Objective-To investigate the association between duration of overtime and the development of impaired fasting glucose (IFG) or type 2 diabetes mellitus (DM). Methods-A cohort of 1266 Japanese male oYce workers aged 35-59 years and free of IFG (fasting plasma glucose concentration 6.1-6.9 mmol/l), type 2 DM (fasting plasma glucose concentration of 7.0 mmol/l or more or taking hypoglycaemic medication), history of diabetes, or medication for hypertension were re-examined over 5 successive years after their initial examinations in 1994. Results-138 men developed IFG or type 2 DM during the 5736 person-years of follow up. After controlling for potential predictors of diabetes, the relative risks of IFG or type 2 DM, compared with those who worked <8.0 hours a day, were 0.82 (95% confidence interval (95% CI) 0.54 to 1.26), 0.69 (95% CI 0.38 to 1.26), 0.63 (95% CI: 0.37 to 1.09), and 0.50 (95% CI: 0.25 to 0.98) for those who worked 8.0-8.9, 9.0-9.9, 10.0-10.9, and of 11.0 hours or more a day, respectively (p for trend=0.020). 87 and 54 men developed IFG and type 2 DM during the 5817 and 5937 person-years of follow up, respectively. The multivariate adjusted relative risks of IFG tended to decrease with an increase in hours of overtime work a day, but did not reach significance (p for trend=0.202). On the other hand, the multivariate adjusted relative risks of type 2 DM significantly decreased with an increase in hours of overtime work a day (p for trend=0.014). Conclusion-Longer overtime is a negative risk factor for the development of IFG or type 2 DM in Japanese male oYce workers. (Occup Environ Med 2001;58:569-574)

Abstract. Nakanishi N, Nishina K, Li W, Sato M, Suzuki K, Tatara K (Osaka University Graduate School of Medicine, Osaka; and Japan Labor and Welfare Association, Tokyo; Japan). Serum c-glutamyltransferase and development of impaired fasting glucose or type 2 diabetes in middle-aged Japanese men. J Intern Med 2003; 254: 287-295.Objective. To investigate the association between serum c-glutamyltransferase (GGT) and risk for development of diabetes. Design. Longitudinal study (followed from 1994 to 2001). Setting. A work site in Japan. Subjects. A total of 2918 Japanese male office workers aged 35-59 years who did not have impaired fasting glucose (IFG) (a fasting plasma glucose concentration of 6.1-6.9 mmol L )1 ), type 2 diabetes (a fasting plasma glucose concentration of P7.0 mmol L )1 or receipt of hypoglycaemic medication), medication for hypertension or hepatitis, alanine aminotransferase concentrations higher than three times the upper limit of the reference range or a history of cardiovascular disease at study entry. Main outcome measure. Incidence of IFG or type 2 diabetes over a 7-year period.Results. With adjustment for potential risk factors for diabetes, the relative risk for IFG compared with serum GGT <16 U L )1 was 1.23 (95% CI, 0.79-1.90), 1.50 (CI, 0.97-2.32) and 1.70 (CI, 1.07-2.71) with serum GGT of 16-24, 25-43 and P44 U L )1 , respectively (P for trend ¼ 0.014). The respective relative risks for type 2 diabetes compared with serum GGT <16 U L )1 were 2.54 (CI, 1.29-5.01), 2.64 (CI, 1.33-5.23) and 3.44 (CI, 1.69-6.70) (P for trend ¼ 0.002). From stratified analyses by body mass index (BMI) and alcohol intake, a stronger linear association between serum GGT and development of IFG or type 2 diabetes was found in men with a BMI P23.2 kg m )2 in both those who drank <46 and P46 g day )1 of ethanol. Conclusions. The risk for development of IFG or type 2 diabetes increased in a dose-dependent manner as serum GGT increased in middle-aged Japanese men. The increased relative risk for IFG or type 2 diabetes associated with serum GGT was more pronounced in obese men.

Light to moderate alcohol consumption seems to have an important influence on BP in both young and middle-aged Japanese men.

, but also in their Japanese counterparts [4][5][6][7] . Psychological distress is considered to be a risk factor for MetS. A cross-sectional study of 87 monozygotic and 86 dizygotic male twin pairs in the US showed that depressive symptoms were associated with metabolic risk factors such as body mass index, waistto-hip ratio, mean arterial pressure, triglycerides and glucose 8) . A 7-year prospective study of 425 middleaged women in the US showed that depressive symptoms were predictive of a risk of MetS 9). A 14-year large-scale prospective study of 10,308 middle-aged men and women in England showed that chronic work stress was associated with a risk of MetS 10) . Finally, a recent 15-year prospective study of 523 middle-aged pre-menopausal women in the US also indi-

Light to moderate alcohol consumption seems to have an important influence on BP in both young and middle-aged Japanese men.