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Summary Background Milk as a common diet is recommended by many guidelines, but the results on the association of milk consumption with the risk of cardiovascular disease (CVD) or cancer were contradictory. Moreover, evidence regarding milk consumption and mortality risk in Chinese is scarce. Objective We examined the associations of milk consumption with the risk of all-cause, CVD and cancer mortality in a low milk consumption population using data from the Guangzhou Biobank Cohort Study. Design 18,214 participants aged 50+ years without CVD history at baseline (2003–6) were included. Causes of death were identified through record linkage. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Results Of the 18,214 participants, 12,670 (69.6%) did not consume milk, 2669 (14.7%) had moderate (1–3 portions/week; 1 portion = 250 ml) and 2875 (15.8%) had high (3+ portions/week) consumption. During an average follow-up of 11.5 (standard deviation = 2.3) years, 2697 deaths occurred, including 917 CVD and 1029 cancer deaths. Compared with no consumption, the adjusted HR (95% CIs) of all-cause, CVD, ischemic heart disease (IHD) and stroke mortality for moderate milk consumption was 0.92 (0.81–1.04), 0.72 (0.57–0.92), 0.57 (0.38–0.85) and 0.77 (0.63–0.94), respectively. High consumption was associated with a higher risk of total cancer and esophagus cancer mortality, with the adjusted HR (95% CIs) being 1.33 (1.12–1.57) and 3.20 (1.21–8.43) respectively. No significant association of high consumption with lung cancer, liver cancer, gastrointestinal cancer, or colorectal and anal cancer was found. Conclusions In our sample of Chinese with much lower milk consumption than those in the West, compared with no consumption, moderate milk consumption showed a lower risk of CVD mortality, but high milk consumption showed a higher risk of total cancer mortality. Further studies are warranted to verify the differential effects of milk on CVD and cancer.

Background: Evidence regarding the association of low-carbohydrate diet (LCD) with the risk of stroke is limited. We examined the associations of LCD with the risk of stroke in a population with relatively high carbohydrate intake and risk of stroke, and updated the evidence using meta-analysis. Methods: 19,850 participants aged 50+ years without stroke history at baseline (2003-6) in the Guangzhou Biobank Cohort Study were included. Low-carbohydrate-diet score was calculated based on the percentage of energy from carbohydrate, protein and fat, with higher score indicating a lower intake of carbohydrate and a higher intake of fat and protein. Three categories: total, animal-based, and vegetable-based LCD score including seven subtypes of LCD scores were created. Findings: During an average follow-up of 13·1 (standard deviation=2·5) years, 1,661 stroke events and deaths occurred, including 1,255 ischaemic strokes. Increasing “total LCD” and three “animal-based LCDs” scores were marginally non-significantly associated with a lower risk of stroke, while increasing three “vegetable-based LCDs” scores were not significantly associated with a lower risk of all stroke. The adjusted HR (95% CI) of all stroke and ischaemic stroke was 0·91 (0·79-1.05) and 0·90 (0·77-1·06) for the highest versus the lowest quartile of “total LCD” scores, and 0·89 (0·78-1·03) and 0·89 (0·76-1·04) for the highest versus the lowest quartile of “animal LCD” scores, respectively. Moreover, inverse associations with all stoke and ischaemic stroke in the second versus the lowest quartile of “animal LCD” scores were found, with the HR (95% CI) being 0·87, (0·77-0·997) and 0·83 (0·72-0·97), respectively. In addition, inverse associations with all stoke and ischaemic stroke both in the second and third versus the lowest quartile of “animal low-bad-carbohydrate-diet” scores were also found, with the HR (95% CI) being 0·83 (0·73-0·95) and 0·77 (0·66-0·90) in the second quartile , and 0·87 (0·76-0·99) and 0·83 (0·71-0·96) in the third quartile, respectively. A meta-analysis including 149,493 participants and 5,639 strokes found marginally non-significant association of the highest versus the lowest category of carbohydrate intake with higher risks of all stroke (pooled HRs 1·10, 95% CI 0·96-1·26). Interpretation: In a population which consumed a relatively high level of carbohydrate and low level of protein and fat, diets lower in carbohydrate, higher in animal protein and low-to-moderate in saturated fat, but not higher in vegetable protein and unsaturated fat, were associated with a lower risk of stroke. Funding Statement: The University of Hong Kong Foundation for Educational Development and Research, the Health Medical Research Fund in Hong Kong; the Guangzhou Public Health Bureau and the Guangzhou Science and Technology Bureau; Natural Science Foundation of Guangdong, Natural Science Foundation of China and the University of Birmingham, UK. Declaration of Interests: The authors declare that they have no conflict of interest.

Observational studies show earlier age at menarche associated with higher risk of cardiovascular disease although these studies could be confounded by childhood obesity or childhood socioeconomic position. We tested the hypothesis that earlier age at menarche is associated with poorer cardiovascular risk factors using a Mendelian randomization design. We conducted a Mendelian randomization study in a large Southern Chinese cohort, the Guangzhou Biobank Cohort Study (n = 12,279), to clarify the causal role of menarche in cardiovascular disease risk factors including blood pressure, lipids, fasting glucose, adiposity and type 2 diabetes. A genetic allele score was obtained from single nucleotide polymorphisms associated with age at menarche using stepwise regression and with cross validation. Estimates of the association of age at menarche with cardiovascular disease risk factors were obtained using two stage least squares regression. Height was included as a positive control outcome. The F-statistic for the allele score (rs17268785, rs1859345, rs2090409, rs4452860 and rs4946651) was 19.9. Older age at menarche was associated with lower glucose (− 0.39 mmol/L per year older menarche, 95% confidence interval (CI) − 0.78 to − 0.001) but not clearly with any other cardiovascular risk factors. Older age at menarche was also associated with taller height. Age at menarche did not appear to affect cardiovascular disease risk factors except for glucose in an inverse manner. However, these results need to be confirmed in larger Mendelian randomization studies.

Objective The role of estrogen in cognitive function and depressive symptoms is controversial due to discrepancies between results from randomized controlled trials (RCT) and observational studies. Mendelian randomization analysis may provide further insights concerning the role of estrogen in these outcomes as it assesses the effect of lifelong endogenous exposure but is less vulnerable to confounding than observational studies. Method We used separate sample instrumental variable analysis to estimate the association of log 17β estradiol with cognitive function (Delayed 10 word recall, and Mini Mental State Examination (MMSE)) and depressive symptoms (Geriatric Depression Scale (GDS)) in older Chinese women of the Guangzhou Biobank Cohort Study (GBCS, n = 3086). The estimate was derived based on the Wald estimator, the ratio of the association of genetic determinants (rs1008805 and rs2175898) of log 17β-estradiol with cognitive function and depressive symptoms in GBCS and the association of log 17β-estradiol with genetic determinants in the sample of young women in Hong Kong (n = 236). Results Genetically predicted 17β-estradiol was not associated with delayed 10-word recall (0.42 words per log increase in 17β-estradiol (pmol/L), 95% confidence interval (CI) − 0.49 to 1.34) MMSE (0.39 per log increase in 17β-estradiol (pmol/L), 95% CI − 0.87 to 1.65) or GDS (0.24 per log increase in 17β-estradiol (pmol/L), 95% CI − 0.57 to 1.05). Conclusion These results were largely consistent with evidence from RCTs and did not show any beneficial effect of estrogen on cognitive function and depressive symptoms. However, larger Mendelian randomization analyses are needed to identify any minor effects.

Purpose The role of estrogen in cardiovascular health remains contested with discrepancies between findings from randomized controlled trials and observational studies. Mendelian randomization, which assesses the effect of lifelong endogenous exposure, may help elucidate these discrepancies. Methods We used separate sample instrumental variable analysis to estimate the association of log 17β-estradiol with factors related to cardiovascular disease risk (systolic and diastolic blood pressure, lipids, fasting glucose, body mass index, waist hip ratio, and waist circumference) and Framingham score, a predictor of 10-year risk of ischemic heart disease events, in older Chinese women from the Guangzhou Biobank Cohort Study (GBCS, n = 3092). The estimate was derived using the Wald estimator, that is, the ratio of the association of genetic determinants (rs1008805 and rs2175898) of log 17β-estradiol with cardiovascular disease risk factors and Framingham score in GBCS and the association of these genetic determinants with log 17β-estradiol in a sample of young women from Hong Kong (n = 236). Results Genetically, higher 17β-estradiol was not associated with any cardiovascular disease-related risk factor or with Framingham score (−0.01, 95% confidence interval = −1.34 to 1.31). Conclusions Lifetime exposure to estrogen does not appear to be cardioprotective via the cardiovascular disease-related risk factors examined.

Objective: To study whether spirometry respiratory disorders with and without dyspnea were associated with mortality in older Chinese. Methods: Guangzhou Biobank Cohort Study participants were classified by respiratory patterns and presence of dyspnea into 6 groups: normal spirometry (NS), airflow obstruction (AO) and restrictive respiratory pattern (RRP) with and without dyspnea (dyspnea defined by British modified Medical Research Council scale ≥2). Adjusted hazard ratios (aHRs) were calculated using Cox models. Results: In all 16377 subjects, the increased mortality risk from AO was greater for all-cause (aHR 1.72 (95% confidence interval (CI) 1.49-2.00) vs. 1.46 (95% 1.29-1.65)) but lower for cardiovascular diseases (aHR 1.47 (95% CI 1.12-1.92) vs. 1.77 (95% CI 1.46-2.14)) than from RRP. Only AO was associated with lung cancer mortality (aHR 2.22 (95% CI 1.53-3.24)) (all P values 0.27), all the other aHRs were similar in those with and without dyspnea (aHRs ranged from 1.43 to 3.99, P values

Purpose In Asia, moderate alcohol users have better lung function. Never users have more inactive aldehyde dehydrogenase 2 (ALDH2) alleles (A) potentially generating confounding because inactive alleles may increase acetaldehyde exposure and reduce lung function. Methods We examined the association of ALDH2 genotypes with percentage predicted lung function (forced expiratory volume in 1 second; forced vital capacity) for age, sex, and height among 5641 older Chinese using multivariable linear regression. Results ALDH2 genotypes were associated with alcohol use and height but not other attributes. Inactive alleles were inversely associated with lung function (percentage predicted forced expiratory volume in 1 second −1.52%, 95% confidence interval [CI], −2.52% to −0.51% for one inactive allele and −2.05%, 95% CI, −3.85% to −0.26% for two inactive alleles compared with two active alleles; and for percentage predicted forced vital capacity −1.25%, 95% CI −2.15% to −0.35% and −1.65%, 95% CI, −3.25% to −0.04%). The association of moderate use with lung function was attenuated after adjusting for ALDH2, in addition to other potential confounders. Conclusions Previous findings in Chinese may be confounded by ALDH2. High frequency of inactive ALDH2 alleles in East Asia may exacerbate the effect of environmental acetaldehyde exposure on lung function and potentially on chronic obstructive pulmonary disease.

To examine the association between serum uric acid (UA) levels and cardiovascular risk factors in subjects without diabetes or hyperuricemia.6172 women and 2662 men aged 50+ years without diabetes from Phase 1 of the Guangzhou Biobank Cohort Study were included. Data on personal history, physical examination and biochemical parameters were collected. Subjects were categorized by serum UA concentration, and the association between UA levels and cardiovascular risk factors was examined using generalized linear models.In both men and women with normouricemia (UA420 μmol/l in men and360 μmol/l in women), tertiles of UA levels were adversely associated with body mass index, waist circumference, waist-to-hip ratio, total- and HDL-cholesterol, apolipoprotein A1, systolic and diastolic blood pressures, pulse pressure, fasting plasma glucose and white blood cell count (P value for trend ranged from 0.04 to0.001), and also consistently associated with metabolic disorders including obesity, hypertension, hypertension treatment, dyslipidemia, waist circumference increased since the age of 18 years and the metabolic syndrome (P value for trend ranged from 0.02 to0.001).Increasing UA levels, even in subjects with normouricemia and without diabetes, were associated with increasing prevalence of cardiovascular risk factors, suggesting that clinically dichotomous definition of hyperuricemia may be inadequate and high-normal value of UA may warn of metabolic disorders.

Chinese people have a markedly lower alcohol consumption than people in the West. Whether alcohol consumption at such levels is associated with left ventricular hypertrophy, and the role of blood pressure (BP) in this relationship is unclear. We investigated the association between alcohol consumption and electrocardiographic left ventricular hypertrophy (ECG-LVH) and the mediating role of BP in Chinese men aged ≥50 years.A case-control analysis was conducted on baseline cross-sectional data from the community-based Guangzhou Biobank Cohort Study (2003-2008), using standard 12-lead resting electrocardiograms. By comparing 191 new ECG-LVH cases with 4311 controls, excessive drinking (210 g/week) showed excess risks for ECG-LVH (odds ratio [OR] = 1.90, 95% confidence interval [CI] = 1.12-3.24), after adjusting for education, income, occupation, physical activity, smoking, body mass index, fasting glucose, triglyceride, total cholesterol, high-density lipoprotein cholesterol, BP, and antihypertensive medication. Mediation analysis showed a significant mediating effect of BP on the association between excessive drinking and ECG-LVH: systolic (31%) and diastolic (16%). After multivariate adjustment, no significant association was found between occasional drinking (once/week: OR = 1.20, 95% CI = 0.80-1.80) and moderate drinking (≥once/week to ≤210 g/week: OR = 0.88, 95% CI = 0.53-1.47) with increased/decreased risk of ECG-LVH.Alcohol consumption at210 g/week in Chinese men is an independent risk factor for ECG-LVH. Low power prevented us from examining whether drinking atonce/week to ≤210 g/week is associated with decreased/increased risk of ECG-LVH. Elevated BP partially mediates between alcohol and ECG-LVH. A Mendelian randomization approach with a large sample size is warranted to determine the relations among alcohol consumption, BP, and LVH.

Objective To examine the association between alcohol consumption and aortic arch calcification (AAC) in an older Chinese sample. Methods In 27,844 older people aged 50–85, socioeconomic position and lifestyle factors were assessed by a questionnaire. The presence and severity of AAC were diagnosed from chest X-ray by two experienced radiologists. Results In men, the risk for AAC increased significantly in frequent or excessive drinkers [adjusted odds ratio (OR)=1.36 (95% confidence interval (CI) 1.16–1.59) and 1.49 (1.21–1.83) for those who drank >5times/week and those who drank excessively, respectively] (P for trend from 0.002 to 0.001). When AAC was analyzed as an outcome variable with 3 categories of severity, significant dose–response relations between the severity of AAC and alcohol consumption were observed, with those who drank frequently (>5/week) or excessively having more serious AAC (P for trend=0.03 and 0.02, respectively). No significant association was found in women as few drank excessively. Conclusion The presence and severity of AAC were associated with quantity or frequency of alcohol consumption in a dose–response pattern, suggesting that alcohol drinking, even when moderate, has no benefit for AAC. Excessive drinking increased the risk of AAC by 50% compared to never drinkers.

Summary The impact of occupational dust and gas/fume exposure on chronic obstructive pulmonary disease (COPD) in developing countries has not been quantified. We examined the relationship between past dust and fume exposure and prevalence of COPD and respiratory symptoms in a cross-sectional analysis of a large Chinese population sample. Participants in the Guangzhou Biobank Cohort Study ( n = 8216; 27.3% men, mean age 61.9 ± 6.8 years) had spirometry and a structured interview including exposures, symptoms, and lifestyle. Self-reported intensity and duration of dust and gas/fume exposure was used to derive cumulative exposure. COPD was diagnosed from spirometry using lower limit of normal based on prediction equations. COPD was associated with high exposure to dust or gas/fume (exposed: 87/1206 v non-exposed: 191/3853; adjusted odds ratio: 1.41; 95% confidence interval (CI) 1.06, 1.87) with no evidence of effect modification by smoking. Respiratory symptoms were associated with exposures to dust and gas/fume, with adjusted odds ratios for chronic cough/phlegm of 1.57 (1.13, 2.17) and 1.39 (1.20, 1.60) for dyspnoea. The overall population attributable fraction for COPD due to occupational exposure was 10.4% (95% CI -0.9%, 19.5%). Occupational dust and gas/fume exposure is associated with an increased prevalence of COPD in this Chinese sample, independent of smoking. The population attributable fraction in Chinese is similar to that in Western populations.

To examine, via cross-sectional analysis, the dose-response association between physical activity and cognitive function in Chinese subjects.A total of 27,651 participants aged 50 to 85 years were recruited from 2003 to 2008. Information on potential confounders, including demographic and anthropometric characteristics, socioeconomic position, lifestyle, and disease history, was collected by standardized interview and procedures. Cognitive function was assessed by the delayed 10-word recall test (DWRT).When the International Physical Activity Questionnaire was used, we found that most of the participants were classified as physically active (53.1%), with 42.4% moderately active and 4.5% physically inactive. Significant dose-response relations across quintiles of metabolic equivalent value (METs) with DWRT score in participants with or without good self-rated health were found (all p for trend.001). In participants with poor self-rated heath, compared with the first quintile of METs, those in the fifth quintile (highest METs) had a significantly reduced risk for mild cognitive impairment by 28% (adjusted odds ratio, 0.72; 95% confidence interval, 0.58-0.89, p.01; p for trend = .006). After additional adjustment for depression, we found that the association between physical activity and DWRT score remained significant.A significant dose-response relationship between physical activity and cognitive function was found, and the association was more pronounced in participants with poor self-rated health.

Objective To study whether passive smoking is a risk factor for aortic arch calcification (AAC) among never smokers. Background We have previously reported that active smoking increases the risk of AAC, but the effect of passive smoking has not been reported. Methods We used baseline data of the Phase 1 Guangzhou Biobank Cohort Study (GBCS). 7702 older Chinese never smokers from the Phase 1 GBCS were included. Information on passive smoking and potential confounders were collected by standardized interviews and laboratory assays. AAC was diagnosed from chest X-ray by two experienced radiologists. Unconditional logistic regression was used to estimate odds ratios of AAC for passive smoking with adjustment for potential confounders. Results In women, the risk for aortic arch calcification (AAC) increased significantly with increasing duration of adulthood passive smoking exposure at home, at work and total duration of adulthood home and work exposure [adjusted odds ratio 1.24 (95% confidence interval 1.09–1.41) for high level of total exposure] ( P for trend from 0.012 to 0.001). For passive smoking at home, at work and total exposure, significant trends of increasing severity of AAC with increasing duration of exposure were observed in men and women combined ( P for trend from 0.05 to 0.002). Conclusion Passive smoking is a risk factor for aortic arch calcification. Studies of passive smoking and AAC, especially in developing countries can generate important local evidence to raise awareness and to support public health measures to protect non-smokers from second-hand smoke.

Purpose With economic development, there is an emerging epidemic of diabetes in China despite relatively low levels of obesity. Muscle mass, for which adolescence is a key developmental window, may reduce vulnerability to diabetes. We examined the association of recalled adolescent build with diabetes in a large sample from the developing country setting of southern China. Methods We used multivariable regression in cross-sectional data (2005–2008), from the Guangzhou Biobank Cohort Study (phases 2 and 3) for 19,524 older (≥50 years) Chinese to examine the adjusted associations of recalled adolescent relative weight (light [ n = 6843], average [ n = 9529], and heavy [ n = 3152]) with clinically measured diabetes. Results As older adults, heavy adolescents had a lower risk of diabetes (odds ratio = 0.86, 95% confidence interval: 0.75–0.99) than light adolescents adjusted for age, sex, education, smoking, leg length, and seated height. This association was stronger after additional adjustment for waist/hip ratio and body mass index. Conclusions Poor living conditions during adolescence, resulting in low muscle mass, could contribute to vulnerability to diabetes, which, if confirmed, could be relevant to the emerging epidemic of diabetes in the developing world, as well as to minorities and migrants elsewhere.

Purpose Women usually report attributes of masculinity as attractive. These are attributes are metabolically expensive. We examined the trade off of a key attribute of masculinity, muscularity, proxied by recalled adolescence build, with lifetime reproductive success in the developing country setting of Southern China. Methods We used poisson multivariable regression in 19,168 older (≥50 years) Chinese from the Guangzhou Biobank Cohort Study (phases 2 and 3) to examine the sex-stratified, adjusted associations of recalled adolescent relative weight (light ( n = 6730), average ( n = 9344), and heavy ( n = 3094)) with number of offspring. Results Among men, recalled heavy adolescent weight compared with light was associated with an incident rate ratio for offspring of 1.08 (95% confidence interval [CI] 1.04–1.13) adjusted for age. This estimate was unchanged by adjustment for life course socio-economic position. There was no such association in women. Conclusions Male physical attractiveness, possibly representing levels of testosterone, was rewarded by lifetime reproductive success, despite potential costs. Socio-economic development may facilitate an inevitable move toward environmentally driven higher levels of testosterone with corresponding public health implications for any conditions or societal attributes driven by testosterone. Further investigation is warranted.

Purpose Earlier pubertal maturation in women may be associated with better cognition. It is unclear whether or not this also occurs in men. We tested the hypothesis that earlier pubertal development in men was associated with better cognition in later adulthood in a developing Chinese population. Methods Multivariable linear regression was used in cross-sectional study of 2463 older, Chinese men from the Guangzhou Biobank Cohort Study. Mean pubertal age was calculated as the mean of recalled ages of first nocturnal emission, voice breaking and pubarche. We assessed the association of mean pubertal age with delayed 10-word recall and mini-mental state examination (MMSE) scores. Results Adjusted for age and education, 1 year earlier mean pubertal age was associated with higher delayed 10-word recall (0.06 [95% confidence interval = 0.02–0.10]) and higher MMSE (0.08 [0.03–0.13]) scores. Additional adjustment for childhood and adulthood socio-economic position, sitting height, and leg length did not change the results. Conclusions These preliminary findings suggest earlier maturation in men is associated with better cognitive function in later adulthood. Whether pubertal timing is a marker of earlier life exposures or reflects a biological relation between somatrophic and/or gonadotrophic hormones and cognitive development is unclear.

SummaryBackgroundabitual snoring and elevated high-sensitive C-reactive protein (HsCRP) have both been associated with increased risk of cardiovascular disease. However, snoring and HsCRP are elevated in obese states which may thus be the primary determinant of both. We therefore investigated whether snoring may mediate the increased vascular risk directly through increased inflammation as indicated by HsCRP levels or if other determinants predominated in a large older Chinese population.MethodsA total of 2508 males and 5709 females aged 50–85 years received a medical check-up including measurement of blood pressure, obesity indices, fasting total, LDL-, HDL-cholesterol, triglycerides, glucose and HsCRP. Information on self-reported snoring status was collected by standardized interview.ResultsThe age-adjusted geometric mean HsCRP concentrations increased significantly with higher snoring frequency in both genders (linear trend, p=0.02 for men and p

Background Prior pulmonary TB has been shown to be associated with a higher risk of airflow obstruction, which is the hallmark of COPD, but whether smoking modifies this relationship is unclear. We investigated the relationships between prior TB, smoking, and airflow obstruction in a Chinese population sample. Methods Participants in the Guangzhou Biobank Cohort Study underwent spirometry, chest radiography, and a structured interview on lifestyle and exposures. Prior TB was defined as the presence of radiologic evidence suggestive of inactive TB. Airflow obstruction was based on spirometric criteria. Results The prevalence of prior TB in this sample (N = 8,066, mean age: 61.9 years) was 24.2%. After controlling for sex, age, and smoking exposure, prior TB remained independently associated with an increased risk of airflow obstruction (odds ratio=1.37; 95% CI, 1.13-1.67). Further adjustment for exposure to passive smoking, biomass fuel, and dust did not alter the relationship. Smoking did not modify the relationship between prior TB and airflow obstruction. Conclusions Prior TB is an independent risk factor for airflow obstruction, which may partly explain the higher prevalence of COPD in China. Clinicians should be aware of this long-term risk in individuals with prior TB, irrespective of smoking status, particularly in patients from countries with a high TB burden.

The aim of the study was to compare the impact of impaired fasting glucose (IFG) and impaired glucose tolerance (IGT) on vascular function among older Chinese people. A random sample of 671 men and 603 women aged 50 to 85 years without known diabetes from the Guangzhou Biobank Study-CVD was examined in a cross-sectional study. Subjects with no previously confirmed or treated diabetes but with both fasting plasma glucose less than 5.6 mmol/L and 2-hour glucose from 7.8 to less than 11.0 mmol/L were classified as having isolated IGT, and those with no previously confirmed and treated diabetes but with both fasting plasma glucose from 5.6 to less than 7.0 mmol/L and 2-hour glucose less than 7.8 mmol/L were classified as having isolated IFG. A total of 11.0% of the men and 8.6% of the women had isolated IFG, and 17.7% of the men and 18.6% of the women had isolated IGT. The brachial-ankle pulse wave velocity and pulse pressure were increased in both the isolated IFG and isolated IGT subjects compared with the normoglycemia group (both Ps.001). Compared with subjects with isolated IFG, those with isolated IGT appeared to have a higher age- and sex-adjusted brachial-ankle pulse wave velocity (1543 +/- 22 vs 1566 +/- 17, P = .07) and to be more insulin resistant (2-hour postload insulin: 54.2 +/- 2.13 vs 26.8 +/- 2.99 muU/mL, P.001), had a worse lipid profile (apolipoprotein [apo] B: 1.07 +/- 0.02 vs 0.97 +/- 0.02 g/L, P.001; apo B/apo A-1 ratio: 0.80 +/- 0.02 vs 0.69 +/- 0.02, P.001), but had lower glycosylated hemoglobin levels (6.03% +/- 0.06% vs 5.86% +/- 0.04%, P.001) (values are mean +/- SE). Subjects with isolated IGT had greater arterial stiffness, probably as a result of being more insulin resistant, with a worse lipid profile than those with isolated IFG. The sole use of fasting glucose level to identify prediabetic people would fail to identify a significant proportion of the at-risk population.

To study the association between smoking, smoking cessation and aortic arc calcification (AAC) in an older Chinese population.A total of 3022 men and 7279 women aged 50-85 years were recruited and received a medical check-up including measurement of fasting plasma vascular risk factors. Two radiologists reviewed the posterior-anterior plain chest X-ray radiographs and assessed AAC together. Information on smoking status, socioeconomic and lifestyle factors was collected.The crude prevalence of AAC in men (38.58%) was lower than that in women (41.37%). The adjusted odds ratios of AAC increased significantly across never, ex- and current smokers in both genders. Dose-response relationships were observed among current smokers for smoking amount (cigarettes/day), smoking duration (years) and cigarette pack-years in both genders (all p0.01). The odds ratios decreased significantly (p=0.018) with longer duration of quitting in light ex-smoking men (23.5 pack-years) but showed no beneficial effect (p=0.72) for heavy ex-smokers (or=23.5 pack-years).Smoking increased the risk of AAC in Chinese, while smoking cessation decreased the risk only in male light ex-smokers. Chest X-ray is a cheap and simple method to detect AAC, which should be an important warning signal for immediate smoking cessation.

Hyperglycemia increases cardiovascular disease risk, but the association between increasing glycemia and cardiovascular risk factors, angina, and coronary heart disease in normoglycemic subjects is less clear, particularly in Chinese. We report on possible associations in a large group of Mainland Chinese subjects. A total of 10,400 older subjects (> or = 50 years) were recruited, and vascular risk factors were measured, including anthropometry, blood pressure, and fasting plasma biochemical factors including glucose, lipid profile, and C-reactive protein (CRP). Subjects were categorized by glycemic status, and the relationship between glycemia and cardiovascular risk factors was investigated using analysis of variance and multiple linear regression analyses. Tertiles of fasting glucose levels showed a clear positive relationship with cardiovascular risk factors including age, obesity, blood pressure, lipid levels, and CRP (P < .001 for all). The overall prevalence of self-reported vascular disease was low, but significantly associated with increasing glycemia. Multiple regression showed that waist circumference (standardized regression coefficient beta = .10, P < .001), triglycerides (beta = 0.16, P < .001), CRP (beta = 0.06, P < .001), female sex (beta = .03, P = .007), high-density lipoprotein cholesterol (beta = -.02, P = .016), and mean arterial pressure (beta = .06, P < .001) were independently associated with fasting glucose levels. Among the normoglycemic subjects (n = 5190), increasing glycemia was still associated with increasing obesity indices, systolic blood pressure, triglyceride, and CRP levels (all P < .05). Increasing glycemia, even in the reference range, is associated with increasing prevalence of vascular risk factors. Control of these risk factors, particularly obesity, the most important avoidable independent determinant of glycemia in normoglycemic subjects, is critical to reduce the risk of the associated vascular disease.

Purpose In randomized controlled trials reducing high hematocrit (Hct) in patients with polycythemia vera protects against cardiovascular disease (CVD) events, whereas increasing Hct in anemia patients causes CVD events. Hct is influenced by environmental and lifestyle factors. Given limited knowledge concerning the drivers of Hct, we took an agnostic approach to identify drivers of Hct. Methods We used an environment-wide association study to identify environmental and lifestyle factors associated with Hct in 20443 older Chinese adults (mean age = 62.7 years) from the Guangzhou Biobank Cohort Study. We evaluated the role of 25 nutrients, 40 environmental contaminants, two metals (only available for 10405 participants), and six lifestyle factors in relation to Hct, adjusted for sex, age, recruitment phase, and socioeconomic position. Results In a mutually adjusted model vitamin A, serum calcium, serum magnesium, and alcohol use were associated with higher Hct, whereas physical activity was associated with lower Hct. Conclusions Despite the difficulty of ascertaining causality, finding both expected (vitamin A and physical inactivity) and novel factors (serum calcium, serum magnesium and alcohol use) strongly associated with Hct illustrates the utility of environment-wide association study to generate hypotheses regarding the potential contribution of modifiable exposures to CVD.

Cognitive decline is a reduction in cognitive ability usually associated with aging, and those with more extreme cognitive decline either have or are at risk of progressing to mild cognitive impairment and dementia including Alzheimer's disease (AD). We hypothesized that genetic variants predisposing to AD should be predictive of cognitive decline in elderly individuals. We selected 1325 subjects with extreme cognitive decline and 1083 well-matched control subjects from the Guangzhou Biobank Cohort Study in which more than 30,000 southern Chinese older people have been recruited and followed up. Thirty single-nucleotide polymorphisms in 29 AD-associated genes were genotyped. No statistically significant allelic associations with cognitive decline were found by individual variant analysis. At the level of genotypic association, we confirmed that the APOE ε4 homozygote significantly accelerated cognitive decline and found that carriers of the ACE rs1800764_C allele were more likely to show cognitive decline than noncarriers, particularly in those without college education. However, these effects do not survive after multiple testing corrections, and together they only explain 1.7% of the phenotypic variance in cognitive score change. This study suggests that AD risk variants and/or genes are not powerful predictors of cognitive decline in our Chinese sample.