Mild metabolic abnormalities, abdominal obesity and the risk of cardiovascular diseases in middle-aged Japanese men

Aim: We investigated the individual and population impacts of mild abnormalities associated with metabolic syndrome (blood pressure, lipids and glucose) and abdominal obesity, for which lifestyle modification is initially applicable, on cardiovascular disease risk.Methods: Using a cohort study of 2,685 Japanese men aged 35 to 59 years with an 11-year follow-up period, we calculated the relative risks for cardiovascular diseases due to mild metabolic abnormalities that included at least one of the following three conditions: 1) systolic blood pressure 130-139 mmHg and/or diastolic blood pressure 85-89 mmHg; 2) triglycerides 150-299 mg/dL and/or high-density lipoprotein cholesterol 35-39 mg/dL; and 3) fasting plasma glucose 110-125 mg/dL and/or abdominal obesity. Participants with a mild metabolic abnormality were compared to participants with no metabolic abnormality or abdominal obesity. The population attributable fraction of these abnormalities for cardiovascular diseases was also estimated.Results: At baseline, 9.8% and 21.8% of the total population had a mild metabolic abnormality with or without abdominal obesity, respectively, while 7.5% had isolated abdominal obesity without any metabolic abnormality. A mild metabolic abnormality with or without abdominal obesity and isolated abdominal obesity increased the risk of cardiovascular disease by 2.68-fold, 1.49-fold, and 2.36-fold, respectively. Approximately 20% of cardiovascular diseases in the total population were attributable to either mild metabolic abnormalities or isolated abdominal obesity.Conclusion: The importance of lifestyle modification should be acknowledged, especially in cases of mild metabolic abnormality and/or abdominal obesity, which may contribute to approximately 20% of the population burden for cardiovascular diseases.