recruited 302,632 women aged 30-79 years from 10 areas across China, and recorded 5,391 incident cases of diabetes during 7 years of follow-up among 270,345 women without baseline diabetes, cardiovascular disease or cancer. Cox regression models yielded adjusted hazard ratios for incident diabetes associated with age at menarche. Overall, the mean age at menarche was 15.4 years, and decreased across successive generations. Age at menarche was linearly and inversely associated with incident diabetes, with adjusted hazard ratio of 0.96 (95% confidence interval (CI): 0.94, 0.97) per year delay. Hazard ratios were greater in younger generations (for women born in the 1960s-1970s, hazard ratio (HR) = 0.93, 95% CI: 0.90, 0.97; for women born in the 1950s, HR = 0.95, 95% CI: 0.93, 0.98; and for women born in the 1920s-1940s, HR = 0.97, 95% CI: 0.95, 0.99). Further adjustment for adulthood body mass index significantly attenuated the association (HR = 0.99, 95% CI: 0.97, 1.00), especially among those born before 1950 (HR = 1.00, 95% CI: 0.97, 1.02). Much of the inverse association between age at menarche and incident diabetes was mediated through increased adiposity associated with early menarche, especially in older generations.

Epidemiology of Atherosclerosis and the Potential to Reduce the Global Burden of Atherothrombotic Disease.

Atherosclerosis is a leading cause of vascular disease worldwide. Its major clinical manifestations include ischemic heart disease, ischemic stroke, and peripheral arterial disease. In high-income countries, there have been dramatic declines in the incidence and mortality from ischemic heart disease and ischemic stroke since the middle of the 20th century. For example, in the United Kingdom, the probability of death from vascular disease in middle-aged men (35-69 years) has decreased from 22% in 1950 to 6% in 2010. Most low- and middle-income countries have also reported declines in mortality from stroke over the last few decades, but mortality trends from ischemic heart disease have been more varied, with some countries reporting declines and others reporting increases (particularly those in Eastern Europe and Asia). Many major modifiable risk factors for atherosclerosis have been identified, and the causal relevance of several risk factors is now well established (including, but not limited to, smoking, adiposity, blood pressure, blood cholesterol, and diabetes mellitus). Widespread changes in health behaviors and use of treatments for these risk factors are responsible for some of the dramatic declines in vascular mortality in high-income countries. In order that these declines continue and are mirrored in less wealthy nations, increased efforts are needed to tackle these major risk factors, particularly smoking and the emerging obesity epidemic.

Contrasting male and female trends in tobacco-attributed mortality in China: evidence from successive nationwide prospective cohort studies.

BACKGROUND: Chinese men now smoke more than a third of the world's cigarettes, following a large increase in urban then rural usage. Conversely, Chinese women now smoke far less than in previous generations. We assess the oppositely changing effects of tobacco on male and female mortality. METHODS: Two nationwide prospective studies 15 years apart recruited 220,000 men in about 1991 at ages 40-79 years (first study) and 210,000 men and 300,000 women in about 2006 at ages 35-74 years (second study), with follow-up during 1991-99 (mid-year 1995) and 2006-14 (mid-year 2010), respectively. Cox regression yielded sex-specific adjusted mortality rate ratios (RRs) comparing smokers (including any who had stopped because of illness, but not the other ex-smokers, who are described as having stopped by choice) versus never-smokers. FINDINGS: Two-thirds of the men smoked; there was little dependence of male smoking prevalence on age, but many smokers had not smoked cigarettes throughout adult life. Comparing men born before and since 1950, in the older generation, the age at which smoking had started was later and, particularly in rural areas, lifelong exclusive cigarette use was less common than in the younger generation. Comparing male mortality RRs in the first study (mid-year 1995) versus those in the second study (mid-year 2010), the proportional excess risk among smokers (RR-1) approximately doubled over this 15-year period (urban: RR 1·32 [95% CI 1·24-1·41] vs 1·65 [1·53-1·79]; rural: RR 1·13 [1·09-1·17] vs 1·22 [1·16-1·29]), as did the smoking-attributed fraction of deaths at ages 40-79 years (urban: 17% vs 26%; rural: 9% vs 14%). In the second study, urban male smokers who had started before age 20 years (which is now typical among both urban and rural young men) had twice the never-smoker mortality rate (RR 1·98, 1·79-2·19, approaching Western RRs), with substantial excess mortality from chronic obstructive pulmonary disease (COPD RR 9·09, 5·11-16·15), lung cancer (RR 3·78, 2·78-5·14), and ischaemic stroke or ischaemic heart disease (combined RR 2·03, 1·66-2·47). Ex-smokers who had stopped by choice (only 3% of ever-smokers in 1991, but 9% in 2006) had little smoking-attributed risk more than 10 years after stopping. Among Chinese women, however, there has been a tenfold intergenerational reduction in smoking uptake rates. In the second study, among women born in the 1930s, 1940s, 1950s, and since 1960 the proportions who had smoked were, respectively, 10%, 5%, 2%, and 1% (3097/30,943, 3265/62,246, 2339/97,344, and 1068/111,933). The smoker versus non-smoker RR of 1·51 (1·40-1·63) for all female mortality at ages 40-79 years accounted for 5%, 3%, 1%, and <1%, respectively, of all the female deaths in these four successive birth cohorts. In 2010, smoking caused about 1 million (840,000 male, 130,000 female) deaths in China. INTERPRETATION: Smoking will cause about 20% of all adult male deaths in China during the 2010s. The tobacco-attributed proportion is increasing in men, but low, and decreasing, in women. Although overall adult mortality rates are falling, as the adult population of China grows and the proportion of male deaths due to smoking increases, the annual number of deaths in China that are caused by tobacco will rise from about 1 million in 2010 to 2 million in 2030 and 3 million in 2050, unless there is widespread cessation. FUNDING: Wellcome Trust, MRC, BHF, CR-UK, Kadoorie Charitable Foundation, Chinese MoST and NSFC.

Outdoor temperature, blood pressure, and cardiovascular disease mortality among 23 000 individuals with diagnosed cardiovascular diseases from China.

INTRODUCTION: Blood pressure is a major cause of cardiovascular disease (CVD) and both may increase as outdoor temperatures fall. However, there are still limited data about seasonal variation in blood pressure and CVD mortality among patients with prior-CVD. METHODS: We analysed data on 23 000 individuals with prior-CVD who were recruited from 10 diverse regions into the China Kadoorie Biobank during 2004-8. After 7 years of follow-up, 1484 CVD deaths were recorded. Baseline survey data were used to assess seasonal variation in systolic blood pressure (SBP) and its association with outdoor temperature. Cox regression was used to examine the association of usual SBP with subsequent CVD mortality, and seasonal variation in CVD mortality was assessed by Poisson regression. All analyses were adjusted for age, sex, and region. RESULTS: Mean SBP was significantly higher in winter than in summer (145 vs. 136 mmHg, P < 0.001), especially among those without central heating. Above 5°C, each 10°C lower outdoor temperature was associated with 6.2 mmHg higher SBP. Systolic blood pressure predicted subsequent CVD mortality, with each 10 mmHg higher usual SBP associated with 21% (95% confidence interval: 16-27%) increased risk. Cardiovascular disease mortality varied by season, with 41% (21-63%) higher risk in winter compared with summer. CONCLUSION: Among adult Chinese with prior-CVD, there is both increased blood pressure and CVD mortality in winter. Careful monitoring and more aggressive blood pressure lowering treatment in the cold months are needed to help reduce the winter excess CVD mortality in high-risk individuals.

Alcohol and mortality in Russia: prospective observational study of 151,000 adults.

BACKGROUND: Russian adults have extraordinarily high rates of premature death. Retrospective enquiries to the families of about 50,000 deceased Russians had found excess vodka use among those dying from external causes (accident, suicide, violence) and eight particular disease groupings. We now seek prospective evidence of these associations. METHODS: In three Russian cities (Barnaul, Byisk, and Tomsk), we interviewed 200,000 adults during 1999-2008 (with 12,000 re-interviewed some years later) and followed them until 2010 for cause-specific mortality. In 151,000 with no previous disease and some follow-up at ages 35-74 years, Poisson regression (adjusted for age at risk, amount smoked, education, and city) was used to calculate the relative risks associating vodka consumption with mortality. We have combined these relative risks with age-specific death rates to get 20-year absolute risks. FINDINGS: Among 57,361 male smokers with no previous disease, the estimated 20-year risks of death at ages 35-54 years were 16% (95% CI 15-17) for those who reported consuming less than a bottle of vodka per week at baseline, 20% (18-22) for those consuming 1-2·9 bottles per week, and 35% (31-39) for those consuming three or more bottles per week; trend p<0·0001. The corresponding risks of death at ages 55-74 years were 50% (48-52) for those who reported consuming less than a bottle of vodka per week at baseline, 54% (51-57) for those consuming 1-2·9 bottles per week, and 64% (59-69) for those consuming three or more bottles per week; trend p<0·0001. In both age ranges most of the excess mortality in heavier drinkers was from external causes or the eight disease groupings strongly associated with alcohol in the retrospective enquiries. Self-reported drinking fluctuated; of the men who reported drinking three or more bottles of vodka per week who were reinterviewed a few years later, about half (185 of 321) then reported drinking less than one bottle per week. Such fluctuations must have substantially attenuated the apparent hazards of heavy drinking in this study, yet self-reported vodka use at baseline still strongly predicted risk. Among male non-smokers and among females, self-reported heavy drinking was uncommon, but seemed to involve similar absolute excess risks. INTERPRETATION: This large prospective study strongly reinforces other evidence that vodka is a major cause of the high risk of premature death in Russian adults. FUNDING: UK Medical Research Council, British Heart Foundation, Cancer Research UK, European Union, WHO International Agency for Research on Cancer.

Alcohol consumption and mortality: the Khon Kaen Cohort Study, Thailand.

BACKGROUND: The prevalence of alcohol consumption among Thais is high, around 30%. We quantified the relationship between alcohol drinking and mortality in a rural population in the most populous region of Thailand. METHODS: The data were from the Khon Kaen Cohort Study. About 24 000 Thai adults were enrolled between 1990 and 2001, and follow-up for vital status continued until March 16, 2012. Mortality data were obtained from the Bureau of Policy and Strategy, Ministry of the Interior, Thailand. A Cox proportional hazards model was used to analyze the association between alcohol drinking and death, controlling for age, education level, and smoking, and floating absolute risk was used to estimate the 95% confidence intervals of hazard ratios. RESULTS: In total, 18 457 participants (5829 men and 12 628 women) were recruited, of whom 3155 died (1375 men and 1780 women) during a median follow-up period of 13.6 years. Although alcohol drinking was common (64% of men and 25% of women), the amounts consumed were very low (average, 4.3 g/day in men and 0.8 g/day in women). As compared with never drinkers, mortality risk was lower among current drinkers and higher among ex-drinkers. Current drinking was not associated with mortality from cancer or diseases of the circulatory system, although ex-drinkers appeared to have a higher risk of death from the latter. CONCLUSIONS: The leading causes of mortality were not associated with current alcohol drinking at the low consumption levels observed in this population.

Patterns and socio-demographic correlates of domain-specific physical activities and their associations with adiposity in the China Kadoorie Biobank study.

BACKGROUND: Domain-specific physical activities may have different correlates and health effects, but few large studies have examined these questions, especially their separate associations with adiposity. METHODS: We analysed cross-sectional data of 466 605 adults without any prior chronic diseases, enrolled during 2004-8, from 10 diverse localities across China. Physical activity level in each of 4 domains (occupation, commuting, household, and active-recreation), calculated as metabolic equivalent (MET)-hr/day, was related to social-demographic factors and measures of adiposity (body mass index [BMI], waist circumference [WC], and bio-impedance derived percentage body fat), using multivariable linear and logistic regression models. RESULTS: The overall mean age was 50.8 years. The mean total physical activity was 21.7 MET-hr/day, mainly from occupation (62%) and household chores (26%), but little from active-recreation (4%), with women having a much higher household activity than men. Older participants had a lower level of occupational activity but a higher level of household and active-recreational activity, particularly after retirement. There was no linear association of occupational activity with adiposity, but working women tended to have a lower adiposity (e.g. 1.0 cm WC) than non-working women. In men, there was an inverse and apparently linear association between adiposity and levels of both commuting-related and household activities, with 3 MET-hr/day associated with -0.11 and -0.13 kg/m(2) BMI, -0.42 and -0.62 cm WC, and -0.28 and -0.33 percentage points of body fat, respectively. In women, only household activity showed a linear, but weaker, association with adiposity. A higher adiposity was observed among men and women with higher levels of active-recreational activity. CONCLUSIONS: In Chinese adults, physical activity mainly involves occupation and housework, with little from active-recreational activity. Domain-specific physical activities varied by socio-demographic factors and had different associations with adiposity.

Global heterogeneity in folic acid fortification policies and implications for prevention of neural tube defects and stroke: a systematic review.

Background: Folic acid (pteroylmonoglutamic acid) supplements are highly effective for prevention of neural tube defects (NTD) prompting implementation of mandatory or voluntary folic acid fortification for prevention of NTDs. We used plasma folate levels in population studies by country and year to compare effects of folic acid fortification types (mandatory or voluntary folic acid fortification policies) on plasma folate levels, NTD prevalence and stroke mortality rates. Methods: We conducted systematic reviews of (i) implementation of folic acid fortification in 193 countries that were member states of the World Health Organization by country and year, and (ii) estimated population mean plasma folate levels by year and type of folic acid fortification. We identified relevant English language reports published between Jan 1, 1990 and July 31, 2023 using Google Scholar, Medline, Embase and Global Health. Eligibility criteria were observational or interventional studies with >1000 participants. Studies of pregnant women or children <15 years were excluded. Using an ecological study design, we examined the associations of folic acid fortification types with NTD prevalence (n = 108 studies) and stroke mortality rates (n = 3 countries). Findings: Among 193 countries examined up to 31 July 2023, 69 implemented mandatory folic acid fortification, 47 had voluntary fortification, but 77 had no fortification (accounting for 32%, 53% and 15% of worldwide population, respectively). Mean plasma folate levels were 36, 21 and 17 nmol/L in populations with mandatory, voluntary and no fortification, respectively (and proportions with mean folate levels >25 nmol/L were 100%, 15% and 7%, respectively). Among 75 countries with NTD prevalence, mean (95% CI) prevalence per 10,000 population were 4.19 (4.11-4.28), 7.61 (7.47-7.75) and 9.66 (9.52-9.81) with mandatory, voluntary and no folic acid fortification, respectively. However, age-standardised trends in stroke mortality rates were unaltered by the introduction of folic acid fortification. Interpretation: There is substantial heterogeneity in folic acid fortification policies worldwide where folic acid fortification are associated with 50-100% higher population mean plasma folate levels and 25-50% lower NTD prevalence compared with no fortification. Many thousand NTD pregnancies could be prevented yearly if all countries implemented mandatory folic acid fortification. Further trials of folic acid for stroke prevention are required in countries without effective folic acid fortification policies. Funding: Medical Research Council (UK) and British Heart Foundation.

Detection rates of asymptomatic carotid artery stenosis and atrial fibrillation by selective screening of patients without cardiovascular disease.

BACKGROUND: Individuals with significant asymptomatic carotid artery stenosis (ACAS) and atrial fibrillation (AF) could benefit from specific interventions to prevent heart attack and stroke, but are often clinically 'silent'. We aimed to determine detection rate of ACAS and AF by screening, targeting a population at increased cardiovascular risk. METHODS: Data on adults who attended voluntary and self-funded commercial screening clinics in the United States or the United Kingdom between 2008 and 2013 were used. The Atherosclerotic Cardiovascular Disease (ASCVD) risk equation was applied to each participants and detection rates of targeted screening for ≥50% ACAS and AF to those at highest risk of CVD was assessed. RESULTS: Among 0.4 million individuals between 40 and 80 years, without CVD, 6191 (1.6%) had ACAS and 1026 (0.3%) had AF. Selective screening of participants with a predicted 10-year CVD risk of ≥20% identified 40% of ACAS cases, a prevalence of 3.7%, leading to a number needed to screen (NNS) of 27, as well as 39% of AF cases, a prevalence of 0.6%, with a NNS of 170. Selective screening of those with a predicted 10-year CVD risk of ≥15% identified 54% of ACAS cases, a prevalence of 3.3%, and an NNS of 31, as well as 51% of AF cases, a prevalence of 0.5%, with an NNS of 195. CONCLUSIONS: Selective screening for ACAS and AF implemented in ASCVD risk assessment greatly reduces the NNS when compared with population-level screening with detection rates of ACAS and AF substantially greater in people at higher predicted CVD risk.

Independent relevance of adiposity measures to coronary heart disease risk among 0.5 million adults in UK Biobank.

BACKGROUND: Evidence on body fat distribution shows opposing effects of waist circumference (WC) and hip circumference (HC) for coronary heart disease (CHD). We aimed to investigate the causality and the shape of such associations. METHODS: UK Biobank is a prospective cohort study of 0.5 million adults aged 40-69 years recruited between 2006 and 2010. Adjusted hazard ratios (HRs) for the associations of measured and genetically predicted body mass index (BMI), WC, HC and waist-to-hip ratio with incident CHD were obtained from Cox models. Mendelian randomization (MR) was used to assess causality. The analysis included 456 495 participants (26 225 first-ever CHD events) without prior CHD. RESULTS: All measures of adiposity demonstrated strong, positive and approximately log-linear associations with CHD risk over a median follow-up of 12.7 years. For HC, however, the association became inverse given the BMI and WC (HR per usual SD 0.95, 95% CI 0.93-0.97). Associations for BMI and WC remained independently positive after adjustment for other adiposity measures and were similar (1.14, 1.13-1.16 and 1.18, 1.15-1.20, respectively), with WC displaying stronger associations among women. Blood pressure, plasma lipids and dysglycaemia accounted for much of the observed excess risk. MR results were generally consistent with the observational, implying causality. CONCLUSIONS: Body fat distribution measures displayed similar associations with CHD risk as BMI except for HC, which was inversely associated with CHD risk (given WC and BMI). These findings suggest that different measures of body fat distribution likely influence CHD risk through both overlapping and independent mechanisms.

Oxidized phospholipids on apolipoprotein B-100 versus plasminogen and risk of coronary heart disease in the PROCARDIS study.

BACKGROUND AND AIMS: Oxidized phospholipids carried on the apolipoprotein B-100 (OxPL-apoB) component of Lp(a) are predictive of coronary heart disease (CHD), but the role of oxidized phospholipids carried on plasminogen (OxPL-PLG) is unknown. We examined the independent effects of OxPL-apoB and OxPL-PLG for risk of CHD before and after adjustment for Lp(a). METHODS: Plasma levels of OxPL-apoB, OxPL-PLG, plasminogen and Lp(a) were measured in the PROCARDIS study of early-onset CHD (906 cases/858 controls). Multivariable logistic regression was used to estimate the odds ratios (OR) for each biomarker with CHD after adjustment for established risk factors. RESULTS: Mean levels of OxPL-apoB were higher in cases than controls, but levels of OxPL-PLG and plasminogen were similar. For OxPL-apoB, individuals in the top vs bottom fifth had 2-fold higher age and sex-adjusted OR of CHD (OR = 2.61 [95%CI: 1.91, 3.55]), which were partially attenuated after adjustment for established risk factors. The findings for OxPL-apoB and CHD in PROCARDIS were comparable with those of a meta-analysis of all such studies. However, the associations of OxPL-apoB with CHD were fully attenuated by additional adjustment for Lp(a) (OR = 0.93 [0.54,1.60]). Neither OxPL-PLG nor plasminogen were associated with CHD. Overall, there were no differences in the predictive value for CHD of high vs normal levels (<20th or >80th percentile) of OxPL-apoB, OxPL-PLG, plasminogen or Lp(a) after stratifying for each other. CONCLUSIONS: These results highlight the context-dependency of OxPL in plasma and suggest that their associated risk of CHD is chiefly mediated by their carriage on Lp(a).

Reproductive factors and gall-bladder cancer, and the effect of common genetic variants on these associations: a case-control study in India.

BACKGROUND: In India, as elsewhere, the incidence of gall-bladder cancer (GBC) is substantially higher in women than in men. Yet, the relevance of reproductive factors to GBC remains poorly understood. METHODS: We used logistic regression adjusted for age, education and area to examine associations between reproductive factors and GBC risk, using 790 cases of histologically confirmed GBC and group-matched 1726 visitor controls. We tested the interaction of these associations by genetic variants known to increase the risk of GBC. RESULTS: Parity was strongly positively associated with GBC risk: each additional pregnancy was associated with an ∼25% higher risk {odds ratio [OR] 1.26 [95% confidence interval (95% CI) 1.17-1.37]}. After controlling for parity, GBC risk was weakly positively associated with later age of menarche [postmenopausal women, OR 1.11 (95% CI 1.00-1.22) per year], earlier menopause [OR 1.03 (95% CI 1.00-1.06) per year] and shorter reproductive lifespan [OR 1.04 (95% CI 1.01-1.07) per year], but there was little evidence of an association with breastfeeding duration or years since last pregnancy. Risk alleles of single-nucleotide polymorphisms in the ABCB4 and ABCB1 genetic regions had a multiplicative effect on the association with parity, but did not interact with other reproductive factors. CONCLUSIONS: We observed higher GBC risk with higher parity and shorter reproductive lifespan, suggesting an important role for reproductive and hormonal factors.

Educational inequalities and premature mortality: the Cuba Prospective Study.

BACKGROUND: Although socioeconomic status is a major determinant of premature mortality in many populations, the impact of social inequalities on premature mortality in Cuba, a country with universal education and health care, remains unclear. We aimed to assess the association between educational level and premature adult mortality in Cuba. METHODS: The Cuba Prospective Study (a cohort study) enrolled 146 556 adults aged 30 years and older from the general population in five provinces from Jan 1, 1996, to Nov 24, 2002. Participants were followed up until Jan 1, 2017, for cause-specific mortality. Deaths were identified through linkage to the Cuban Public Health Ministry's national mortality records. Cox regression models yielded rate ratios (RRs) for the effect of educational level (a commonly used measure for social status) on mortality at ages 35-74 years, with assessment for the mediating effects of smoking, alcohol consumption, and BMI. FINDINGS: A total of 127 273 participants aged 35-74 years were included in the analyses. There was a strong inverse association between educational level and premature mortality. Compared with a university education, men who did not complete primary education had an approximately 60% higher risk of premature mortality (RR 1·55, 95% CI 1·40-1·72), while the risk was approximately doubled in women (1·96, 1·81-2·13). Overall, 28% of premature deaths could be attributed to lower education levels. Excess mortality in women was primarily due to vascular disease, while vascular disease and cancer were equally important in men. 31% of the association with education in men and 18% in women could be explained by common modifiable risk factors, with smoking having the largest effect. INTERPRETATION: This study highlights the value of understanding the determinants of health inequalities in different populations. Although many major determinants lie outside the health system in Cuba, this study has identified the diseases and risk factors that require targeted public health interventions, particularly smoking. FUNDING: UK Medical Research Council, British Heart Foundation, Cancer Research UK, CDC Foundation (with support from Amgen).

Discovery and systematic characterization of risk variants and genes for coronary artery disease in over a million participants.

The discovery of genetic loci associated with complex diseases has outpaced the elucidation of mechanisms of disease pathogenesis. Here we conducted a genome-wide association study (GWAS) for coronary artery disease (CAD) comprising 181,522 cases among 1,165,690 participants of predominantly European ancestry. We detected 241 associations, including 30 new loci. Cross-ancestry meta-analysis with a Japanese GWAS yielded 38 additional new loci. We prioritized likely causal variants using functionally informed fine-mapping, yielding 42 associations with less than five variants in the 95% credible set. Similarity-based clustering suggested roles for early developmental processes, cell cycle signaling and vascular cell migration and proliferation in the pathogenesis of CAD. We prioritized 220 candidate causal genes, combining eight complementary approaches, including 123 supported by three or more approaches. Using CRISPR-Cas9, we experimentally validated the effect of an enhancer in MYO9B, which appears to mediate CAD risk by regulating vascular cell motility. Our analysis identifies and systematically characterizes >250 risk loci for CAD to inform experimental interrogation of putative causal mechanisms for CAD.

Association of cognitive impairment with combinations of vitamin B12-related parameters.

BACKGROUND: Low vitamin B12 concentrations have been associated with higher risks of cognitive impairment, but whether these associations are causal is uncertain. The associations of cognitive impairment with combinations of vitamin B12, holotranscobalamin, methylmalonic acid, and total homocysteine, and with the vitamin B12 transport proteins transcobalamin and haptocorrin, have not been previously studied. METHODS: We performed a population-based cross-sectional study of 839 people 75 years old or older. We examined the association of cognitive function as measured by mini-mental state examination scores, with markers of vitamin B12 status. Spearman correlations as well as multivariate-adjusted odds ratios and 95% CIs for cognitive impairment were calculated for extreme thirds of serum concentrations of vitamin B12, holotranscobalamin, methylmalonic acid, total homocysteine, combination of these markers in a wellness score, heaptocorrin, and transcobalamin for all data and with B12 analogs in a nested case-control study. RESULTS: Cognitive impairment was significantly associated with low vitamin B12 [odds ratio 2.3 (95% CI 1.2-4.5)]; low holotranscobalamin [4.1 (2.0-8.7)], high methylmalonic acid [3.5 (1.8-7.1)], high homocysteine [4.8 (2.3-10.0)] and low wellness score [5.1 (2.61-10.46)]. After correction for relevant covariates, cognitive impairment remained significantly associated with high homocysteine [4.85 (2.24-10.53)] and with a low wellness score [5.60 (2.61-12.01)] but not with transcobalamin, haptocorrin, or analogs on haptocorrin. CONCLUSIONS: Cognitive impairment was associated with the combined effects of the 4 biomarkers of vitamin B12 deficiency when included in a wellness score but was not associated with binding proteins or analogs on haptocorrin.