Fruit and vegetable consumption and cardiovascular risk factors in older Chinese: The Guangzhou Biobank Cohort Study

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Systematic differences among never, occasional and moderate alcohol users in southern China, and its use in alcohol research: a cross-sectional study

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Evaluation of moderate alcohol use and cognitive function among men using a mendelian randomization design in the guangzhou biobank cohort study

Observational studies usually show that moderate alcohol use is associated with better cognitive function. Such studies are vulnerable to residual confounding arising from systematic differences between moderate alcohol users and others. A Mendelian randomization study carried out in a suitable population, such as southern Chinese men, in which alcohol use is low to moderate and is influenced by genotype, offers an alternative and superior approach for clarifying the causal effect of moderate alcohol use on cognitive function. The authors used aldehyde dehydrogenase 2 (ALDH2) genotype (AA, GA, or GG) as an instrumental variable in 2-stage least squares analysis to obtain unbiased estimates of the relation of alcohol consumption (measured in alcohol units (10 g ethanol) per day) with cognitive function, assessed from delayed 10-word recall score (n = 4,707) and Mini-Mental State Examination (MMSE) score (n = 2,284), among men from the Guangzhou Biobank Cohort Study (2003-2008). ALHD2 genotype was strongly associated with alcohol consumption, with an F statistic of 71.0 in 2-stage least squares analysis. Alcohol consumption was not associated with delayed 10-word recall score (-0.03 words per alcohol unit, 95% confidence interval:-0.18, 0.13) or MMSE score (0.06 points per alcohol unit, 95% confidence interval:-0.22, 0.34). Moderate alcohol use is unlikely to be cognitively protective. © The Author 2012. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved.postprin

Life-course origins of social inequalities in adult immune cell markers of inflammation in a developing southern Chinese population: the Guangzhou Biobank Cohort Study

BACKGROUND: Socioeconomic position (SEP) throughout life is associated with cardiovascular disease, though the mechanisms linking these two are unclear. It is also unclear whether there are critical periods in the life course when exposure to better socioeconomic conditions confers advantages or whether SEP exposures accumulate across the whole life course. Inflammation may be a mechanism linking socioeconomic position (SEP) with cardiovascular disease. In a large sample of older residents of Guangzhou, in southern China, we examined the association of life course SEP with inflammation. METHODS: In baseline data on 9,981 adults (>/= 50 years old) from the Guangzhou Biobank Cohort Study (2006-08), we used multivariable linear regression and model fit to assess the associations of life course SEP at four stages (childhood, early adult, late adult and current) with white blood, granulocyte and lymphocyte cell counts. RESULTS: A model including SEP at all four life stages best explained the association of life course SEP with white blood and granulocyte cell count for men and women, with early adult SEP (education) making the largest contribution. A critical period model best explained the association of life course SEP with lymphocyte count, with sex-specific associations. Early adult SEP was negatively associated with lymphocytes for women. CONCLUSIONS: Low SEP throughout life may negatively impact late adult immune-inflammatory status. However, some aspects of immune-inflammatory status may be sensitive to earlier exposures, with sex-specific associations. The findings were compatible with the hypothesis that in a developing population, upregulation of the gonadotropic axis with economic development may obscure the normally protective effects of social advantage for men.published_or_final_versio

Parental death during childhood and adult cardiovascular risk in a developing country: The Guangzhou Biobank Cohort study

Background: In observational studies from western countries childhood emotional adversity is usually associated with adult cardiovascular disease. These findings are open to contextual biases making evidence from other settings valuable. We examined the association of a potential marker of childhood emotional adversity with cardiovascular disease risk factors in a developing country. Methods: We used multivariable regression in cross-sectional analysis of older (≥50 years) men (n = 7,885) and women (n = 20,886) from the Guangzhou Biobank Cohort Study (2003-8) to examine the adjusted association of early life (<18 years) parental death (none, one or two deaths) with blood pressure, fasting glucose, LDL-cholesterol, HDL-cholesterol, triglycerides, body mass index (BMI), waist-hip ratio (WHR) and white blood cell count (WBC). We used seated height and delayed 10-word recall to assess content validity of parental death as a measure of childhood emotional adversity. We also examined whether associations varied by sex. Results: Early life parental death was associated with shorter age- and sex-adjusted seated height. It was also associated with lower 10-word recall score adjusted for age, sex, socio-economic position, leg length and lifestyle. Similarly, adjusted early life parental death was not associated with blood pressure, fasting glucose, LDL-cholesterol or HDL-cholesterol but was associated with lower BMI (-0.40, 95% confidence interval (CI) -0.62 to -0.19 for 2 compared with no early life parental deaths) and triglycerides. Associations varied by sex for WHR and WBC. Among men only, early life parental death was associated with lower WHR (-0.008, 95% CI -0.015 to -0.001) and WBC (-0.35 10 9/L, 95% CI -0.56 to -0.13). Conclusions: In a non-western population from a developing country, childhood emotional adversity was negatively associated with some cardiovascular risk factors, particularly among men. Our study suggests that some of the observed associations in western populations may be socially rather than biologically based or may be population specific. © 2011 Schooling et al.published_or_final_versio

Moderate alcohol use and cardiovascular disease from mendelian randomization

Background Observational studies show moderate alcohol use negatively associated with ischemic heart disease (IHD) and cardiovascular disease (CVD). However, healthier attributes among moderate users compared to never users may confound the apparent association. A potentially less biased way to examine the association is Mendelian randomization, using alcohol metabolizing genes which influence alcohol use. Methods We used instrumental variable analysis with aldehyde dehydrogenase 2 (ALDH2) genotypes (AA/GA/GG) as instrumental variables for alcohol use to examine the association of alcohol use (10 g ethanol/day) with CVD risk factors (blood pressure, lipids and glucose) and morbidity (self-reported IHD and CVD) among men in the Guangzhou Biobank Cohort Study. Results ALDH2 genotypes were a credible instrument for alcohol use (F-statistic 74.6). Alcohol was positively associated with HDL-cholesterol (0.05 mmol/L per alcohol unit, 95% confidence interval (CI) 0.02 to 0.08) and diastolic blood pressure (1.15 mmHg, 95% CI 0.23 to 2.07) but not with systolic blood pressure (1.00 mmHg, 95% CI -0.74 to 2.74), LDL-cholesterol (0.03 mmol/L, 95% CI -0.03 to 0.08), log transformed triglycerides (0.03 mmol/L, 95% CI -0.01 to 0.08) or log transformed fasting glucose (0.01 mmol/L, 95% CI -0.006 to 0.03), self-reported CVD (odds ratio (OR) 0.98, 95% CI 0.76 to 1.27) or self-reported IHD (OR 1.10, 95% CI 0.83 to 1.45). Conclusion Low to moderate alcohol use among men had the expected effects on most CVD risk factors but not fasting glucose. Larger studies are needed to confirm the null associations with IHD, CVD and fasting glucose.published_or_final_versio

Aldehyde dehydrogenase 2-a potential genetic risk factor for lung function among southern Chinese: Evidence from the Guangzhou Biobank Cohort Study

Purpose: In Asia, moderate alcohol users have better lung function. Never users have more inactive aldehyde dehydrogenase 2 (ALDH2) alleles (A) potentially generating confounding because inactive alleles may increase acetaldehyde exposure and reduce lung function. Methods: We examined the association of ALDH2 genotypes with percentage predicted lung function (forced expiratory volume in 1second; forced vital capacity) for age, sex, and height among 5641 older Chinese using multivariable linear regression. Results: ALDH2 genotypes were associated with alcohol use and height but not other attributes. Inactive alleles were inversely associated with lung function (percentage predicted forced expiratory volume in 1second-1.52%, 95% confidence interval [CI],-2.52% to-0.51% for one inactive allele and-2.05%, 95% CI,-3.85% to-0.26% for two inactive alleles compared with two active alleles; and for percentage predicted forced vital capacity-1.25%, 95% CI-2.15% to-0.35% and-1.65%, 95% CI,-3.25% to-0.04%). The association of moderate use with lung function was attenuated after adjusting for ALDH2, in addition to other potential confounders. Conclusions: Previous findings in Chinese may be confounded by ALDH2. High frequency of inactive ALDH2 alleles in East Asia may exacerbate the effect of environmental acetaldehyde exposure on lung function and potentially on chronic obstructive pulmonary disease. © 2014 Elsevier Inc.postprin

Systematic differences among never, occasional and moderate alcohol users in southern China, and its use in alcohol research: a cross-sectional study

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Immunogenetics in SARS: a case-control study.

Key Messages: 1. Human leukocyte antigen (HLA) genotypes from 102 SARS patients (susceptible) and 108 SARS contacts (resistant) were obtained. 2. Allelic frequencies of the Class I (HLA-A, -B, and -Cw) and Class II (HLA-DR and -DQ) genes from these genetically unrelated subjects were compared. 3. A significantly higher frequency of DRB4*01010101 was found in the SARS-susceptible than SARS-resistant group. In contrast, significantly higher frequencies of HLA-B*1502 and HLADRB3*030101 were found in the SARS-resistant than SARSsusceptible group. However, none of these associations was significant after Bonferroni correction. Further, analysis of 10/36 genetically related families did not reveal any HLA alleles associated with SARS susceptibility or resistance. 4. We could not confirm previous findings of an HLA association with susceptibility or resistance to SARS. The significance of these associations needs to be validated by further independent studies.published_or_final_versio

Is better nutrition in childhood in a developing population associated with better cognitive function in later adulthood?: The Guangzhou Biobank Cohort Study

Objective: There is growing evidence that early life exposures, such as childhood socioeconomic status, are related to later adulthood cognition. However, the specific aspect of early conditions underlying this association is not clear. Animal protein intake is positively associated with earlier walking in infants. Dietary supplementation with meat in infants and children in developing countries results in better cognitive function, independent of iron status. Protein energy supplementation with vegetables, milk and sugar (not meat) given from birth to 24 months in developing populations is associated with better cognitive function in early adulthood (mean age 32 years), especially amongst women. Inadequate childhood nutrition is associated with poor short term academic and cognitive outcomes. However, it is not known whether childhood nutrition has life long effects on cognitive function. We examined the association of childhood meat eating with adulthood cognitive function in southern China where the older population lived through significant hardship during their early years. Methods: Multivariable linear regression was used in a crosssectional study of 20,086 Chinese men and women aged >50 years from the Guangzhou Biobank Cohort Study (phases 2 and 3) 2005–8. We assessed the association of childhood meat eating with amnesic-MCI and delayed 10-word recall score. The 10-word recall is a test of new learning ability from the CERAD (Consortium to Establish a Registry for Alzheimer’s Disease) test battery which has been validated as a culturally and educationally sensitive tool for identifying dementia in population based research in developing countries. Amnesic-MCI was defined as a delayed recall score of 3 or less out of 10, corresponding to 1 standard deviation below the mean. Results: Adjusted for age, sex and education, childhood meat eating 1–6 days per week and daily childhood meat eating were associated with a higher 10-word recall score (number of words recalled 50.08 [95% confidence interval50.02 to 0.13] and 0.24 [0.16 to 0.33] respectively) and with lower odds of amnesic-MCI (odds ratio50.80 [95% confidence interval50.72 to 0.89] and 0.79 [0.67 to 0.94] respectively). Additional adjustment for childhood and adulthood socio economic position and current physical activity attenuated these findings, however daily childhood meat eating remained associated with a higher 10-word recall score (0.17 [0.08 to 0.26]. Conclusions: A diet that includes a small amount of daily meat in childhood (after infancy) may have long-term positive effects on cognitive function. If confirmed, these results highlight the importance of adequate childhood nutrition. Alternatively childhood meat eating may reflect a generally more cognitively protective childhood environment and nutrition. Irrespective, these findings also emphasise the childhood and adolescent antecedents of adult disease, with corresponding public health implications for healthy aging. Future research should examine the role of childhood exposures in long term cognitive development and if a role for childhood meat eating is verified, should elucidate the type and quantity of macro and micro nutrients that may be cognitively protective and the biological mechanisms behind these effects, so that preventive strategies can be implemented. Acknowledgements: The University of Hong Kong (HKSAR), Guangzhou Public Health Bureau (China), Guangzhou Science and Technology Bureau (China), The University of Birmingham (UK).published_or_final_versio