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.

Predictive performance of a genetic risk score using 11 susceptibility alleles for the incidence of Type 2 diabetes in a general Japanese population: a nested case-control study.

AIMS: To assess the predictive ability of a genetic risk score for the incidence of Type 2 diabetes in a general Japanese population. METHODS: This prospective case-control study, nested within a Japan Public Health Centre-based prospective study, included 466 participants with incident Type 2 diabetes over a 5-year period (cases) and 1361 control participants, as well as 1463 participants with existing diabetes and 1463 control participants. Eleven susceptibility single nucleotide polymorphisms, identified through genome-wide association studies and replicated in Japanese populations, were analysed. RESULTS: Most single nucleotide polymorphism loci showed directionally consistent associations with diabetes. From the combined samples, one single nucleotide polymorphism (rs2206734 at CDKAL1) reached a genome-wide significance level (odds ratio 1.28, 95% CI 1.18-1.40; P = 1.8 × 10-8 ). Three single nucleotide polymorphisms (rs2206734 in CDKAL1, rs2383208 in CDKN2A/B, and rs2237892 in KCNQ1) were nominally significantly associated with incident diabetes. Compared with the lowest quintile of the total number of risk alleles, the highest quintile had a higher odds of incident diabetes (odds ratio 2.34, 95% CI 1.59-3.46) after adjusting for conventional risk factors such as age, sex and BMI. The addition to the conventional risk factor-based model of a genetic risk score using the 11 single nucleotide polymorphisms significantly improved predictive performance; the c-statistic increased by 0.021, net reclassification improved by 6.2%, and integrated discrimination improved by 0.003. CONCLUSIONS: Our prospective findings suggest that the addition of a genetic risk score may provide modest but significant incremental predictive performance beyond that of the conventional risk factor-based model without biochemical markers.

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.

Risk of haemolytic uraemic syndrome caused by shiga-toxin-producing Escherichia coli infection in adult women in Japan.

Shiga-toxin-producing Escherichia coli (STEC) infections usually cause haemolytic uraemic syndrome (HUS) equally in male and female children. This study investigated the localization of globotriaosylceramide (Gb3) in human brain and kidney tissues removed from forensic autopsy cases in Japan. A fatal case was used as a positive control in an outbreak of diarrhoeal disease caused by STEC O157:H7 in a kindergarten in Urawa in 1990. Positive immunodetection of Gb3 was significantly more frequent in female than in male distal and collecting renal tubules. To correlate this finding with a clinical outcome, a retrospective analysis of the predictors of renal failure in the 162 patients of two outbreaks in Japan was performed: one in Tochigi in 2002 and the other in Kagawa Prefecture in 2005. This study concludes renal failure, including HUS, was significantly associated with female sex, and the odds ratio was 4·06 compared to male patients in the two outbreaks. From 2006 to 2009 in Japan, the risk factor of HUS associated with STEC infection was analysed. The number of males and females and the proportion of females who developed HUS were calculated by age and year from 2006 to 2009. In 2006, 2007 and 2009 in adults aged >20 years, adult women were significantly more at risk of developing HUS in Japan.

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.

Short sleep duration in association with CT-scanned abdominal fat areas: the Hitachi Health Study.

OBJECTIVE: To examine the relationship between short sleep duration and body mass index (BMI), waist circumference (WC), visceral fat area (VFA) and subcutaneous fat area (SFA) among a working population in Japan. DESIGN: Health-center-based, cross-sectional study. SUBJECTS: The study subjects included 5400 men and 642 women aged 30 to 75 years who underwent an abdominal computed tomography (CT) scanning examination in a comprehensive health checkup. MEASUREMENTS: Height and weight were measured, and BMI was calculated. WC, VFA and SFA were measured using a CT scanner. Sleep duration was self-reported. Analysis of covariance was used to estimate adjusted means of BMI, WC, VFA and SFA across categories of sleep duration with adjustments for potential confounders. Trend of the association was assessed using multiple linear regression analysis. RESULTS: In men, the mean values of BMI, WC and SFA decreased with increasing sleep duration after adjustment for age, physical activity, smoking and drinking (P-value for trend <0.001). Additional adjustment for physical illnesses did not attenuate the explanatory power of the models (P-value for trend <0.001). In addition, the association between sleep duration and SFA did not change after controlling for VFA (P-value for trend <0.001). The mean values of SFA for subjects sleeping '<5 h', '5 to <6 h', '6 to <7 h' and '7 h' per day were 145.8±67.4 cm(2), 138.7±61.5 cm(2), 134.7±60.4 cm(2) and 132.5±49.2 cm(2), respectively. Sleep duration was not appreciably associated with VFA. In women, no significant association was detected in any models. CONCLUSION: Shorter sleep duration is associated with higher BMI, WC and SFA in men. Further research is needed to explicate the biological mechanisms behind these relationships and to see whether interventions addressing inadequate sleep could treat or prevent obesity by taking gender differences into consideration.

Comparison of risk factors for SARS-CoV-2 infection among healthcare workers during Omicron and Delta dominance periods in Japan.

BACKGROUND: The risk factors for coronavirus disease (COVID-19) among healthcare workers (HCWs) might have changed since the emergence of the highly immune evasive Omicron variant. AIM: To compare the risk factors for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among HCWs during the Delta- and Omicron-predominant periods. METHODS: Using data from repeated serosurveys among the staff of a medical research centre in Tokyo, two cohorts were established: Delta period cohort (N = 858) and Omicron period cohort (N = 652). The potential risk factors were assessed using a questionnaire. Acute/current or past SARS-CoV-2 infection was identified by polymerase chain reaction or anti-nucleocapsid antibody tests, respectively. Poisson regression was used to calculate the risk ratio (RR) of infection risk. FINDINGS: The risk of SARS-CoV-2 infection during the early Omicron-predominant period was 3.4-fold higher than during the Delta-predominant period. Neither working in a COVID-19-related department nor having a higher degree of occupational exposure to SARS-CoV-2 was associated with an increased infection risk during both periods. During the Omicron-predominant period, infection risk was higher among those who spent ≥30 min in closed spaces, crowded spaces, and close-contact settings without wearing mask (≥3 times versus never: RR: 6.62; 95% confidence interval: 3.01-14.58), whereas no such association was found during the Delta period. CONCLUSION: Occupational exposure to COVID-19-related work was not associated with the risk of SARS-CoV-2 infection in the Delta or Omicron period, whereas high-risk behaviours were associated with an increased infection risk during the Omicron period.

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.

Weight change and all-cause, cancer and cardiovascular disease mortality in Japanese men and women: the Japan Public Health Center-Based Prospective Study.

BACKGROUND: It is unclear whether weight change during adulthood influences subsequent mortality in Asian populations, who have a relatively lean body mass. OBJECTIVE: To assess the relation of weight change over 5 years to all-cause, cancer and cardiovascular disease mortality among Japanese men and women. DESIGN: Subjects were 36 220 men and 44 091 women aged between 45 and 75 years without a history of serious disease at baseline. Weight change was calculated as the difference of body weight between two surveys with a 5-year interval. RESULTS: During 699 963 person-years of follow-up, we identified 4232 deaths of all-cause, 1872 cancer deaths and 1021 cardiovascular deaths. The relation between weight change and all-cause mortality was reverse J-shaped. Multivariate hazard ratios (95% confidence interval) for weight loss of 5 kg or more versus weight change of less than 2.5 kg were 1.62 (1.45-1.81) in men and 1.76 (1.51-2.05) in women, whereas those for weight gain of 5 kg or more were 1.40 (1.22-1.59) in men and 1.25 (1.02-1.54) in women. These associations remained statistically significant even after the exclusion of deaths in the first 3 years of follow-up. The weight change-mortality association was pronounced in underweight persons or in nonsmoking men. The risk of cancer mortality increased in both men and women who lost weight by 5 kg or more. With regard to cardiovascular disease, mortality risk tended to increase with weight loss both in men and women, whereas its increase with weight gain was observed only in women. CONCLUSIONS: A large weight change, both loss and gain, was associated with an increased risk of mortality. Weight loss and gain may be predictors of early death in apparently healthy adult Japanese.

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.

Calcium, vitamin D and dairy intake in relation to type 2 diabetes risk in a Japanese cohort.

AIMS/HYPOTHESIS: Calcium and vitamin D have been implicated in the development of type 2 diabetes, but epidemiological evidence is limited. We examined prospectively the relation of calcium and vitamin D intake to type 2 diabetes risk in a Japanese cohort. METHODS: Participants were 59,796 middle-aged and older men and women, who participated in the Japan Public Health Center-based Prospective Study and had no history of type 2 diabetes or other serious diseases. Dietary intake of calcium and vitamin D were estimated using a validated food frequency questionnaire. Logistic regression was used to assess the association between intake of these nutrients and self-reported newly diagnosed type 2 diabetes. RESULTS: During a 5 year follow-up, 1,114 cases of type 2 diabetes were documented. Overall, calcium intake was not associated with a significantly lower risk of type 2 diabetes; the multivariable odds ratio for the highest vs lowest quartiles was 0.93 (95% CI 0.71-1.22) in men and 0.76 (95% CI 0.56-1.03) in women. However, among participants with a higher vitamin D intake, calcium intake was inversely associated with diabetes risk; the odds ratio for the highest vs lowest intake categories was 0.62 (95% CI 0.41-0.94) in men and 0.59 (95% CI 0.38-0.91) in women. Dairy food intake was significantly associated with a lower risk of type 2 diabetes in women only. CONCLUSIONS/INTERPRETATION: Calcium and vitamin D may not be independently associated with type 2 diabetes risk. Our finding suggesting a joint action of these nutrients against type 2 diabetes warrants further investigation.

Taste preferences and body weight change in Japanese adults: the JPHC Study.

OBJECTIVE: Limited data are available with regard to longitudinal changes in body weight by food taste preference. Here, we examined the associations between taste preferences and weight change in adults for a large-scale cohort study in Japan. DESIGN: Longitudinal analysis of data from a population-based cohort study, the Japan Public Health Center-based Prospective Study (JPHC Study). SUBJECTS: A total of 29,103 middle-aged men and women, who participated in a JPHC Study and returned questionnaires on lifestyle and diet, including taste preferences, at both baseline and the 10th year of follow-up. MEASUREMENTS: We assessed the relations of preferences for rich and heavy taste and a sweet taste to weight changes between the age of 20 years and baseline and those during the 10-year follow-up period. RESULTS: Preferences for rich and heavy taste and for sweet taste were significantly positively associated with weight increases between the age of 20 years and baseline (P for trend <0.001); the fully adjusted odds ratios (95% confidence interval) comparing the 'like' versus 'dislike' groups with a preference for rich and heavy taste were 1.45 (1.31-1.24) for men and 1.28 (1.16-1.41) for women, whereas that for a sweet taste preference was 1.22 (1.09-1.36) for women. As regards weight change during the 10 years of follow-up, subjects who liked the sweet taste and those who neither liked nor disliked this taste experienced a significantly greater increase than those who disliked it in both men and women. There was no such difference for rich and heavy taste. CONCLUSION: These results suggest that food taste preferences may be an important predictor of weight changes in adults. Taste preferences need to be considered when counseling patients to achieve weight control.

Overweight and obesity trends among Japanese adults: a 10-year follow-up of the JPHC Study.

OBJECTIVE: Limited data are available regarding longitudinal changes in body weight. Here, we describe changes in the prevalences of overweight and obesity and calculated the incidence of these indices during a 10-year follow-up period for a large-scale cohort study in Japan. DESIGN: Longitudinal analysis of data from a population-based cohort study, the Japan Public Health Center (JPHC) Study. PARTICIPANTS: A total of 65 095 Japanese men and women, who were between the ages of 40 and 69 years at baseline and participated in the 5th- and 10th-year follow-up surveys of the JPHC, were enroled in the study. MEASUREMENTS: Mean body mass index (BMI), calculated using self-reported height and weight, and the prevalences of overweight (BMI >or=25 kg/m(2)) and obesity (BMI >or=30 kg/m(2)) at each survey period. Incidences of overweight and obesity during the 10-year period. RESULTS: On an average, individuals living in Okinawa had much higher BMIs than those living on the Main islands for all sex and age groups. During the follow-up period, the prevalences of overweight and obesity steadily increased in the cohorts aged less than 50 years at baseline in both sexes. Men in younger cohorts had a higher mean BMI than those in the same age group of older cohorts, whereas the opposite trend was observed in women. The incidence of overweight individuals was greater in Okinawa than on the Main islands and among younger generations than among older ones. CONCLUSION: A longitudinal analysis at the individual level showed that the prevalences of overweight and obesity increased among middle-aged Japanese participants during the follow-up period. Among men, an increasing prevalence of obesity was observed among the younger generations. These findings should be taken into consideration when planning preventive strategies for obesity and its related diseases.

Oral symptoms predict mortality: a prospective study in Japan.

Several studies have reported positive associations between oral infections and systemic diseases. The purpose of the present study was to evaluate the effects of oral symptoms on mortality from cardiovascular disease (CVD) and pneumonia. Using data from a cohort study in Japan, we analyzed 4,139 individuals aged 40-79 years. The baseline questionnaire included the following items related to oral symptoms: 'sensitive teeth', 'difficulty in chewing tough food substances', 'bleeding gums', and 'mouth feels sticky'. We used the Cox proportional hazard model to estimate hazard ratios (HRs) and 95% confidence intervals (95%CIs) for mortality, after adjustments for lifestyle, socio-economic factors, and history of diseases. Persons complaining that their 'mouth feels sticky' had a two-fold higher risk of pneumonia (HR = 2.1; 95%CI, 1.2-3.6), while those complaining of 'sensitive teeth' had a lower risk of CVD (HR = 0.4; 95%CI, 0.2-0.9). Some oral symptoms may be predictors of mortality from pneumonia and CVD.

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.

Development of a shortened Japanese version of the Oral Health Impact Profile (OHIP) for young and middle-aged adults.

OBJECTIVE: The aim of this paper is to develop a short version of the Japanese OHIP (OHIP-J) appropriate for use in young and middle-aged adults, and to evaluate its properties using cross-sectional data. METHOD: A study population of 8,658 workers aged 20-59 years rated their oral health by means of a self-administered questionnaire. Using a factor analysis approach, a shortened version of OHIP-J was derived. Internal consistency, floor effect, and construct validity were determined. RESULTS: We derived a subset of 18 items from OHIP-J (OHIP-JA18), grouped into four subscales: "functional limitation", "physical pain", "psychological discomfort", and "disability & handicap". All four subscales had acceptable internal consistency (Cronbach alpha > 0.79). OHIP-JA18 demonstrated an acceptable floor effect, which was determined by the proportion of subjects who obtained a 0 score (< 30%); however, the floor effect of the ordinary shortened version based on OHIP-14 (OHIP-J14) was not acceptable. We confirmed the conceptual framework of OHIP-JA18 that "disability & handicap" is affected by "functional limitation", "physical pain" and "psychological discomfort", because the model fitted the data moderately well by structural equation modeling (SEM) analysis (GFI = 0.90, RMSEA = 0.08). CONCLUSIONS: OHIP-JA18 demonstrated acceptable measurement parameters to justify its use in outcome assessment for oral health related quality of life (OHQOL) in young and middle-aged adults in Japanese workers. Further studies will be needed to evaluate an intervention such as worksite health promotion.

Association of adulthood weight gain with circulating adipokine and insulin resistance in the Japanese population.

BACKGROUND/OBJECTIVES: Although adipokines and insulin resistance are known to be correlated with body fatness, it is unclear whether they are independently related to weight gain experience. We examined the associations of serum adipokines and marker of insulin resistance with past weight gain during adulthood by taking the degree of attained body mass index (BMI) level into consideration. SUBJECTS/METHODS: Subjects were 399 Japanese municipal employees, aged ⩾ 30 years, who participated in a health survey. Serum adipokines were measured using a Luminex suspension bead-based multiplexed array. Weight change during adulthood was calculated as the difference between measured current weight and recalled weight at the age of 20 years. Multiple regression was performed to calculate mean adipokine levels and homeostasis model assessment of insulin resistance (HOMA-IR) according to weight gain (< 5 kg, 5-9.9 kg, or ⩾ 10 kg) with adjustment for current BMI. RESULTS: Weight gain from the age of 20 years was significantly and positively associated with leptin levels even after adjustment for current BMI (P for trend < 0.001), whereas it was significantly and inversely associated with adiponectin levels in a BMI-adjusted model among subjects aged ⩾ 40 years (P for trend=0.03). Weight gain was associated with HOMA-IR in a BMI-unadjusted model (P for trend < 0.001), but this association was largely attenuated after adjustment for BMI. Resistin, plasminogen activator inhibitor-1 and visfatin were not associated with past weight gain. CONCLUSIONS: Results suggest that a large weight gain during adulthood is associated with higher leptin and lower adiponectin levels independently of the degree of attained BMI level.

p53 mutations of lung cancer are not significantly affected by CYP1A1 or GSTM1 polymorphisms.

Cytochrome p4501A1 gene (CYP1A1) and glutathione S-transferase mu gene (GSTM1) are involved in the metabolic activation or detoxification of environmental carcinogens including benzo[a]pyrene in tobacco smoke. Individuals with both Val/Val and C type of CYP1A1 (CYP1A1; Val/Val and CYP1A1; C) or homozygous null (-/-) genotype of GSTM1 gene (GSTM1; -/-) show increased susceptibility to lung cancer. The incidence of p53 gene mutations are related to the smoking index of the lung cancer patients. Therefore we determined genotypes of these enzymes and screened p53 gene mutations in 123 non-small cell lung cancer (NSCLC) patients. p53 gene mutations were found in 35% (43/123) of the patients. The incidence of p53 gene mutation CYP1A1; Val/Val (60.0%), CYP1A1; C (50.0%) tended to be higher than those of CYPIAI; Ile/Ile and Ile/Val (40.4%) or CYP1A1; A and B (40.5%). We conclude that the incidence of the p53 mutations does not seem to be significantly affected by only CYP1A1 or GSTM1 polymorphisms in lung cancer patients.