Correlates of 25-hydroxyvitamin D among Chinese breast cancer patients.

BACKGROUND: Few studies have investigated vitamin D status in association with modifiable lifestyle factors and clinical characteristics among breast cancer patients, with no studies among Chinese women, who may be at higher risk of vitamin D deficiency. We aimed to evaluate circulating 25-hydroxyvitamin D (25(OH)D) levels in association with clinical and lifestyle factors among 1,940 Chinese breast cancer patients. METHODS: Participants included breast cancer cases aged 22-77 from a population-based case-control study conducted in Shanghai, China during 1996-1998 (n = 1,044) and 2002-2005 (n = 896). Circulating 25(OH)D levels were measured in plasma samples (95% collected ≤6 months post-diagnosis). Prevalence ORs and 95% CIs were derived from multinomial logistic regression models, adjusting for age, season, and other factors. RESULTS: About 23% and 48% of women were vitamin D deficient (<30 nmol/L) or insufficient (30-50 nmol/L), respectively. Tumor characteristics were not associated with vitamin D status. Higher BMI was associated with increased odds of vitamin D deficiency (ORs (95% CIs): 1 (reference), 1.12 (0.85,1.47), and 1.57 (1.02,2.42), for <23, 23-<27.5, and ≥27.5 kg/m(2), respectively, Ptrend <0.06). Total physical activity was associated with reduced odds of vitamin D deficiency (ORs (95% CIs):1 (reference), 0.84 (0.59,1.20), 0.65 (0.45,0.93), and 0.69 (0.48,1.00), for <7.65, 7.65-<10.6, 10.6-<13.5, ≥13.5 MET-hours/day, respectively, Ptrend <0.02). Smoking was associated with vitamin D insufficiency and deficiency (ORs (95% CIs): 2.50 (1.07,5.84) and 2.78 (1.11,6.95), respectively). CONCLUSIONS: In the largest study to date, the prevalence of low vitamin D status was high among Chinese breast cancer patients and associated with higher BMI, smoking, and lower physical activity. Our findings support careful monitoring of vitamin D status and recommendations for supplementation and other lifestyle modifications that may improve vitamin D status in breast cancer patients.

Menopausal symptoms among breast cancer patients: a potential indicator of favorable prognosis.

Menopausal symptoms have been suggested to be an indicator of better prognosis among patients treated for breast cancer, because women who experience these symptoms usually have a lower level of estrogen. We tested this hypothesis in a population-based, prospective cohort study involving 4,842 women with stage 0 to III primary breast cancer who were enrolled in the Shanghai Breast Cancer Survival Study between March 2002 and April 2006, were aged 20 to 75 years, and were recruited 6 months post-diagnosis. They were followed-up by in-person surveys and record linkages with the vital statistics registry. Cox regression analysis was used to evaluate the association of menopausal symptoms at baseline with breast cancer recurrence. Approximately 56% of patients experienced at least one menopausal symptom, including hot flashes, night sweats, and/or vaginal dryness at baseline. During a median follow-up period of 5.3 years, 720 women had a recurrence. Experiencing hot flashes or having ≥2 menopausal symptoms was associated with lower risk of recurrence among premenopausal women (hazard ratio [HR]=0.77, 95% confidence interval [CI]: 0.62-0.96 for hot flashes; 0.73, 0.56-0.96 for ≥2 menopausal symptoms). Lower recurrence risk in relation to hot flashes was also observed among women who were not overweight/obese (HR=0.78, 95% CI: 0.64-0.99), those with relatively low waist-to-hip ratio (WHR) (HR=0.77, 95% CI: 0.61-0.97), and those who used tamoxifen (HR=0.75, 95% CI: 0.58-0.98). Consistently experiencing multiple menopausal symptoms was associated with lower recurrence risk among women with low WHR or who used tamoxifen. This large, population-based cohort study of women with breast cancer confirms that experiencing menopausal symptoms is an indicator of favorable breast cancer prognosis.

No association between genetic variants in angiogenesis and inflammation pathway genes and breast cancer survival among Chinese women.

BACKGROUND: Angiogenesis and inflammation are implicated in breast cancer prognosis; however, the role of individual germline variation in related genes is unknown. METHODS: A two-stage candidate pathway association study was conducted among 6983 Chinese women. Stage 1 included 2884 women followed for a median of 5.7 years; Stage 2 included 4099 women followed for a median of 4.0 years. Cox proportional hazards regression was used to estimate the effects of genetic variants on disease-free survival (DFS) and overall survival (OS). RESULTS: Stage 1 included genotyping of 506 variants in 22 genes; analysis was conducted for 370 common variants. Nominally significant associations with DFS and/or OS were found for 20 loci in ten genes in Stage 1; variants in 19 loci were successfully genotyped and evaluated in Stage 2. In analyses of both study stages combined, nominally significant associations were found for nine variants in seven genes; none of these associations surpassed a significance threshold level corrected for the total number of variants evaluated in this study. CONCLUSIONS: No association with survival was found for 370 common variants in 22 angiogenesis and inflammation pathway genes among Chinese women with breast cancer. IMPACT: Our data do not support a large role for common genetic variation in 22 genes in breast cancer prognosis; research on angiogenesis and inflammation genes should focus on common variation in other genes, rare host variants, or tumor alterations.

Association of genetic markers in the BCL-2 family of apoptosis-related genes with endometrial cancer risk in a Chinese population.

BACKGROUND: In vitro studies have demonstrated the role of the BCL-2 family of genes in endometrial carcinogenesis. The role of genetic variants in BCL-2 genes and their interactions with non-genetic factors in the development of endometrial cancer has not been investigated in epidemiological studies. PATIENTS AND METHODS: We examined the relationship between BCL-2 gene family variants and endometrial cancer risk among 1,028 patients and 1,922 age-matched community controls from Shanghai, China. We also investigated possible interactions between genetic variants and established risk factors (demographic, lifestyle and clinical). Individuals were genotyped for 86 tagging single nucleotide polymorphisms (SNPs) in the BCL2, BAX, BAD and BAK1 genes. RESULTS: Significant associations with endometrial cancer risk were found for 9 SNPs in the BCL2 gene (P trend<0.05 for all). For SNPs rs17759659 and rs7243091 (minor allele for both: G), the associations were independent. The odds ratio was 1.27 (95% CI: 1.04-1.53) for women with AG genotype for the SNP rs17759659 and 1.82 (95% CI: 1.21-2.73) for women with the GG genotype for the SNP rs7243091. No interaction between these two SNPs and established non-genetic risk factors of endometrial cancer was noticed. CONCLUSION: Genetic polymorphisms in the BCL2 gene may be associated with the risk of endometrial cancer in Chinese women.

Sibling composition and children's anthropometric indicators of nutritional status: evidence from native Amazonians in Bolivia.

BACKGROUND: Siblings compete for parental resources. Little is known about how sibling composition (older sisters, older brothers, younger sisters, younger brothers) might affect child anthropometric indicators of nutritional status. AIM: This study evaluates the associations between sibling composition and child anthropometry using panel data from a native Amazonian society (Tsimane'). METHODS: Anthropometry of ~168 girls and 169 boys aged 2-9 years were measured annually during 2002-2007 (2360 observations). Children's weight-for-height Z-score (WHZ), mid-upper arm circumference (MUAC), mid-upper arm muscle area (AMA) and triceps skin-fold thickness (TST) were regressed separately against all of the sibling composition variables while controlling for child's age and survey year. Multivariate panel linear regressions were used with individual, village, survey year and village-year fixed-effects, clustering by household. RESULTS: Among girls, an additional older brother was associated with a 1.4% decrease in MUAC (p < 0.01) and a 4.3% decrease in AMA (p < 0.01); an additional younger sister was associated with a 6.3% decrease in TST (p < 0.01). The association between sibling composition and arm anthropometry was robust to various model specifications. CONCLUSION: Older brothers and younger sisters were negatively associated with arm measures in girls. This finding may help improve policy interventions that aim to address children's nutritional health and long-term well-being.

Major metabolite of F2-isoprostane in urine may be a more sensitive biomarker of oxidative stress than isoprostane itself.

BACKGROUND: There is limited literature on the contributors to isoprostane metabolite 2,3-dinor-5,6-dihydro-15-F(2t)-isoprostane (15-F(2t)-IsoP-M) compared with F(2)-isoprostanes (F(2)-IsoPs) as an oxidative stress biomarker. OBJECTIVE: The objective of this study was to investigate whether plasma concentrations of antioxidants, urinary excretion rates of polyphenols, and antioxidants in food and dietary supplements are attributable to both urinary F(2)-IsoP and 15-F(2t)-IsoP-M concentrations. DESIGN: Dietary intake information and blood and urine samples were obtained from 845 healthy middle-aged and elderly female participants of the Shanghai Women's Health Study. Urinary isoprostanes (F(2)-IsoPs and 15-F(2t)-IsoP-M) were measured and adjusted for creatinine concentrations. RESULTS: Urinary 15-F(2t)-IsoP-M and F(2)-IsoP concentrations were lower in subjects who used a multivitamin. Lower F(2)-IsoP concentrations were observed in ginseng users, whereas lower concentrations of 15-F(2t)-IsoP-M were shown in subjects who used a vitamin E supplement. Plasma concentrations of several antioxidants (ie, ß-carotenes, both trans and cis ß-carotenes, lycopene other than trans, 5-cis and 7-cis isomers, cis anhydrolutein, and cis ß-cryptoxanthin) were inversely associated with 15-F(2t)-IsoP-M but not with F(2)-IsoPs, whereas ß-, γ-, and δ-tocopherols were positively associated with 15-F(2t)-IsoP-M but not with F(2)-IsoPs. Urinary polyphenol quercetin was positively associated with both F(2)-IsoPs and 15-F(2t)-IsoP-M. CONCLUSION: The results suggest that the F(2)-IsoP major metabolite 15-F(2t)-IsoP-M may be a more sensitive marker of endogenous oxidative stress status than are F(2)-IsoPs in the assessment of effects of antioxidants on age-related diseases.

Circulating 25-hydroxyvitamin D levels in relation to blood pressure parameters and hypertension in the Shanghai Women's and Men's Health Studies.

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 (P trend < 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; P trend = 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.

Common genetic variants in the vitamin D pathway including genome-wide associated variants are not associated with breast cancer risk among Chinese women.

BACKGROUND: Previous studies evaluating the association of vitamin D-related genetic variants with breast cancer risk have produced inconsistent results. METHODS: We evaluated the association between breast cancer risk and 559 single-nucleotide polymorphisms (SNP) in 12 vitamin D-related genes, including 6 genes associated with circulating 25-hydroxyvitamin D [25(OH)D] level identified by recent genome-wide association studies (GWAS), using directly observed and imputed GWAS genotyping data from 2,919 breast cancer cases and 2,323 controls recruited in the Shanghai Breast Cancer Study. RESULTS: Of the SNPs studied, only rs12570116 in the ACADSB gene, rs4760658 in the VDR gene and rs6091822, rs8124792, and rs6097809 in the CYP24A1 gene, and rs10902845 in C10orf88 had a nominal association with breast cancer risk (P < 0.05 for all). None of these associations persisted after adjustment for multiple comparisons. The most extensively studied SNPs including rs10735810, also known as rs2228570 (Fok1, VDR), rs1544410 (Bsm1, VDR), and rs2296241 (CYP24A1), were not associated with breast cancer risk. GWAS-identified genetic variants that were associated with 25(OH)D were also not related to breast cancer risk. CONCLUSIONS: Our data suggest that genetic polymorphisms in vitamin D-related genes do not play a major role in breast cancer risk in Chinese women. IMPACT: Although our study confirms previously documented breast cancer risk factor associations, our null results suggest that common genetic variants in vitamin D genes and loci associated with control of vitamin D levels are not risk factors for breast cancer in Chinese women. Our data contribute to filling the gap in this field of research.

Obesity, age, and oxidative stress in middle-aged and older women.

Recent evidence suggests that urinary F(2)-isoprostanes (F(2)-IsoPs) are more accurate markers of oxidative stress than other available biomarkers. Most previous studies used unmetabolized F(2)-IsoPs as a biomarker. Few previous studies measured 15-F(2t)-IsoP-M, a metabolite of one of the most common F(2)-IsoPs, 15-F(2t)-IsoP. Unlike 15-F(2t)-IsoP, 15-F(2t)-IsoP-M is not subject to autoxidation and renal production. To our knowledge, no study has compared the associations of age and body mass index (BMI) with F(2)-IsoPs to those with 15-F(2t)-IsoP-M. Urinary levels of F(2)-IsoPs and 15-F(2t)-IsoP-M were measured using gas chromatography-mass spectrometry for 845 healthy women aged 40-70 years. Both F(2)-IsoPs and 15-F(2t)-IsoP-M were elevated among smokers. The level of 15-F(2t)-IsoP-M increased with age, particularly after menopause, and with BMI. In contrast, F(2)-IsoPs decreased with age, regardless of menopausal status, and was not related to BMI. The association of 15-F(2t)-IsoP-M with age or menopausal status did not differ by BMI category, and the association with BMI was also independent of age or menopausal status. 15-F(2t)-IsoP-M appears to be a valuable biomarker of oxidative stress in age- and obesity-related diseases.

Soy intake in association with menopausal symptoms during the first 6 and 36 months after breast cancer diagnosis.

It has been suggested that soy food and its components may relieve menopausal symptoms (MPS) including hot flashes, night sweats, and vaginal dryness in healthy women. However, little is known about the effect of soy food intake on MPS in women with breast cancer. We examined associations of occurrence of MPS with soy food intake in 4,842 Chinese women aged 20-75 years who had non-metastatic breast cancer and had not used hormone replacement therapy. MPS were assessed at 6 and 36 months after cancer diagnosis using a standardized questionnaire, and associations with soy food intake were evaluated in multivariate regression analyses. Daily soy food intake was assessed at 6 months postdiagnosis and over the first 36 months postdiagnosis using a validated food frequency questionnaire. The prevalence of MPS was 56% at 6 months and 63% at 36 months postdiagnosis with the hotflash being the most common MPS (~44-55%). Hot flashes occurred mainly in premenopausal breast cancer patients who were in the highest quartile of isoflavone intake at 6 months postdiagnosis (OR = 1.20, 95% CI: 0.98-1.59) compared with the lowest quartile. This association was stronger at 36 months postdiagnosis (OR = 1.59, 95% CI: 1.02-2.48). We found no significant associations for any MPS, night sweats, or vaginal dryness. Neither tamoxifen use nor BMI modified the association between MPS and isoflavone intake. There was no evidence that soy food consumption reduced MPS among breast cancer patients. High soy intake may increase the prevalence of hotflashes among premenopausal patients. Our study suggests that soy acts as an estrogen antagonist in breast cancer patients.

Impact of menopausal symptoms on quality of life 6 months after systemic breast cancer treatment: results from the Shanghai Breast Cancer Survival Study.

Menopausal symptoms (MPS) after breast cancer treatment are associated with reduced health-related quality of life (QOL) among Caucasian women. Little is known about whether MPS similarly impact QOL in Asian women with breast cancer. QOL was assessed by using the generic quality of life instruments, Medical Outcome Study of Quality of Life Inventory (MOSQOL-74) or Short Form-36 Health Survey (SF-36) in 4,976 Chinese participants of the Shanghai Breast Cancer Survival Study who were treated for incident, non-metastatic breast cancer within the 6 months before the study interview. Relationships between MPS and QOL were assessed by multiple linear regression, controlling for potential confounders. About 71.4% of study participants experienced MPS, including hot flashes, night sweats, vaginal dryness, depressed mood, and/or dry skin. Women with MPS reported lower overall QOL than women without MPS [mean scores 61.0 vs. 64.0, respectively (MOSQOL-74) and 54.9 vs. 66.9, respectively (SF-36); P < 0.01]. Adjusted mean differences (beta) in overall QOL in the presence and absence of MPS were -3.1 (95% CI -3.8, -2.4) with the MOSQOL-74 and -12.3 (95% CI -13.8, -10.9) with the SF-36. Women with any MPS had lower scores for the MOSQOL-74 physical and psychological domains and for the SF-36 social and emotional subscales than those without MPS (P < 0.05 for all). Having several MPS predicted poorer QOL in all domains measured regardless of the instrument used (P (trend) < 0.01 for all). Our study indicates that in Chinese women recently treated for breast cancer, MPS adversely impacts QOL. Actively soliciting and treating MPS in these women should significantly improve their QOL.

Risk factors for HIV infection among Haitian adolescents and young adults seeking counseling and testing in Port-au-Prince.

OBJECTIVES: Many Haitian adolescents and youth are highly vulnerable to HIV infection. It was important to define the risk factors of the young people who are already seeking care. METHODS: Among 3391 sexually active 13- to 25-year-olds in our Voluntary Counseling and Testing (VCT) Center in Port-au-Prince from October 2005 to September 2006, we assessed associations between demographic and behavioral factors and HIV status using multivariable logistic regression analyses. RESULTS: We diagnosed HIV infection in 6.3% of 2533 females and 5.5% of 858 males. Age-specific prevalence was 3.4% for 13- to 15-year-olds, 4.7% for 16-19, and 6.8% for 20-25 (P = 0.02). Poor education, not residing with parents, currently or formerly married, having a child, and being self-referred or referred by others VCT services were significant predictors of HIV in females. HIV infection was associated with considering oneself at higher risk, although most youth did not recognize this risk. HIV in females was also associated with suspected/confirmed sexually transmitted infection, especially genital ulcers (ORadj = 2.28, 95% confidence interval: 1.26 to 4.13), years of sexual activity (Ptrend = 0.07), and suspicion that partners had other partners or an sexually transmitted infection. Among males, HIV was associated with drug use (though uncommon) and sexual debut with a casual/unknown person (ORadj = 3.18, 95% confidence interval: 1.58 to 6.42). HIV-infected young people were more likely to be rapid plasma reagin positive and less likely to use condoms. CONCLUSION: Young Haitians are a key target for HIV prevention and care and avail themselves readily of youth-focused VCT services.

Menopausal symptoms among breast cancer patients 6 months after diagnosis: a report from the Shanghai Breast Cancer Survival Study.

OBJECTIVE: The aim of this study was to estimate the prevalence of menopausal symptoms in relation to treatment modalities in Asian women treated for breast cancer. METHODS: A population-based cohort of 5,023 Chinese women aged 25 to 70 years with primary stage 0 to III breast cancer was identified from a population-based tumor registry and enrolled in the study approximately 6 months after diagnosis. Participants were asked about the occurrence of specific menopausal symptoms. Associations between these symptoms and breast cancer treatments were evaluated by stratified, multivariate logistic regression. RESULTS: Among women with a recent diagnosis of breast cancer, 67.2% of premenopausal women and 46.3% of postmenopausal women experienced at least one menopausal symptom, namely, hot flashes, night sweats, and/or vaginal dryness. Symptom prevalence among postmenopausal women decreased progressively with age at diagnosis (63.3% for women aged 51-55 y, 51.5% for women aged 56-60 y, and 34.4% for women aged >65 y; P < 0.01). Overall, the highest prevalence of most symptoms occurred in women aged 46 to 55 years (P < 0.01). Chemotherapy was positively associated with the occurrence of any symptom and with each individual symptom, mainly in premenopausal women (adjusted odds ratio [OR] range, 2.2-3.3; P < 0.05 for all). Tamoxifen use and immunotherapy were associated with having any symptom and with each individual symptom, regardless of menopause status (adjusted OR range, 1.5-1.8 and 1.3-1.5, respectively; P < 0.05 for all). Women treated before menopause were at particularly high risk of experiencing two or more symptoms after chemotherapy (OR, 1.77; 95% CI, 1.54-4.98; P interaction = 0.05) compared with postmenopausal women. CONCLUSIONS: Menopausal symptoms are prevalent among Chinese women recently treated for primary breast cancer. These symptoms are associated with age and menopause status at the time of diagnosis, as well as with the type of treatment received.

Relation of blood pressure components and categories and all-cause, stroke and coronary heart disease mortality in urban Chinese women: a population-based prospective study.

OBJECTIVE: To determine whether various levels of blood pressure (BP), particularly normal and high normal BP or prehypertension, predict cardiovascular mortality among urban Chinese women. METHODS: We evaluated the impact of all measures of BP on total mortality and stroke and coronary heart disease (CHD)-specific mortality in a population-based cohort study, the Shanghai Women's Health Study. Included in this analysis were 68 438 women aged 40-70 years at baseline for whom BP was assessed. RESULTS: During an average of 5 years of follow-up, we identified 1574 deaths from all causes, 247 from stroke and 91 from CHD. Hypertension and higher levels of individual BP parameters including systolic BP, diastolic BP, pulse pressure, and mean arterial pressure were positively associated with all-cause, stroke, and CHD mortality (Ptrend < 0.05 for all except for DBP and CHD mortality). Prehypertension [adjusted hazard ratio (HRadj) = 1.65; 95% confidence interval, 0.98-2.78], particularly high normal BP (HRadj = 2.34; 95% confidence interval, 1.32-4.12), was associated with an increased risk of mortality from stroke. Hypertension accounted for 9.3% of mortality from all causes, 25.5% of mortality from stroke, and 21.7% mortality from CHD. High normal BP accounted for 10.8% of mortality from stroke. Isolated systolic BP also predicted stroke and mortality from CHD. CONCLUSION: Hypertension is a significant contributor to mortality, particularly stroke and CHD mortality, among women in Shanghai. High normal BP is associated with high stroke mortality.

Use of oral contraceptives, intrauterine devices and tubal sterilization and cancer risk in a large prospective study, from 1996 to 2006.

The association of contraceptive methods, including oral contraceptives (OC), intrauterine devices (IUD) and tubal sterilization (TS), with overall and site-specific cancer were prospectively investigated in a cohort of 66,661 Chinese women in Shanghai, 76.7% of whom used contraception. During a median follow-up time of 7.5 years, 2,250 women were diagnosed with cancer. Ever-use of any contraceptive method was not associated with overall cancer risk [adjusted hazard ratio (HR(adj)) = 1.02, 95% CI, 0.92-1.12]. Use of any contraceptive method was associated with increased risk of rectal cancer (HR(adj) = 1.68, 95% CI, 1.08-2.62) and reduced risk of thyroid cancer (HR(adj) = 0.63, 95% CI, 0.38-1.04). Risk of gallbladder cancer increased with ever use of OC (HR(adj) = 2.38, 95% CI, 1.26-4.49). IUD use was associated with a possible reduced risk of thyroid cancer (HR(adj) = 0.64, 95% CI, 0.38-1.07). Longer duration of IUD use decreased risk for breast, thyroid and lung cancers. Ever having a TS was associated with increased uterine body cancer (HR(adj) = 2.50, 95% CI, 1.47-4.25) and decreased risk of stomach cancer (HR(adj) = 0.59, 95% CI, 0.39-0.91). We did not find any contraceptive method to be related to the risk of ovarian cancer but the analyses were based on few events. Although chance findings are a likely explanation for some of the associations found in our study, these findings suggest that various contraceptive methods or reproductive patterns may play a role in the etiology of cancer.

Plasma carotenoids, tocopherols, retinol and breast cancer risk: results from the Shanghai Women Health Study (SWHS).

Evidence from some previous studies suggests that lipophilic antioxidants, particularly carotenoids, may reduce the risk of breast cancer. We prospectively investigated the associations of plasma levels of tocopherols, retinol, carotenoids with the risk of developing breast cancer among Chinese women. We conducted a study of 365 incident breast cancer cases and 726 individually matched controls nested within a large cohort study of women aged 40-70 years at baseline. We observed no associations between breast cancer risk and any of the tocopherols, retinol, and most carotenoids. However, high levels of plasma lycopene other than trans, 5- and 7-cis or trans alpha-cryptoxanthin were inversely associated with the risk of developing breast cancer. Our results do not support an overall protective effect of lipophilic antioxidants on breast cancer risk. The few inverse associations observed for subtype of carotenoids may need to be confirmed in future studies.

Dietary and lifestyle predictors of age at natural menopause and reproductive span in the Shanghai Women's Health Study.

OBJECTIVE: Modifiable factors predicting the onset of menopause, a transition with important implications for women's health, have not been fully characterized. We evaluated the impact of dietary, lifestyle and reproductive factors on age at natural menopause and reproductive span in Chinese women. DESIGN: Study participants were Chinese women aged 40 to 70 who experienced natural menopause and participated in a population-based, prospective study, the Shanghai Women's Health Study (N = 33,054). Dietary intake at the baseline survey was assessed by food-frequency questionnaire. Regression (beta) coefficients, calculated by multivariable linear regression, were used to estimate the effects of dietary, lifestyle, and reproductive patterns on age at menopause and the number of reproductive years, adjusting for potential confounding factors. RESULTS: Early menarche, younger age at first live birth, older age at last live birth, longer duration of breast-feeding, and higher parity were associated with longer reproductive years (Ptrend < 0.01 for all). Higher body mass index at age 20, mid-life weight gain, and leisure-time physical activity during adolescence and adulthood predicted later menopause and longer reproductive span (Ptrend < 0.01 for all). Total intake of calories, fruits, and protein was positively associated with later menopause (Ptrend < 0.05 for all) and longer reproductive span (Ptrend < 0.05), except for carbohydrates (Ptre(nd) = 0.06), and long-term tea consumption predicted longer reproductive span (Ptrend = 0.03). Vegetable, fat, soy, and fiber intakes did not significantly affect reproductive span or age at menopause. Smoking was inversely associated with both early age at menopause and shorter reproductive span (Ptrend < 0.01). CONCLUSIONS: In addition to reproductive factors, intake of fruits and protein, smoking, tea consumption, lifetime patterns of physical activity, and weight gain influenced the onset of menopause and/or reproductive span in Chinese women.

History of benign breast disease and risk of breast cancer among women in China: a case-control study.

BACKGROUND: Data from the Shanghai Breast Cancer Study were analyzed to evaluate the relationship between benign breast disease (BBD) and breast cancer among Chinese women with a self-report of physician-diagnosed BBD. METHODS: Study participants consisted of 3,452 breast cancer cases and 3,474 population controls recruited by the Shanghai Breast Cancer Study. In-person interviews were conducted to collect information on demographics and suspected risk factors for breast cancer, including a detailed history of BBD. Unconditional logistic regression was used to derive adjusted odds ratios (OR(adj)) and 95% confidence intervals (CI) for the association between self-reported BBD and breast cancer. RESULTS: Women with breast cancer were significantly more likely to have a self-reported history of BBD including lobular proliferation (OR(adj) = 1.6; 95% CI 1.4-1.8), fibroadenoma (OR(adj) = 1.9; 95% CI 1.6-2.3), and other BBD (OR(adj) = 1.6; 95% CI 1.3-2.1). Breast cancer risk was lower for surgically treated fibroadenoma as compared to non-surgically treated and higher for other BBDs that were surgically treated versus non-surgically treated. CONCLUSIONS: Our results suggest that personal history of BBD is associated with an increased risk of future breast cancer among women in China. Surgical intervention for fibroadenoma may reduce the risk.

Vitamin supplement use and risk for breast cancer: the Shanghai Breast Cancer Study.

OBJECTIVE: The influence of vitamin supplements on breast cancer risk is unclear and the interactive effects of dietary and supplemental sources are unknown. This study investigated (1) the association between self-reported vitamin supplement use (multivitamin, A, B, C, and E) and breast cancer and (2) the combined effect of vitamin supplements in relation to dietary vitamin intakes on breast cancer risk. METHODS: The Shanghai Breast Cancer Study was a population-based case-control study conducted in Shanghai in 1996-1998 (Phase I) and 2002-2004 (Phase II). Participants were aged 25-64 (Phase I) and 20-70 years (Phase II). The analyses included 3,454 incident breast cancer cases and 3,474 controls. Unconditional logistic regression models were used to determine adjusted odds ratios (ORs) for breast cancer risk associated with vitamin supplement use. RESULTS: Overall, breast cancer risk was not related to any vitamin supplement intake. However, a 20% reduction in breast cancer risk was observed with vitamin E supplement use among women with low-dietary vitamin E intake (OR = 0.8; 95% confidence interval (CI), 0.6-1.0). A non-significant 20% risk reduction was observed among vitamin B supplement users with low B dietary intake (OR = 0.8; 95% CI, 0.6-1.1). Frequent use of a vitamin B supplement was adversely associated with breast cancer risk among those with high dietary vitamin B intake (OR = 1.4; 95% CI: 0.9-2.1; P for interaction = 0.07). CONCLUSIONS: This study suggests that vitamins E and B supplements may confer protection against breast cancer among women who have low dietary intake of those vitamins.