Risk assessment chart for predicting fatty liver in Japanese subjects.

OBJECTIVE: The diagnosis of fatty liver is done mainly by ultrasonography, which it is not included in the usual health checkup examinations. The aim of this study was to develop an index to predict the existence of fatty liver using tests that are part of specific health examinations. METHODS: A total of 7,305 Japanese (4,042 men; 3,263 women) who underwent annual health checks were enrolled. Body mass index (BMI), Waist circumference (WC), blood pressure, and levels of triglyceride (TG), high-density lipoprotein cholesterol, fasting plasma glucose (FPG), alanine aminotransferase (ALT), and gamma-glutamyl transpeptidase were used to predict fatty liver, and a stepwise procedure was used to select an optimal subset of dummy regressors. The probabilities for predicting fatty liver were calculated from the logistic regression equation using the constant and coefficients for each variable. RESULTS: Risk assessment charts for predicting the probability of fatty liver were developed. These probabilities were displayed in a color-coded manner by combining BMI, TG, FPG, ALT, and WC. CONCLUSION: Our fatty liver-predicting index consisted of the components of metabolic syndrome (MetS) and ALT, thus indicating a close relationship of fatty liver and MetS. The use of this index enables quantitative assessments of the severity of MetS.

Evaluation of high-density lipoprotein cholesterol levels in Japanese women.

OBJECTIVE: The aim of the present study was to clarify the significance of high levels of high-density lipoprotein cholesterol (HDL-C) in Japanese women receiving an annual health check-up. METHODS: A total of 1879 women who were not taking medication for hypertension, diabetes or dyslipidemia, with no prior history of ischemic heart disease, cerebrovascular disease or chronic renal failure were analyzed. First, the association between HDL-C and homeostasis model assessment of insulin resistance (HOMA-IR) was studied. Next, the association between HDL-C and the number of metabolic syndrome (MetS) risk factors, including HOMA-IR, was determined. In addition, clinical parameters including HOMA-IR, number of MetS risk factors, smoking, exercise, and alcohol consumption habits were compared according to HDL-C level. RESULTS: HOMA-IR was lower in subjects with elevated HDL-C. Additionally, a lower body mass index (BMI), waist circumference (WC), fasting plasma glucose (FPG), and triglycerides (TG) were observed in subjects with higher HDL-C. Moreover, the proportion of subjects who were obese, or those who had high FPG, high TG, and a high number of MetS risk factors was lower in subjects with higher HDL-C. Both obesity and smoking were associated with reduced HDL-C levels. Increasing levels of alcohol consumption, from < 25 g/day, to 25 -< 50 g/day, to 50 -< 75 g/day, were associated with a progressive increase in HDL-C level, but a progressive reduction in HOMA-IR. However, this apparent benefit of alcohol intake on HDL-C and HOMA-IR disappeared in subjects who drank ≥ 75 g/day. CONCLUSIONS: Female subjects who were not obese, did not smoke, and drank < 75 g alcohol/day had elevated HDL-C levels, which were associated with improved insulin sensitivity. Drinking alcohol in excess of 75 g/day appeared to provide no advantages in terms of HDL-C or HOMA-IR levels. Thus, it might be important for females to keep their alcohol intake below 75 g/day.

Long-term detraining increases the risk of metabolic syndrome in Japanese men.

OBJECTIVE: The aim of the present study was to examine the effect of long-term detraining on metabolic syndrome (MetS). METHODS: 1109 Japanese men were categorized by their exercise habits. Clinical data, number of MetS risk factors, and differences in lifestyle-related behaviors of the non-training group (n = 233) and the detraining group (n = 483) were compared with those of the training group (n = 87). RESULTS: Waist circumference and body mass index were significantly higher in the non-training group and the detraining group than in the training group, and also higher in the detraining group than in the non-training group. High-density lipoprotein cholesterol (HDL-C) was lower and low-density lipoprotein cholesterol (LDL-C) was higher in the non-training group and the detraining group than in the training group. Both the non-training group and the detraining group had more MetS risk factors than the training group. The odds ratio for smoking was higher in the detraining group than in the training group. CONCLUSIONS: Detraining results in similar degrees of obesity, low HDL-C, high LDL-C, and high MetS risk as non-training. To prevent lifestyle-related diseases, it is particularly important not only to encourage adults to become physically active, but also discourage active young people from discontinuing physical exercise.

Significance of high HDL cholesterol levels in Japanese men with metabolic syndrome.

OBJECTIVE: The objective was to clarify the significance of high high-density lipoprotein cholesterol (HDL-C) levels in the metabolic syndrome (MetS). The evaluation focused on insulin resistance as an indicator of early-stage MetS. METHODS AND SUBJECTS: Of 2705 men who first underwent an annual health check-up at Tokai University Hachioji Hospital, 2129 men were included in this study, after exclusion of those on medication for hypertension, diabetes or dyslipidemia, and those with a prior history of ischemic heart disease, cerebrovascular disease or chronic renal failure. MetS risk factors include the following five parameters: waist circumference, blood pressure, plasma glucose, triglycerides and HDL-C. The correlations between HDL-C and number of MetS risks with homeostasis model assessment of insulin resistance (HOMA-IR) were analyzed. HOMA-IR, number of risks, habits of smoking, exercise and drinking alcohol, stratified by HDL-C levels, were compared in MetS subjects. RESULTS: In cases with ≤2 risk factors, the higher the HDL-C, the lower the HOMA-IR. However, with ≥3 risk factors for MetS, the HOMA-IR increased when HDL-C was ≥90 mg/dL. In MetS subjects, the rate of alcohol intake ≥75 g/day was high when HDL-C was ≥90 mg/dL. CONCLUSION: In MetS subjects with high HDL-C levels, insulin resistance was increased. Therefore, in persons with high HDL-C levels, it is important to monitor the amount of alcohol consumption and reduce alcohol consumption to <75 g/day.

Optimal reference interval for homeostasis model assessment of insulin resistance in a Japanese population.

The aim of the present study was to establish a reference interval for homeostasis model assessment of insulin resistance (HOMA-IR) in a Japanese population based on the C28-A3 document from the Clinical and Laboratory Standards Institute (CLSI). We selected healthy subjects aged 20-79 years, with fasting plasma glucose < 100 mg/dL, body mass index < 25 kg/m(2) and alanine aminotransferase < 31 U/L. HOMA-IR values were log transformed, values beyond mean ± 3 standard deviations (SD) were truncated, and the mean ± 2 SD of log HOMA-IR values were taken as the upper and lower reference limits of HOMA-IR. We selected 2173 subjects as reference individuals, and 2153 subjects were used for analysis. The reference interval for HOMA-IR was established as between 0.4 and 2.4. This represents the first reference interval study for HOMA-IR that applies the stringent CLSI C28-A3 document. HOMA-IR ≥ 2.5 should be considered a reasonable indicator of insulin resistance in Japanese. (J Diabetes Invest, doi: 10.1111/j.2040-1124.2011.00113.x, 2011).