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Objectives: T'ai chi is a form of mind-body practice used as exercise in China, though limited data are available on characteristics of t'ai chi users and factors associated with practice. Methods: Characteristics of and factors associated with t'ai chi practice among middle-aged and elder Chinese in Shanghai China were analyzed utilizing baseline data from the Shanghai Women's Health Study and Shanghai Men's Health Study. Logistic regression modeling was used to identify independent factors associated with the practice of t'ai chi among men and women. Results: T'ai chi is the most common form of regular exercise in Shanghai China among middle-aged and elderly persons (22%), including among women (28%) and men (15%). Other popular forms of exercise were walking (7%), dancing (4%), and jogging (3%). A majority of adults who practiced t'ai chi used it as their exclusive type of exercise (69%). Overall, t'ai chi practitioners as compared to nonpractitioners were more likely women, older, more educated, retired versus still working, and more likely to report chronic medical conditions including pulmonary, gastrointestinal, and cardiovascular conditions. T'ai chi activity was associated with other health behaviors including nonsmoking, consuming ginseng, and participating in other forms of physical exercise. Conclusions: T'ai chi is the predominant form of exercise among middle-aged and elderly Chinese in urban China, particularly among those with older age and chronic medical diseases. Future research is needed to see whether t'ai chi has similar or different benefits than conventional forms of exercise such as walking and jogging. [ABSTRACT FROM AUTHOR]

Most epidemiological studies evaluating the association of fruit and vegetable intakes on lung cancer risk were conducted in North American and European countries. We investigated the association of intakes of fruits, vegetables, dietary vitamins A and C, and folate with lung cancer risk among 61,491 adult Chinese men who were recruited into the Shanghai Men's Health Study, a population-based, prospective cohort study. Baseline dietary intake was assessed through a validated food frequency questionnaire during in-home visits. Multivariate Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) of lung cancer risk associated with dietary intakes. During a median follow-up of 5.5 yr, 359 incident lung cancer cases accrued after the first year of follow-up and 68.8% of them were current smokers. Intakes of green leafy vegetables, β-carotene-rich vegetables, watermelon, vitamin A, and carotenoids were inversely associated with lung cancer risk; the corresponding HR (95% CI) comparing the highest with the lowest quartiles were 0.72 (0.53–0.98), 0.69 (0.51–0.94), 0.65 (0.47–0.90), 0.63 (0.44–0.88), and 0.64 (0.46–0.88). Intake of all fruits and vegetables combined was marginally associated with lower risk. Our study suggests that the consumption of carotenoid-rich vegetables is inversely associated with lung cancer risk. [ABSTRACT FROM PUBLISHER]

Little is known about the association of circulating 25-hydroxyvitamin D (25(OH)D) and blood pressure (BP) parameters, including systolic and diastolic BP, pulse pressure (PP), mean arterial pressure (MAP) and hypertension in non-Western populations that have not yet been exposed to foods fortified with vitamins and seldom use vitamin D supplements. A cross-sectional analysis of plasma 25(OH)D levels in association with BP measures was performed for 1460 participants (1055 women and 405 men, aged 40–74 years) of two large cohort studies in Shanghai. Multivariable linear and logistic regressions were conducted. Overall, the prevalence of vitamin D deficiency was 55·8 % using National Health and Nutrition Examination Survey, USA criteria and 29·9 % using WHO criteria. The median plasma 25(OH)D level in the population was 38·0 nmol/l for men and 33·6 nmol/l for women (P < 0·01) among participants who were not on antihypertensive drugs. Among men, BP parameters (systolic BP, diastolic BP and MAP) were significantly and inversely associated with higher quintiles of 25(OH)D compared with the lowest quintile (Ptrend < 0·05 for all). Vitamin D non-deficient status (WHO criteria) was inversely associated with hypertension (ORadjusted = 0·29; 95 % CI 0·10, 0·82). An inverse association was also found between hypertension and the highest quintile of 25(OH)D (ORadjusted = 0·16; 95 % CI 0·04, 0·65 for ≥ 50·6 nmol/l; Ptrend = 0·02). Among women, no significant associations were found for BP parameters and hypertension. The present study shows that vitamin D deficiency is common among adults in urban China. Circulating 25(OH)D levels were inversely related to the levels of individual BP parameters and hypertension among middle-aged and elderly men but not among women. More research is needed to investigate the potential sex differential associations. [ABSTRACT FROM PUBLISHER]

The effects of diet on breast cancer are controversial and whether the effects vary with hormone receptor status has not been well investigated. This study evaluated the associations of dietary factors with risk for breast cancer overall and by the hormone receptor status of tumors among Chinese women. The Shanghai Breast Cancer Study, a large, population-based, case-control study, enrolled 3,443 cases and 3,474 controls in 1996–1998 (phase I) and 2002–2005 (phase II); 2676 cases had estrogen receptor (ER) and progesterone receptor (PR) data. Dietary intake was assessed using a validated, quantitative, food frequency questionnaire. Odds ratios (OR) and 95% confidence intervals (95% CI) were derived from multivariate, polychotomous, unconditional logistic regression models. Total vegetable intake was inversely related to breast cancer risk, with an adjusted OR for the highest quintile of 0.80 (95% CI = 0.67–0.95; P trend = 0.02). Reduced risk was also related to high intake of allium vegetables (P trend = 0.01) and fresh legumes (P trend = 0.0008). High intake of citrus fruits and rosaceae fruits were inversely associated with breast cancer risk (P trend = 0.003 and 0.004, respectively), although no consistent association was seen for total fruit intake. Elevated risk was observed for all types of meat and fish intake (all P trend < 0.05), whereas intakes of eggs and milk were associated with a decreased risk of breast cancer (both P trend <0.05). There was little evidence that associations with dietary intakes varied across the 4 tumor subtypes or between ER+/PR+ and ER-/PR- tumors (P for heterogeneity >0.05). Our results suggest that high intake of total vegetables, certain fruits, milk, and eggs may reduce the risk of breast cancer, whereas high consumption of animal-source foods may increase risk. The dietary associations did not appear to vary by ER/PR status. [ABSTRACT FROM PUBLISHER]

Obesity is a well-established risk factor for endometrial cancer, the most common gynecologic malignancy. Recent genome-wide association studies (GWAS) have identified multiple genetic markers for obesity. The authors evaluated the association of obesity-related single nucleotide polymorphisms (SNPs) with endometrial cancer using GWAS data from their recently completed study, the Shanghai Endometrial Cancer Genetics Study, which comprised 832 endometrial cancer cases and 2,049 controls (1996–2005). Thirty-five SNPs previously associated with obesity or body mass index (BMI; weight (kg)/height (m)2) at a minimum significance level of ≤5 × 10−7 in the US National Human Genome Research Institute's GWAS catalog (http://genome.gov/gwastudies) and representing 26 unique loci were evaluated by either direct genotyping or imputation. The authors found that for 22 of the 26 unique loci tested (84.6%), the BMI-associated risk variants were present at a higher frequency in cases than in population controls (P = 0.0003). Multiple regression analysis showed that 9 of 35 BMI-associated variants, representing 7 loci, were significantly associated (P ≤ 0.05) with the risk of endometrial cancer; for all but 1 SNP, the direction of association was consistent with that found for BMI. For consistent SNPs, the allelic odds ratios ranged from 1.15 to 1.29. These 7 loci are in the SEC16B/RASAL, TMEM18, MSRA, SOX6, MTCH2, FTO, and MC4R genes. The associations persisted after adjustment for BMI, suggesting that genetic markers of obesity provide value in addition to BMI in predicting endometrial cancer risk. [ABSTRACT FROM PUBLISHER]

Etiologic differences between subtypes of breast cancer defined by estrogen receptor (ER) and progesterone receptor (PR) status are not well understood. The authors evaluated associations of hormone-related factors with breast cancer subtypes in a population-based case-control study involving 1,409 ER-positive (ER+)/PR-positive (PR+) cases, 712 ER-negative (ER−)/PR-negative (PR−) cases, 301 ER+/PR− cases, 254 ER−/PR+ cases, and 3,474 controls aged 20–70 years in Shanghai, China (phase I, 1996–1998; phase II, 2002–2005). Polytomous logistic regression and Wald tests for heterogeneity across subtypes were conducted. Breast cancer risks associated with age at menarche, age at menopause, breastfeeding, age at first livebirth, waist-to-hip ratio, and oral contraceptive use did not differ by hormone receptor status. Among postmenopausal women, higher parity (≥2 children vs. 1) was associated with reduced risk (odds ratio (OR) = 0.69, 95% confidence interval (CI): 0.52, 0.91) and higher body mass index (BMI; weight (kg)/height (m)2) with increased risk (highest quartile: OR = 2.40, 95% CI: 1.65, 3.47) of the ER+/PR+ subtype but was unrelated to the ER−/PR− subtype (for parity, Pheterogeneity = 0.02; for BMI, Pheterogeneity < 0.01). Hormone replacement therapy (OR = 2.25, 95% CI: 1.40, 3.62) and alcohol consumption (OR = 1.59, 95% CI: 1.01, 2.51) appeared to be preferentially associated with the ER+/PR− subtype. These findings indicate that BMI, parity, hormone replacement therapy, and alcohol consumption may play different roles in subtypes of breast cancer. More research is needed to better understand the etiology of 2 relatively rare subtypes, ER+/PR− tumors and ER−/PR+ tumors. [ABSTRACT FROM PUBLISHER]

Although genetic variations in cell-cycle control genes have been previously linked to cancer risk, no study has specifically evaluated the role of these gene variants in endometrial carcinogenesis. Using data from the Shanghai Endometrial Cancer Study, a population-based case-control study with 1,199 cases and 1,212 age-matched controls (1997–2003), the authors carried out a systematic evaluation of the association of cell-cycle control genes with endometrial cancer risk. Sixty-five tagging or potentially functional single nucleotide polymorphisms in the CCNB1, CCND1, CCNE1, CDK2, CDK4, CDK6, CDKN1A, CDKN1B, and CDKN2A genes were genotyped and evaluated. Three single nucleotide polymorphisms in the CDKN1B gene (rs11055027, rs3759216, and rs34330) were related to endometrial cancer risk, although only the association with rs34330 remained statistically significant after adjustment for multiple comparisons. The odds ratios for rs34330 were 1.33 (95% confidence interval (CI): 1.06, 1.66) and 1.51 (95% CI: 1.16, 1.94) for the CT and TT genotypes, respectively, compared with the CC genotype. In vitro luciferase reporter assays showed that the minor allele (A) in rs3759216, which was associated with decreased endometrial cancer risk (odds ratio = 0.73, 95% CI: 0.56, 0.94) without adjustment for multiple comparisons, significantly increased promoter activity. These findings suggest that polymorphisms of the CDKN1B gene may play a role in endometrial carcinogenesis. [ABSTRACT FROM PUBLISHER]