Objective To comprehensively examine the potential impacts of prenatal experience of the Chinese Great Famine on chronic disease risks in the middle age. Methods This study included 92 284 participants aged 39–51 years from China Kadoorie Biobank born around the famine period and without major chronic diseases at baseline. We categorised participants into non-famine births (born between 1 October 1956 and 30 September 1958, and 1 October 1962 and 30 September 1964) and famine births (born between 1 October 1959 and 30 September 1961). The outcomes were incident cardiovascular disease, cancer and respiratory system disease. Cox regression was used to estimate adjusted HR and 95% CI for famine exposure. Subgroup analyses were performed according to baseline characteristics. Results During a median 10.1 years of follow-up, we identified 4626 incident ischaemic heart disease (IHD) cases, 7332 cerebrovascular disease cases, 3111 cancer cases and 16 081 respiratory system disease cases. In the whole population, prenatal famine exposure was not statistically associated with the risks of developing any chronic diseases in adulthood. However, for urban participants, compared with non-famine births, famine births had a higher risk of cerebrovascular disease (HR 1.18; 95% CI 1.09 to 1.28); such association was not shown for rural participants (p for interaction <0.001). Also, we observed the associations of prenatal famine exposure with IHD (HR 1.15; 95% CI 1.05 to 1.26) and cerebrovascular disease (HR 1.13; 95% CI 1.05 to 1.21) in participants with lower physical activity level, but not in those with higher ones (all p for interaction=0.003). Conclusion Our findings indicate that prenatal exposure to the Chinese famine might be associated with an increased cardiovascular risk and such risk may be modified by adult lifestyle.

Background Lean body mass has been identified as a key determinant of left ventricular mass and wall thickness. However, the importance of lean body mass or other body‐size measures as normative determinants of carotid intima‐media thickness (cIMT), a widely used early indicator of atherosclerosis, has not been well established. Methods and Results Carotid artery ultrasound measurements of cIMT and carotid artery plaque burden (derived from plaque number and maximum size) and measurements of body size, including height, body mass index, weight, body fat proportion, and lean body mass ([1−body fat proportion]×weight), were recorded in 25 020 participants from 10 regions of China. Analyses were restricted to a healthy younger subset (n=6617) defined as never or long‐term ex‐regular smokers aged <60 years (mean age, 50) without previous ischemic heart disease, stroke, diabetes mellitus, or hypertension and with plasma non‐high‐density lipoprotein cholesterol <4 mmol/L. Among these 6617 participants, 86% were women (because most men smoked) and 9% had carotid artery plaque. In both women and men separately, lean body mass was strongly positively associated with cIMT, but was not associated with plaque burden: overall, each 10 kg higher lean body mass was associated with a 0.03 (95% CI, 0.03–0.04) mm higher cIMT (P=5×10−33). Fat mass, height, and other body‐size measures were more weakly associated with cIMT. Conclusions The strong association of lean body mass with cIMT, but not with plaque burden, in healthy adults suggests a normative relationship rather than reflecting atherosclerotic pathology. Common mechanisms may underlie the associations of lean body mass with cIMT and with nonatherosclerotic vascular traits.

Background Active commuting is related to a higher level of physical activity but more exposure to ambient air pollutants. With the rather serious air pollution in urban China, we aimed to examine the association between active commuting and risk of incident cardiovascular disease in the Chinese population. Methods and Results A total of 104 170 urban commuters without major chronic diseases at baseline were included from China Kadoorie Biobank. Self‐reported commuting mode was defined as nonactive commuting, work at home or near home, walking, and cycling. Multivariable Cox regression was used to examine associations between commuting mode and cardiovascular disease. Overall, 47.2% of the participants reported nonactive commuting, 13.4% reported work at home or work near home, 20.1% reported walking, and 19.4% reported cycling. During a median follow‐up of 10 years, we identified 5374 incidents of ischemic heart disease, 664 events of hemorrhagic stroke, and 4834 events of ischemic stroke. After adjusting for sex, socioeconomic status, lifestyle factors, sedentary time, body mass index, comorbidities, household air pollution, passive smoking, and other domain physical activity, walking (hazard ratio, 0.90; 95% CI, 0.84–0.96) and cycling (hazard ratio, 0.81; 95% CI, 0.74–0.88) were associated with a lower risk of ischemic heart disease than nonactive commuting. Cycling was associated with a lower risk of ischemic stroke (hazard ratio, 0.92; 95% CI, 0.84–1.00). No significant association was found of walking or cycling with hemorrhagic stroke. The associations of commuting mode with major cardiovascular disease were consistent among men and women and across different levels of other domain physical activity. Conclusions In urban China, cycling was associated with a lower risk of ischemic heart disease and ischemic stroke. Walking was associated with a lower risk of ischemic heart disease.

Objective Aim to examine the independent and joint associations of physical activity (PA) and sedentary leisure-time (SLT) with risk of diabetes and assess the extent to which these associations were mediated by adiposity. Research design and methods The prospective China Kadoorie Biobank recruited ~512 000 adults from 10 diverse areas across China. Self-reported PA was estimated based on type, frequency and duration of specific types of PA, covering four domains (occupation, leisure, household and commuting). SLT was defined as hours per day spent watching television, reading or playing card games. Stratified Cox proportional hazards models were used to estimate adjusted HRs (aHRs) for PA and SLT associated with incident diabetes. Analyses were stratified by age-at-risk (5-year intervals), sex and region and adjusted for household income, education, alcohol consumption, smoking, fresh fruit intake, self-reported general health status, family history of diabetes and body mass index (BMI) status. Analyses of total PA, occupational and non-occupational PA and SLT were mutually adjusted for each other, as appropriate. Results After ~9 years of follow-up, there were 14 940 incident diabetes cases among 460 736 participants without prior diabetes or cardiovascular diseases at baseline. The mean (SD) age at baseline was 51 (10.6) years, 59% were women and 43% resided in urban areas. Overall, the mean BMI was 23.5 (3.3) kg/m 2 , which differed by ~0.5 kg/m 2 among individuals in the highest compared with the lowest PA and SLT groups. PA was inversely associated the risk of diabetes 16% (aHR: 0.84, 95% CI 0.81 to 0.88) lower in top than bottom fifth. After further adjustment for BMI this was attenuated to 0.99 (95% CI 0.98 to 1.00). SLT was positively associated with diabetes and each 1 hour per day higher usual level was associated with aHR of 1.13 (95% CI 1.09 to 1.17) for diabetes, attenuated to 1.05 (95% CI 1.01 to 1.09) after further adjustment for BMI. Conclusions Among Chinese adults, higher levels of PA and lower levels of SLT were associated with lower risks of diabetes with no evidence of effect modification by each other. These associations appeared to arise mainly through adiposity.

Key Points Question Is chronic hepatitis B virus infection associated with a higher risk of any cancer type when compared with individuals without hepatitis B virus? Findings This population-based cohort study of 496 732 Chinese individuals found that hepatitis B surface antigen seropositivity was associated with the risk of hepatocellular carcinoma, stomach cancer, colorectal cancer, oral cancer, pancreatic cancer, and lymphoma. The associations were validated in an independent population and tissue-based studies. Meaning Chronic hepatitis B virus infection was associated with nonliver cancer, especially digestive system cancers.

Abstract Background Simultaneously adhering to multiple healthy lifestyle factors has been related to up to 90% reduction in type 2 diabetes (T2DM) incidence in White populations; however, little is known about whether such protective effects persist in other non-White populations. Methods We examined the associations of six lifestyle factors with T2DM in the China Kadoorie Biobank of 461 211 participants aged 30–79 years without diabetes, cardiovascular diseases or cancer at baseline. We defined low-risk lifestyle factors as non-smoking or having stopped for reasons other than illness; alcohol consumption of <30 g/day; upper quarter of the physical activity level; diet rich in vegetables and fruits, low in red meat and with some degree of replacement of rice with wheat; body mass index (BMI) of 18.5–23.9 kg/m2; and waist-to-hip ratio (WHR) <0.90 (men)/<0.85 (women). Results During a median of 7.2 years of follow-up, we identified 8784 incident T2DM. In multivariable-adjusted analyses, two important risk factors for developing T2DM were higher BMI and WHR. Compared with participants without any low-risk factors, the hazard ratio [95% confidence interval (CI)] for those with at least three low-risk factors was 0.20 (0.19, 0.22). Approximately 72.6% (64.2%, 79.3%) of the incident diabetes were attributable to the combination of BMI, WHR, diet and physical activity. The population attributable risk percentage (PAR%) of diabetes appeared to be similar for men and women, and higher among urban, older and obese participants. Conclusions Our findings indicate that adherence to a healthy lifestyle may substantially lower the burden of T2DM in the Chinese population.

Importance:Diabetes is a known risk factor for cardiovascular disease (CVD). Substantial uncertainty remains, however, about the relevance to CVD risk for blood glucose levels below the diabetes threshold. Objective:To examine the association of random plasma glucose (RPG) levels with the risk for major CVD in Chinese adults without known diabetes. Design, Setting, and Participants:This prospective cohort study included 467 508 men and women aged 30 to 79 years with no history of diabetes, ischemic heart disease (IHD), stroke, or transient ischemic attack. Participants were recruited from 5 urban and 5 rural diverse locations across China from June 25, 2004, to July 15, 2008, and followed up to January 1, 2014. Exposures:Baseline and usual (longer-term average) RPG level. Main Outcomes and Measures:Cardiovascular deaths, major coronary events (MCE) (including fatal IHD and nonfatal myocardial infarction), ischemic stroke (IS), major occlusive vascular disease (MOVD) (including MCE or IS), and intracerebral hemorrhage. Preliminary validation of stroke and IHD events demonstrated positive predictive values of approximately 90% and 85%, respectively. Cox regression yielded adjusted hazard ratios (aHRs) for CVD associated with RPG levels. Results:Among the 467 508 participants (41.0% men; 59.0% women; mean [SD] age, 51 [11] years), a significant positive association of baseline RPG levels with CVD risks continued to 4.0 mmol/L (72 mg/dL). After adjusting for regression dilution bias, each 1-mmol/L (18-mg/dL) higher usual RPG level above 5.9 mmol/L (106 mg/dL) was associated with an 11% higher risk for cardiovascular death (6645 deaths; aHR, 1.11; 95% CI, 1.10-1.13). Similarly strong positive associations were seen for MCE (3270 events; aHR, 1.10; 95% CI, 1.08-1.13), IS (19 153 events; aHR, 1.08; 95% CI, 1.07-1.09), and MOVD (22 023 events; aHR, 1.08; 95% CI, 1.07-1.09). For intracerebral hemorrhage, the association was weaker, but also significant (4326 events; aHR, 1.05; 95% CI, 1.02-1.07). These associations persisted after excluding participants who developed diabetes during follow-up. Conclusions and Relevance:Among adult Chinese without diabetes, lower RPG levels are associated with lower risks for major CVDs, even within a normal range of blood glucose levels.