Abstract
Objective: To elucidate the relationships between metabolic syndrome (MetS)-related factors and all-cause mortality over a 28-year follow-up in O City, Ehime Prefecture, Japan. Materials and Methods: Using the Basic Resident Registration System, we analyzed data from 3,931 participants aged 40-74 years (1,360 men and 2,571 women) who underwent annual medical examinations based on the Geriatric Health Care Law between 1996 and 1998. Cox proportional hazards regression was used to assess associations between all-cause mortality and nine variables, adjusted for sex and age: MetS; body mass index (BMI: underweight, <18.5 kg/m(2); normal weight, 18.5 to <25.0 kg/m(2); overweight, ≥25.0 kg/m(2)); height; waist circumference abnormality; elevated blood pressure/hypertension; dyslipidemia; prediabetes/diabetes; alcohol consumption; and smoking. Results: Of the participants, 1,938 died. In both men and women, MetS was not associated with all-cause mortality. Underweight status (hazard ratio [HR]=1.93, 95% confidence interval [CI]: 1.43-2.60 for men; HR=1.51, 95% CI: 1.16-1.97 for women), prediabetes/diabetes (HR=1.35, 95% CI: 1.13-1.62 for men; HR=1.36, 95% CI: 1.12-1.66 for women), and smoking (HR=1.45, 95% CI: 1.25-1.67 for men; HR=1.95, 95% CI: 1.48-2.58 for women) were significantly associated with all-cause mortality. Conclusion: Avoiding smoking, underweight status, and prediabetes/diabetes may help extend life expectancy.