Sawada N.,Epidemiology and Prevention Group |
Sawada N.,Research Center for Cancer Prevention and Screening |
Iwasaki M.,Epidemiology and Prevention Group |
Yamaji T.,Epidemiology and Prevention Group |
And 5 more authors.
American Journal of Clinical Nutrition | Year: 2015
Background: Dietary fiber may reduce the risk of prostate cancer, possibly by increasing circulating concentrations of sex hormone-binding globulin and improving insulin sensitivity. However, results from previous epidemiologic studies of fiber intake and prostate cancer are inconsistent, and to our knowledge, no study has comprehensively evaluated the effects of soluble and insoluble fiber on prostate cancer in Asia. Objective: The objective was to examine the association between fiber intake and prostate cancer in Japanese men. Design: We conducted a population-based prospective study in 43,435 Japanese men aged 45-74 y. Participants responded to a validated questionnaire, which included 138 food items. Follow-up was from 1995 through 2009. HRs and 95% CIs of incidence were calculated according to quartiles of fiber intake. Results: During the 11.6-y follow-up, of the 825 men newly diagnosed with prostate cancer, 213 had advanced-stage cancer, 582 had organ-localized disease, and 30 had an undetermined stage of disease. Among them, 217 cases were detected by subjective symptoms. Total fiber was not associated with total or advanced prostate cancer, with respective multivariable HRs for the highest and lowest quartiles of 1.00 (95% CI: 0.77, 1.29; P-trend = 0.97) and 0.67 (95% CI: 0.42, 1.07; P-trend = 0.30). Total fiber and insoluble fiber intake were associated with a decreased risk of advanced cancers detected by subjective symptoms, with multivariate HRs (95% CIs) across increasing quartiles of 1.00, 0.58, 0.62, and 0.44 (0.21, 0.92; P-trend = 0.05) for total fiber and 1.00, 0.60, 0.52, and 0.46 (0.22, 0.93; P-trend = 0.04) for insoluble fiber. Soluble fiber intake showed no association with prostate cancer. Conclusions: Dietary fiber is inversely associated with advanced prostate cancer detected by subjective symptoms even among populations with relatively low intake, such as Japanese. These results suggest that a very low intake of dietary fiber is associated with an increased risk of prostate cancer. © 2015 American Society for Nutrition
PubMed | Epidemiology and Prevention Group, Japan National Cardiovascular Center Research Institute and University of Tokyo
Type: | Journal: International journal of cancer | Year: 2017
Few studies have examined the association between smoking behavior (especially quitters) at the time of diagnosis and mortality among cancer patients. Our objective was to examine the benefits of quitting on all-cause mortality among cancer patients. 30,658 eligible cancer patients diagnosed between 1985 and 2009, identified by a hospital-based cancer registry in Japan, were followed up for up to 10 years. We evaluated smoking behavior at cancer diagnosis (especially recent quitters vs. current smokers) in association with all-cause mortality using Cox-proportional hazards models and covariates-adjusted survival curves. Risk of death was estimated to be reduced by 11% in recent quitters compared with current smokers. According to adjusted survival curves, median survival time was 8.25 years for recent quitters versus 7.18 years for current smokers, indicating an absolute difference of 1.07 year for a median survivor. Similarly, never and former smokers had 18% and 16% lower risk of death with 1.90 years and 1.77 years gained, respectively, compared with current smokers. In addition to former and never smokers, recent quitters showed consistently higher survival rates than current smokers during the 10-year calendar period after diagnosis among cancer patients. Because recent quitters may be similar to patients who stop smoking shortly after cancer diagnosis in terms of smoking duration, the latter may be able to decrease their risk of death, suggesting that smoking cessation could be part of cancer care.
PubMed | Epidemiology and Prevention Group, Tohoku University, Kyushu University, Nagoya University and 4 more.
Type: Journal Article | Journal: PloS one | Year: 2016
Differences in DNA collection protocols may be a potential confounder in epigenome-wide association studies (EWAS) using a large number of blood specimens from multiple biobanks and/or cohorts. Here we show that pre-analytical procedures involved in DNA collection can induce systematic bias in the DNA methylation profiles of blood cells that can be adjusted by cell-type composition variables. In Experiment 1, whole blood from 16 volunteers was collected to examine the effect of a 24 h storage period at 4C on DNA methylation profiles as measured using the Infinium HumanMethylation450 BeadChip array. Our statistical analysis showed that the P-value distribution of more than 450,000 CpG sites was similar to the theoretical distribution (in quantile-quantile plot, = 1.03) when comparing two control replicates, which was remarkably deviated from the theoretical distribution ( = 1.50) when comparing control and storage conditions. We then considered cell-type composition as a possible cause of the observed bias in DNA methylation profiles and found that the bias associated with the cold storage condition was largely decreased ( adjusted = 1.14) by taking into account a cell-type composition variable. As such, we compared four respective sample collection protocols used in large-scale Japanese biobanks or cohorts as well as two control replicates. Systematic biases in DNA methylation profiles were observed between control and three of four protocols without adjustment of cell-type composition ( = 1.12-1.45) and no remarkable biases were seen after adjusting for cell-type composition in all four protocols ( adjusted = 1.00-1.17). These results revealed important implications for comparing DNA methylation profiles between blood specimens from different sources and may lead to discovery of disease-associated DNA methylation markers and the development of DNA methylation profile-based predictive risk models.
PubMed | Epidemiology and Prevention Group, Tokyo Electron, National Institute of Mental Health, Osaka University and 3 more.
Type: Journal Article | Journal: Diabetes & metabolism | Year: 2016
This study looked at whether a history of diabetes mellitus (DM) is associated with a higher risk of externally caused death (by suicide and accident), using data for a large population-based prospective cohort from an Asian population.Data collected between 1990 and 2012 from the Japan Public Health Centre-based Prospective Study were analyzed, and Poisson regression models were used to calculate adjusted risk ratios (RR) for external causes of death.The population-based cohort comprised 105,408 Japanese residents (49,484 men and 55,924 women; mean age: 51.2 [SD 7.9] years). At baseline, 3250 (6.6%) men and 1648 (3.0%) women had a history of DM. During the follow-up period, 113 external deaths (41 suicides and 72 accidents) were noted among those with a history of DM, with 1304 external deaths (577 suicides and 727 accidents) among those without such a history. A higher risk of external death (men, RR: 1.4, 95% CI: 1.2-1.8; women, RR: 1.6, 95% CI: 1.01-2.4) was observed in those with a history of DM. Also, among those aged 40-49 years (RR: 1.9, 95% CI: 1.3-2.7) and 50-59 years (RR: 1.4, 95% CI: 1.05-1.9) at baseline, the risk of external death was significantly higher in those with a history of DM.Compared with people with no history of DM, those with such a history had a significantly greater risk of externally caused death (particularly accidental deaths) in both genders and in those aged59 years at baseline.
PubMed | Osaka University, Epidemiology and Prevention Group and Sagami Women's University
Type: Journal Article | Journal: Cancer science | Year: 2016
Green tea and coffee consumption may decrease the risk of some types of cancers. However, their effects on biliary tract cancer (BTC) have been poorly understood. In this population-based prospective cohort study in Japan, we investigated the association of green tea (total green tea, Sencha, and Bancha/Genmaicha) and coffee consumption with the risk for BTC and its subtypes, gallbladder cancer, and extrahepatic bile duct cancer. The hazard ratios and 95% confidence intervals were calculated using the Cox proportional hazard model. A total of 89555 people aged 45-74years were enrolled between 1995 and 1999 and followed up for 1138623 person-years until 2010, during which 284 cases of BTC were identified. Consumption of >720mL/day green tea was significantly associated with decreased risk compared with consumption of 120mL/day (hazard ratio=0.67 [95% confidence interval, 0.46-0.97]), and a non-significant trend of decreased risk associated with increased consumption was observed (P-trend=0.095). In the analysis according to the location of the primary tumor, consuming >120mL green tea tended to be associated with decreased risk of gallbladder cancer and extrahepatic bile duct cancer. When Sencha and Bancha/Genmaicha were analyzed separately, we observed a non-significant trend of decreased risk of BTC associated with Sencha but no association with Bancha/Genmaicha. For coffee, there was no clear association with biliary tract, gallbladder, or extrahepatic bile duct cancer. Our findings suggest that high green tea consumption may lower the risk of BTC, and the effect may be attributable to Sencha consumption.
PubMed | Radiation Effects Research Foundation, Epidemiology and Prevention Group, The Research Center for Hepatitis and Immunology, Nagoya City University and Nagasaki University
Type: Journal Article | Journal: Cancer causes & control : CCC | Year: 2016
Adult T-cell leukemia/lymphoma (ATLL) is an aggressive hematological malignancy caused by human T-cell leukemia virus type-1 (HTLV-1); no effective methods have yet been identified to prevent development of ATLL in carriers of HTLV-1. This study investigated the association between cigarette smoking and the risk of ATLL development among Japanese carriers of HTLV-1.This study examined the association between smoking and development of ATLL in a cohort of 1,332 Japanese HTLV-1 carriers aged 40-69years free of ATLL at baseline from two different HTLV-1-endemic areas of Japan. Cox proportional hazards models adjusted for sex, geographic area, age at baseline, and alcohol drinking were used to estimate the effect of cigarette smoking on ATLL development.Between 1993 and 2012, 25 new ATLL cases were identified among these subjects. The overall crude incidence rate for ATLL was 1.08 per 1,000 person-years among HTLV-1 carriers and was higher among male carriers than among female carriers (2.21 vs. 0.74). The risk of ATLL development increased significantly with increasing numbers of cigarettes smoked per day (hazard ratio for every increment of 20 cigarettes, 2.03; 95% confidence interval (CI) 1.13-3.66 overall, 2.07 (95% CI 1.13-3.73) in male carriers).Cigarette smoking may influence ATLL development among HTLV-1 carriers in Japan.
Sawada N.,Epidemiology and Prevention Group
European Journal of Clinical Nutrition | Year: 2016
Background/Objectives:Although vitamin D has been experimentally reported to inhibit tumorigenesis, cell growth and prostate cancer invasion, epidemiologic data regarding prostate cancer risk are inconsistent, and some studies have suggested positive but nonsignificant associations. Further, the impact of vitamin D on prostate cancer between Western and Japanese populations may differ due to different plasma vitamin D levels.Subjects/Methods:We performed a nested case–control study within the Japan Public Health Center–based Prospective (JPHC) Study in 14,203 men (40–69 years) who answered a self-administered questionnaire at baseline (1990–1994) and gave blood samples, and were followed until 2005. We identified 201 prostate cancers which are newly diagnosed during follow-up (mean 12.8 years). We selected two matched controls for each case from the cohort. We used a conditional logistic regression model to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for prostate cancer with respect to levels of 25-hydroxy vitamin D (25(OH)D) in plasma.Results:We did not observe statistically significant association between 25(OH)D level and total prostate cancer (multivariate OR=1.13 (95%CI=0.66–1.94, Ptrend=0.94) for the highest versus lowest tertile) However, 25(OH) levels were slightly positively associated with advanced cancer. The results remained substantially unchanged after stratification by intake of fish or calcium intake.Conclusions:25(OH)D level showed no association with overall prostate cancer among Japanese men in this large cohort.European Journal of Clinical Nutrition advance online publication, 19 October 2016; doi:10.1038/ejcn.2016.184. © 2016 Macmillan Publishers Limited, part of Springer Nature.
Hidaka A.,Epidemiology and Prevention Group |
Shimazu T.,Epidemiology and Prevention Group |
Sawada N.,Epidemiology and Prevention Group |
Yamaji T.,Epidemiology and Prevention Group |
And 5 more authors.
American Journal of Clinical Nutrition | Year: 2015
Background: Most previous prospective studies inWestern countries found no association between consumption of fish and n-3 (v-3) polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA), for which the main source is fish, and pancreatic cancer risk. However, prospective evidence is still lacking among populations who have a relatively higher fish consumption. Objective: We investigated the association between fish and n-3 PUFA consumption and pancreatic cancer risk in a populationbased, prospective study in Japanese men and women. Design: The Japan Public Health Center-based Prospective Study (JPHC study) has enrolled 140,420 subjects. We analyzed data on 82,024 eligible participants aged 45-74 y without a history of cancer who responded to a validated food-frequency questionnaire that included 138 items in 1995 for cohort I and in 1998 for cohort II. Participants were followed through 2010. HRs and corresponding 95% CIs for the highest compared with lowest quartile were calculated by using multivariable-adjusted Cox proportional hazards regression models. Results: During 1,068,774 person-years of follow-up, 449 newly diagnosed pancreatic cancers were identified. After the exclusion of pancreatic cancer cases in the first 3 y of follow-up, we found an inverse association of marine n-3 PUFA (EPA+DPA+DHA) and DHA consumption with pancreatic cancer risk: compared with the lowest quartile, multivariate-adjusted HRs in the highest quartile were 0.70 (95% CI: 0.51, 0.95; P-trend = 0.07) and 0.69 (0.51, 0.94; P-trend = 0.03), respectively. Associations for total fish, n-3 PUFA, EPA, and DPA consumption were similar but were not significant. Conclusion: High n-3 PUFA, especially marine n-3 PUFAs, and DHA consumption was associated with a lower risk of pancreatic cancer in a population with a large variation in fish consumption, although the data apply to only a portion of the JPHC study subjects. © 2015 American Society for Nutrition.
PubMed | Epidemiology and Prevention Group
Type: Journal Article | Journal: European journal of clinical nutrition | Year: 2016
Although vitamin D has been experimentally reported to inhibit tumorigenesis, cell growth and prostate cancer invasion, epidemiologic data regarding prostate cancer risk are inconsistent, and some studies have suggested positive but nonsignificant associations. Further, the impact of vitamin D on prostate cancer between Western and Japanese populations may differ due to different plasma vitamin D levels.We performed a nested case-control study within the Japan Public Health Center-based Prospective (JPHC) Study in 14,203 men (40-69 years) who answered a self-administered questionnaire at baseline (1990-1994) and gave blood samples, and were followed until 2005. We identified 201 prostate cancers which are newly diagnosed during follow-up (mean 12.8 years). We selected two matched controls for each case from the cohort. We used a conditional logistic regression model to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for prostate cancer with respect to levels of 25-hydroxy vitamin D (25(OH)D) in plasma.We did not observe statistically significant association between 25(OH)D level and total prostate cancer (multivariate OR=1.13 (95%CI=0.66-1.94, P25(OH)D level showed no association with overall prostate cancer among Japanese men in this large cohort.
PubMed | National Center for Global Health and Medicine, Epidemiology and Prevention Group, Diabetes Research Center and University of Tokyo
Type: Journal Article | Journal: International journal of cancer | Year: 2016
Previous studies have reported associations between diabetes and cancer risk. However, specific association of hemoglobin A1c (HbA1c) levels with cancer risk remains inconclusive. We followed 29,629 individuals (11,336 men; 18,293 women) aged 46-80 years who participated in the Japan Public Health Center-based prospective study who had HbA1c measurements available and were cancer-free at baseline. Cancer incidence was assessed by systemic surveys. We estimated hazard ratios (HRs) for cancer risk with adjustment for age sex, geographic area, body mass index, smoking status, physical activity, alcohol, coffee, vegetable and total energy consumption, and history of cardiovascular disease. After a median follow-up of 8.5 years, 1,955 individuals had developed cancer. Higher HbA1c levels within both the non-diabetic and diabetic ranges in individuals without known diabetes were associated with overall cancer risk. Compared with individuals without known diabetes and HbA1c levels of 5.0-5.4%, the HRs for all cancers were 1.27 (95% confidence interval, 1.07-1.52); 1.01 (0.90-1.14); 1.28 (1.09-1.49); and 1.43 (1.14-1.80) for individuals without known diabetes and HbA1c levels <5.0%, 5.5-5.9%, 6.0-6.4%, and 6.5%, respectively, and 1.23 (1.02-1.47) for individuals with known diabetes. The lowest HbA1c group had the highest risk of liver cancer, and HbA1c levels were linearly associated with the risk of all cancers after excluding liver cancer (P for linear trend, 0.004). In conclusion, our findings corroborate the notion that glycemic control in individuals with high HbA1c levels may be important not only to prevent diabetes but also to prevent cancer.