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Introduction Ageing process is influenced by multi-dimensional factors collectively. Previous studies examined association of one separate factor with mortality without considering different manifestations of ageing process. We investigated associations of multi-dimensional factors with Accelerating Age (AA), a proxy to quantify ageing, in older Chinese. Methods 9,831 participants from Guangzhou Biobank Cohort Study were included. Four exposure domains of 15 variables including demographic and socioeconomic factors, lifestyle factors, stress across the life course and common diseases were assessed. AA was calculated based on chronological age and eight biomarkers. Traditional multivariable linear and Bayesian Network (BN) models were used. Results In both traditional and BN models, male sex, smoking, alcohol use, physical inactivity, greater waist circumference and body mass index (BMI) were associated with higher AA, with the adjusted β (95% confidence intervals (CI)) being 2.75 (2.40 to 3.09), 1.31 (0.87 to 1.76), 1.35 (0.55 to 2.15), 0.64 (0.40 to 0.88), 0.09 (0.06 to 0.11) and 0.13 (0.07 to 0.19) years, respectively. A Healthy Lifestyle Index (HLI) was constructed including the above lifestyle factors (non-smoking, non-alcohol use, physically active, non-central and non-general obesity) with a point assigned for each. A higher index indicates healthier lifestyle. Compared with participants with an HLI of 5, those with an HLI of 0-2 had 2.90 (2.48 to 3.32) years older AA. Conclusions Male sex, smoking, alcohol use, physical inactivity, greater waist circumference and BMI were associated with higher AA by 0.09 to 2.75 years, suggesting that adopting a healthy lifestyle may alleviate process of phenotypic ageing.

The aim of this paper is to develop 10-year cardiovascular disease (CVD) risk prediction models for the contemporary Chinese populations based on the Guangzhou Biobank Cohort Study (GBCS) and to compare its performance with models based on Framingham’s general cardiovascular risk profile and the Prediction for Atherosclerotic CVD Risk in China (China-PAR) project. Subjects were randomly classified into the training (n = 15,000) and validation (n = 12,721) sets. During an average of 12.0 years’ follow-up, 3,732 CVD events occurred. A 10-year sex-specific CVD risk prediction model including age, systolic blood pressure, use of antihypertensive medication, smoking, and diabetes was developed. Compared with the Framingham and China-PAR models, the GBCS model had a better discrimination in both women (c-statistic 0.72, 95% CI 0.71–0.73) and men (c-statistic 0.68, 95% CI 0.67–0.70), and the risk predicted was closer to the actual risk. This prediction model would be useful for identifying individuals at higher risks of CVD in contemporary Chinese populations.

Most studies on the associations of blood pressure (BP) with cardiovascular disease (CVD) risk were based on single or average BP levels. Knowledge on the association between BP trajectories and CVD in middle-aged individuals who are not on antihypertensive medication may inform the care of individuals in this group whose BPs are not controlled.Eight thousand nine hundred and sixty-nine participants aged 50-70 years, without CVD at baseline and not taking antihypertensive medication throughout the study, were included. Four time-points data from the Guangzhou Biobank Cohort Study were used to identify BP trajectories using latent class mixed model. Cox regression was used to investigate the association of BP trajectories with fatal and nonfatal CVD till April 2021.Three SBP trajectories were identified: 'low-slow-increase' characterized by SBP from 110 to 125 mmHg (86.5%); 'low-increase' from 110 to 150 mmHg (8.1%) and 'moderate-increase' from 125 to 155 mmHg (5.4%). Compared with the low-slow-increase group, the moderate-increase had the highest risk of CVD (hazard ratio = 1.76, 95% confidence interval = 1.34-2.29), ischemic heart disease (1.77, 1.01-3.09), myocardial infarction (3.52, 1.58-7.85), all strokes (1.88, 1.37-2.60), ischemic stroke (1.65, 1.10-2.49), haemorrhagic stroke (3.98, 1.30-12.12) and CVD mortality (2.41, 1.55-3.76). Higher risks of CVD (1.27, 1.01-1.61) and ischemic stroke (1.49, 1.07-2.09) in the low-increase group were also found.Most people between 50 and 70 years of age and not taking antihypertensive medication maintained a slow increase SBP trajectory over a follow-up period of approximately 7 years. However, those whose SBPs increased from low and moderate levels were associated with higher CVD risks.

Whether fish consumption is associated with all-cause, cardiovascular (CVD), ischemic heart disease (IHD) and stroke mortality remains inconclusive. We examined the association of fish consumption with all-cause, cardiovascular (CVD), ischemic heart disease (IHD) and stroke mortality in older men and women in south China. A total of 18,215 participants including men and women without CVD at baseline (2003–2006) from Guangzhou Biobank Cohort Study (GBCS) were included and followed up till December 2017. Deaths were identified through record linkage with the Death Registry. Information on fish consumption was obtained using a food frequency questionnaire. During an average follow-up of 11.4 (standard deviation = 2.1) years, 2,697 deaths occurred, including 917 total CVD, 397 IHD and 374 stroke deaths. After adjusting for potential confounders, compared with fish consumption of 0–3 servings/week (i.e., 0–21 g/day, one serving = 50 g), consumption of 4–6 servings/week (29–43 g/day) showed significantly lower risks of all-cause and CVD mortality (hazards ratio (HR) and 95% confidence interval (CI): 0.85 (0.76, 0.95) and 0.77 (0.64, 0.93), respectively), but the reduced risk of IHD mortality (HR (95% CI): 0.80 (0.60, 1.07)) was not significant. Consumption of 7–10 servings/week or higher showed no association with all-cause, CVD, IHD, and stroke mortality. Moderate fish consumption of 4–6 servings/week (29–43 g/day) was associated with lower all-cause and CVD mortality risk. Our findings support the current general advice on regular fish consumption also in middle-aged and older adults.

Association has been found between chronotype and cognitive function in conventional observational studies but whether this association is causal and if so, its direction, is uncertain. There are also concerns among people with later chronotype that their habits may be detrimental to cognitive function.We analyzed the association between chronotype (measured as sleep midpoint) and cognitive function (measured by Mini-Mental Status Examination (MMSE) and Delayed Word Recall Test (DWRT)) using multivariable linear regression on 14,582 participants in the Guangzhou biobank cohort study (GBCS) from 2008 to 2012. Using bidirectional Mendelian randomization, we used 207 single nucleotide polymorphisms (SNPs) associated with chronotype from the combination of UK Biobank and 23andMe (n = 697,828), and 127 SNPs associated with cognitive function from the combination of UK Biobank and COGENT consortium (n = 257,841).Observationally in GBCS, later chronotype was associated with better cognitive function (MMSE scores: β = 0.14 per hour; 95% confidence interval (CI), 0.09-0.19; DWRT scores: β = 0.07 per hour; 95% CI, 0.04-0.11). Bidirectional MR showed genetic predisposition to early, versus later, chronotype was not associated with cognitive function using inverse-variance weighted (β = -0.02; 95% CI, -0.05 to 0.01). However, better cognitive function was associated with decreased odds of early chronotype (UK Biobank: odds ratio = 0.88 per standardized score; 95% CI, 0.83-0.93; 23andMe: 0.87 per standardized score; 95% CI, 0.80-0.95).It is a reassuring finding for adults with later chronotype who may be concerned if such a habit has a negative impact on cognitive function.The National Natural Science Foundation of China; Natural Science Foundation of Guangdong; The University of Hong Kong Foundation for Educational Development and Research; The Health Medical Research Fund in Hong Kong; The University of Birmingham, UK.

We examined the association between whole grain and refined grain intake with all-cause, cancer and cardiovascular disease (CVD) mortality using the data from the Guangzhou Biobank Cohort Study.19,597 participants aged 50+ years were recruited from 2003 to 2006 and followed-up until April 2021. Multivariable Cox regression was used to calculate hazard radios (HRs) and 95% confidence intervals (CIs). Substitution analysis was used to replace a serving (50 g/day) of whole grain with a serving of refined grain.During 286,821 person-years of follow-up, 4385 deaths occurred, including 1450 from cancer, 1678 from CVD and 1257 from other causes. Compared with never whole grain intake, the highest intake category of whole grain ( 300 g/week) was associated with lower risk of all-cause (HR 0.90, 95% CI 0.82-0.98) and CVD mortality (HR 0.85, 0.74-0.98). Compared with the low-intake category of refined grain ( 500 g/day), the highest intake category ( 900 g/week) was associated with a lower risk of cancer mortality (HR 0.76, 0.62-0.95), but a higher risk of CVD mortality (HR 1.25, 1.03-1.51). No significant associations were found between whole grain intake and cancer mortality nor refined grain and all-cause mortality. The HRs of all-cause, cancer and CVD mortality substituting a serving of whole grain for refined grain were 0.96 (0.94-0.99), 1.01 (0.99-1.02) and 0.95 (0.90-0.99), respectively.We have first shown that in older Chinese, whole grain intake was associated with lower risk of all-cause and CVD mortality. Our results suggest that intake of whole grain of at least 300 g/week and refined grain of ≤ 900 g/day might be suitable for older Asian. Substituting 50 g/day of whole grain for refined grain was associated with a 4-5% lower risk of all-cause and CVD mortality.

Background To examine associations of baseline alcohol drinking with incident type 2 diabetes or impaired fasting glucose, and explore whether the associations were modified by genetic polymorphisms of aldehyde dehydrogenase-2 (ALDH2) and alcohol dehydrogenase-1B (ADH1B).Methods Information of alcohol consumption was collected at baseline from 2003 to 2008. Incident type 2 diabetes was defined as fasting glucose ≥7.0 mmol/l or post-load glucose ≥11.1 mmol/l at follow-up examination (2008-2012), self-reported type 2 diabetes and/or initiation of hypoglycemia medication or insulin during follow-up. Impaired fasting glucose was defined as fasting glucose ≥5.6 mmol/l and Results Of 15,716 participants without diabetes and 11,232 participants without diabetes and impaired fasting glucose at baseline, 1,624 (10.33%) developed incident type 2 diabetes, and 1,004 (8.94%) developed incident impaired fasting glucose during average 4 years of follow-up. After adjusting for sex, age, education, occupation, personal annual income, smoking, physical activity, body mass index, waist/hip ratio, health status, family history of diabetes, compared with never drinking, occasional or moderate alcohol drinking was not associated with risk of incident type 2 diabetes+impaired fasting glucose (odds ratio (OR) 1.08, 95% confidence interval (CI) 0.94-1.25, and 0.89 (0.68-1.16), respectively), but heavy alcohol drinking was associated with a higher risk of incident type 2 diabetes+impaired fasting glucose (1.83, 1.25-2.69). No interactions of sex, overweight/obesity and genetic polymorphisms of ADH1B or ALDH2 genes with alcohol drinking on incident type 2 diabetes and/or impaired fasting glucose were found (p for interaction from 0.12 to 0.81). Conclusions Our results support a detrimental effect of heavy alcohol use on impaired fasting glucose and type 2 diabetes. No protective effect was found for those carrying lower risk alleles for ADH1B and ALDH2 genes.

Background The role of smoking in nasopharyngeal carcinoma (NPC) remains uncertain, especially in endemic regions. We conducted an individual participant data (IPD) meta-analysis of prospective cohort studies to investigate the associations between smoking exposure and risk of NPC. Methods We obtained individual participant data of 334 935 male participants from six eligible population-based cohorts in NPC-endemic regions, including two each in Guangzhou and Taiwan, and one each in Hong Kong and Singapore. We used one- and two-stage approaches IPD meta-analysis and Cox proportional hazard models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) of NPC for smoking exposure adjusting for age and drinking status. Results During 2 961 315 person-years of follow-up, 399 NPC evens were ascertained. Risks of NPC were higher in ever versus never smokers (HRone-stage = 1.32, 95% CI = 1.07-1.63, P = 0.0088; HRtwo-stage = 1.27, 1.01-1.60, 0.04). These positive associations appeared to be stronger in ever smokers who consumed 16+ cigarettes/day (HRone-stage = 1.67, 95% CI = 1.29-2.16, P = 0.0001), and in those who started smoking at age younger than 16 (2.16, 1.33-3.50, 0.0103), with dose-response relationships (P-values for trend = 0.0028 and 0.0103, respectively). Quitting (versus daily smoking) showed a small reduced risk (stopped for 5+ years: HRone-stage = 0.91, 95% CI = 0.60-1.39, P = 0.66; for former smokers: HRtwo-stage = 0.84, 0.61-1.14, 0.26). Conclusions This first IPD meta-analysis from six prospective cohorts in endemic regions has provided robust observational evidence that smoking increased NPC risk in men. NPC should be added to the 12–16 cancer sites known to be tobacco-related cancers. Strong tobacco control policies, preventing young individuals from smoking, would reduce NPC risk in endemic regions.

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.

Mendelian randomization (MR) analyses from the West provide evidence that obesity causes lower 25-hydroxyvitamin D [25(OH)D]. As Asian populations are prone to metabolic disorders at a lower body mass index (BMI), whether the association remains in Asian is unclear. We studied whether obesity causes vitamin D deficiency using MR analysis in Chinese.We used data from the Guangzhou Biobank Cohort Study. A genetic score including seven BMI-related single-nucleotide polymorphisms (n = 15,249) was used as the instrumental variable (IV) for BMI. Two-stage least square regression and conventional multivariable linear regression in 2,036 participants with vitamin D data were used to analyze association of BMI with vitamin D.Proportion of variation explained by the genetic score was 0.7% and the first stage F-statistic for MR analysis was 103. MR analyses showed that each 1 kg/mWe have first shown by MR and conventional multivariable linear regression that higher BMI causes vitamin D deficiency in Chinese. Our findings highlight the importance of weight control and suggest that vitamin D supplementation may be needed in individuals with overweight or obesity.

The long-term effects of a low-carbohydrate diet (LCD) on mortality, accounting for the quality and source of the carbohydrate, are unclear. Hence, we examined the associations of LCDs with all-cause and cause-specific mortality in a prospective cohort study. A total of 20,206 participants (13.8% diabetes) aged 50+ years were included. Overall, vegetable-based and meat-based LCD scores were calculated based on the percentage of energy as total and subtypes of carbohydrates, fat, and protein. Cox regression analysis was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). During 294,848 person-years of follow-up, 4624 deaths occurred, including 3661 and 963 deaths in participants without and with diabetes, respectively. In all participants, overall LCD score was not associated with all-cause and cause-specific mortality, after multivariable adjustment. However, for the highest versus the lowest quartiles of vegetable-based LCD, the adjusted HRs (95%CIs) of all-cause and CVD mortality were 1.16 (1.05–1.27) and 1.39 (1.19–1.62), respectively. The corresponding values for highest versus lowest quartiles of meat-based LCD for all-cause and CVD mortality were 0.89 (0.81–0.97) and 0.81 (0.70–0.93), respectively. Similar associations were found in participants without diabetes. In patients with diabetes, the adjusted HR (95%CI) of CVD mortality for the highest versus the lowest quartiles of vegetable-based LCD was 1.54 (1.11–2.14). Although there were no significant associations with overall LCD score, we found that the vegetable-based LCD score was positively, whereas the meat-based LCD score was negatively, associated with all-cause and CVD mortality in older Asian people.

Background: Studies on long-term effects of low-carbohydrate diet (LCD) on mortality accounting for quality and sources of carbohydrate are unclear. Hence, we examined the associations of LCDs with all-cause and cause-specific mortality in a population-based cohort study.Methods: Prospective study using data from Guangzhou Biobank Cohort Study (GBCS). 20,206 participants (13.8% diabetes) aged 50+ years were recruited from 2003-2006 and followed up until 19 April 2021.Overall, vegetable-based, and meat-based LCD scores were calculated based on the percentage of energy as total and subtypes of carbohydrate, fat and protein. The main outcomes were all-cause, cancer and CVD mortality. Cox regression were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).Results: During 294,848 person-years of follow-up, 4,624 deaths occurred, including 3,661 and 963 deaths in participants without and with diabetes, respectively. In all participants, overall LCD score was not associated with all-cause and cause-specific mortality after multivariable adjustment. However, the adjusted HRs (95%CIs) of all-cause and CVD mortality for the highest, versus the lowest, quartiles of vegetable-based were 1.16 (1.05-1.27 PtrendPtrendPtrend=0.007) and 0.81 (0.70-0.93 Ptrend=0.02), respectively. Similar associations were found in participants after excluding those with diabetes. In diabetic patients, there was no association between vegetable-based LCD or meat-based LCD scores and mortality. However, we found a positive association between the highest quartile of vegetable-based LCD score and CVD mortality comparing with the lowest quartile (HR 1.54, 95% CI, 1.11-2.14 Ptrend=0.003).Conclusions: Vegetable-based LCD score was positively and meat-based LCD score was negatively associated with all-cause and CVD mortality. Inconsistencies in the literature on the health effect of LCD may reflect the importance of the geographical context and age-related nutrient composition of the diet.

Context China has the largest number of people with type 2 diabetes mellitus (T2DM) in the world. Data from previous studies have suggested that up to one-fifth of individuals with diabetes would be missed without an oral glucose tolerance test (OGTT). To date, there is little information on the mortality risk of these individuals. Objective We estimated the association of different indicators of hyperglycemia with mortality in the general Chinese population. Design Prospective cohort study. Setting China. Participants A total of 17 939 participants aged 50+ years. Exposures Previously diagnosed diabetes and newly detected diabetes defined by fasting glucose (≥7.0 mmol/L), 2-hour postload glucose (≥11.1 mmol/L), or hemoglobin A1c (HbA1c, ≥6.5%). Main Outcomes Measures Deaths from all-cause, cardiovascular disease, and cancer were identified by record linkage with death registration. Results During 7.8 (SD, 1.5) years’ follow-up, 1439 deaths were recorded. Of 3706 participants with T2DM, 2126 (57%) had known T2DM, 118 (3%) were identified by isolated elevated fasting glucose, 1022 (28%) had isolated elevated postload glucose, and 440 (12%) had both elevated fasting and postload glucose. Compared with normoglycemia, the hazard ratio (95% confidence interval) of all-cause mortality was 1.71 (1.46-2.00), 0.96 (0.47-1.93), 1.43 (1.15-1.78), and 1.82 (1.35-2.45) for the 4 groups, respectively. T2DM defined by elevated HbA1c was not significantly associated with all-cause mortality (hazard ratio, 1.17; 95% confidence interval, 0.81-1.69). Conclusion Individuals with isolated higher 2-h postload glucose had a higher risk of mortality by 43% than those with normoglycemia. Underuse of OGTT leads to substantial underdetection of individuals with a higher mortality risk and lost opportunities for early intervention.

Background Although social isolation has been associated with a higher mortality risk, little is known about the potential different impacts of face-to-face and non-face-to-face isolation on mortality. We examined the prospective associations of four types of social isolation, including face-to-face isolation with co-inhabitants and non-co-inhabitants, non-face-to-face isolation, and club/organization isolation, with all-cause and cause-specific mortality separately. Methods This prospective cohort study included 30,430 adults in Guangzhou Biobank Cohort Study (GBCS), who were recruited during 2003–2008 and followed up till Dec 2019. Results During an average of 13.2 years of follow-up, 4933 deaths occurred during 396,466 person-years. Participants who lived alone had higher risks of all-cause (adjusted hazard ratio (AHR) 1.24; 95% confidence interval (CI) 1.04-1.49) and cardiovascular disease (CVD) (1.61; 1.20–2.03) mortality than those who had ≥ 3 co-habitant contact after adjustment for thirteen potential confounders. Compared with those who had ≥ 1 time/month non-co-inhabitant contact, those without such contact had higher risks of all-cause (1.60; 1.20–2.00) and CVD (1.91; 1.20–2.62) mortality. The corresponding AHR (95% CI) in participants without telephone/mail contact were 1.27 (1.14–1.42) for all-cause, 1.30 (1.08–1.56) for CVD, and 1.37 (1.12–1.67) for other-cause mortality. However, no association of club/organization contact with the above mortality and no association of all four types of isolation with cancer mortality were found. Conclusions In this cohort study, face-to-face and non-face-to-face isolation were both positively associated with all-cause, CVD-, and other-cause (but not cancer) mortality. Our finding suggests a need to promote non-face-to-face contact among middle-aged and older adults.

Background Chronic inflammatory diseases are linked to an increased risk of stroke events. The white blood cell (WBC) count is a common marker of the inflammatory response. However, it is unclear whether the WBC count, its subpopulations and their dynamic changes are related to the risk of fatal stroke in relatively healthy elderly population. Methods In total, 27,811 participants without a stroke history at baseline were included and followed up for a mean of 11.5 (standard deviation = 2.3) years. After review of available records, 503 stroke deaths (ischaemic 227, haemorrhagic 172 and unclassified 104) were recorded. Cox proportional hazards regression was used to assess the associations between the WBC count, its subpopulations and their dynamic changes (two-phase examination from baseline to the 1st follow-up) and the risk of fatal all stroke, fatal ischaemic stroke and fatal haemorrhagic stroke. Results (i) Regarding the WBC count in relation to the risk of fatal stroke, restricted cubic splines showed an atypically U-curved association between the WBC count and the risk of fatal all stroke occurrence. Compared with those in the lowest WBC count quartile ( 7.2*10^9/L) had a 53 and 67% increased risk for fatal all stroke (adjusted hazard ratio [aHR] = 1.53, 95% confidence interval (CI) 1.16–2.02, P = 0.003) and fatal haemorrhagic stroke (aHR = 1.67, 95% CI 1.10–2.67, P = 0.03), respectively; compared with those in the lowest quartile ( 4.5*10^9/L) had a 45 and 65% increased risk for fatal all stroke (aHR = 1.45, 95% CI 1.10–1.89, P = 0.008) and fatal ischaemic stroke (aHR = 1.65, 95%CI 1.10–2.47 P = 0.02), respectively. With the additional adjustment for C-reactive protein, the same results as those for all stroke and ischaemic stroke, but not haemorrhagic stroke, were obtained for the WBC count (4 ~ 10*10^9/L) and the NEUT count (the NEUT counts in the top 1% and bottom 1% at baseline were excluded). (ii) Regarding dynamic changes in the WBC count in relation to the risk of fatal stroke, compared with the stable group (− 25% ~ 25%, dynamic changes from two phases of examination (baseline, from September 1st, 2003 to February 28th, 2008; 1st follow-up, from March 31st 2008 to December 31st 2012)), the groups with a 25% increase in the WBC count and NEUT count respectively had a 60% (aHR = 1.60, 95% CI 1.07–2.40, P = 0.02) and 45% (aHR = 1.45, 95% CI1.02–2.05, P = 0.04) increased risk of fatal all stroke occurrence. Conclusions The WBC count, especially the NEUT count, was associated with an increased risk of fatal all stroke occurrence. Longitudinal changes in the WBC count and NEUT count increase in excess of 25% were also associated with an increased risk of fatal all stroke occurrence in the elderly population.

To our knowledge, evidence regarding the association of a low-carbohydrate diet (LCD) with the risk for stroke is limited. The aim of this study was to examine the association between an LCD and stroke in a population with relatively high-carbohydrate intake and risk for stroke and use a meta-analysis to update the evidence.The study included 19 850 participants aged ≥50 y without stroke history at baseline in the Guangzhou Biobank Cohort Study. LCD score was calculated based on the percentage of energy from carbohydrate, protein, and fat (range 0-30 points), with a higher score indicating a lower intake of carbohydrate and a higher intake of fat and protein.During an average follow-up of 13.1 y, 1661 stroke events and deaths occurred, including 1255 ischemic strokes. The second, versus the lowest quartile of animal-based LCD scores, were associated with lower risks for all stoke and ischemic stroke (hazards ratio [HR], 0.87; 95% confidence interval [CI], 0.77-0.997, and HR, 0.83; 95% CI, 0.72-0.97). Non-significant associations of plant-based or total LCD scores with the risk for stoke were found.In a population consuming high levels of carbohydrates and low levels of protein and fat, a moderate level of animal-based LCD, but not plant-based LCD, was associated with a lower risk for stroke.

Previous studies showed that some components in tea had potential beneficial effects on depression. However, population-based studies examining the potential benefits of tea on depression are limited. We hypothesized that older Chinese with habitual tea consumption had lower levels of depressive symptoms than those without habitual tea consumption. A cross-sectional analysis of baseline data from the Guangzhou Biobank Cohort Study was conducted. Depressive symptoms were measured by the 15-item Geriatric Depression Scale (GDS) score (continuous), with the presence defined by a GDS ≥ 8. Of 10,014 participants, 421 (4.20%) had depressive symptoms. After adjusting for potential confounders, compared with never-consumers, occasional and regular consumers had lower GDS scores (β [95% confidence interval]: -0.29 [-0.46, -0.11] and -0.60 [-0.78, -0.42], respectively), and regular consumers showed lower odds of depressive symptoms (odds ratio [95% CI]: 0.51 (0.35-0.72). In regular tea consumers, greater frequency, amount per occasion and per week, and higher amount-years showed lower GDS score (all P for trend0.001) and lower odds of depressive symptoms (all P for trend.05) than nonconsumers. The results were similar by different types of tea (green tea, black tea, and oolong tea) consumed. Further adjustment for social characteristics of tea consumption attenuated the association slightly but not fully. In conclusion, habitual tea consumption was associated with lower levels of depressive symptoms among older Chinese, which might be partly explained by social interaction during consumption. Further investigation on causation and mechanisms, including mechanistic randomized controlled trials is warranted.

Objective: From genome-wide association studies, brain-derived neurotrophic factor (BDNF) locus on chromosome 11 was the only SNP associated with both smoking and body mass index (BMI). This study aims to explore the unique genetic predisposition to obesity in former smokers by examining the effects of BDNF on BMI and waist circumference (WC). Methods: We included 15,072 ethnic Chinese participants in the Guangzhou Biobank Cohort Study (GBCS) with data of four BDNF SNPs related to both body mass index (BMI) and smoking behavior. We used baseline smoke exposure data in 2003-2007 and follow-up outcomes of general obesity (by BMI) and central obesity (waist circumference) in 2008-2012. Odds ratios (ORs) and 95% confidence intervals (CIs) for general obesity and central obesity associated with these SNPs were derived from logistic regression. Results: Of 15,072 participants (3,169 men and 11,903 women), 1,664 (11.0%) had general and 7,868 (52.2%) had central obesity. We replicated the associations of the four BDNF SNPs with obesity and smoking status in the GBCS. In 1,233 former smokers, the rs6265 GG, versus AA, genotype was associated with higher risks of general obesity (OR=1.79, 95% CI=1.06-3.01) and central obesity (OR=2.08, 95% CI=1.47-2.92) after adjustment. These associations were not significant in never or current smokers. In former heavy (≥20 cigarettes/day) smokers, the rs6265 GG genotype showed a higher odds for general obesity (OR=2.15, 95% CI=1.05-4.40), while no association was found in former light (1-9 cigarettes/day) smokers. Similar results were found for the association of rs6265 with central obesity and for the associations of other two BDNF SNPs (rs4923457 and rs11030104) with both general and central obesity. Conclusions: We firstly identified the genetic predisposition (BDNF SNPs) to general and central obesity in former smokers, particularly in former heavy smokers. Funding Statement: This study was supported by research grants from the Guangdong Natural Science Foundation of China, Guangdong, China (Grant number: 9451062001003477); the Guangzhou Science and Information Bureau, Guangzhou, China (2012J5100041); the National Natural Science Foundation of China (81773502 and 81703308). The study is funded by The University of Hong Kong Foundation for Educational Development and Research, Hong Kong; the Guangzhou Public Health Bureau and the Guangzhou Science and Technology Bureau, Guangzhou, China; and The University of Birmingham, UK. Declaration of Interests: None declared. Ethics Approval Statement: The GBCS was approved by the Medical Ethics Committee of the Guangzhou Medical Association. All participants provided written informed consent before participating.

OBJECTIVE To examine the associations of natural menopausal age with cardiovascular disease risk factors and whether the associations varied by parity in older Chinese women. METHODS Information of demographic characteristics, lifestyles, and reproductive factors was collected by face-to-face interview. Framingham Risk Score was used as an indicator of cardiovascular disease risk, with a score ≥ 10% considered as high cardiovascular disease risk (vs low, dichotomous). Multivariable logistic and linear regressions were used to examine the associations of menopausal age with cardiovascular disease risk factors. RESULTS Of 18,339 women aged 50+ years, the average (standard deviation) age was 61.8 (6.9) years. Compared with women with menopausal age of 45 to 54 years, after adjustment for multiple potential confounders, women with menopausal age

The aim of this paper is to develop 10-year cardiovascular disease (CVD) risk prediction models for the contemporary Chinese populations based on the Guangzhou Biobank Cohort Study (GBCS) and to compare its performance with models based on Framingham's general cardiovascular risk profile and the Prediction for Atherosclerotic CVD Risk in China (China-PAR) project. Subjects were randomly classified into the training (n = 15,000) and validation (n = 12,721) sets. During an average of 12.0 years' follow-up, 3,732 CVD events occurred. A 10-year sex-specific CVD risk prediction model including age, systolic blood pressure, use of antihypertensive medication, smoking, and diabetes was developed. Compared with the Framingham and China-PAR models, the GBCS model had a better discrimination in both women (c-statistic 0.72, 95% CI 0.71-0.73) and men (c-statistic 0.68, 95% CI 0.67-0.70), and the risk predicted was closer to the actual risk. This prediction model would be useful for identifying individuals at higher risks of CVD in contemporary Chinese populations.

Background: Lower hand grip strength has been linked to cognitive impairment, but studies in older Chinese are limited. We examined the association of hand grip strength with cognitive function in a large sample of older Chinese. Methods: 6806 participants aged 50+ years from the Guangzhou Biobank Cohort Study (GBCS) were included. Relative grip strength was calculated by absolute handgrip strength divided by the body mass index (BMI). Cognitive function was assessed using the Delayed Word Recall Test (DWRT, from 0 to 10) and the Mini Mental State Examination (MMSE, from 0 to 30), with higher scores indicating better cognition. Results: After adjusting for multiple potential confounders, lower absolute grip strength and relative grip strength were significantly associated with lower DWRT (all p < 0.05) in all participants. No significant interaction effects between sex and handgrip strength on cognitive impairment were found (p from 0.27 to 0.87). No significant association between handgrip strength and total MMSE scores was found in the total sample or by sex (p from 0.06 to 0.50). Regarding the individual components of MMSE, lower absolute and relative grip strength were significantly associated with lower scores of the recall memory performance in all participants (p from 0.003 to 0.04). Conclusion: We have shown for the first time a positive association of grip strength with recall memory performance, but not general cognitive function in older people, which warrants further investigation.

Background Several studies have shown positive associations between higher WBC count and deaths from all-causes, CHD, stroke and cancer among occidental populations or developed countries of Asia. No study on the association of WBC count with all-cause and cause-specific mortality in Chinese populations was reported. We studied this using prospective data from a large Chinese cohort. Methods We used prospective data from the Guangzhou Biobank Cohort Study (GBCS), a total of 29,925 participants in present study. A Cox proportional hazards regression model was used to estimate the hazard ratios (HR) and 95% confidence interval (CI). Results The hazard ratios (HR) for all-cause, CHD, and respiratory disease mortality for the highest decile of WBC count (women > 8.2 × 109/L; men > 8.8 × 109/L) was 1.83 (95% confidence interval (CI) 1.54, 2.17), 3.02 (95% CI 1.84, 4.98) and 2.52 (95% CI 1.49, 4.27), respectively, after adjusting for multiple potential confounders. The associations were similar when deaths during the first 2 years of follow-up were excluded. After further adjusting for pulmonary function, the highest decile of WBC count was associated with 90% higher risk of respiratory disease mortality (HR 1.90, 95% CI 1.08, 3.33). No evidence for an association between higher WBC count and cancer mortality was found. Sub-type analysis showed that only granulocyte count remained significantly predictive of all-cause, CHD, and respiratory disease mortality. Conclusions Elevated WBC, specifically granulocyte, count was associated with all-cause, CHD and respiratory mortality in southern Chinese. Further investigation is warranted to clarify whether decreasing inflammation would attenuate WBC count associated mortality. Electronic supplementary material The online version of this article (10.1186/s12889-018-6073-6) contains supplementary material, which is available to authorized users.

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.

ObjectiveTo examine the associations of change in body mass index (BMI) and waist circumference (WC) over an average of 4 years with subsequent mortality risk in middle-aged to older Chinese.DesignProspective cohort study based on the Guangzhou Biobank Cohort Study.SettingCommunity-based sample.Participants17 773 participants (12 956 women and 4817 men) aged 50+ years.Primary and secondary outcome measuresPrimary outcome measure was all-cause mortality. Secondary outcome measures were cardiovascular disease (CVD) and cancer mortality. Causes of death were obtained via record linkage, and coded according to the International Classification of Diseases (tenth revision).Results1424 deaths (53.4% women) occurred in the 17 773 participants (mean age 61.2, SD 6.8 years) during an average follow-up of 7.8 (SD=1.5) years, and 97.7% of participants did not have an intention of weight loss . Compared with participants with stable BMI, participants with BMI loss (>5%), but not gain, had a higher risk of all-cause mortality (HR=1.49, 95% CI 1.31 to 1.71), which was greatest in those who were underweight (HR=2.45, 95% CI 1.31 to 4.59). Similar patterns were found for WC. In contrast, for participants with a BMI of ≥27.5 kg/m2, BMI gain, versus stable BMI, was associated with 89% higher risk of all-cause mortality (HR=1.89, 95% CI 1.25 to 2.88), 72% higher risk of CVD mortality (HR=1.72, 95% CI 0.80 to 3.72) and 2.27-fold risk of cancer mortality (HR=2.27, 95% CI 1.26 to 4.10).ConclusionIn older people, unintentional BMI/WC loss, especially in those who were underweight was associated with higher mortality risk. However, BMI gain in those with obesity showed excess risks of all-cause and cancer mortality, but not CVD mortality. Frequent monitoring of changes in body size can be used as an early warning for timely clinical investigations and interventions and is important to inform appropriate health management in older Chinese.

Background There is a link between hyperglycemia and mechanical functions of muscle. However, existing evidence of the association between hyperglycemia and weaker muscle strength is limited and inconsistent. We examined whether glycemic status was associated with relative grip strength (RGS) in older Chinese. Methods In 2008–2012, 9180 participants (2516 men and 6664 women) from the Guangzhou Biobank Cohort Study had fasting and 2-h post-load glucose measured. Glycemic status was categorized as normoglycaemia, prediabetes (i.e., impaired fasting glucose and/or impaired glucose tolerance) and diabetes. RGS was assessed using a Jamar Hydraulic Hand Dynamometer divided by body mass index. General linear model was used to assess the association of glycemic status with RGS. Results After adjusting for age, smoking status, alcohol use, physical activity, health status, body fat percentage and waist circumference, in men, hyperglycemia was associated with a lower RGS, with the RGS being 1.38 (95% confidence interval (CI) = 1.34, 1.42) in normoglycaemia, 1.35 (95% CI = 1.30, 1.39) in prediabetes, 1.33 (95% CI = 1.29, 1.38) in newly diagnosed diabetes and 1.32 (95% CI = 1.27, 1.37) in known diabetes (P for trend P values from 0.002 to 0.03). Conclusions Higher fasting glucose was associated with reduced grip strength in a dose-response manner, and the association was significant even in women with normoglycaemia. Our findings suggest that lowering glucose across the whole range might be important in preserving muscle strength, especially in aging women.