Casual serum triglyceride as a predictor of premature type 2 diabetes mellitus: an 8-year cohort study of middle-aged Japanese workers.

BACKGROUND: The utility of casual serum triglyceride (TG) as a predictor of type 2 diabetes mellitus (DM) is unclear, especially during the most productive years. METHODS: Participants were 3271 workers (913 men and 2358 women, age 20-57) without DM at baseline. They underwent consecutive annual medical check-ups for 8 years. The association between newly diagnosed DM and casual serum TG level was determined by classifying the participants into 4 groups according to casual serum TG level at baseline: below 50 mg/dL (group A), 50-100 mg/dL (group B), 100-150 mg/dL (group C), and ≥150 mg/dL (group D). The effects of casual serum TG level in combination with sex, obesity, or serum glucose level on newly diagnosed DM were also evaluated. RESULTS: A total of 222 newly diagnosed type 2 DM cases with a mean age of 50 years old were observed during the follow-up period, i.e., 10/406 in group A, 66/1534 in group B, 58/712 in group C, and 88/619 in group D. Compared with group A, the odds ratio (ORs) for newly diagnosed DM (after adjusting for DM-associated factors) was found to increase with casual serum TG level: 1.38 (group B), 1.79 (group C), and 2.36 (group D). Moreover, the OR for newly diagnosed DM was higher in participants with high casual serum TG levels who were also male (OR 2.46), obese (OR 4.18), or had a high serum glucose level (OR 6.96) than in the reference group. CONCLUSIONS: Serum TG level ≥150 mg/dL when fasting or nonfasting is a significant predictor of type 2 diabetes in middle-aged Japanese workers.

Serum Polyunsaturated Fatty Acid Composition and Serum High-Sensitivity C-Reactive Protein Levels in Healthy Japanese Residents: The KOBE Study.

BACKGROUND/OBJECTIVES: Serum polyunsaturated fatty acid (PUFA) composition reflects dietary intake and is related to risks for cardiovascular diseases. We hypothesized that serum n-3 PUFA composition, especially including long-chain n-3 PUFA such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), is associated with inflammatory status, which is related to increased risk for cardiovascular diseases. SUBJECTS/METHODS: We investigated the relationship between serum PUFA composition and high-sensitivity C-reactive protein (hs-CRP) levels in a cross-sectional study among 1,102 healthy men and women aged 40-74 years who reside in Kobe City. Multiple linear regression models that predict hs-CRP level were prepared to confirm the contribution of serum total n-3 PUFA, long-chain n-3 PUFA, EPA and DHA compositions after adjusting for other PUFAs and atherosclerotic risk factors. RESULTS: The serum n-3 PUFA, particularly long-chain n-3 PUFA, compositions were inversely associated with the hs-CRP levels. The standardized regression coefficient was -0.089 (p < 0.01) for total n-3 PUFA, -0.091 (p < 0.01) for long-chain n-3 PUFA, -0.071 (p = 0.03) for EPA, and -0.068 (p = 0.04) for DHA. The n-6 PUFA compositions were also inversely associated with the hs-CRP levels (-0.169 [p < 0.01] for total n-6 PUFA and -0.159 [p < 0.01] for linoleic acid). CONCLUSIONS: The serum n-3 PUFA compositions were inversely related with the hs-CRP levels, similar associations were also observed in n-6 PUFA compositions. Our results suggest that dietary PUFA intake was inversely associated with attenuated inflammation in healthy Japanese population.

Japanese men have larger areas of visceral adipose tissue than Caucasian men in the same levels of waist circumference in a population-based study.

Visceral adipose tissue (VAT) is an independent risk factor for metabolic and cardiovascular disorders. There has been no study that demonstrated different abdominal fat distribution between Asian and Caucasian men. As the Japanese are less obese but more susceptible to metabolic disorders than Caucasians, they may have larger VAT than Caucasians at similar levels of obesity. We compared the abdominal fat distribution of the Japanese (n=239) and Caucasian-American (n=177) men aged 40-49 years in groups stratified by waist circumference in a population-based sample. We obtained computed tomography images and determined areas of VAT and subcutaneous adipose tissue (SAT). We calculated VAT to SAT ratio (VSR). The Japanese men had a larger VAT and VSR in each stratum, despite substantially less obesity overall. In multiethnic studies, difference in abdominal fat distribution should be considered in exploring factors related to obesity.

Are comprehensive environmental changes as effective as health education for smoking cessation?

OBJECTIVES: To compare the effectiveness of health education on smoking cessation for all smokers regardless of their willingness to quit smoking and cumulative environmental changes including designation of smoking places, legislation, and price rise. DESIGN: Comparison of smoking cessation rates over two time periods: the period of health education on smoking cessation (1997-1999), and the period of cumulative environmental changes (2002-2004). SETTING: An occupational setting in a radiator manufacturing factory in Japan. SUBJECTS: All habitual male smokers who remained in the worksite through the pertinent time period (n = 202 in the period of health education and n = 170 in the period of environmental changes). MAIN OUTCOME MEASUREMENTS: Smoking cessation rates at the end of each time period. RESULTS: The smoking cessation rates over the periods of health education and environmental changes were 8.9% and 7.1%, respectively. There was no difference between these two proportions in a chi2 test (p = 0.513). The age adjustment did not significantly alter the cessation rate. CONCLUSIONS: Cumulative environmental changes are fairly effective in promoting smoking cessation, and may yield similar smoking cessation rates as a health education intervention reaching all smokers regardless of their willingness to quit smoking.

Different effects of blood pressure on mortality from stroke subtypes depending on BMI levels: a 19-year cohort study in the Japanese general population--NIPPON DATA80.

To evaluate the relationship between blood pressure and cerebrovascular death depending on body mass index (BMI) levels, we analysed a database of 9338 subjects from the National Integrated Project for Prospective Observation of Non-communicable Disease and its Trends in the Aged, which was originally conducted a baseline survey in 1980 and followed up in 1999. Relative risk (RR) and a 95% confidence interval (CI) of death from total stroke, cerebral infarction, and intracerebral haemorrhage after adjusting for age, sex, serum cholesterol, albumin, glucose, the use of antihypertensive agents, a past history of diabetes, BMI, smoking, and drinking were estimated with the Cox-proportional hazard model in the BMI tertile groups of a representative Japanese population. Cutoff points of BMI tertiles are 21.2 and 23.8 kg/m2. The results indicated that a 10 mmHg systolic blood pressure (SBP) increase was associated with mortality from intracerebral haemorrhage at low and middle BMI groups (RR= 1.38 and 1.23; 95% CI=1.17-1.62 and 1.03-1.47, respectively). SBP was positively associated with mortality from cerebral infarction in middle and high BMI groups (RR=1.19 and 1.21; 95% CI=1.06-1.33 and 1.06-1.38, respectively). The effects of diastolic blood pressure on intracerebral haemorrhage and infarction had the same tendency as those of SBP. These results suggested that the causal effect of blood pressure on stroke subtypes might be modified by BMI.