Association between reproductive factors with lung cancer incidence and mortality: A pooled analysis of over 308,000 females in the Asia cohort consortium.

Previous studies have investigated the association between reproductive factors and lung cancer risk; however, findings have been inconsistent. In order to assess this association among Asian women, a total of 308,949 female participants from 11 prospective cohorts and four Asian countries (Japan, Korea, China, and Singapore) were included. Cox proportional hazards regression models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CIs). A total of 3,119 primary lung cancer cases and 2247 lung cancer deaths were identified with a mean follow-up of 16.4 years. Parous women had a lower risk of lung cancer incidence and mortality as compared with nulliparous women, with HRs of 0.82 (95% CI = 0.70-0.96) and 0.78 (95% CI = 0.65-0.94). The protective association of parity and lung cancer incidence was greater among ever-smokers (HR = 0.66, 95% CI = 0.49-0.87) than in never-smokers (HR = 0.90, 95% CI = 0.74-1.09) (P-interaction = 0.029). Compared with age at first delivery ≤20 years, older age at first delivery (21-25, ≥26 years) was associated with a lower risk of lung cancer incidence and mortality. Women who ever used hormone replacements had a higher likelihood of developing non-small cell lung cancer (HR = 1.31, 95% CI = 1.02-1.68), compared to those who never used hormone replacements. Future studies are needed to assess the underlying mechanisms, the relationships within these female reproductive factors, and the potential changes in smoking habits over time.

Association between Vitamin A and E Forms and Prostate Cancer Risk in the Singapore Prostate Cancer Study.

PURPOSE: This study aimed to assess associations between forms of vitamin A and E (both individually and collectively) and the risk of prostate cancer, as well as identify potential effect modifiers. METHODS: Utilizing data from the Singapore Prostate Cancer Study, a hospital-based case-control study, we measured the serum concentrations of 15 different forms of vitamins A and E in 156 prostate cancer patients and 118 control subjects, using a high-performance liquid chromatography technique. These forms included retinol, lutein, zeaxanthin, α-cryptoxanthin, ß-cryptoxanthin, α-carotene, ß-carotene, lycopene, ubiquinone, δ-tocopherol, γ-tocopherol, α-tocopherol, δ-tocotrienol, γ-tocotrienol, and α-tocotrienol. The odds ratio and 95% confidence interval for associations between vitamin A and E and prostate cancer risk were estimated using logistic regression models after adjustment for potential confounders. The analyses were further stratified by smoking and alcohol consumption status. The mixture effect of micronutrient groups was evaluated using weighted quantile sum regression. RESULTS: Higher concentrations of retinol, lutein, α-carotene, ß-carotene, ubiquinone, α-tocopherol, δ-tocotrienol, γ-tocotrienol, and α-tocotrienol were significantly and positively associated with overall prostate cancer risk. Among ever-smokers, associations were stronger for lutein, ß-cryptoxanthin and ß-carotene compared with never-smokers. Among regular alcohol drinkers, associations were stronger for lutein, ß-cryptoxanthin, ubiquinone, γ-tocotrienol and α-tocotrienol compared with non-regular alcohol drinkers. Retinol and α-tocotrienol contributed most to the group indices 'vitamin A and provitamin A carotenoids' and 'vitamin E', respectively. CONCLUSIONS: Several serum vitamin A and E forms were associated with prostate cancer risk, with significant effect modification by smoking and alcohol consumption status. Our findings shed light on prostate cancer etiology.

Risk Factors for Hyperuricemia or Gout in Men and Women: The Circulatory Risk in Communities Study (CIRCS).

AIM: We aimed to examine sex-specific risk factors for hyperuricemia or gout in Japanese cohorts. METHODS: We followed up 3,188 men (mean age, 55.6 years) and 6,346 women (mean age, 54.1 years) without hyperuricemia, gout, or elevated liver enzymes at baseline from 1986 to 1990 for a median of 14.6 years. The participants were considered as having hyperuricemia or gout if their serum uric acid levels were ≥ 7.0 mg/dL or they were receiving treatment for hyperuricemia or gout during annual health checkups. The sex-specific multivariable hazard ratios (HRs) of hyperuricemia or gout incidence were calculated after adjustment for smoking and drinking status, body mass index, hypertension, diabetes, hypercholesterolemia, and hypertriglyceridemia using the Cox proportional-hazard model. RESULTS: During follow-up, 733 men and 355 women had hyperuricemia or gout. Among men, the multivariable HRs (95% confidence intervals) of hyperuricemia or gout were 1.23 (1.00-1.52) and 1.41 (1.13-1.75) for drinkers of ＜46 and ≥ 46 g ethanol/day, respectively, compared with non-drinkers; 1.00 (0.81-1.24) and 1.18 (0.93-1.50) for smokers of 1-19 and ≥ 20 cigarettes/day, respectively, compared with never smokers; and 1.41 (1.20-1.65) for hypertensive compared with non-hypertensive participants. The HRs for women were 1.02 (0.70-1.48), 1.66 (1.05-2.63), and 1.12 (0.88-1.42) for current drinkers, current smokers, and hypertensive participants, respectively. For both men and women, body mass index, diabetes, hypercholesterolemia, and hypertriglyceridemia were not associated with hyperuricemia or gout incidence. CONCLUSIONS: Hypertension and alcohol drinking are risk factors for hyperuricemia or gout among men and smoking among women.

Relationships between Age at Menarche and Risk of Cardiovascular Disease Mortality among Japanese Women: The Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC) Study.

AIM: In this study, we aimed to evaluate the association between age at menarche and risk of cardiovascular disease mortality. METHODS: In total, 54,937 women aged 40-79 years old between 1988 and 1990 without a history of cardiovascular disease were eligible for analysis and were followed through December 2009. We used the Cox proportional hazards models to examine the association between age at menarche and risk of cardiovascular disease. RESULTS: Compared with women with age at menarche of 15 years, the hazard ratios (95% confidence intervals) of stroke were 1.22 (0.85-1.75) for women with age at menarche of 9-12 years, 1.08 (0.85-1.36) for those of 13 years, 1.23 (1.02-1.47) for those of 14 years, 1.27 (1.07-1.50) for those of 16 years, 1.16 (0.95-1.41) for those of 17 years, and 1.39(1.16-1.68) for those of 18-20 years (P for trend=0.045). A similar pattern was observed for hemorrhagic stroke, ischemic stroke, and total cardiovascular disease. No such association was found for coronary heart disease. When stratified by age, for women aged 40-59 at baseline, the similar U-shaped association was observed. In contrast, for women aged 60-79 years at baseline, a significantly high hazard ratio was noted in the group of late age at menarche, but not in the group of early age at menarche. CONCLUSIONS: Both women with early and late age at menarche were determined to have higher risk of death from stroke and cardiovascular disease.

Dietary intake of beans and risk of disabling dementia: The Circulatory Risk in Communities Study (CIRCS).

OBJECTIVE: To examine whether bean intake (including soybeans) among Japanese adults is associated with risk of disabling dementia severe enough to require care under the national insurance system. METHODS: This cohort study involved 3739 individuals aged 40 to 64 years. The participants were categorized into five groups based on their dietary bean intake estimated by a 24h dietary recall. Hazard ratios and 95% confidence intervals of disabling dementia were estimated using Cox proportional hazard models adjusted for potential confounding factors (smoking, drinking, and intakes of energy and fish). RESULTS: During the 59,681 person-year follow-up, 670 cases of disabling dementia were observed. A weak inverse association between bean intake and risk of disabling dementia was found; the multivariable hazard ratios (95% CIs) were 0.79 (0.62-1.00), 0.80 (0.63-1.01), 0.84 (0.67-1.06), and 0.78 (0.62-0.99) for the four groups with higher bean intake, respectively, compared with the lowest group (P for trend = 0.21). A significant inverse association was observed for dementia without a history of stroke; for the four groups with higher bean intake the multivariable hazard ratios were 0.81 (0.61-1.08), 0.70 (0.52-0.95), 0.71 (0.52-0.95), and 0.69 (0.51-0.92), respectively, (P for trend = 0.03). No such association was observed for dementia with history of stroke. The group with increased natto intake were inversely associated with risk of disabling dementia (P for trend = 0.003), but tofu intake was not (P for trend = 0.19). CONCLUSIONS: Bean intake was inversely associated with risk of disabling dementia in those without a history of stroke.

Impact of seaweed intake on health.

Seaweeds contain minerals, vitamins, soluble dietary fibers, and flavonoids, which are regarded as preventive agents against lifestyle-related diseases. Seaweeds are consumed commonly in East Asian countries including Japan. Thus, intake of seaweeds might contribute to Japanese longevity via prevention of lifestyle-related diseases. Recently, two large Japanese cohort studies have reported the association of seaweed intake with reduced risk of cardiovascular diseases. On the other hand, seaweeds also contain iodine and heavy metals such as arsenic species, which are considered to have adverse effects on health. We here reviewed studies of the association between seaweed intake and mortality from or incidence of cancer and cardiovascular diseases, and their risk factors such as blood pressure or serum lipids. We also summarized the adverse effects of iodine and arsenic species in seaweeds. Although seaweeds have not been widely consumed in Western countries, dietary diversification and an increased proportion of immigrants from East Asia may increase seaweed consumption in those countries. Further epidemiological studies including observational and interventional studies are necessary to clarify the effects of seaweeds on disease and health.

Frequency of Seaweed Intake and Its Association with Cardiovascular Disease Mortality: The JACC Study.

AIM: Seaweed is a popular traditional foodstuff in Asian countries. To our knowledge, few studies have examined the association of seaweed intake with mortality from cardiovascular disease. We examined the association of frequency of seaweed intake with total and specific cardiovascular disease mortality. METHODS: We examined the association of seaweed intake with mortality from cardiovascular disease among 40,234 men and 55,981 women who participated in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk. Sex-specific hazard ratios for mortality from cardiovascular disease (stroke, stroke subtypes, and coronary heart disease) according to the frequency of seaweed intake were calculated stratified by study area and adjusted for potential cardiovascular risk factors and dietary factors. RESULTS: During the 1,580,996 person-year follow-up, 6,525 cardiovascular deaths occurred, of which 2,820 were due to stroke, and 1,378, to coronary heart disease. Among men, the multivariable analysis showed that participants who ate seaweed almost every day compared with those who never ate seaweed had hazard ratios (95% confidence interval; P for trend) of 0.79 (0.62-1.01; 0.72) for total cardiovascular disease, 0.70 (0.49-0.99; 0.47) for total stroke, 0.69 (0.41-1.16; 0.11) for cerebral infarction. Among women, the multivariable-adjusted hazard ratios were 0.72 (0.55-0.95; 0.001) for total cardiovascular disease, 0.70 (0.46-1.06; 0.01) for total stroke, and 0.49 (0.27-0.90; 0.22) for cerebral infarction. No associations were observed between seaweed intake and risk of intraparenchymal hemorrhage and coronary heart disease among either men or women. CONCLUSIONS: We found an inverse association between seaweed intake and cardiovascular mortality among Japanese men and women, especially that from cerebral infarction.