Population-Based Impact of Smoking, Drinking, and Genetic Factors on HDL-cholesterol Levels in J-MICC Study Participants.

BACKGROUND: Environmental and genetic factors are suggested to exhibit factor-based association with HDL-cholesterol (HDL-C) levels. However, the population-based effects of environmental and genetic factors have not been compared clearly. We conducted a cross-sectional study using data from the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study to evaluate the population-based impact of smoking, drinking, and genetic factors on low HDL-C. METHODS: Data from 11,498 men and women aged 35-69 years were collected for a genome-wide association study (GWAS). Sixty-five HDL-C-related SNPs with genome-wide significance (P < 5 × 10-8) were selected from the GWAS catalog, of which seven representative SNPs were defined, and the population-based impact was estimated using population attributable fraction (PAF). RESULTS: We found that smoking, drinking, daily activity, habitual exercise, egg intake, BMI, age, sex, and the SNPs CETP rs3764261, APOA5 rs662799, LIPC rs1800588, LPL rs328, ABCA1 rs2575876, LIPG rs3786247, and APOE rs429358 were associated with HDL-C levels. The gene-environmental interactions on smoking and drinking were not statistically significant. The PAF for low HDL-C was the highest in men (63.2%) and in rs3764261 (31.5%) of the genetic factors, and the PAFs of smoking and drinking were 23.1% and 41.8%, respectively. CONCLUSION: The present study showed that the population-based impact of genomic factor CETP rs3764261 for low HDL-C was higher than that of smoking and lower than that of drinking.

Cumulative cigarette tar exposure and lung cancer risk among Japanese smokers.

OBJECTIVE: Tar concentration in cigarette brands is chronologically decreasing in the USA and Japan. However, studies investigating lung cancer risk with cumulative tar exposure in Western and Asian countries are insufficient. To investigate the risk of lung cancer with cumulative cigarette tar exposure, we conducted a case-control study among Japanese current smokers. METHODS: This study used data from the US-Japan lung cancer joint study in 1993-1998. A total of 282 subjects with histologically confirmed lung cancer and 162 hospital and 227 community controls were included in the study, and two control groups were combined. The information regarding tar concentration was obtained from the published documents and additional estimation using the equation of regression. Cumulative tar concentration was calculated by multiplying the annual value of brand-specific tar concentration by years of smoking. The odds ratios and 95% confidence intervals for lung cancer with cumulative tar exposure were estimated using a logistic model. RESULTS: The odds ratios for lung cancer with both lower (1-59.8 × 105 mg) and higher (>59.8 × 105 mg) total cumulative tar exposure were statistically significant (3.81, 2.23-6.50 and 11.64, 6.56-20.67, respectively) with increasing trend (P < 0.001). The stratification analysis showed higher odds ratios in subjects with higher cumulative tar exposure regardless of inhalation, duration of smoking filtered cigarettes and histological type. CONCLUSIONS: This study showed that cumulative tar exposure is a dose-dependent indicator for lung cancer risk, and low-tar exposure was still associated with increased cancer risk.

The association between clustering based on composition of volatile organic compound in indoor air and building-related symptoms.

Volatile organic compounds (VOCs) have been suspected to cause building-related symptoms (BRSs). Although some studies investigated the association between BRSs and VOCs in indoor air, those results were inconsistent. This study investigated the contamination status of VOCs in the indoor air of 154 houses in Japan. Additionally, these samples were grouped by hierarchical clustering analysis based on the VOC composition, and the relationship between a VOC cluster and the BRSs was investigated. The median concentration of the sum of VOCs (ΣVOCs) was 140 µg m-3 (range: 18-3500 µg m-3). The levels of acetaldehyde in four samples and p-dichlorobenzene in one sample exceeded the guideline value. As a result of the hierarchical clustering analysis, the samples in this study were divided into six characteristic clusters based on the VOC composition. The ΣVOCs in cluster 1 were significantly lower than those in other clusters. In cluster 2, acyclic and aromatic hydrocarbons were dominant. Cluster 3 had a relatively high proportion of limonene. In cluster 4, the concentrations and composition ratios of α-pinene were higher than those of other clusters. In cluster 5, p-dichlorobenzene accounted for 42 %-72 % of the total VOCs. Cluster 6 had a relatively high proportion of decamethyl cyclopentasiloxane. This clustering likely depended on the construction of houses and lifestyles. As a result of logistic regression analysis, cluster 5 was associated with the cough symptoms of the BRSs. The results of the present study suggest that investigating the association between VOCs and BRSs is necessary to consider not only total concentrations such as TVOC and ΣVOCs but also VOC composition.

Association of inflammatory gene polymorphisms and conventional risk factors with arterial stiffness by age.

BACKGROUND: Inflammatory gene polymorphisms are potentially associated with atherosclerosis risk, but their age-related effects are unclear. To investigate the age-related effects of inflammatory gene polymorphisms on arterial stiffness, we conducted cross-sectional and 5-year follow-up studies using the cardio-ankle vascular index (CAVI) as a surrogate marker of arterial stiffness. METHODS: We recruited 1850 adults aged 34 to 69 years from the Japanese general population. Inflammatory gene polymorphisms were selected from NF-kB1, CD14, IL-6, IL-10, MCP-1, ICAM-1, and TNF-α. Associations of CAVI with genetic and conventional risk factors were estimated by sex and age group (34-49, 50-59, and 60-69 years) using a general linear model. The association with 5-year change in CAVI was examined longitudinally. RESULTS: Glucose intolerance was associated with high CAVI among women in all age groups, while hypertension was associated with high CAVI among participants in all age groups, except younger women. Mean CAVI for the CD14 CC genotype was lower than those for the TT and CT genotypes (P for trend = 0.005), while the CD14 polymorphism was associated with CAVI only among men aged 34 to 49 years (P = 0.006). No association of the other 6 polymorphisms with CAVI was observed. No association with 5-year change in CAVI was apparent. CONCLUSIONS: Inflammatory gene polymorphisms were not associated with arterial stiffness. To confirm these results, further large-scale prospective studies are warranted.

Is indoor environment a risk factor of building-related symptoms?

The indoor environment, particularly indoor air quality (IAQ), is significantly associated with building-related symptoms (BRSs) in humans. In our previous studies, we demonstrated a significant relationship between BRSs and indoor chemical concentrations. In Japan, the Ministry of Health, Labor, and Welfare (MHLW) guideline recommends an air quality target of 13 volatile organic compounds (VOCs) and a provisional target of 400 µg/m3 for total VOCs (TVOC). The objective of this study was to determine the relationship between TVOC levels and the risk of BRSs using the Japanese provisional target TVOC level of 400 µg/m3. The relationship between odor intensity and BRSs while the TVOC levels were under 400 µg/m3 was also examined. The study was conducted in a laboratory house (LH) on the campus of Chiba University from 2017-2019. The study included 149 participants who spent 60 minutes in the LH. The participants were asked to evaluate the IAQ of the LH. A significant relationship between the risk of BRSs and the provisional target TVOC level was observed (odds ratio: 2.94, 95% confidence interval: 1.18-7.35). Furthermore, a significant relationship between odor intensity and risk of BRSs in spaces with TVOC levels less than 400 µg/m3 was detected (odds ratio: 6.06, 95% confidence interval: 1.21-30.44). In conclusion, the risk of BRSs is significantly lower in spaces with low TVOC levels and low odor intensity. Reducing the concentration of airborne chemicals and odor intensity may improve IAQ and prevent BRSs.

Effectiveness of a community-based integrated care ward (CICW) on 90-day readmission among the elderly people: a retrospective cohort study of a rural area in Japan.

Objective: Community-based integrated care wards (CICW) play a role in supporting the return of patients to their homes. However, studies investigating the readmission risk associated with CICW are lacking. To investigate the influence of CICW on readmission, we conducted a retrospective cohort study among Japanese elderly people. Materials and Methods: This study used data from the Diagnosis Procedure Combination (DPC) and medical records of the Hamada Medical Center, Shimane Prefecture in 2014-2019. The number of subjects and readmission in each hospitalization case (general ward only [GW] and CICW) were 1,521 and 416 subjects and 152 and 49 cases, respectively. We selected the hospitalization cases for heart failure (I30-I52), ischemic heart disease (I20-I25), pneumonia (J09-J18), chronic lower respiratory tract diseases (J40-J47), intestinal diseases (K55-K64), cerebrovascular disease (I60-I69), gallbladder, bile duct, and pancreatic diseases (K80-K87) from the International Statistical Classification of Diseases and Related Health Problems (ICD-10). The hazard ratios (HRs) and 95% confidence intervals (CIs) for readmission via a CICW were estimated using a multivariate Cox proportional hazards model. Results: The HRs for readmission associated with CICW were not different between the shorter and longer durations, considering the percentage of CICW stay. Compared with GW cases, the HR of CICW cases was 0.40 (95% CI, 0.17-0.92) in coordination with outside agencies of hospital discharge support. While the HR of GW cases was 2.35 (95% CI 1.01-5.47), a significantly increased risk was observed in people living alone. A similar risk was not observed in CICW cases with the HR of 0.56 (95% CI 0.15-2.07). Conclusion: The present study observed decreased risk of readmission among the patients discharged from CICW, compared to GW. Further research is required to clarify the causal factors for this decreased risk.

Impact of the Changes in the Frequency of Social Participation on All-Cause Mortality in Japanese Older Adults: A Nationwide Longitudinal Study.

Previous studies have shown that more frequent social participation was associated with a reduced risk of mortality. However, limited studies have explored the changes in the frequency of social participation in older adults. We investigated the impact of the changes in the frequency of social participation on all-cause mortality in Japanese older adults aged 60 years and older. The current study, conducted as a secondary analysis, was a retrospective cohort study using open available data. The participants were 2240 older adults (45.4% male and 54.6% female) sampled nationwide from Japan who responded to the interview survey. Changes in the frequency of social participation were categorized into four groups (none, initiated, decreased, and continued pattern) based on the responses in the baseline and last surveys. The Cox proportional-hazards model showed a decreased risk of all-cause mortality in decreased and continued patterns of social participation. Stratified analysis by sex showed a decreased risk of mortality in the continued pattern only among males. The results of the current study suggest that the initiation of social participation at an earlier phase of life transition, such as retirement, may be beneficial for individuals.

Association between alcohol intake pattern and metabolic syndrome components and simulated change by alcohol intake reduction: A cross-sectional study from the Japan Multi-Institutional Collaborative Cohort Study.

To investigate the association between alcohol intake pattern in amount and frequency and metabolic syndrome (Mets) components, we simulated the change in the prevalence of Mets components by intake reduction. In order to manage Mets, alcohol intake reduction with moderation of intake pattern is required. However, evidence investigating the comparative impact of alcohol intake reduction in amount and frequency for Mets components is limited. We conducted a large-scale cross-sectional study in the general Japanese population. The study subjects included 37,371 non-drinkers and current drinkers recruited in the Japan Multi-Institutional Collaborative Cohort Study. Odds ratios (ORs) for Mets components according to alcohol intake amount and frequency were estimated using a multiple logistic regression model. The prevalence of Mets components was estimated after assumed alcohol intake reduction of a) none, b) 10 g/day (men) or 5 g/day (women), c) 20 g/day (men) or 10 g/day (women), d) less than 20 g/day (men) or 10 g/day (women) for moderate-to-heavy drinkers, e) 1-2 times/week, and f) 3-4 times/week. The ORs with alcohol intake amount and frequency increased with high blood pressure while decreasing with dyslipidemia. A J-shaped association was observed between intake amount and Mets. The estimated prevalence (%) of high blood pressure and dyslipidemia in men were a) 45.2, b) 43.0, c) 41.4, d) 40.4, e) 42.9, and f) 42.0; and a) 50.3, b) 51.8, c) 52.9, d) 50.2, e) 52.7, and f) 53.4 in women. The estimated prevalence of high blood pressure in women did not evidently decrease. Simulated alcohol intake reduction showed decreased prevalence for high blood pressure and increased prevalence for dyslipidemia in men after reduced intake amount and frequency. The largest decreased prevalence for high blood pressure was observed in men when all moderate-to-heavy drinkers reduced their alcohol intake amount to less than 20 g/day.

Associations of Nutrient Patterns with the Prevalence of Metabolic Syndrome: Results from the Baseline Data of the Japan Multi-Institutional Collaborative Cohort Study.

: The association between nutrient patterns and metabolic syndrome (MetS) has not been examined in a Japanese population. A cross-sectional study was performed on 30,108 participants (aged 35-69 years) in the baseline survey of the Japan Multi-Institutional Collaborative Cohort Study. Dietary intake was assessed using a 46-item food frequency questionnaire. MetS was diagnosed according to the Joint Interim Statement Criteria of 2009, using body mass index instead of waist circumference. Factor analysis was applied to energy-adjusted intake of 21 nutrients, and three nutrient patterns were extracted: Factor 1 (fiber, potassium and vitamins pattern); Factor 2 (fats and fat-soluble vitamins pattern); and Factor 3 (saturated fatty acids, calcium and vitamin B2 pattern). In multiple logistic regression analysis adjusted for sex, age, and other potential confounders, Factor 1 scores were associated with a significantly reduced odds ratio (OR) of MetS and all five components. Factor 2 scores were associated with significantly increased prevalence of MetS, obesity, and high blood pressure. Factor 3 scores were significantly associated with lower OR of MetS, high blood pressure, high serum triglycerides and low HDL cholesterol levels. Analysis of nutrient patterns may be useful to assess the overall quality of diet and its association with MetS.

Positive Association of Plasma Homocysteine Levels with Cardio-Ankle Vascular Index in a Prospective Study of Japanese Men from the General Population.

AIM: Observational studies have reported that elevated homocysteine (Hcy) levels are associated with the risk of cardiovascular disease (CVD). However, interventions that lower Hcy do not provide a corresponding risk reduction. Therefore, the causal role of Hcy in CVD remains unclear. This 5-year prospective study investigated the associations of Hcy levels, folate intake, and host factors with arterial stiffness among the general Japanese population. METHODS: We prospectively recruited 658 participants (40-69 years old) from the general population during regular health checkup examinations. Arterial stiffness was evaluated using the cardio-ankle vascular index (CAVI) at baseline and the 5-year follow-up. Folate intake was estimated using a structured questionnaire. Genotyping was used to evaluate the MTHFR C677T and MS A2756G gene polymorphisms. Ultrafast liquid chromatography was used to measure total plasma Hcy levels. Association between these variables and CAVI values was evaluated using general linear regression and logistic regression models that were adjusted for atherosclerosis-related factors. RESULTS: Men had higher Hcy levels and CAVI values and lower folate intake than women (all, p＜0.001). At baseline, Hcy, folate intake, and the two genotypes were not associated with CAVI values for both sexes. Among men, Hcy levels were positively associated with CAVI values at the 5-year follow-up (p=0.033). Folate intake and the two genotypes were not associated with the 5-year CAVI values. CONCLUSION: Plasma Hcy may be involved in arterial stiffness progression, as monitored using CAVI, among men.

Genetic variants of SLC17A1 are associated with cholesterol homeostasis and hyperhomocysteinaemia in Japanese men.

Hyperuricaemia is an undisputed and highly predictive biomarker for cardiovascular risk. SLC17A1, expressed in the liver and kidneys, harbours potent candidate single nucleotide polymorphisms that decrease uric acid levels. Therefore, we examined SLC17A1 polymorphisms (rs1165196, rs1179086, and rs3757131), which might suppress cardiovascular risk factors and that are involved in liver functioning, via a large-scale pooled analysis of the Japanese general population in a cross-sectional study. Using data from the Japan Multi-Institutional Collaborative Cohort Study, we identified 1842 participants of both sexes, 35-69-years-old, having the requisite data, and analysed their SLC17A1 genotypes. In men, logistic regression analyses revealed that minor alleles in SLC17A1 polymorphisms (rs1165196 and rs3757131) were associated with a low-/high-density lipoprotein cholesterol ratio >2.0 (rs1165196: odds ratio [OR], 0.703; 95% confidence interval [CI], 0.536-0.922; rs3757131: OR, 0.658; 95% CI, 0.500-0.866), and with homocysteine levels of >10.0 nmol/mL (rs1165196: OR, 0.544; 95% CI, 0.374-0.792; rs3757131: OR, 0.509; 95% CI, 0.347-0.746). Therefore, these polymorphisms had dominant negative effects on cholesterol homeostasis and hyperhomocysteinaemia, in men, independent of alcohol consumption, physical activity, or daily energy and nutrition intake. Thus, genetic variants of SLC17A1 are potential biomarkers for altered cholesterol homeostasis and hyperhomocysteinaemia in Japanese men.

Polymorphisms in CYP19A1, HSD17B1 and HSD17B2 genes and serum sex hormone level among postmenopausal Japanese women.

OBJECTIVE: Extraovarian sex hormone production plays an important role in estrogen biosynthesis in postmenopausal women. We examined possible associations between serum sex hormone level and polymorphisms in CYP19A1, HSD17B1, and HSD17B2. We also assessed possible interaction between these polymorphisms and current overweight. METHODS: We conducted a cross-sectional study. 785 Japanese natural postmenopausal women were randomly selected from the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study database. Information on lifestyle factors was obtained from a self-administered questionnaire. Serum estrogens and androgens levels were measured by liquid chromatography-tandem mass spectrometry. Four tag SNPs (single nucleotide polymorphisms) of CYP19A1, one missense SNP of HSD17B1 and three tag SNPs of HSD17B2 were examined by Invader assay. A trend test was conducted using linear regression. RESULTS: After adjustment for multiple comparisons, we found that rs4441215 and rs936306 in CYP19A1 and rs4888202 and rs2955160 in HSD17B2 were associated with differences in serum estrone level. Further, rs4441215 and rs936306 were associated with differences in serum estradiol level. None of these polymorphisms showed a significant interaction with current body mass index (BMI). CONCLUSIONS: Our findings suggested that CYP19A1 and HSD17B2 polymorphisms might be associated with circulating sex hormone levels in Japanese postmenopausal women, independent of current BMI.