Xiulou Li

Cohort Profile: The Dongfeng–Tongji cohort study of retired workers

China has seen rapid socio-economic and epidemiolo-gical changes over the past several decades. Economicgrowth plus shifts in environment, lifestyles and diethave increased life expectancy, but they have also ledto a higher burden of chronic, non-communicablediseases. Stroke, coronary heart disease (CHD), cancerand diabetes account for 80% of the deaths and 70%of the disability-adjusted life-years lost in China.

Different Physical Activity Subtypes and Risk of Metabolic Syndrome in Middle-Aged and Older Chinese People

Background The prevalence of metabolic syndrome (MetS) is growing rapidly in China. Tai chi and dancing are common types of exercise among middle-aged and elderly Chinese. It remains unclear whether these activities are associated with a lower risk of MetS. Methodology/Principal Findings A total of 15,514 individuals (6,952 men, 8,562 women) aged 50 to 70 years from the Dongfeng-Tongji Cohort in Shiyan, China participated in a cross-sectional study. Physical activity and other lifestyle factors were assessed with semi-structured questionnaires during face-to-face interviews. MetS was defined by the current National Cholesterol Education Program/Adult treatment Panel III criteria for Asian Americans. The prevalence of MetS was 33.2% in the study population. In the multivariable-adjusted logistic regression analyses, total physical activity levels were monotonically associated with a lower odds of MetS [OR 0.75 comparing extreme quintiles, 95% confidence interval (CI) 0.66–0.86, P<0.001]. Compared with non-exercisers in a specific exercise type, jogging (OR 0.82, 95% CI 0.68–1.00, P = 0.046), tai chi (OR 0.72, 95% CI 0.60–0.88, P<0.001), and dancing (OR 0.56, 95% CI 0.47–0.67, P<0.001) were associated with significantly lower odds of MetS. Furthermore, each 1–h/week increment in tai chi and dancing was associated with a 5% (95% CI 2%–9%) and a 9% (95% CI 6%, 12%) lower risk of MetS. Conclusions/Significance Jogging, tai chi and dancing are associated with a significantly lower risk of having MetS in middle-aged and older Chinese. Future intervention studies should consider the role of jogging, tai chi and dancing in preventing MetS.

Longer Sleep Duration and Midday Napping Are Associated with a Higher Risk of CHD Incidence in Middle-Aged and Older Chinese: the Dongfeng-Tongji Cohort Study.

STUDY OBJECTIVES To analyze the independent and combined relations of sleep duration and midday napping with coronary heart diseases (CHD) incidence along with the underlying changes of cardiovascular disease (CVD) risk factors among Chinese adults. METHODS We included 19,370 individuals aged 62.8 years at baseline from September 2008 to June 2010, and they were followed until October 2013. Cox proportional hazards models and general linear models were used for multivariate longitudinal analyses. RESULTS Compared with sleeping 7- < 8 h/night, the hazard ratio (HR) of CHD incidence was 1.33 (95% CI = 1.10 to 1.62) for sleeping ≥ 10 h/night. The association was particularly evident among individuals who were normal weight and without diabetes. Similarly, the HR of incident CHD was 1.25 (95% CI = 1.05 to 1.49) for midday napping > 90 min compared with 1-30 min. When sleep duration and midday napping were combined, individuals having sleep duration ≥ 10 h and midday napping > 90 min were at a greater risk of CHD than those with sleeping 7- < 8 h and napping 1-30 min: the HR was 1.67 (95% CI = 1.04 to 2.66; P for trend = 0.017). In addition, longer sleep duration ≥ 10 h was significantly associated with increases in triglycerides and waist circumference, and a reduction in HDL-cholesterol; while longer midday napping > 90 min was related to increased waist circumference. CONCLUSIONS Both longer sleep duration and midday napping were independently and jointly associated with a higher risk of CHD incidence, and altered lipid profile and waist circumference may partially explain the relationships.

Green tea consumption is associated with reduced incident CHD and improved CHD-related biomarkers in the Dongfeng-Tongji cohort.

Prospective studies on the association of green tea with risk of coronary heart disease (CHD) incidence were scarce. This study examined whether green tea can reduce CHD incidence and have a beneficial effect on CHD-related risk markers in middle-aged and older Chinese population. We included 19 471 participants who were free of CHD, stroke or cancer at baseline from September 2008 to June 2010, and were followed until October 2013. Cox proportional hazard models were used to examine the hazard ratios (HR) of CHD incidence in relation to green tea consumption. Linear regression models were used to evaluate the effect of green tea on 5-year changes of CHD-related biomarkers. Compared with non-green tea consumers, the multivariable-adjusted HR for CHD was 0.89 (95% CI, 0.81-0.98) in green tea consumers. Particularly, the reduced risk of CHD incidence with green tea consumption was more evident among participants who were male, more than 60 years old, overweight, or with diabetes mellitus. In addition, green tea consumption improved multiple CHD-related risk markers including total cholesterol, HDL-cholesterol, triglycerides, mean platelet volume, and uric acid. In conclusion, green tea consumption was associated with a reduced risk of CHD incidence in the middle-aged and older Chinese populations, and the association might be partly due to altered CHD-related biomarkers.

Higher Carbohydrate Antigen 125 Levels Are Associated with Increased Risk of Coronary Heart Disease in Elderly Chinese: A Population-Based Case-Control Study

Background High carbohydrate antigen 125 (CA-125) level was reported to be associated with some cardiac dysfunctions, such as chronic heart failure, but the relationship between CA-125 level and coronary heart disease (CHD) risk remains unclear. The aim of this study was to explore the potential association in a Chinese older population. Methods In a population-based case-control study conducted in a Chinese older population, serum CA-125 levels were measured in 1177 diagnosed CHD patients and 3531 age and sex matched control subjects without CHD. Results Serum CA-125 level was significantly higher in CHD patients than controls (P < 0.001) with adjustment for age, gender, smoking, drinking, BMI, physical activity, hypertension, dyslipidemia, diabetes mellitus, medication history and family history of CHD and myocardial infarction. CHD risk was doubled (OR: 2.10, 95%CI: 1.69-2.60) among subjects in the highest quartile compared to those in the lowest quartile of CA-125 level (P trend < 0.001). Furthermore, CA-125 levels were associated with CHD risks in subjects with age over 60 years (OR: 2.19, 95%CI: 1.75-2.73), current smokers (OR: 2.29, 95%CI: 1.50-3.49), current drinkers (OR: 2.35, 95%CI: 1.57-3.53) and subjects with hypertension (OR: 2.04, 95%CI: 1.71-2.43). Conclusions Elevated serum CA-125 level might be associated with increased risk of coronary heart disease in the Chinese older population. Further investigations are needed to identify the possible biological role of CA-125 in CHD development in the future.

Helicobacter pylori infection is associated with type 2 diabetes among a middle‐ and old‐age Chinese population

Although the association of Helicobacter pylori (H. pylori) infection with diabetes mellitus has been evaluated, findings are controversial. This study investigated the association in a Chinese population.

Long sleep duration and afternoon napping are associated with higher risk of incident diabetes in middle-aged and older Chinese: the Dongfeng-Tongji cohort study.

Abstract Background In this study, we investigated the independent and combined effects of sleep duration and afternoon napping on the risk of incident diabetes among a cohort of middle-aged and older Chinese adults. Methods Information of sleep and napping was obtained by questionnaires during face-to-face interviews. We categorized sleep duration into <7 h, 7∼<8 h (reference), 8∼<9 h, 9∼<10 h, and ≥ 10 h. Afternoon napping was divided into no napping (0 min) (reference), 1–30 min, 31–60 min, 61–90 min, and > 90 min. Cox proportional hazard regression models were used. Results Compared with referential sleeping group, subjects sleeping ≥10 h had a 42% higher risk of developing diabetes. The HR was 1.28 for napping > 90 min when compared with no napping. These associations were more pronounced in individuals without hypertension. Combined effects of long sleep duration and afternoon napping were further identified. Individuals with both sleep duration ≥ 10 h and napping > 60 min had a 72% higher risk of incident diabetes than those with sleeping 7∼<8 h and napping 0 min (all above p < 0.05). Conclusions Both long sleep duration and afternoon napping were independently and jointly associated with higher risk of incident diabetes. Key messages Sleep duration was associated with diabetes, but whether it is a real cause of incident diabetes especially in Chinese still remains to be elucidated. The association of afternoon napping and diabetes was not consistent and definite, we clarified this association in a large prospective study. Long sleep duration and afternoon napping were independently and jointly associated with higher risk of incident diabetes.

Association between serum bilirubin levels and decline in estimated glomerular filtration rate among patients with type 2 diabetes.

AIMS Studies indicate that elevated serum total bilirubin (TBil) levels are associated with lower risk of diabetic kidney disease (DKD). Few studies examined the associations of direct bilirubin (DBil) and indirect bilirubin (IBil) with the development of DKD. METHODS Type 2 diabetes patients (n=2,958) with estimated glomerular filtration (eGFR)≥60mlmin(-1) 1.73m(-2) from the Dongfeng-Tongji cohort were selected and followed up for 5years. Development of DKD was defined as decline in eGFR≥30% during follow-up. Generalize linear model was used to assess the associations of bilirubin levels with DKD development. RESULTS Compared with those in the first tertile of serum TBil, the relative risks (RRs) and 95% confidence intervals (CIs) of incident eGFR decline for tertile 2 to 3 were 0.83 (0.64-1.09) and 0.74 (0.56-0.98), Ptrend=0.04. The counterpart RRs (95% CIs) in IBil were 0.74 (0.57-0.97) and 0.75 (0.57-0.98), Ptrend=0.04. No significant associations were observed in DBil. Moreover, TBil and IBil interacted with smoking, the bilirubin-DKD associations were evident in ever smokers. CONCLUSIONS Our findings suggest that elevation of serum TBil or IBil levels are independent protective factors for development of DKD, particularly in smokers.

Dose-response relationship between serum uric acid levels and risk of incident coronary heart disease in the Dongfeng-Tongji Cohort

BACKGROUND In prospective studies, relationship of serum uric acid (SUA) with risk of coronary heart disease (CHD) incidence is inconsistent. We evaluated the association of SUA with incident CHD and the potential modifying effect of major CHD risk factors related to SUA among a middle aged and elderly Chinese population. METHODS We included 16, 063 participants who were free of CHD, stroke, cancer and renal diseases at baseline from Sep. 2008 to June 2010, and were followed until Oct. 2013. Cox proportional hazard model was used to estimate the hazard ratios (HR) and 95% confidence interval (95% CI) of CHD incidence in relation to SUA. RESULTS The adjusted HR for incident CHD increased gradually with the increasing SUA levels (P for linear trend=0.005), and the HR across sex-specific SUA quartile was 1.26 (95% CI: 1.09, 1.47), 1.13 (95% CI: 0.97, 1.31), 1.23 (95% CI: 1.06, 1.43) and 1.00 (reference; P for trend=0.014), respectively. In particular, the association was more evident in individuals with normal-weight and those without hypertension or metabolic syndrome (all P for interactions<0. 05). CONCLUSIONS These findings suggested that higher SUA levels were independently associated with a dose-response increased risk of CHD incidence.

TH-C-BRB-01: Toward a thorough Evaluation of IMPT Plan Sensitivity to Uncertainties: Revisit the Worst-Case Analysis with An Exhaustively Sampling Approach

Purpose: Intensity‐modulated proton therapy (IMPT) has a great potential to further advance proton therapy. However, it is widely accepted that IMPT is very sensitive to uncertainties. The worst‐case analysis (WA) originally proposed by Lomax has been adopted in our institute to evaluate IMPT plan sensitivity to range and setup uncertainties. Here, we propose an evaluation method by exhaustively sampling uncertainties and apply it to validate WA. Methods: A series of perturbations to modify proton beam ranges and to shift the iso‐center in x‐, y‐ and z‐directions were sampled for 500 times to generate the probability distribution of plan qualities. The magnitude of a perturbation was assigned randomly following a normal distribution with specified standard deviations in each perturbation dimension. Perturbed dose was calculated for each sampling and compared to the WA dose. Dose‐volume‐histograms (DVH) were obtained for all perturbed doses. The distribution of DVHs and dose‐volume indices were examined. Prostate and head/neck cases were selected for demonstration. Results: In both cases, the DVHs of 500 perturbed doses spread over bands with various widths, and the DVH curves of WA lie within these bands and near the “worst” edges. for CTV, 97.6% in the prostate case and 97% in the head/neck case of the perturbed doses show a D95 value higher than the value given by WA. For normal tissues, at least 96.4% of the perturbed doses show lower dose‐volume indices (e.g. V70 of rectum and bladder) than the ones by WA. Conclusions: After exhaustively sampling the possible uncertainties, we verified that the worst‐case analysis may reasonably evaluate the IMPT plan sensitivity to setup and range uncertainties without considerably over‐ or under‐estimating it. The exhaustively sampling approach proposed here could offer a great outset toward comprehensively evaluating the IMPT plan sensitivity to a broader spectrum of planning and delivery uncertainties.