Adiposity and incident diabetes within 4 years of follow-up: the Guangzhou Biobank Cohort Study

AIM

Whether different adiposity measures predict incident diabetes differentially in general Chinese populations is unclear. We investigated this in Chinese people aged 50+ years in the Guangzhou Biobank Cohort Study.

METHODS

Waist circumference and BMI were measured at baseline, and fasting glucose was measured at both baseline and follow-up examinations. Incident diabetes was defined as fasting glucose ≥ 7.0 mmol/l, glucose after 2-h oral glucose tolerance test ≥ 11.1 mmol/l, and/or self-reported physician-diagnosed diabetes during the follow-up period.

RESULTS

Of 15 752 people without diabetes at baseline from 2003 to 2008, 1779 (11.3%) developed incident diabetes during the follow-up from 2008 to 2012 (mean = 3.6 years, sd = 1.0). After mutually adjusting each other and adjusting for other potential confounders, waist circumference showed a higher predictive value than BMI. The odds ratio (OR) (95% confidence interval (CI) was 1.50 (95% CI 1.37-1.64) for a 1 sd increment in waist circumference and 1.21 (95% CI 1.11-1.33), for a 1 sd increment in BMI. Similarly, after mutual adjustment, abdominal obesity was associated with an almost twofold odds of incident diabetes (OR 1.93, 95% CI 1.71-2.17), which was higher than that for general obesity (OR 1.76, 95% CI 1.50-2.06). The area under receiver operating characteristic curve (AUC) for waist circumference was higher than that for BMI [AUC = 0.676 (95% CI 0.660-0.686) vs. 0.665 (95% CI 0.651-0.678), P = 0.02].

CONCLUSION

Abdominal obesity predicted incident diabetes in older people better than general obesity. Our findings may be an early warning signal for local government or public health practitioners to develop and investigate more effective intervention programmes for diabetes, and should also be disseminated to the public to pay more attention to this important public health issue.

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 (β - 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.

Does tea consumption during early pregnancy have an adverse effect on birth outcomes?

BACKGROUND

Tea, a common beverage, has been suggested to exhibit a number of health benefits. However, one of its active ingredients, caffeine, has been associated with preterm birth and low birthweight. We investigated whether tea consumption during early pregnancy is associated with an increased risk of preterm birth and abnormal fetal growth.

METHODS

A total of 8775 pregnant women were included from the Born in Guangzhou Cohort Study. Tea consumption (type, frequency, and strength) during their first trimester and social and demographic factors were obtained by way of questionnaires administered during pregnancy. Information on birth outcomes and complications during pregnancy was obtained from hospital medical records.

RESULTS

Overall habitual tea drinking (≥1 serving/week) prevalence among pregnant women was low, at 16%. After adjustment for potential confounding factors (eg, maternal age, educational level, monthly income) tea drinking during early pregnancy was not associated with an increased risk of preterm birth or abnormal fetal growth (small or large for gestational age) (P>.05).

CONCLUSIONS

We did not identify a consistent association between frequency of tea consumption or tea strength and adverse birth outcomes among Chinese pregnant women with low tea consumption. Our findings suggest that occasional tea drinking during pregnancy is not associated with increased risk of preterm birth or abnormal fetal growth. Given the high overall number of annual births in China, our findings have important public health significance.

Promoting smoking cessation in China: a foot-in-the-door approach to tobacco control advocacy

INTRODUCTION

The Chinese government's implementation of the MPOWER policies and compliance with the WHO Framework Convention on Tobacco Control requirements has been slow. We used the 'foot-in-the-door' approach to promote tobacco control advocacy through capacity building of healthcare leaders, and establishment of smoking cessation clinics in Guangzhou and Beijing (two of the largest cities in China).

METHODS

This collaborative pilot project involved the University of Hong Kong and three major hospitals in Guangzhou and Beijing. A steering committee conducted the smoking cessation training workshops starting from April 2006, and set up three smoking cessation model clinics during August 2006 to October 2008. We followed up the trained health care professionals (HCPs) in 2014 and 2015 to assess their impacts on tobacco control beyond smoking cessation.

RESULTS

We emphasized the importance of the general tobacco control atmosphere during smoking cessation training of 139 HCPs to motivate them to engage in tobacco control advocacy. In addition to enhancing their knowledge and skills in cessation, the HCPs were then involved in the establishment of three in-hospital smoking cessation clinics and served as smoking cessation counselors since June 2008. Moreover, they ventured outside the clinics and the community to publicize smoking cessation. Their effort has contributed to smoke-free legislation, better surveillance on smoking and media advocacy on tobacco control in China.

CONCLUSIONS

The training and establishment of smoking cessation clinics could serve as a means to motivate and empower HCPs who could contribute to broaden tobacco control policy in China.

Protocol for a nationwide survey of primary health care in China: the China PEACE (Patient-centered Evaluative Assessment of Cardiac Events) MPP (Million Persons Project) Primary Health Care Survey

INTRODUCTION

China has pioneered advances in primary health care (PHC) and public health for a large and diverse population. To date, the current state of PHC in China has not been subjected to systematic assessments. Understanding variations in primary care services could generate opportunities for improving the structure and function of PHC.

METHODS AND ANALYSIS

This paper describes a nationwide PHC study (PEACE MPP Primary Health Care Survey) conducted across 31 provinces in China. The study leverages an ongoing research project, the China Patient-centered Evaluative Assessment of Cardiac Events (PEACE) Million Persons Project (MPP). It employs an observational design with document acquisition and abstraction and in-person interviews. The study will collect data and original documents on the structure and financing of PHC institutions and the adequacy of the essential medicines programme; the education, training and retention of the PHC workforce; the quality of care; and patient satisfaction with care. The study will provide a comprehensive assessment of current PHC services and help determine gaps in access and quality of care. All study instruments and documents will be deposited in the Document Bank as an open-access source for other researchers.

ETHICS AND DISSEMINATION

The central ethics committee at the China National Centre for Cardiovascular Disease (NCCD) approved the study. Written informed consent has been obtained from all patients. Findings will be disseminated in future peer reviewed papers, and will inform strategies aimed at improving the PHC in China.

TRIAL REGISTRATION NUMBER

NCT02953926.

Age at menarche and cardiovascular risk factors using Mendelian randomization in the Guangzhou Biobank Cohort Study

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

Prevalence of adiposity and its association with sleep duration, quality, and timing among 9-12-year-old children in Guangzhou, China

BACKGROUND

Short sleep duration has been reported to be associated with obesity in children, but findings are not consistent. Since few studies have examined the relationship between more complex sleep characteristics and obesity, we examined the association between adiposity and self-reported sleep duration, bedtime, and sleep quality in 9-12-year-old Chinese children using multilevel mixed models.

METHODS

5518 children aged 9-12 years were recruited from 29 randomly selected primary schools in Guangzhou, China in 2014. Standardized questionnaires were used to obtain data to estimate sleep duration on typical weekdays and weekends. Sleep quality data were collected using the Children's Sleep Habits Questionnaire (CSHQ). Trained researchers undertook measurements of weight, height, and waist circumference (WC) for all participating children. Body mass index (BMI) z-scores were derived using the World Health Organization (WHO) child growth reference, and children were classified as overweight or obese using +1 and +2 SD as cut-offs, respectively. Percentage body fat (BF%) was calculated using bioelectrical impedance.

RESULTS

Longer sleep duration was inversely associated with BMI z-score (β = -0.16, p < 0.05), WC (β = -1.11, p < 0.05) and later bedtime was associated with higher BMI z-score (β = 0.03, p < 0.05), WC (β = 1.72, p < 0.001), and BF% (β = 0.15, p < 0.05) in multivariable multilevel mixed models, after adjustment for age, gender, physical activity, parental education level, and average monthly income. No association was seen between sleep quality and adiposity.

CONCLUSION

Shorter sleep duration and later bedtime are associated with higher adiposity indices in early adolescents from southern China.

All-Cause Mortality in Patients With Diabetes Under Treatment With Dapagliflozin: A Population-Based, Open-Cohort Study in The Health Improvement Network Database

CONTEXT

Empagliflozin was found to decrease mortality in patients with type 2 diabetes mellitus (T2DM) and a prior cardiovascular disease (CVD) event.

OBJECTIVES

To establish whether these benefits can be replicated in a real-world setting, should be expected with the use of dapagliflozin, and apply to T2DM patients at low risk of CVD.

DESIGN

General practice, population-based, retrospective cohort study (January 2013 to September 2015).

SETTING

The Health Improvement Network database.

PARTICIPANTS

A total of 22,124 T2DM patients (4444 exposed to dapagliflozin; 17,680 unexposed T2DM patients) matched for age, sex, body mass index, T2DM duration, and smoking.

MAIN OUTCOME MEASURES

The primary outcome was all-cause mortality (high and low risk for CVD) in the total study population, expressed as the adjusted incidence rate ratio (aIRR) with 95% confidence intervals (CIs). As a secondary analysis in the low-risk population, all-cause mortality and incident CVD were considered.

RESULTS

Patients with T2DM exposed to dapagliflozin were significantly less likely to die of any cause (aIRR: 0.50; 95% CI: 0.33 to 0.75; P = 0.001). Similarly, in low-risk patients, death from any cause was significantly lower in the cohort exposed to dapagliflozin (aIRR: 0.44; 95% CI: 0.25 to 0.78; P = 0.002). The difference in the risk of incident CVD did not reach statistical significance between groups in low-risk patients (aIRR: 0.89; 95% CI: 0.61 to 1.31; P = 0.546).

CONCLUSIONS

Patients with T2DM who were exposed to dapagliflozin had a lower risk of death from any cause irrespective of baseline CVD status.

UroMark-a urinary biomarker assay for the detection of bladder cancer

Background

Bladder cancer (BC) is one of the most common cancers in the western world and ranks as the most expensive to manage, due to the need for cystoscopic examination. BC shows frequent changes in DNA methylation, and several studies have shown the potential utility of urinary biomarkers by detecting epigenetic alterations in voided urine. The aim of this study is to develop a targeted bisulfite next-generation sequencing assay to diagnose BC from urine with high sensitivity and specificity.

Results

We defined a 150 CpG loci biomarker panel from a cohort of 86 muscle-invasive bladder cancers and 30 normal urothelium. Based on this panel, we developed the UroMark assay, a next-generation bisulphite sequencing assay and analysis pipeline for the detection of bladder cancer from urinary sediment DNA. The 150 loci UroMark assay was validated in an independent cohort (n = 274, non-cancer (n = 167) and bladder cancer (n = 107)) voided urine samples with an AUC of 97%. The UroMark classifier sensitivity of 98%, specificity of 97% and NPV of 97% for the detection of primary BC was compared to non-BC urine.

Conclusions

Epigenetic urinary biomarkers for detection of BC have the potential to revolutionise the management of this disease. In this proof of concept study, we show the development and utility of a novel high-throughput, next-generation sequencing-based biomarker for the detection of BC-specific epigenetic alterations in urine.

Electronic supplementary material

The online version of this article (doi:10.1186/s13148-016-0303-5) contains supplementary material, which is available to authorized users.

Relationship between weight status and health-related quality of life in Chinese primary school children in Guangzhou: a cross-sectional study

BACKGROUND

To investigate the association between weight status and health-related quality of life (HRQOL) among pupils in Guangzhou, China.

METHODS

The study comprised 5781 children aged 8-12 years from 29 schools. Height and weight were objectively measured using standardized methods, and BMI z-score derived using the age and sex specific WHO reference 2007 for 5-19 years. Weight status was classified as underweight (<-2SD), healthy weight (between -2SD and 1SD), overweight/obesity (>1SD). HRQOL was measured by the self-report version of the Pediatric Quality of Life Inventory 4.0.

RESULTS

After controlling for gender, age, school type, parental education, and family income, HRQOL scores were significantly lower in overweight/obese compared with healthy weight children only in the social functioning domain (β = -1.93, p = 0.001). Compared with healthy weight children, underweight children had significantly lower total (β = -1.47, p = 0.05) and physical summary scores (β = -2.18, p = 0.02). Subgroup analysis for gender indicated that compared to healthy weight, total (β = -1.96, p = 0.02), psychosocial (β = -2.40, p = 0.01), social functioning (β = -3.36, p = 0.001), and school functioning (β = -2.19, p = 0.03) scores were lower in overweight/obese girls, but not boys. On the other hand, being underweight was associated with lower physical functioning (β = -2.27, p = 0.047) in girls, and lower social functioning (β = -3.63, p = 0.01) in boys. The associations were mainly observed in children aged 10 and over, but were not significant in younger children. Children from private schools had generally lower HRQOL compared to those in public schools, but the associations with weight status were similar in both groups.

CONCLUSIONS

The relationship between overweight/obesity and HRQOL in children in China is not as prominent as that seen in children in western or high-income countries. However, there appears to be gender and age differences, with more of an impact of overweight on HRQOL in girls and older children compared with boys and younger children. Underweight is also associated with lower HRQOL. Future intervention to prevent both obesity and undernutrition may have a positive impact on the HRQOL in children in China.

Exposure to secondhand smoke and risk of peripheral arterial disease in southern Chinese non-smokers: The Guangzhou Biobank Cohort Study-Cardiovascular Disease Sub-cohort

Objectives

We studied the association between secondhand smoke (SHS) exposure and peripheral arterial disease (PAD) in Chinese non-smokers.

Methods

We conducted a cross-sectional study using baseline data from the Guangzhou Biobank Cohort Study: Cardiovascular Disease Sub-cohort Study (GBCS-CVD). Guangzhou residents aged ≥ 50 years were recruited between 2003 and 2008. Baseline data included measurement of ankle brachial pressure index (ABPI) and self-reported smoking status and SHS exposure. Univariate and multivariate logistic regression analyses were used to analyze the association between SHS and PAD (defined as ABPI < 0.9).

Results

Of the 1507 non-smokers, 24 (1.6%) had PAD. Of these, 12 were men and 12 were women. Exposure to SHS at home of ≥25 h per week was reported by 16.7% of PAD cases compared with 3.8% of those without PAD (χ2 test, p = 0.003). After adjustment for potential confounders, exposure to ≥25 h per week at home was still associated with PAD (adjusted OR 7.86, 95% CI 2.00–30.95, p = 0.003), with suggestion of a dose-response relationship.

Conclusions

Our results extend the US Surgeon General’s 2006 report that SHS exposure is an independent risk factor for PAD. National smoke-free legislation is needed to protect all people from exposure.

Changes in adiposity in an older Chinese population in rapid economic transition

OBJECTIVE

To examine the changes in body mass index (BMI) and waist circumference (WC) in Guangzhou, South China, which is probably experiencing the most rapid economic transition in history.

METHODS

In this study, 17,786 Chinese aged 50+ years were recruited from 2003 to 2008 and followed up until 2012. BMI and WC were measured at two time points.

RESULTS

During the mean follow-up of 3.6 years (median = 3, interquartile = 1), age-adjusted mean BMI increased only slightly. By contrast, mean WC increased sharply by 0.94 cm (95% confidence interval 0.93-0.94) annually in men and 1.29 cm (1.28-1.29) annually in women. In 77% of women and 69% of men, WC increased, and among them, the mean annual increase was 2.01 cm and 1.70 cm, respectively. Among healthy, never-smoking participants, the incidence of central obesity was 29.0% (36.4% in women and 14.2% in men). The incidence of general obesity was 1.9% and was similarly low in both men and women (2.1% vs. 1.8%). Conversely, 20.3% of individuals with general obesity became nonobese, and 12.8% of individuals with central obesity returned to normal.

CONCLUSIONS

Central obesity has risen sharply in this cohort. Such increases may have been greatly underestimated previously and should form the basis of an even stronger warning for regions undergoing economic transitions in China and elsewhere.

Genomic complexity of urothelial bladder cancer revealed in urinary cfDNA

Urothelial bladder cancers (UBCs) have heterogeneous clinical characteristics that are mirrored in their diverse genomic profiles. Genomic profiling of UBCs has the potential to benefit routine clinical practice by providing prognostic utility above and beyond conventional clinicopathological factors, and allowing for prediction and surveillance of treatment responses. Urinary DNAs representative of the tumour genome provide a promising resource as a liquid biopsy for non-invasive genomic profiling of UBCs. We compared the genomic profiles of urinary cellular DNA and cell-free DNA (cfDNA) from the urine with matched diagnostic formalin-fixed paraffin-embedded tumour DNAs for 23 well-characterised UBC patients. Our data show urinary DNAs to be highly representative of patient tumours, allowing for detection of recurrent clinically actionable genomic aberrations. Furthermore, a greater aberrant load (indicative of tumour genome) was observed in cfDNA over cellular DNA (P<0.001), resulting in a higher analytical sensitivity for detection of clinically actionable genomic aberrations (P<0.04) when using cfDNA. Thus, cfDNA extracted from the urine of UBC patients has a higher tumour genome burden and allows greater detection of key genomic biomarkers (90%) than cellular DNA from urine (61%) and provides a promising resource for robust whole-genome tumour profiling of UBC with potential to influence clinical decisions without invasive patient interventions.

Genetically predicted 17beta-estradiol, cognitive function and depressive symptoms in women: A Mendelian randomization in the Guangzhou Biobank Cohort Study

OBJECTIVE

The role of estrogen in cognitive function and depressive symptoms is controversial due to discrepancies between results from randomized controlled trials (RCT) and observational studies. Mendelian randomization analysis may provide further insights concerning the role of estrogen in these outcomes as it assesses the effect of lifelong endogenous exposure but is less vulnerable to confounding than observational studies.

METHOD

We used separate sample instrumental variable analysis to estimate the association of log 17β estradiol with cognitive function (Delayed 10 word recall, and Mini Mental State Examination (MMSE)) and depressive symptoms (Geriatric Depression Scale (GDS)) in older Chinese women of the Guangzhou Biobank Cohort Study (GBCS, n=3086). The estimate was derived based on the Wald estimator, the ratio of the association of genetic determinants (rs1008805 and rs2175898) of log 17β-estradiol with cognitive function and depressive symptoms in GBCS and the association of log 17β-estradiol with genetic determinants in the sample of young women in Hong Kong (n=236).

RESULTS

Genetically predicted 17β-estradiol was not associated with delayed 10-word recall (0.42 words per log increase in 17β-estradiol (pmol/L), 95% confidence interval (CI) -0.49 to 1.34) MMSE (0.39 per log increase in 17β-estradiol (pmol/L), 95% CI -0.87 to 1.65) or GDS (0.24 per log increase in 17β-estradiol (pmol/L), 95% CI -0.57 to 1.05).

CONCLUSION

These results were largely consistent with evidence from RCTs and did not show any beneficial effect of estrogen on cognitive function and depressive symptoms. However, larger Mendelian randomization analyses are needed to identify any minor effects.

Smoking and serum vitamin D in older Chinese people: cross-sectional analysis based on the Guangzhou Biobank Cohort Study

OBJECTIVE

Studies on serum vitamin D in smokers showed conflicting results. We examined the association of smoking status with serum vitamin D in older Chinese men, taking advantage of a community-based sample with natural exposure to vitamin D.

DESIGN

Cross-sectional study based on the Guangzhou Biobank Cohort Study (GBCS).

SETTING

Community-based sample from the Guangzhou Biobank Cohort Study.

PARTICIPANTS

612 male participants aged 50+years recruited from 2009 to 2011.

RESULTS

The mean (SD) of vitamin D concentration was 58.3 (17.2), 57.0 (15.0) and 54.7 (15.4) nmol/L for never, former and current smokers, respectively. Adjusted for multiple confounders, vitamin D decreased from never to former, then to current smokers (P for trend 0.02). Compared to never smokers, current smokers had lower serum concentrations of vitamin D, and the concentrations decreased with the increasing number of cigarettes per day (-3.11 (95% CI -9.05 to 2.82), -3.29 (-8.3 to 1.72) and -4.61 (-8.89 to -0.33) for 1-9, 10-19 and 20+cigarettes per day, respectively; p for trend 0.01), duration of smoking (-1.39 (-6.09 to 3.30) and -5.39 (-9.42 to -1.35) for 1-39 and 40+years, respectively; p for trend 0.008) as well as pack-years (-2.89 (-6.78 to 1.01) and -5.58 (-10.48 to -0.67) for 1-39 and 40+pack-years, respectively; p for trend 0.009). Longer duration of quitting smoking was associated with higher vitamin D than was current smoking (P for trend 0.04).

CONCLUSIONS

Current smokers had lower vitamin D than never smokers, and the association showed a dose-response pattern.

Socioeconomic determinants of childhood obesity among primary school children in Guangzhou, China

Background

Socioeconomic inequalities in childhood obesity prevalence differ according to a country’s stage of nutrition transition. The aim of this study was to determine which socioeconomic factors influence inequalities in obesity prevalence in Chinese primary school children living in an urban setting.

Methods

We assessed obesity prevalence among 9917 children aged 5–12 years from a stratified random sample of 29 state-funded (residents) and private (migrants) schools in Guangzhou, China. Height and weight were objectively measured using standardised methods and overweight (+1 SD < BMI-for-age z-score ≤ +2 SD) and obesity (BMI-for-age z-score > +2 SD) were defined using the World Health Organisation reference 2007. Socioeconomic characteristics were ascertained through parental questionnaires. Generalised Linear Mixed Models with schools as a random effect were used to compare likelihood of overweight/obesity among children in private, with public schools, adjusting for child age and sex, maternal and paternal BMI and education level, and household per-capita income.

Results

The prevalence of overweight/obesity was 20.0 % (95 % CI 19.1 %–20.9 %) in resident compared with 14.3 % (95 % CI 13.0 %–15.4 %) in migrant children. In the adjusted model, the odds of overweight/obesity remained higher among resident children (OR 1.36; 1.16–1.59), was higher in boys compared with girls (OR 2.56; 2.24–2.93), and increased with increasing age (OR 2.78; 1.95–3.97 in 11–12 vs 5–6 year olds), per-capita household income (OR 1.27; 1.01–1.59 in highest vs lowest quartile) and maternal education (OR 1.51; 1.16–1.97 in highest vs lowest). Socioeconomic differences were most marked in older boys, and were only statistically significant in resident children.

Conclusions

The socioeconomic gradient for childhood obesity in China is the reverse of the patterns seen in countries at more advanced stages of the obesity epidemic. This presents an opportunity to intervene and prevent the onset of social inequalities that are likely to ensue with further economic development. The marked gender inequality in obesity needs further exploration.

Stress across the life course and depression in a rapidly developing population: the Guangzhou Biobank Cohort Study

OBJECTIVE

The objective of this study was to examine the role of stress across the life course in the development of depression among older adults in a non-Western developing setting.

METHODS

Multivariable linear and multinomial logistic regression were used in cross-sectional analyses of 9729 Chinese participants (mean age 60.2 years) from phase 3 of the Guangzhou Biobank Cohort Study (2006-2008) to investigate the association of childhood adversities and adulthood stressors with depression.

RESULTS

Childhood adversities were associated with mild depression (odds ratio (OR) 1.78, 95% confidence interval (CI) 1.58, 2.02) and moderate-to-severe depression (OR 2.30, 95% CI 1.68, 3.15), adjusted for age, sex, education and childhood socio-economic status. Past-year adulthood stressors were also associated with mild depression (OR 1.96, 95% CI 1.54, 2.02) and moderate-to-severe depression (OR 3.55, 95% CI 2.21, 5.68), adjusting additionally for occupation and income. Adulthood stressors were more strongly associated with depressive symptoms among individuals with a history of childhood adversities.

CONCLUSIONS

Childhood adversities and adulthood stressors were independently associated with an increased risk of depression among older ambulatory adults, although adulthood stressors were more strongly associated with depression following exposure to childhood adversities. This is consistent with evidence from Western settings in which the social context of risk and protective factors for depression may differ and implies that the role of stress in the aetiology of depression is not context specific.

Quantitative genome-wide methylation analysis of high-grade non-muscle invasive bladder cancer

High-grade non-muscle invasive bladder cancer (HG-NMIBC) is a clinically unpredictable disease with greater risks of recurrence and progression relative to their low-intermediate-grade counterparts. The molecular events, including those affecting the epigenome, that characterize this disease entity in the context of tumor development, recurrence, and progression, are incompletely understood. We therefore interrogated genome-wide DNA methylation using HumanMethylation450 BeadChip arrays in 21 primary HG-NMIBC tumors relative to normal bladder controls. Using strict inclusion-exclusion criteria we identified 1,057 hypermethylated CpGs within gene promoter-associated CpG islands, representing 256 genes. We validated the array data by bisulphite pyrosequencing and examined 25 array-identified candidate genes in an independent cohort of 30 HG-NMIBC and 18 low-intermediate-grade NMIBC. These analyses revealed significantly higher methylation frequencies in high-grade tumors relative to low-intermediate-grade tumors for the ATP5G2, IRX1 and VAX2 genes (P<0.05), and similarly significant increases in mean levels of methylation in high-grade tumors for the ATP5G2, VAX2, INSRR, PRDM14, VSX1, TFAP2b, PRRX1, and HIST1H4F genes (P<0.05). Although inappropriate promoter methylation was not invariantly associated with reduced transcript expression, a significant association was apparent for the ARHGEF4, PON3, STAT5a, and VAX2 gene transcripts (P<0.05). Herein, we present the first genome-wide DNA methylation analysis in a unique HG-NMIBC cohort, showing extensive and discrete methylation changes relative to normal bladder and low-intermediate-grade tumors. The genes we identified hold significant potential as targets for novel therapeutic intervention either alone, or in combination, with more conventional therapeutic options in the treatment of this clinically unpredictable disease.

Multiplex PCR and Next Generation Sequencing for the Non-Invasive Detection of Bladder Cancer

Background

Highly sensitive and specific urine-based tests to detect either primary or recurrent bladder cancer have proved elusive to date. Our ever increasing knowledge of the genomic aberrations in bladder cancer should enable the development of such tests based on urinary DNA.

Methods

DNA was extracted from urine cell pellets and PCR used to amplify the regions of the TERT promoter and coding regions of FGFR3, PIK3CA, TP53, HRAS, KDM6A and RXRA which are frequently mutated in bladder cancer. The PCR products were barcoded, pooled and paired-end 2 x 250 bp sequencing performed on an Illumina MiSeq. Urinary DNA was analysed from 20 non-cancer controls, 120 primary bladder cancer patients (41 pTa, 40 pT1, 39 pT2+) and 91 bladder cancer patients post-TURBT (89 cancer-free).

Results

Despite the small quantities of DNA extracted from some urine cell pellets, 96% of the samples yielded mean read depths >500. Analysing only previously reported point mutations, TERT mutations were found in 55% of patients with bladder cancer (independent of stage), FGFR3 mutations in 30% of patients with bladder cancer, PIK3CA in 14% and TP53 mutations in 12% of patients with bladder cancer. Overall, these previously reported bladder cancer mutations were detected in 86 out of 122 bladder cancer patients (70% sensitivity) and in only 3 out of 109 patients with no detectable bladder cancer (97% specificity).

Conclusion

This simple, cost-effective approach could be used for the non-invasive surveillance of patients with non-muscle-invasive bladder cancers harbouring these mutations. The method has a low DNA input requirement and can detect low levels of mutant DNA in a large excess of normal DNA. These genes represent a minimal biomarker panel to which extra markers could be added to develop a highly sensitive diagnostic test for bladder cancer.

Genetically predicted 17beta-estradiol and cardiovascular risk factors in women: a Mendelian randomization analysis using young women in Hong Kong and older women in the Guangzhou Biobank Cohort Study

PURPOSE

The role of estrogen in cardiovascular health remains contested with discrepancies between findings from randomized controlled trials and observational studies. Mendelian randomization, which assesses the effect of lifelong endogenous exposure, may help elucidate these discrepancies.

METHODS

We used separate sample instrumental variable analysis to estimate the association of log 17β-estradiol with factors related to cardiovascular disease risk (systolic and diastolic blood pressure, lipids, fasting glucose, body mass index, waist hip ratio, and waist circumference) and Framingham score, a predictor of 10-year risk of ischemic heart disease events, in older Chinese women from the Guangzhou Biobank Cohort Study (GBCS, n = 3092). The estimate was derived using the Wald estimator, that is, the ratio of the association of genetic determinants (rs1008805 and rs2175898) of log 17β-estradiol with cardiovascular disease risk factors and Framingham score in GBCS and the association of these genetic determinants with log 17β-estradiol in a sample of young women from Hong Kong (n = 236).

RESULTS

Genetically, higher 17β-estradiol was not associated with any cardiovascular disease-related risk factor or with Framingham score (-0.01, 95% confidence interval = -1.34 to 1.31).

CONCLUSIONS

Lifetime exposure to estrogen does not appear to be cardioprotective via the cardiovascular disease-related risk factors examined.

Effectiveness of additional follow-up telephone counseling in a smoking cessation clinic in Beijing and predictors of quitting among Chinese male smokers

BACKGROUND

No previous studies have investigated whether additional telephone follow-up counseling sessions after face-to-face counseling can increase quitting in China, and whether this strategy is feasible and effective for promoting smoking cessation is still unclear.

METHODS

A non-randomized controlled study was conducted in Beijing. We compared the quit rates of one group which received face-to-face counseling (FC) alone (one session of 40 min) to another group which received the same face-to-face counseling plus four follow-up sessions of brief telephone counseling (15-20 min each) at 1 week, 1, 3 and 6 month follow-up (FCF). No smoking cessation medication was provided. From October 2008 to August 2013, Chinese male smokers who sought treatment in a part-time regular smoking cessation clinic of a large general hospital in Beijing were invited to participate in the present study. Eligible male smokers (n = 547) were divided into two groups: FC (n = 149) and FCF (n = 398). Main outcomes were self-reported 7-day point prevalence and 6 month continuous quit rates at 12 month follow-up.

RESULTS

By intention to treat, at 12 month follow-up, the 7-day point prevalence and 6 month continuous quit rates of FC and FCF were 14.8 % and 26.4 %, and 10.7 % and 19.6 % respectively. The adjusted odds ratios (95 % confidence intervals) of quitting in FCF compared to FC was 2.34 (1.34-4.10) (P = 0.003) and 2.41 (1.28-4.52) (P = 0.006), respectively. Stepwise logistic regression showed that FCF, being married, unemployed and a lower Fagerström score were significant independent predictors of 6 month continuous quitting at 12 month follow-up.

CONCLUSIONS

Using systematically collected data from real-world practice, our smoking cessation clinic has shown that the additional telephone follow-up counseling sessions doubled the quit rate.

Effectiveness of varenicline and counselling for smoking cessation in an observational cohort study in China

OBJECTIVES

To evaluate the effectiveness of varenicline for smoking cessation in Chinese smokers in a real world cessation clinic practice.

DESIGN

A prospective observational study.

SETTING

Beijing, China.

PARTICIPANTS

A total of 924 smokers (883 men and 41 women) who attended a smoking cessation clinic of a large general hospital were assessed with data from structured questionnaires at baseline and follow-up at 1, 3 and 6 months. Trained physician counsellors provided free individual counselling for all subjects and follow-up interviews with brief counselling. 332 subjects additionally prescribed varenicline according to their own choice were compared with those without varenicline.

MAIN OUTCOME MEASURES

Primary outcomes were self-reported 7-day point prevalence abstinence rate and 3-month continuous abstinence rate at 6-month follow-up. Secondary outcomes were 7-day point prevalence abstinence rates at 1 and 3-month follow-up, and 1-month continuous abstinence rate at 3-month follow-up.

RESULTS

By intention-to-treat, the 7-day point prevalence abstinence rate with varenicline and counselling at 6 months was significantly higher than counselling only (37.0% vs 23.1%; OR, 1.75; 95% CI 1.46 to 2.62; p=0.001). The 3-month continuous abstinence rate at 6 months was higher with varenicline (33.1% vs 18.4%; OR, 2.04; 95% CI 1.61 to 2.99; p<0.001). Varenicline also showed better secondary outcomes.

CONCLUSIONS

Varenicline prescription in the smoking cessation clinic appeared to be effective with doubling of quit rates in Chinese smokers in a real world cessation clinic practice.

CLINICAL TRIAL REGISTRATION

NCT01935505; Results.