Objective: γ-glutamyl transpeptidase (γ-GTP) is generally used as a marker for alcohol abuse and liver damage, but some people have a high serum γ-GTP for no obvious reason. This study examined an association between GGT1 gene polymorphism (rs4820599) and serum γ-GTP levels, taking into account age and alcohol drinking status.

Methods: The subjects for analysis were 4,559 males and 5,212 females, aged 35–69 years and apparently healthy, who participated in the Japan Multi-Institutional Collaborative Cohort Study (J-MICC Study).

Results: Mean serum γ-GTP concentrations were 42.1 U/L in males and 21.7 U/L in females, the difference being statistically significant (p<0.0001, adjusted for 5-year age groups and drinking status). The highest mean serumγ-GTP (49.3 U/L) was observed among current male drinkers with the G/G genotype in GGT1 polymorphism, whereas non-current female drinkers with the A/A genotype had the lowest mean concentration (19.9 U/L). Among non-current drinkers, odds ratios (ORs) for high serum γ-GTP (≥50 U/L) adjusted for sex, 5-year age groups and high BMI (≥25 kg/m²) were 1.54 (95% CI, 1.14–2.07) for A/G and 2.36 (95% CI, 1.40–3.96) for G/G, compared to the A/A genotype (p for trend <0.001).

Conclusion: The present study confirmed that the intronic A>G polymorphism (rs4820599) in GGT1 affects serum γ-GTP levels in a large population. The G allele seems to increase serum γ-GTP concentrations particularly in non-current drinkers. The normal range of serum γ-GTP might differ according to the genotype in GGT1 polymorphism.

Objective: We previously reported the usefulness of brachial-ankle pulse wave velocity (baPWV) based on a cross-sectional analysis of data from Ningen Dock and general health screening. In our previous studies, we observed a strong relationship between the clustering of atherosclerosis risk factors and baPWV. In the present study, to evaluate this relationship further, we performed a longitudinal analysis over a 10-year period.

Methods: Of the 22,377 individuals in whom baPWV was measured using form ABI/PWV at our facility, 626 males with measurements in both the first year and the 10th year were selected as subjects.

Results: A significant positive correlation was observed between baPWV and the number of atherosclerosis risk factors in the first year of measurement, similar to our previous study. Over 10 years, the amount of change in all 626 males was about 100 cm/sec and the number of atherosclerosis risk factors increased from 1.3 to 1.6. The change in baPWV over 10 years tended to be smaller the greater the number of atherosclerosis risk factors. However, the values of baPWV in the 10th year were still higher when there were a greater number of risk factors.

Conclusion: It is significant to measure baPWV continuously and pay attention to changes in it since it may be possible to suppress increases in baPWV by reducing the number of atherosclerosis risk factors. Furthermore, our findings suggest that early interventions in atherogenic risk control are required to reduce increases in the stiffness of large arteries.

Objective: Hyperuricemia is a lifestyle-related disease. Simple, good healthy habits for everyone have been reported, among them Belloc and Breslow’s seven items, Morimoto’s eight items, and Ikeda’s six items. A better lifestyle may prevent hyperuricemia. However, no study has been done on an association between the incidence of hyperuricemia and combined impact of practicing such simple healthy habits. The objective of this study was to determine which of above three sets of healthy habits had the greatest impact in preventing hyperuricemia.

Methods: The effect of the healthy habits score for each of the three sets of habits on the development of hyperuricemia was evaluated using Cox-hazard regression analysis. The cumulative 6-year incidence of hyperuricemia was calculated and compared among groups using the log-rank test adjusted for age in the present open retrospective cohort study.

Setting and Subjects: 5,049 subjects who underwent a health check-up and provided responses to a self-administered questionnaire on the above healthy lifestyle habits were divided into a poor, moderate, and favorable lifestyle group. Hyperuricemia was defined as serum uric acid of 7.0 mg/dL and over in men, and 5.5 mg/dL and over in women, or treatment with anti-hyperuricemia agents during follow-up.

Results: For the Breslow and Morimoto’s habits, a reduction in hyperuricemia was not observed in the favorable group in women. Regarding Ikeda’s healthy habits, the development of hyperuricemia was significantly lower in the moderate risk group and the favorable risk group, with a 22% and a 40% reduction in men, respectively. In women, a reduction was observed in the favorable risk group, of 47%.

Conclusion: For Ikeda’s six habits only, the incidence of hyperuricemia in the favorable group was lower than that in the poor group for both men and women. To our knowledge, our study was the first to observe an impact of Ikeda’s six healthy habits in decreasing the risk of hyperuricemia among three sets of simple good healthy habits.

Background: Independent associations between albuminuria and metabolic risk factors, including liver and kidney function tests, have not been well studied.

Methods: This was a cross-sectional study on a health screening population including 359 men and 200 women who were apparently healthy. Albuminuria was defined as urinary albumin of 17 mg/g creatinine or higher in men and 25 mg/g creatinine or higher in women using spot morning urine specimens. Using multivariable linear regression and multivariable logistic regression models, independent associations between albuminuria and metabolic risk factors, including liver and kidney function tests, were investigated.

Results: Albuminuria was found in 48 subjects (8.6%). Metabolic risk factors except for HDL cholesterol were significantly positively correlated with log urinary albumin. In multivariable linear regression models, SBP , fasting glucose, log high-sensitivity C-reactive protein (hs-CRP), AST, serum albumin and estimated glomerular filtration rate, but not ALT, were independently positively associated with log urinary albumin. In multivariable logistic regression models, BMI or SBP, fasting glucose, log hs-CRP and AST, but not ALT, were independently positively associated with albuminuria.

Conclusions: AST was associated with albuminuria independently of metabolic risk factors in apparently healthy subjects.

The FIB4 index (based on age, AST and ALT levels, and platelet counts) is expected to be useful for evaluating hepatic fibrosis in patients with not only viral hepatitis but also nonalcoholic fatty liver disease (NAFLD). We investigated the FIB4 index in a large Japanese population with NAFLD undergoing health check-ups to evaluate the prevalence of severe fibrosis in NAFLD. We recruited a total of 5,410 people with NAFLD receiving health check-ups from five centers in Japan. The FIB4 index was assessed as: age (years)×AST (IU/L)/(platelet count (10⁹/L)×√ALT (IU/L)). Participants were divided into 3 groups according to the proposed cut-off points (<1.45, 1.45–3.25, >3.25). The FIB4 index in the overall study population was 1.027±0.549. Of the 5,410 people with NAFLD, 4,729 (87.4%) had an FIB4 index below the low cut-off point (<1.45), 654 (12.1%) had an FIB4 index in the indeterminate range (1.45–3.25) and 27 (0.5%) had an FIB4 index above the high cut-off point (>3.25). In conclusion, most (87%) Japanese people with NAFLD are unlikely to have severe fibrosis, while in the remaining 13% severe fibrosis cannot be ruled out so such people should be considered for referral to hepatologists or liver biopsies should be conducted on them.