Cross-sectional study of household solid fuel use and renal function in older adults in China.

BACKGROUND: Emerging evidence links outdoor air pollution and declined renal function but the relationship between household air pollution and renal function is not well understood. METHODS: Using cross-sectional data from the multi-provincial INTERMAP-China Prospective Study, we collected blood samples and questionnaire information on stove use and socio-demographic factors. We calculated estimated glomerular filtration rate (eGFR) from serum creatinine to assess renal function. Participants with eGFR <60 mL/min per 1.73 m2 were defined as having chronic kidney disease (CKD) in this analysis. Generalized estimating equations were used to estimate the association of household fuel with renal function and prevalent CKD in models adjusting for confounders. RESULTS: Among the 646 enrolled adults (40-79y; 56% female), one-third exclusively used clean fuel (gas and electric) cookstoves and 11% of northern China participants (n = 49 of 434) used only clean fuel heaters, whereas the rest used solid fuel. In multivariable models, use of solid fuel cookstoves was associated with 0.17 ml/min/1.73 m2 (95% CI: -0.30, 0.64) higher eGFR and 19% (0.86, 1.64) higher prevalence of CKD than exclusive clean fuel use. Greater intensity of solid fuel use was associated with 0.25 ml/min/1.73 m2 (-0.71, 0.21) lower eGFR per 5 stove-use years, though the confidence intervals included the null, while greater current intensity of indoor solid fuel use was associated with 1.02 (1.00, 1.04) higher prevalent CKD per 100 stove-use days per year. Larger associations between current solid fuel use and intensity of use with lower eGFR and prevalent CKD were observed among participants in southern China, those with hypertension or diabetes (eGFR only), and females (CKD only), through these groups had small sample sizes and some confidence intervals included the null. CONCLUSION: We found inconsistent evidence associating household solid fuel use and renal function in this cross-sectional study of peri-urban Chinese adults.

Physical activity level and incident type 2 diabetes among Chinese adults.

PURPOSE: The objective is to examine the association between physical activity level (PAL) and incident type 2 diabetes among middle-age and older Chinese men and women in urban China. METHODS: This prospective study included 6348 participants (age 35 to 74 yr) who were free of diabetes and cardiovascular disease at baseline. PAL was estimated on the basis of self-reported overall physical activity on a typical day. According to PAL, participants were classified into four groups: sedentary (PAL, 1.00-1.39), low active (PAL, 1.40-1.59), active (PAL, 1.60-1.89), and very active (PAL, >1.89). The association of PAL with incident diabetes was examined by Cox proportional hazards model. RESULTS: During 7.9 yr of follow-up (50,293 person-years), 478 incident cases of type 2 diabetes were identified. After adjustment for age, sex, geographic region, educational level, smoking, alcohol use, and family history of diabetes, the HR (95% CI) values for type 2 diabetes across increasing categories of PAL were 1.00 (reference), 0.82 (0.62-1.09), 0.63 (0.47-0.83), and 0.47 (0.36-0.61), respectively (P for trend <0.0001). Additional adjustment for baseline body mass index or waist circumference attenuated the magnitude of risk reduction, but it remained significant. The inverse association between PAL and risk of incident diabetes was persistent in subgroup analyses according to age, sex, hypertension, smoking, body mass index, waist circumference, and fasting plasma glucose level. CONCLUSIONS: Higher PAL is associated with substantial reduction in risk of type 2 diabetes. Our findings suggest the importance of a physically active lifestyle in the prevention of diabetes.

[Relationship between physical activity and the incidence of metabolic syndrome in Chinese adults: a prospective cohort study].

OBJECTIVE: To investigate the association between physical activity (PA) and the incidence of metabolic syndrome (MS) in Chinese adults. METHODS: Data on PA and other variables were obtained at the baseline examination of China Multi-center study of Cardiovascular Epidemiology in 1998 and of International Collaborative study of Cardiovascular Disease in Asia(InterASIA) during 2000 - 2001. Follow-up study was conducted in 2007 - 2008. A total of 11 512 Chinese adults aged 35 - 74 years (5563 men and 5949 women) were included in the final data analysis. Information on demographics, PA, smoking and alcohol consumption were obtained and components of MS were examined. Participants were divided into four groups according to quartile of total metabolic equivalent (MET) values per day. In addition, subjects were grouped into the following categories according to occupational PA: inactive, light, moderate and vigorous. Binary logistic model was used to examine the association between PA and the incidence of MS. RESULTS: A total of 2527 cases with MS were documented during an average following up of 8.1 years. The annual incidence rate of MS was 2.71% (2527/93 178.68). After multivariate logistic regression analysis, compared with participants with total PA volume < 32.0 MET×h×d(-1) (annual incidence rate was 3.19% (697/21 830.74)), the RR (95%CI) value of participants with total PA volume during 32.00 - 37.85, 37.86 - 52.29, and ≥ 52.30 MET×h×d(-1) was 1.05(0.92 - 1.19), 0.98(0.86 - 1.12), and 0.68(0.59 - 0.80), respectively (χ(2)trend = 34.23, P < 0.05), with corresponding annual incidence rates of 2.82% (690/24 504.25), 2.73% (661/24 179.36) and 2.11% (479/22 664.33). In addition, compared to inactive occupational PA (annual incidence rate was 2.76% (402/14 588.33)), the corresponding RR (95%CI) value was 0.80 (0.69 - 0.92), 0.70 (0.59 - 0.82), and 0.54 (0.45 - 0.65) (χ(2)trend = 42.34, P < 0.05), and the annual incidence rates were 2.86% (648/22 663.41), 2.40% (455/18 956.14) and 1.89% (344/18 173.86) in participants with light, moderate and vigorous occupational PA, respectively. CONCLUSION: Both increased total PA volume and occupational PA intensity are significantly associated with decreased risk of incidence of MS.

Genome-wide association study in Han Chinese identifies four new susceptibility loci for coronary artery disease.

We performed a meta-analysis of 2 genome-wide association studies of coronary artery disease comprising 1,515 cases and 5,019 controls followed by replication studies in 15,460 cases and 11,472 controls, all of Chinese Han ancestry. We identify four new loci for coronary artery disease that reached the threshold of genome-wide significance (P < 5 × 10(-8)). These loci mapped in or near TTC32-WDR35, GUCY1A3, C6orf10-BTNL2 and ATP2B1. We also replicated four loci previously identified in European populations (in or near PHACTR1, TCF21, CDKN2A-CDKN2B and C12orf51). These findings provide new insights into pathways contributing to the susceptibility for coronary artery disease in the Chinese Han population.