Coffee and metabolic phenotypes: A cross-sectional analysis of the Japan multi-institutional collaborative cohort (J-MICC) study.

BACKGROUND AND AIMS: To date, the relationship between coffee consumption and metabolic phenotypes has hardly been investigated and remains controversial. Therefore, the aim of this cross-sectional study is to examine the associations between coffee consumption and metabolic phenotypes in a Japanese population. METHODS AND RESULTS: We analyzed the data of 26,363 subjects (aged 35-69 years) in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. Coffee consumption was assessed using a questionnaire. Metabolic Syndrome (MetS) was defined according to the Joint Interim Statement Criteria of 2009, using body mass index (BMI) instead of waist circumference. Subjects stratified by the presence or absence of obesity (normal weight: BMI <25 kg/m2; obesity: BMI ≥25 kg/m2) were classified by the number of MetS components (metabolically healthy: no components; metabolically unhealthy: one or more components) other than BMI. In multiple logistic regression analyses adjusted for sex, age, and other potential confounders, high coffee consumption (≥3 cups/day) was associated with a lower prevalence of MetS and metabolically unhealthy phenotypes both in normal weight (OR 0.83, 95% CI 0.76-0.90) and obese subjects (OR 0.83, 95% CI 0.69-0.99). Filtered/instant coffee consumption was inversely associated with the prevalence of MetS and metabolically unhealthy phenotypes, whereas canned/bottled/packed coffee consumption was not. CONCLUSION: The present results suggest that high coffee consumption, particularly filtered/instant coffee, is inversely associated with the prevalence of metabolically unhealthy phenotypes in both normal weight and obese Japanese adults.

Epidemiological characteristics of rheumatoid arthritis in Japan: Prevalence estimates using a nationwide population-based questionnaire survey.

Objectives: To elucidate the epidemiological characteristics of patients with rheumatoid arthritis (RA) in Japan using data from the Comprehensive Survey of Living Conditions, a nationwide questionnaire survey conducted in 2016.Methods: In total, 222,365 men and 245,251 women aged ≥16 years were included in the study. RA patients were defined as those who reported 'currently receiving treatment for RA at hospitals, clinics, or a facility for Japanese traditional massage, acupuncture, moxibustion, or judo-orthopedics.' The number of RA patients was estimated from the age-specific prevalence and total Japanese population in 2016. Further, the prevalence of individuals experiencing difficulties in activities of daily living due to health problems and those with mental distress as evaluated by K6 Scale was examined.Results: The estimated number and prevalence of RA in Japan with 95% confidence interval was 822 (768-880) thousand and 0.75% (0.70-0.80%). The population peaked in the late 60s, and the prevalence continued increasing until the early 80s, regardless of sex. Compared with non-RA participants, RA patients were more likely to experience difficulties in activities and to be distressed.Conclusion: High prevalence of RA in older age and mental and physical burden among RA patients were confirmed.

Genome-wide association meta-analysis and Mendelian randomization analysis confirm the influence of ALDH2 on sleep durationin the Japanese population.

Usual sleep duration has substantial heritability and is associated with various physical and psychiatric conditions as well as mortality. However, for its genetic locus, only PAX8 and VRK2 have been replicated in previous genome-wide association studies (GWAS). We conducted a GWAS meta-analysis of self-reported usual sleep duration using three population-based cohorts totaling 31 230 Japanese individuals. A genome-wide significant locus was identified at 12q24 (p-value < 5.0 × 10-8). Subsequently, a functional variant in the ALDH2 locus, rs671, was replicated in an independent sample of 5140 Japanese individuals (p-value = 0.004). The association signal, however, disappeared after adjusting for alcohol consumption, indicating the possibility that the rs671 genotype modifies sleep duration via alcohol consumption. This hypothesis explained a modest genetic correlation observed between sleep duration and alcohol consumption (rG = 0.23). A Mendelian randomization analysis using rs671 and other variants as instrumental variables confirmed this by showing a causal effect of alcohol consumption, but not of coffee consumption on sleep duration. Another genome-wide significant locus was identified at 5q33 after adjusting for drinking frequency. However, this locus was not replicated, nor was the PAX8 and VRK2. Our study has confirmed that a functional ALDH2 variant, rs671, most strongly influences on usual sleep duration possibly via alcohol consumption in the Japanese population, and presumably in East Asian populations. This highlights the importance of considering the involvement of alcohol consumption in future GWAS of usual sleep duration, even in non-East Asian populations, where rs671 is monomorphic.

A genome-wide association study in the Japanese population identifies the 12q24 locus for habitual coffee consumption: The J-MICC Study.

Coffee is one of the most widely consumed beverages worldwide, and its role in human health has received much attention. Although genome-wide association studies (GWASs) have investigated genetic variants associated with coffee consumption in European populations, no such study has yet been conducted in an Asian population. Here, we conducted a GWAS to identify common genetic variations that affected coffee consumption in a Japanese population of 11,261 participants recruited as a part of the Japan Multi-Institutional Collaborative Cohort (J-MICC) study. Coffee consumption was collected using a self-administered questionnaire, and converted from categories to cups/day. In the discovery stage (n = 6,312), we found 2 independent loci (12q24.12-13 and 5q33.3) that met suggestive significance (P < 1 × 10-6). In the replication stage (n = 4,949), the lead variant for the 12q24.12-13 locus (rs2074356) was significantly associated with habitual coffee consumption (P = 2.2 × 10-6), whereas the lead variant for the 5q33.3 locus (rs1957553) was not (P = 0.53). A meta-analysis of the discovery and replication populations, and the combined analysis using all subjects, revealed that rs2074356 achieved genome-wide significance (P = 2.2 × 10-16 for a meta-analysis). These findings indicate that the 12q24.12-13 locus is associated with coffee consumption among a Japanese population.

Macronutrient intakes and serum oestrogen, and interaction with polymorphisms in CYP19A1 and HSD17B1 genes: a cross-sectional study in postmenopausal Japanese women.

Although higher circulating levels of oestrogen are related to postmenopausal breast cancer risk, limited information is available regarding effects of diet on endogenous oestrogen. Thus, we examined associations between macronutrient intakes and serum oestrogen with consideration of polymorphisms in oestrogen-metabolising genes. In this cross-sectional study, 784 naturally menopaused Japanese women aged 47-69 years were selected from participants of the Japan Multi-Institutional Collaborative Cohort Study. We documented dietary intakes, measured serum concentrations of oestrone (E1) and oestradiol (E2) and genotyped polymorphisms in oestrogen-metabolising CYP19A1 (rs4441215 and rs936306) and HSD17B1 (rs605059) genes. Trends and interactions were examined using linear regression models. In addition, we calculated the ratios of the oestrogen concentrations of the second to the highest quartiles (Q2-Q4) of dietary intake to those of the lowest quartiles (Q1). After adjustment for potential confounders, E2 was significantly associated with intake of carbohydrate and noodles; ratios of Q4 v. Q1 were 1·15 (95 % CI 1·04, 1·28) and 1·15 (95 % CI 1·04, 1·26), respectively. In contrast, E2 levels were inversely associated with intake of total energy, SFA and n-3 highly unsaturated fatty acids (n-3 HUFA); ratios of Q4 v. Q1 were 0·90 (95 % CI 0·82, 0·99), 0·89 (95 % CI 0·81, 0·98) and 0·91 (95 % CI 0·83, 1·00), respectively. In stratified analysis by polymorphisms, the rs605059 genotype of HSD17B1 significantly modified associations of E2 with intake of n-3 HUFA and fish; the associations were limited to those with the CC genotype. Macronutrient intakes were associated with serum E2 level, and these associations may be modified by HSD17B1 polymorphism in postmenopausal women.

Coffee consumption and risk of colorectal cancer: the Japan Collaborative Cohort Study.

BACKGROUND: Epidemiologic studies have reported coffee consumption to be associated with various health conditions. The purpose of this study was to examine the relationship of coffee consumption with colorectal cancer incidence in a large-scale prospective cohort study in Japan. METHODS: We used data from the Japan Collaborative Cohort Study for Evaluation of Cancer Risk (JACC Study). Here, we analyzed a total of 58 221 persons (23 607 men, 34 614 women) followed from 1988 to the end of 2009. During 738 669 person-years of follow-up for the analysis of colorectal cancer risk with coffee consumption at baseline, we identified 687 cases of colon cancer (355 males and 332 females) and 314 cases of rectal cancer (202 males and 112 females). We used the Cox proportional-hazard regression model to estimate hazard ratio (HR). RESULTS: Compared to those who consumed less than 1 cup of coffee per day, men who consumed 2-3 cups of coffee per day had an HR of 1.26 (95% confidence interval [CI] 0.93-1.70), and men who consumed more than 4 cups of coffee per day had an HR of 1.79 (95% CI 1.01-3.18). A statistically significant increase in the risk of colon cancer was associated with increasing coffee consumption among men (P for trend = 0.03). On the other hand, coffee consumption in women was not associated with incident risk of colon cancer. Coffee consumption was also not associated with rectal cancer incidence in men or women. CONCLUSIONS: This large-scale population-based cohort study showed that coffee consumption increases the risk of colon cancer among Japanese men.