Cigarette smoking and cervical cancer risk: an evaluation based on a systematic review and meta-analysis among Japanese women.

BACKGROUND: There is a body of evidence to suggest that cigarette smoking increases the risk of cervical cancer in women, but no study has examined the magnitude of the association in Japanese women. Here, we evaluated the association between cigarette smoking and the risk of cervical cancer in Japanese women based on a systematic review of epidemiological evidence. METHODS: Original data were obtained from a MEDLINE search using PubMed or from a search of the 'Ichushi' database, as well as by a manual search. Evaluation of associations was based on the strength of evidence and the magnitude of association, together with biological plausibility as evaluated previously by the International Agency for Research on Cancer. Meta-analysis of associations was also conducted to obtain a summarized overview of the data. RESULTS: We identified two cohort studies and three case-control studies. All five studies had indicated strong positive associations between cigarette smoking and the risk of cervical cancer. Our summary estimate indicated that the relative risk (RR) for individuals who had ever-smoked relative to never-smokers was 2.03 (95% confidence interval: 1.49-2.57). Four studies had also demonstrated dose-response relationships between cigarette smoking and the risk of cervical cancer. CONCLUSION: We conclude that there is convincing evidence that cigarette smoking increases the risk of cervical cancer among Japanese women.

Evidence-based cancer prevention recommendations for Japanese.

A comprehensive evidence-based cancer prevention recommendation for Japanese was developed. We evaluated the magnitude of the associations of lifestyle factors and infection with cancer through a systematic review of the literature, meta-analysis of published data, and pooled analysis of cohort studies in Japan. Then, we judged the strength of evidence based on the consistency of the associations between exposure and cancer and biological plausibility. Important factors were extracted and summarized as an evidence-based, current cancer prevention recommendation: 'Cancer Prevention Recommendation for Japanese'. The recommendation addresses six important domains related to exposure and cancer, including smoking, alcohol drinking, diet, physical activity, body weight and infection. The next step should focus on the development of effective behavior modification programs and their implementation and dissemination.

Resultados de una revisión sistemática sobre la influencia de las largas jornadas de trabajo en la salud de los trabajadores / The association between long working hours and health: a systematic review of epidemiological evidence

Objetivo: Sintetizar la evidencia epidemiológica disponible sobre la asociación entre largas jornadas de trabajo y la salud, teniendo en cuenta las diferentes definiciones de largas jornadas de trabajo y el efecto de trabajo a turnos. Métodos: Se definió 'largas jornadas de trabajo' como el tiempo de trabajo mayor de 40 horas a la semana u 8 horas por día. Debido a que estudios previos han sugerido que el trabajo por turnos es perjudicial para la salud, se excluyeron de esta revisión aquellos estudios donde se incluía trabajadores por turnos para evitar el efecto que esta variable podía tener en la asociación. Además, se prestó especial atención a la existencia de grupos de referencia o control. Se establecieron criterios de inclusión y se realizó una búsqueda sistemática de los artículos publicados entre 1995-2012 en las bases de datos Medline y PsycINFO. Resultados: Se identificaron un total de 17 artículos que corresponden a 19 estudios (12 estudios de cohorte prospectivos y 7 transversales). Las variables de resultado fueron mortalidad por cualquier causa, enfermedad circulatoria, diabetes mellitus, síndrome metabólico, estado depresivo, ansiedad, otros trastornos psicológicos, trastornos del sueño, de la función cognitiva y de comportamiento relacionados con la salud. La exposición a largas jornadas de trabajo tuvo efectos adversos significativos en la mayoría de trastornos sobre la salud analizados. Conclusión: Trabajar durante largas horas se asocia con un estado depresivo, ansiedad, trastornos del sueño, y enfermedad coronaria. Sin embargo, se necesitan más estudios que tengan en cuenta las variaciones en la definición de largas jornadas de trabajo y el trabajo por turnos

No disponible

Association of vegetable and fruit intake with gastric cancer risk among Japanese: a pooled analysis of four cohort studies.

BACKGROUND: Prospective evidence is inconsistent regarding the association between vegetable/fruit intake and the risk of gastric cancer. METHODS: In an analysis of original data from four population-based prospective cohort studies encompassing 191 232 participants, we used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) of gastric cancer incidence according to vegetable and fruit intake and conducted a meta-analysis of HRs derived from each study. RESULTS: During 2 094 428 person-years of follow-up, 2995 gastric cancer cases were identified. After adjustment for potential confounders, we found a marginally significant decrease in gastric cancer risk in relation to total vegetable intake but not total fruit intake: the multivariate-adjusted HR (95% CI; P for trend) for the highest versus the lowest quintile of total vegetable intake was 0.89 (0.77-1.03; P for trend = 0.13) among men and 0.83 (0.67-1.03; P for trend = 0.40) among women. For distal gastric cancer, the multivariate HR for the highest quintile of total vegetable intake was 0.78 (0.63-0.97; P for trend = 0.02) among men. CONCLUSIONS: This pooled analysis of data from large prospective studies in Japan suggests that vegetable intake reduces gastric cancer risk, especially the risk of distal gastric cancer among men.

Body mass index and breast cancer risk in Japan: a pooled analysis of eight population-based cohort studies.

BACKGROUND: A positive association between body mass index (BMI) and breast cancer risk among postmenopausal women has been reported, and a weak inverse association has been suggested among premenopausal women from studies in the Western population. The effects of BMI on breast cancer have remained unclear among the Asian population, especially in premenopausal women. METHODS: We assessed the associations between BMI and breast cancer incidence by a pooled analysis from eight representative large-scale cohort studies in Japan. Cancer incidence was mainly confirmed through regional population-based cancer registries and/or through active patient notification from major local hospitals. Breast cancer was defined as code C50 according to ICD10. Pooled estimates of the hazard ratios (HRs) and 95% confidence interval (CIs) for breast cancer were calculated using random-effects models. RESULTS: Analytic subjects were 183 940 women, 1783 of whom had breast cancer during 2 194 211 person-years of follow-up. A positive association between BMI and the risk of postmenopausal breast cancer was observed (trend P<0.001). The HRs for premenopausal breast cancer were 1.05 (95% CI 0.56-1.99), 1.07 (95% CI 0.76-1.52), 0.91 (95% CI 0.64-1.30), 1.15 (95% CI 0.76-1.73), 1.45 (95% CI 0.71-2.94), and 2.25 (95% CI 1.10-4.60), respectively, in BMIs of <19, 19 to <21, 21 to <23, 25 to <27, 27 to <30, and ≥30 kg/m2. These results were not substantially altered after excluding the patients who were diagnosed with breast cancer in the first 2 years of follow-up. CONCLUSIONS: The increased risk of postmenopausal breast cancer among women with higher BMIs was confirmed in Japanese. A borderline-significant positive association between BMI and premenopausal breast cancer was observed, suggesting that body mass in Asian women might have opposite effects on breast cancer compared with Western women.

PBSC collection from family donors in Japan: a prospective survey.

Severe adverse events (SAE) and late hematological malignancies have been reported after PBSC donation. No prospective data on incidence and risk factors have been available for family donors so far. The Japan Society for Hematopoietic Cell Transplantation (JSHCT) introduced therefore in 2000 a mandatory registration system. It defined standards for donor eligibility and asked harvest centers to report any SAE immediately. All donors were examined at day 30 and were to be contacted once each year for a period of 5 years. Acute SAEs within day 30 were reported from 47/3264 donations (1.44%) with 14 events considered as unexpected and severe (0.58%). No donor died within 30 days. Late SAEs were reported from 39/1708 donors (2.3%). The incidence of acute SAEs was significantly higher among donors not matching the JSHCT standards (P=0.0023). Late hematological malignancies in PBSC donors were not different compared with a retrospective cohort of BM donors (N:1/1708 vs N:2/5921; P=0.53). In conclusion, acute and late SAEs do occur in PBSC donors at relatively low frequency but risk factors can be defined.

Relationship between vegetable and carotene intake and risk of prostate cancer: the JACC study.

BACKGROUND: We examined the associations of intakes of vegetables and carotenes with risk of prostate cancer in Japanese. METHODS: A total of 15,471 Japanese men participating in the Japan Collaborative Cohort study completed a questionnaire including food intake. Of them, 143 incident prostate cancers were documented. We examined the associations stated above by using Cox proportional hazard model. RESULTS: Vegetable intake was not associated with the risk of prostate cancer, but so was dietary alpha-carotene intake. The multivariable hazard ratio (95%CI) in the secondary highest and highest quintiles of alpha-carotene intake was 0.50 (0.26-0.98) (P=0.043) and 0.46 (0.22-0.97) (P=0.041) (P for trend=0.224), respectively. Beta-carotene intake was not associated with the risk of prostate cancer. CONCLUSION: Alpha-carotene intake was associated with lower risk of prostate cancer among Japanese.

Dietary patterns and risk of cardiovascular deaths among middle-aged Japanese: JACC Study.

BACKGROUND AND AIMS: Little evidence showed the association between dietary patterns and cardiovascular disease among Japanese. The objective of this study was to examine whether dietary patterns are associated with cardiovascular disease among middle-aged Japanese. METHODS AND RESULTS: At baseline (1988-1990), 26,598 men and 37,439 women aged 40-79 years enrolled in the Japan Collaborative Cohort (JACC) Study. During the follow-up through 2003, 578 men and 499 women died from stroke, and 272 men and 207 women died from coronary heart disease. We identified three major dietary patterns, 'vegetable', 'animal food' and 'dairy product', by factor analysis for both sexes. The multivariable hazard ratio (HR) and 95% confidence intervals of mortality from total cardiovascular disease in the highest versus lowest quintiles of the vegetable pattern were 0.93 (0.78-1.13), p for trend=0.73 for men and 0.82 (0.67-1.00), p for trend=0.04 for women. The respective HRs of mortality from stroke in the highest versus lowest quintiles of the dairy product pattern were 0.65 (0.49-0.86), p for trend=0.01 for men and 0.70 (0.51-0.97), p for trend=0.02 for women, and those of total cardiovascular disease were 0.89 (0.74-1.08), p for trend=0.23 for men and 0.76 (0.61-0.94), p for trend=0.01 for women. The animal food pattern was not associated with mortality from stroke, coronary heart disease or total cardiovascular disease for either sex. CONCLUSION: We found that 'vegetable' and 'dairy product' patterns were associated with lower morality from cardiovascular disease, while the 'animal food' pattern was not associated with mortality from cardiovascular disease among Japanese.

Meat consumption in relation to mortality from cardiovascular disease among Japanese men and women.

BACKGROUND/OBJECTIVES: Although high or low (no) meat consumption was associated with elevated or reduced mortality from cardiovascular disease, respectively, few studies have investigated the association between moderate meat consumption and cardiovascular disease. We aimed to evaluate the associations between moderate meat consumption and cardiovascular disease mortality. SUBJECTS/METHODS: We conducted a prospective cohort study of 51,683 Japanese (20,466 men and 31,217 women) aged 40-79 years living in all of Japan (The Japan Collaborative Cohort Study; JACC Study). Consumptions of meat (beef, pork, poultry, liver and processed meat) were assessed via a food frequency questionnaire administrated at baseline survey. Hazard ratios (HRs) of mortality from cardiovascular disease were estimated from Cox proportional hazards regression models according to quintiles of meat consumption after adjustment for potential confounding variables. RESULTS: During 820,076 person-years of follow-up, we documented 2685 deaths due to total cardiovascular disease including 537 ischemic heart diseases and 1209 strokes. The multivariable HRs (95% confidence interval) for the highest versus lowest quintiles of meat consumption (77.6 versus 10.4 g/day) among men were 0.66 (0.45-0.97) for ischemic heart disease, 1.10 (0.84-1.43) for stroke and 1.00 (0.84-1.20) for total cardiovascular disease. The corresponding HRs (59.9 versus 7.5 g/day) among women were 1.22 (0.81-1.83), 0.91 (0.70-1.19) and 1.07 (0.90-1.28). The associations were similar when the consumptions of red meat, poultry, processed meat and liver were examined separately. CONCLUSION: Moderate meat consumption, up to ~100 g/day, was not associated with increased mortality from ischemic heart disease, stroke or total cardiovascular disease among either gender.

Association between body mass index and the colorectal cancer risk in Japan: pooled analysis of population-based cohort studies in Japan.

BACKGROUND: Obesity has been recognized as important risk factors for colorectal cancer. However, limited evidence is available on colorectal cancer and body mass index (BMI) in Asian population. METHODS: We conducted a pooled analysis of eight population-based prospective cohorts studies in Japan with more than 300,000 subjects to evaluate an impact of obesity in terms of BMI on colorectal cancer risk with unified categories. We estimated summary hazard ratio (HR) by pooling of study-specific HR for BMI categories with random effect model. RESULTS: We found a significant positive association between BMI and colorectal cancer risk in male and female. Adjusted HRs for 1 kg/m(2) increase were 1.03 [95% confidence interval (CI) 1.02-1.04] for males and 1.02 (95% CI 1.00-1.03) for females. The association was stronger in colon, especially in proximal colon, relative to rectum. Males showed a stronger association than females. Population attributable fraction for colorectal cancer by BMI ≥ 25 kg/m(2) was 3.62% (95% CI 1.91-5.30) for males and 2.62% (95% CI 0.74-4.47) for females. CONCLUSIONS: We found significant association between BMI and colorectal cancer risk by pooling of data from cohort studies with considerable number of subjects among Japanese population. This information is important in cancer control planning, especially in Asian population.

Associations of diabetes mellitus with site-specific cancer mortality in the Asia-Pacific region.

BACKGROUND: Owing to the increasing prevalence of obesity and diabetes in Asia, and the paucity of studies, we examined the influence of raised blood glucose and diabetes on cancer mortality risk. MATERIALS AND METHODS: Thirty-six cohort Asian and Australasian studies provided 367, 361 participants (74% from Asia); 6% had diabetes at baseline. Associations between diabetes and site-specific cancer mortality were estimated using time-dependent Cox models, stratified by study and sex, and adjusted for age. RESULTS: During a median follow-up of 4.0 years, there were 5992 deaths due to cancer (74% Asian; 41% female). Participants with diabetes had 23% greater risk of mortality from all-cause cancer compared with those without: hazard ratio (HR) 1.23 [95% confidence interval (CI) 1.12, 1.35]. Diabetes was associated with mortality due to cancer of the liver (HR 1.51; 95% CI 1.19, 1.91), pancreas (HR 1.78; 95% CI 1.20, 2.65), and, less strongly, colorectum (HR 1.32; 95% CI 0.98, 1.78). There was no evidence of sex- or region-specific differences in these associations. The population attributable fractions for cancer mortality due to diabetes were generally higher for Asia compared with non-Asian populations. CONCLUSION: Diabetes is associated with increased mortality from selected cancers in Asian and non-Asian populations.

Green tea consumption and gastric cancer in Japanese: a pooled analysis of six cohort studies.

BACKGROUND: Previous experimental studies have suggested many possible anti-cancer mechanisms for green tea, but epidemiological evidence for the effect of green tea consumption on gastric cancer risk is conflicting. OBJECTIVE: To examine the association between green tea consumption and gastric cancer. METHODS: We analysed original data from six cohort studies that measured green tea consumption using validated questionnaires at baseline. Hazard ratios (HRs) in the individual studies were calculated, with adjustment for a common set of variables, and combined using a random-effects model. RESULTS: During 2 285 968 person-years of follow-up for a total of 219 080 subjects, 3577 cases of gastric cancer were identified. Compared with those drinking <1 cup/day, no significant risk reduction for gastric cancer was observed with increased green tea consumption in men, even in stratified analyses by smoking status and subsite. In women, however, a significantly decreased risk was observed for those with consumption of > or =5 cups/day (multivariate-adjusted pooled HR = 0.79, 95% confidence interval (CI) = 0.65 to 0.96). This decrease was also significant for the distal subsite (HR = 0.70, 95% CI = 0.50 to 0.96). In contrast, a lack of association for proximal gastric cancer was consistently seen in both men and women. CONCLUSIONS: Green tea may decrease the risk of distal gastric cancer in women.

Cigarette smoking, alcohol drinking, and oral and pharyngeal cancer mortality in Japan.

OBJECTIVES: To prospectively examine the association of cigarette smoking and alcohol drinking with oral and pharyngeal carcinogenesis, we analyzed data from a nation-wide large-scale cohort study in Japan. METHODS: A total of 34 136 men and 43 711 women aged 40-79 years were included in the study. The Cox proportional hazard model was used to estimate the relative risk (RR) and 95% confidence interval (95% CI) of oral and pharyngeal cancer for smoking and drinking by sex, while adjusting for age, consumption of green tea, preference for salty foods, and consumption of green yellow vegetables. RESULTS: Current smokers were found to have a higher risk of death caused by oral and pharyngeal cancer compared with non-smokers in both sexes: the RR was 2.6 (95% CI: 1.0-6.7) in men and 8.2 (95% CI: 2.1-32.1) in women. Men who drank more than 46 g ethanol per day had an approximately threefold increased risk of oral and pharyngeal cancer. Simultaneous exposure to both factors was significantly associated with an elevated risk of oral and pharyngeal cancer (RR: 3.3, 95% CI: 1.1-9.6). CONCLUSIONS: The result supports the carcinogenic effect of cigarette smoking and alcohol drinking on the oral cavity and pharynx.

Prevalence and incidence rates of chronic inflammatory demyelinating polyneuropathy in the Japanese population.

OBJECTIVE AND METHODS: To characterise the epidemiological features of chronic inflammatory demyelinating polyneuropathy (CIDP) in the Japanese population, this study performed a nationwide assessment of the prevalence and incidence rates in Japan. RESULTS: The prevalence rate per 100 000 was 1.61 in the total population; 2.01 in males and 1.23 in females. The age dependent prevalence rates were 0.23 in juveniles (<15 years old), 1.50 in young adults (15-55 years) and 2.31 in elderly adults (>55 years). The sex and age dependent prevalence rates were 0.22 in males and 0.24 in females in juveniles, 1.81 in males and 1.19 in females in young adults, and 3.12 in males and 1.64 in females in elderly adults. The annual incidence rate per 100 000 was 0.48 in the total population, 0.58 in males and 0.38 in females. The age dependent incidence rate was 0.06 in juveniles, 0.40 in young adults and 0.73 in elderly adults. The sex and age dependent incidence rate was 0.05 in males and 0.08 in females in juveniles, 0.50 in males and 0.30 in females in young adults, and 0.93 in males and 0.58 in females in elderly adults. Both the prevalence and incidence rates were very similar throughout the eight geographical areas studied, from the northern to the southern parts of Japan. CONCLUSIONS: The prevalence and incidence rates were similar to those reported in the Caucasian population. The pathogenic background is suggested to be common throughout the different races and geographic areas, while gender and age effects should be taken into account in the pathogenesis of CIDP.

Smoking status, sports participation and mortality from coronary heart disease.

BACKGROUND: Since smoking and exercise have opposite effects on coronary risk factors, the hypothesis was proposed that smoking might weaken the protective effect of exercise on prevention of coronary heart disease. OBJECTIVE: To determine the effect of smoking on the relationship between sports participation and mortality from coronary heart disease. DESIGN: Population-based prospective cohort study in Japan. PARTICIPANTS: A total of 76 832 Japanese men and women, aged 40-79 years with no history of stroke, coronary heart disease, or cancer, completed a self-administered questionnaire between 1988 and 1990. MAIN OUTCOME MEASURES: Systematic mortality surveillance was carried out through 2003, and 638 deaths from coronary heart disease (496 myocardial infarction) were identified. RESULTS: People who reported the longest time in sports participation (>or=5 hours/week) had an approximately 50-80% lower age-adjusted risk of mortality from coronary heart disease compared with those in the second lowest category (1-2 hours/week) among never and ex-smokers, but no association was found among current smokers. Adjustment for known risk factors and exclusion of subjects who died within 2 years of the baseline inquiry did not substantially alter these associations. The multivariable hazard ratios (95% confidence interval) of coronary heart disease for the >or=5 hours/week versus 1-2 hours/week of sports participation were 0.44 (0.23 to 0.86) among never smokers, 0.18 (0.05 to 0.60) among ex-smokers, and 0.82 (0.47 to 1.40) among current smokers. Similar associations were found for men and women. CONCLUSIONS: Smoking may reduce the beneficial effect of sports participation for reduction of fatal coronary heart disease.

Liver cancer risk, coffee, and hepatitis C virus infection: a nested case-control study in Japan.

We examined hepatocellular carcinoma mortality in relation to coffee consumption and anti-hepatitis C virus (HCV) antibody seropositivity in a nested case-control study involving 96 cases. The multivariate-adjusted odds ratios (95% confidence interval) for daily coffee drinkers vs non-drinkers were 0.49 (0.25-0.96), 0.31 (0.11-0.85), and 0.75 (0.29-1.92) in all cases, in HCV-positive and in HCV-negative individuals, respectively.

The effect of interaction between hepatitis C virus and cigarette smoking on the risk of hepatocellular carcinoma.

We evaluated the interaction between hepatitis C virus (HCV) and cigarette smoking on death from hepatocellular cancer in The Japan Collaborative Cohort Study. The odds ratio of death from HCC for smoking was 9.60 (1.50-61.35) and 1.71(0.58-5.08) among anti-HCV positive and negative individuals, respectively.

Parental longevity and mortality amongst Japanese men and women: the JACC Study.

OBJECTIVES: To examine whether the risk of mortality varies according to parents' age at death. DESIGN AND SUBJECTS: A large prospective study in Japanese men and women from 45 communities across Japan. A total of 51 485 men and women aged 40-79 years completed self-administered questionnaires at baseline and followed up for 9.6 years. RESULTS: The risk of mortality from stroke, cardiovascular disease, and all causes was 20-30% lower in men and women with fathers who died at age > or = 80 years, compared with those with fathers whose age at death was <60 years. A similar reduction was found when the age at death of mothers was > or = 85 years compared with <65 years. Furthermore, the risk reduction was more evident amongst persons with both parents being long-lived parents compared with those with being short-lived parents, especially for death from cardiovascular disease. CONCLUSIONS: Our findings indicate that parental longevity could be a predictor for reduced risk of mortality from stroke, cardiovascular disease, and all causes for both Japanese men and women.

Coffee and risk of death from hepatocellular carcinoma in a large cohort study in Japan.

We examined the relation between coffee drinking and hepatocellular carcinoma (HCC) mortality in the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study). In total, 110,688 cohort members (46,399 male and 64,289 female subjects) aged 40-79 years were grouped by coffee intake into three categories: one or more cups per day, less than one cup per day and non-coffee drinkers. Cox proportional hazards model by SAS was used to obtain hazard ratio of HCC mortality for each coffee consumption categories. The hazard ratios were adjusted for age, gender, educational status, history of diabetes and liver diseases, smoking habits and alcohol. The hazard ratio of death due to HCC for drinkers of one and more cups of coffee per day, compared with non-coffee drinkers, was 0.50 (95% confidence interval 0.31-0.79), and the ratio for drinkers of less than one cup per day was 0.83 (95% confidence interval 0.54-1.25). Our data confirmed an inverse association between coffee consumption and HCC mortality.

Familial aggregation and coaggregation of history of hypertension and stroke.

We attempted to evaluate familial aggregation and coaggregation of history of hypertension and stroke. Past and family history of hypertension and stroke for 83 089 probands and their relatives were obtained from a data set for the Japan Collaborative Cohort Study for Evaluation of Cancer Risk sponsored by the Ministry of Education (JACC Study), which was initiated from 1988 to 1990. First, evaluation was performed for familial aggregation of each of two disorders using ordinal logistic regression of the generalized estimation equations (GEE) to account for dependence of observations within families. Secondly, in order to evaluate the familial congregation of the history of hypertension and stroke, a GEE-based multivariate probed predictive model was applied. After adjusting for the proband's age, level of obesity, smoking status, drinking status, habitation area, and the gender and type of the relatives, the estimated odds ratios for the intraindividual clustering and familial aggregation of the disease history showed statistically significant relationships. In addition, the history of the two disorders showed a significant relationship in terms of familial coaggregation independently of the aggregation of each disorder itself. Our results confirmed that hypertension and stroke coaggregate strongly within families through possible effects of genetic factors, which, alone or in conjunction with environmental factors, influence susceptibility to both hypertension and stroke.