Associations of soy product intake with all-cause, cardiovascular disease and cancer mortality: Guangzhou Biobank Cohort Study and updated meta-analyses.

PURPOSE: We examined the associations of soy product intake with all-cause, cardiovascular disease (CVD), and cancer mortality and mediations through CVD risk factors based on the Guangzhou Biobank Cohort Study (GBCS), and conducted updated meta-analyses. METHODS: A total of 29,825 participants aged 50 + years were included. Causes of death were identified through record linkage. Soy product intake was assessed by food frequency questionnaire. Cox proportional hazards regression was used to analyze the associations between soy product intake and mortality, yielding hazard ratios (HRs) and 95% confidence intervals (CIs). Mediation analyses with CVD risk factors as mediators, and updated meta-analyses were conducted. RESULTS: During 454,689 person-years of follow-up, 6899 deaths occurred, including 2694 CVD and 2236 cancer. Participants who consumed soy product of 1-6 portions/week, versus no consumption, had significantly lower risks of all-cause and CVD mortality (adjusted HR (95% CI) 0.91 (0.86, 0.97) and 0.87 (0.79, 0.96), respectively). In participants who consumed soy product of ≥ 7 portions/week, the association of higher intake with lower CVD mortality was modestly mediated by total cholesterol (4.2%, 95% CI 1.0-16.6%). Updated meta-analyses showed that the highest level of soy product intake, versus the lowest, was associated with lower risks of all-cause and CVD mortality (pooled HR (95% CI) 0.92 (0.88, 0.96) and 0.92 (0.87, 0.98), respectively). CONCLUSION: Moderate and high soy product intake were associated with lower risks of all-cause and CVD mortality. Our findings provide support for current dietary guidelines recommending moderate soy product intake, and contribute additional evidence regarding the potential protective effects of high soy product intake.

Association of novel and conventional obesity indices with colorectal cancer risk in older Chinese: a 14-year follow-up of the Guangzhou Biobank Cohort Study.

BACKGROUND: Visceral adiposity index (VAI) and a body shape index (ABSI) were newly developed indices for visceral fat mass. Whether they are superior to conventional obesity indices in predicting colorectal cancer (CRC) remains unclear. We examined the associations of VAI and ABSI with CRC risk, and investigated their performance in discriminating CRC risk compared with conventional obesity indices in the Guangzhou Biobank Cohort Study. METHODS: A total of 28,359 participants aged 50 + years without cancer history at baseline (2003-8) were included. CRC were identified from the Guangzhou Cancer Registry. Cox proportional hazards regression was used to assess the association of obesity indices with the CRC risk. Discriminative abilities of obesity indices were assessed using Harrell's C-statistic. RESULTS: During an average follow-up of 13.9 (standard deviation = 3.6) years, 630 incident CRC cases were recorded. After adjusting for potential confounders, the hazard ratio (95% confidence interval) of incident CRC for per standard deviation increment in VAI, ABSI, body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) was 1.04 (0.96, 1.12), 1.13 (1.04, 1.22), 1.08 (1.00, 1.17), 1.15 (1.06, 1.24), 1.16 (1.08, 1.25)and 1.13 (1.04, 1.22), respectively. Similar results for colon cancer were found. However, the associations of obesity indices with risk of rectal cancer were non-significant. All obesity indices showed similar discriminative abilities (C-statistics from 0.640 to 0.645), with WHR showing the highest whilst VAI and BMI the lowest. CONCLUSIONS: ABSI, but not VAI, was positively associated with a higher risk of CRC. However, ABSI was not superior to the conventional abdominal obesity indices in predicting CRC.

Quantity and Variety in Fruit and Vegetable Consumption and Mortality in Older Chinese: A 15-year Follow-Up of a Prospective Cohort Study.

BACKGROUND: Independent associations of quantity and variety of fruit and vegetables (FVs) with mortality in older people are still unclear. OBJECTIVES: This study aimed to explore the association between the quantity and variety in FV consumption and mortality in older Chinese. METHODS: A total of 19,597 participants of the Guangzhou Biobank Cohort Study aged >50 y were recruited from 2003 to 2006 and followed up until April 2021. The diet was assessed using a 300-item validated FFQ. Variety as a continuous variable was defined as the number of unique FV items (excluding potatoes, legumes, and fruit juices) intake per week over the past week. The associations of quantity and variety of FVs with mortality were analyzed, and analyses by the color of edible parts was performed. Multivariable Cox regression yielded HRs and 95% CIs. RESULTS: During 286,821 person-year of follow-up, 4385 deaths occurred, including 1678 cardiovascular diseases (CVD), 1450 cancer, and 1257 other causes. Compared with the lowest quintile of variety in FV, the highest quintile was associated with lower risks of all-cause (HR: 0.81; 95% CI: 0.73-0.89) and CVD mortality (HR: 0.79; 95% CI 0.67-0.92). A greater variety of green and white FV intake was associated with lower risks of all-cause and CVD morality, and a greater variety of red/purple FV intake was associated with lower risks of all-cause and cancer mortality. However, the quantity of FV intake showed no association with all-cause, CVD, and cancer mortality. CONCLUSION: Our findings have first showed that the variety, rather than quantity, in FV intake was associated with a lower risk of mortality in older Chinese. Dietary guidelines may recommend increasing the variety in FV intake, especially green, red/purple, and white FVs in older people.

Cereal intake and mortality in older Chinese: a 15-year follow-up of a prospective cohort study.

PURPOSE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Association of Multi-Dimensional Factors with Accelerating Age and Constructing a Healthy Lifestyle Index: Guangzhou Biobank Cohort Study.

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 socio-economic 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 ß (95% confidence intervals) being 2.75 (2.40-3.09), 1.31 (0.87-1.76), 1.35 (0.55-2.15), 0.64 (0.40-0.88), 0.09 (0.06-0.11), and 0.13 (0.07-0.19) 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 (2.48-3.32) years older AA. CONCLUSIONS: Male sex, smoking, alcohol use, physical inactivity, greater waist circumference, and BMI were associated with higher AA by 0.09-2.75 years, suggesting that adopting a healthy lifestyle may alleviate process of phenotypic ageing.

Association of fish and meat consumption with non-alcoholic fatty liver disease: Guangzhou Biobank Cohort Study.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease. Unhealthy dietary habit is one of major risk factors of NAFLD. However, the associations between specific types of fish and meat consumption and NAFLD remain inconclusive. We explored the associations of fish and meat consumption with NAFLD risk in middle-aged and older Chinese. METHODS: We collected information on 1,862 participants aged 50 years or older from Guangzhou Biobank Cohort Study in 2009 to 2010. Fish and meat consumption was assessed using a validated food-frequency questionnaire. NAFLD was diagnosed by ultrasound. Multivariable logistic regression was used to examine the associations of fish and meat consumption with the presence of NAFLD. RESULTS: The average age was 61.0 (standard deviation = 6.5) years for the participants, 50.2% were women, and 37.2% were diagnosed with NAFLD. After adjusting for age, sex, education, family income, occupation, smoking status, drinking status, physical activity and several metabolic traits, compared with 0 serving/week (one serving = 50 g), fatty fish consumption of ≥ 3 servings/week showed higher odds of NAFLD (odds ratio (OR) and 95% confidence interval (CI): 1.64 (1.12, 2.39)). The highest (≥ 11 servings/week of red meat and poultry; ≥ 3 servings/week of processed meat) versus the lowest (0-3 servings/week of red meat and poultry; 0 serving/week of processed meat) consumption of all other types of meats, including red meat, poultry and processed meat, showed no association with NAFLD (1.17 (0.75, 1.81), 1.02 (0.42, 2.50) and 0.85 (0.50, 1.45), respectively). Aquatic and sea food, and red meat had negative indirect effects on NAFLD via systolic blood pressure and/or high-density lipoprotein cholesterol. Processed meat had positive indirect effects on NAFLD via body mass index, waist circumference, fasting plasma glucose and triglycerides. CONCLUSION: High consumption of fatty fish was associated with higher NAFLD risk. Our results, if causal, provide evidence that limiting consumption of fatty fish can be considered as part of NAFLD lifestyle prevention and treatment.

Associations of face-to-face and non-face-to-face social isolation with all-cause and cause-specific mortality: 13-year follow-up of the Guangzhou Biobank Cohort study.

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.

Life course exposures continually shape antibody profiles and risk of seroconversion to influenza.

Complex exposure histories and immune mediated interactions between influenza strains contribute to the life course of human immunity to influenza. Antibody profiles can be generated by characterizing immune responses to multiple antigenically variant strains, but how these profiles vary across individuals and determine future responses is unclear. We used hemagglutination inhibition titers from 21 H3N2 strains to construct 777 paired antibody profiles from people aged 2 to 86, and developed novel metrics to capture features of these profiles. Total antibody titer per potential influenza exposure increases in early life, then decreases in middle age. Increased titers to one or more strains were seen in 97.8% of participants during a roughly four-year interval, suggesting widespread influenza exposure. While titer changes were seen to all strains, recently circulating strains exhibited the greatest titer rise. Higher pre-existing, homologous titers at baseline reduced the risk of seroconversion to recent strains. After adjusting for homologous titer, we also found an increased frequency of seroconversion against recent strains among those with higher immunity to older previously exposed strains. Including immunity to previously exposures also improved the deviance explained by the models. Our results suggest that a comprehensive quantitative description of immunity encompassing past exposures could lead to improved correlates of risk of influenza infection.

Association of alcohol drinking with incident type 2 diabetes and pre-diabetes: The Guangzhou Biobank Cohort Study.

AIMS: We examined associations of baseline alcohol drinking with incident type 2 diabetes (T2D) or impaired fasting glucose (IFG), and explore whether the associations were modified by genetic polymorphisms of aldehyde dehydrogenase-2 (ALDH2) and alcohol dehydrogenase-1B (ADH1B). MATERIALS AND METHODS: All participants were aged 50+ (mean = 60.45; standard deviation = 6.88) years. Information of alcohol consumption was collected at baseline from 2003 to 2008. Incident T2D 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 T2D and/or initiation of hypoglycaemia medication or insulin during follow-up. Impaired fasting glucose was defined as fasting glucose ≥5.6 mmol/L and <7 mmol/L. RESULTS: Of 15,716 participants without diabetes and 11,232 participants without diabetes and IFG at baseline, 1624 (10.33%) developed incident T2D and 1004 (8.94%) developed incident IFG during an average 4 years of follow-up. After multivariable adjustments, compared with never drinking, occasional or moderate alcohol drinking was not associated with risk of incident hyperglycaemia (T2D + IFG) (odds ratio (OR) = 1.10, 95% confidence interval (CI) 0.95-1.27, and 0.90 (0.69-1.18), respectively), whereas heavy alcohol drinking was associated with a higher risk of incident hyperglycaemia (T2D + IFG) (OR = 1.82, 95% CI 1.24-2.68). No interactions of sex, overweight/obesity and genetic polymorphisms of ADH1B/ALDH2 genes with alcohol drinking on incident T2D and/or IFG were found (P for interaction from 0.12 to 0.85). CONCLUSIONS: Our results support a detrimental effect of heavy alcohol use on IFG and T2D. No protective effect was found for those carrying lower risk alleles for ADH1B/ALDH2 genes.

Association of alcohol use with memory decline in middle-aged and older Chinese: a longitudinal cohort study.

BACKGROUND: Previous studies on associations of alcohol use with memory decline showed inconclusive results. We examined these associations using longitudinal data from the Guangzhou Biobank Cohort Study (GBCS) and explored whether these associations varied by sex and age group. METHODS: Memory function was assessed by delayed 10-word recall test (DWRT) and immediate 10-word recall test (IWRT) at both baseline (2003-2008) and follow-up (2008-2012) examinations, expressed as the mean annual change and mean annual rate of change in scores. Memory cognitive impairment was defined by DWRT scores of less than 4. Multivariable linear regression models and restricted cubic spline were used for data analysis. RESULTS: Of 14,827 participants without memory cognitive impairment at baseline, 90.2% were never or occasional drinkers, 5% moderate drinkers, 1.5% excessive drinkers, and 3.3% former drinkers. The mean (standard deviation) age was 60.6 (6.6) years old. During an average of 4.1 years follow-up, 1000 (6.7%) participants developed memory cognitive impairment. After adjusting for confounders, compared with never or occasional drinkers, moderate and excessive drinkers had significant decline in DWRT scores (ß, 95% confidence interval (CI) = -0.04 (-0.08 to -0.01), and - 0.07 (-0.14 to 0.01), respectively), and IWRT scores (ß, 95% CI = -0.10 (-0.19 to -0.01), and - 0.15 (-0.30 to 0.01), respectively) annually. With respect to the mean annual rate of change, moderate and excessive drinkers also showed greater decline in DWRT scores (ß, 95% CI = -1.02% (-1.87% to -0.16%), and - 1.64% (-3.14% to -0.14%), respectively). The associations did not vary by sex and age group (all P values for interaction ≥ 0.10). CONCLUSION: Compared to never or occasional alcohol use, moderate and excessive alcohol users had greater memory decline and the associations did not vary by sex and age group.

Hearing loss and depressive symptoms in older Chinese: whether social isolation plays a role.

BACKGROUND: Existing evidence links hearing loss to depressive symptoms, with the extent of association and underlying mechanisms remaining inconclusive. We conducted a cross-sectional study to examine the association of hearing loss with depressive symptoms and explored whether social isolation mediated the association. METHODS: Eight thousand nine hundred sixty-two participants from Guangzhou Biobank Cohort Study were included. Data on self-reported hearing status, the 15-item Geriatric Depression Scale (GDS-15), social isolation and potential confounders were collected by face-to-face interview. RESULTS: The mean (standard deviation) age of participants was 60.2 (7.8) years. The prevalence of poor and fair hearing was 6.8% and 60.8%, respectively. After adjusting for age, sex, household income, education, occupation, smoking, alcohol use, self-rated health, comorbidities, compared with participants who had normal hearing, those with poor hearing (ß = 0.74, 95% confidence interval (CI) 0.54, 0.94) and fair hearing (ß = 0.59, 95% CI 0.48, 0.69) had higher scores of GDS-15. After similar adjustment, those with poor hearing (odds ratio (OR) = 2.13, 95% CI 1.65, 2.74) or fair hearing (OR = 1.68, 95% CI 1.43, 1.99) also showed higher odds of depressive symptoms. The association of poor and fair hearing with depressive symptoms attenuated slightly but not substantially after additionally adjusting for social isolation. In the mediation analysis, the adjusted proportion of the association mediated through social isolation was 9% (95% CI: 6%, 22%). CONCLUSION: Poor hearing was associated with a higher risk of depressive symptoms, which was only partly mediated by social isolation. Further investigation of the underlying mechanisms is warranted.

Obesity indicators as mediators of association between daytime napping and type 2 diabetes mellitus: the Guangzhou Biobank Cohort Study.

OBJECTIVE: To examine the mediating effect of obesity indicators on the association between daytime napping and type 2 diabetes mellitus (T2DM) qualitatively and quantitatively using baseline data from the Guangzhou Biobank Cohort Study. METHODS: Twenty-nine thousand three hundred fifty-five participants aged 50+ years were included in this cross-sectional study. Mediation analysis was used to assess the mediating effect of body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) on the association between daytime napping and T2DM after adjustment for sex, age, education, occupation, smoking status, alcohol use and physical activity. RESULTS: The mean (standard deviation) age of participants was 61.5 ( 7.1) years. The prevalence of T2DM and daytime napping was 12.5% and 65.2%, respectively. After adjustment for potential confounders, WC, WHR and WHtR showed partial mediating effects on the association between daytime napping and T2DM, with the proportion (95% confidence interval) of mediation effect being 10.17% (8.14-14.43%), 14.91% (11.95-21.24%) and 9.36% (7.49-13.29%), respectively. No mediating effect of BMI or HC on the association between daytime napping and T2DM was found. CONCLUSIONS: Our results showed significant mediating effects of WC, WHR and WHtR on the association between daytime napping and T2DM, suggesting that waist circumference management could be important in daytime nappers.

Mendelian Randomization Focused Analysis of Vitamin D on the Secondary Prevention of Ischemic Stroke.

BACKGROUND AND PURPOSE: Experimental studies showed vitamin D (Vit-D) could promote vascular regeneration and repair. Prior randomized studies had focused mainly on primary prevention. Whether Vit-D protects against ischemic stroke and myocardial infarction recurrence among subjects with prior ischemic insults was unknown. Here, we dissected through Mendelian randomization any effect of Vit-D on the secondary prevention of recurrent ischemic stroke and myocardial infarction. METHODS: Based on a genetic risk score for Vit-D constructed from a derivation cohort sample (n=5331, 45% Vit-D deficient, 89% genotyped) via high-throughput exome-chip screening of 12 prior genome-wide association study-identified genetic variants of Vit-D mechanistic pathways (rs2060793, rs4588, and rs7041; F statistic, 73; P<0.001), we performed a focused analysis on prospective recurrence of myocardial infarction (MI) and ischemic stroke in an independent subsample with established ischemic disease (n=441, all with prior first ischemic event; follow-up duration, 41.6±14.3 years) under a 2-sample, individual-data, prospective Mendelian randomization approach. RESULTS: In the ischemic disease subsample, 11.1% (n=49/441) had developed recurrent ischemic stroke or MI and 13.3% (n=58/441) had developed recurrent or de novo ischemic stroke/MI. Kaplan-Meier analyses showed that genetic risk score predicted improved event-free survival from recurrent ischemic stroke or MI (log-rank, 13.0; P=0.001). Cox regression revealed that genetic risk score independently predicted reduced risk of recurrent ischemic stroke or MI combined (hazards ratio, 0.62 [95% CI, 0.48-0.81]; P<0.001), after adjusted for potential confounders. Mendelian randomization supported that Vit-D is causally protective against the primary end points of recurrent ischemic stroke or MI (Wald estimate: odds ratio, 0.55 [95% CI, 0.35-0.81]) and any recurrent or de novo ischemic stroke/MI (odds ratio, 0.64 [95% CI, 0.42-0.91]) and recurrent MI alone (odds ratio, 0.52 [95% CI, 0.30-0.81]). CONCLUSIONS: Genetically predicted lowering in Vit-D level is causal for the recurrence of ischemic vascular events in persons with prior ischemic stroke or MI.

Brain-derived neurotrophic factor gene variants and obesity in former smokers.

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) in European, African and Asian population. 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: The study design is case-control study with a cohort validation in supplementary. We included 15,072 ethnic Chinese participants in the Guangzhou Biobank Cohort Study (GBCS) with data of four BDNF SNPs related to both 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 (WC) 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 (3169 men and 11,903 women), 1664 (11.0%) had general and 7868 (52.2%) had central obesity. In 1233 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. The different associations of the SNPs for general/central obesity in different smoke exposure groups may be related to the competitive performance of the sites and epigenetic modification, which needs further study.

Glycaemia and hand grip strength in aging people: Guangzhou biobank cohort study.

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 < 0.001). The association of glycemic status with RGS was non-significant in women. Among the normoglycaemic group, no association was found between fasting glucose and RGS in men, whereas a significantly inverse association was found in women, with adjusted ß for RGS per mmol/l increase in fasting glucose being - 0.05 to - 0.04 (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.

Mendelian randomization estimates of alanine aminotransferase with cardiovascular disease: Guangzhou Biobank Cohort study.

Observational studies of the association of alanine aminotransferase (ALT) levels with ischaemic heart disease (IHD) and cardiovascular disease (CVD) risk factors are inconsistent, probably because of confounding and reverse causality. Mendelian randomization (MR) provides less confounded results. We used MR analysis to assess the associations of ALT (U/L) with IHD, diabetes and other CVD risk factors. We used instrumental variable analysis based on two single nucleotide polymorphism (SNPs) HSD17B13/MAPK10 (rs6834314) and PNPLA3/SAMM50 (rs738409) to assess the associations of ALT (U/L) with IHD, diabetes and other CVD risk factors in the Guangzhou Biobank Cohort Study (GBCS). Observationally in 19,925 participants ALT levels were strongly positively associated with self-reported IHD, systolic and diastolic blood pressure, low-density lipoprotein- and total cholesterol, triglycerides, fasting glucose, body mass index, waist circumference, heart rate (HR) and diabetes, but were not associated with uncorrected QT interval, HR-corrected QT interval or high-density lipoprotein-cholesterol. In the MR study, using a credible genetic instrument (F-statistic = 23) for ALT, ALT levels were negatively associated with IHD (odds ratio (OR) 0.92, 95% confidence interval (CI) 0.87 to 0.97) and triglycerides (ß - 0.08, 95% CI - 0.13 to - 0.03), but were not associated with other CVD risk factors. Our results using Mendelian randomization suggest that ALT reduces the risk of IHD, probably through reducing triglyceride levels. The underlying mechanisms deserve further investigation.

Genetic scores for BMI related to metabolically unhealthy obesity in an older Chinese population.

OBJECTIVE: In this study, a genetic risk score (GRS) for the body mass index (BMI) tested and built using a large sample of Chinese individuals aged at least 50 years in southern China. We collected information regarding the participants' weights at 20 years of age and middle age and tested the BMI-GRS effect modes. METHODS: This study involved a prospective study design. The genetic data of the participants in from the Guangzhou Biobank Cohort Study and selected BMI-related single-nucleotide polymorphisms (SNPs) were used to establish the GRS. RESULTS: We included 13 597 participants with 12 SNPs. After adjusting for covariates, the high-GRS group was 36% (95% CI: 25%-48%) and 34% (95% CI: 23%-47%) more likely of being overweight at baseline and follow-up, respectively, and 56% (95% CI: 34%-82%) and 49% (95% CI: 29%-72%) more likely of being obese at baseline and follow-up, respectively, compared with the low-GRS group (P-value for all trends <.05). The RRs for the incidences of metabolically healthy and unhealthy obese (MHO and MUO, respectively) individuals in the high-GRS group were 0.94 (95% CI: 0.65-1.35) and 1.28 (95% CI: 1.00-1.63), respectively. CONCLUSION: High-GRS participants were more likely to be overweight/obese at baseline and follow-up, and this relationship exhibited a dose-response relationship. The GRS was also associated with MUO.

Egg consumption and the risk of cardiovascular disease and all-cause mortality: Guangzhou Biobank Cohort Study and meta-analyses.

PURPOSE: Eggs are highly nutritious but concerns over their cholesterol content have led to dietary avoidance among many. There are also important international differences in relevant dietary guidance. We conducted the first prospective study in China investigating the association of egg consumption, cardiovascular disease (CVD) mortality, and a meta-analysis. METHODS: We included 28,024 participants without CVD at baseline (2003-8) in Guangzhou Biobank Cohort Study. All-cause and CVD mortality were identified through record linkage. We used Cox proportional hazards regression. We followed the Meta-analysis Of Observational Studies in Epidemiology reporting guidelines. RESULTS: During 275,343 person-years follow-up (average 9.8 years), we found 2685 all-cause and 873 CVD deaths. We found no significant difference in all-cause mortality between higher (7+ eggs/week) and low consumption (< 1 egg/week) [adjusted hazard ratio (HR) 1.08, 95% confidence interval (CI) 0.93-1.24], and mortality from CVD (0.99, 95% CI 0.76-1.27), ischemic heart disease (IHD) (0.92, 95% CI 0.63-1.36), or stroke (0.88, 95% CI 0.57-1.35). The updated meta-analyses including our results showed that 7+ eggs/week was not associated with all-cause mortality (HR 1.09, 95% CI 0.997-1.200) or IHD (HR 0.97, 95% CI 0.90-1.05), but associated with a small reduction in stroke (HR 0.91. 95% CI 0.85-0.98). CONCLUSIONS: Eating one egg daily is not associated with increase in CVD or all-cause mortality. The small observed reduction in stroke risk needs to be confirmed. Our findings support current guidelines recommending eggs as part of a healthy diet, and should be considered in other dietary recommendations.

Sleep quality and cognitive impairment in older Chinese: Guangzhou Biobank Cohort Study.

BACKGROUND: evidence concerning the relationship between sleep quality and cognitive impairment is limited and inconsistent. OBJECTIVE: to examine the association of sleep quality with memory impairment and poor cognitive function in a large sample of older Chinese. METHODS: 15,246 participants aged 50+ years of the Guangzhou Biobank Cohort Study who attended the second physical examination from 2008 to 2012 were included. Sleep quality was assessed using Pittsburgh Sleep Quality Index (PSQI), and cognitive performance was assessed using both Delayed Word Recall Test (DWRT) and Mini-Mental State Examination (MMSE). Memory impairment was defined by DWRT score < 4 and poor cognitive function by MMSE score < 25. RESULTS: after adjusting for potential confounders, lower habitual sleep efficiency was associated with a higher risk of memory impairment and poor cognitive function with a dose-response pattern (both P for trend <0.001). The adjusted odds ratio (OR, 95% confidence interval (CI)) for poor cognitive function in those with the sleep efficiency of 75-85%, 65-75% and <65%, versus ≥85%, was 1.31 (1.12-1.53), 1.41 (1.16-1.73) and 1.33 (1.09-1.63), respectively. No association of the global PSQI score with memory impairment or poor cognitive function was found. CONCLUSIONS: in older Chinese people, lower habitual sleep efficiency was associated with a higher risk of memory impairment and poorer cognitive function.

Estimating the life course of influenza A(H3N2) antibody responses from cross-sectional data.

The immunity of a host population against specific influenza A strains can influence a number of important biological processes, from the emergence of new virus strains to the effectiveness of vaccination programmes. However, the development of an individual's long-lived antibody response to influenza A over the course of a lifetime remains poorly understood. Accurately describing this immunological process requires a fundamental understanding of how the mechanisms of boosting and cross-reactivity respond to repeated infections. Establishing the contribution of such mechanisms to antibody titres remains challenging because the aggregate effect of immune responses over a lifetime are rarely observed directly. To uncover the aggregate effect of multiple influenza infections, we developed a mechanistic model capturing both past infections and subsequent antibody responses. We estimated parameters of the model using cross-sectional antibody titres to nine different strains spanning 40 years of circulation of influenza A(H3N2) in southern China. We found that "antigenic seniority" and quickly decaying cross-reactivity were important components of the immune response, suggesting that the order in which individuals were infected with influenza strains shaped observed neutralisation titres to a particular virus. We also obtained estimates of the frequency and age distribution of influenza infection, which indicate that although infections became less frequent as individuals progressed through childhood and young adulthood, they occurred at similar rates for individuals above age 30 y. By establishing what are likely to be important mechanisms driving epochal trends in population immunity, we also identified key directions for future studies. In particular, our results highlight the need for longitudinal samples that are tested against multiple historical strains. This could lead to a better understanding of how, over the course of a lifetime, fast, transient antibody dynamics combine with the longer-term immune responses considered here.