Lower physical activity is a risk factor for a clustering of metabolic risk factors in non-obese and obese Japanese subjects: the Takahata study.

In several countries including Japan, people without obesity but with a clustering of metabolic risk factors (MetRFs) were not considered to have the metabolic syndrome (MetS). Here, we examined whether lifestyle characteristics differed between non-obese and obese subjects with or without a clustering of MetRFs. From a population-based cross-sectional study of Japanese subjects aged ≥ 40 years, 1,601 subjects (age: 61.9 ± 10.3 years; 710/891 men/women) were recruited. Physical activity status and daily nutritional intake were estimated using questionnaires. A clustering of MetRFs was defined based on the presence of at least two non-essential risk factors for the diagnosis of the MetS in Japan. Energy intake was not higher in subjects with a clustering of MetRFs compared with those without. Among men, energy expenditure at work was significantly lower in non-obese (9.0 ± 8.2 vs. 11.3 ± 9.3 metabolic equivalents (METs), P = 0.025) and obese (9.0 ± 7.9 vs. 11.6 ± 9.4 METs, P = 0.017) subjects with a clustering of MetRFs than in those without. Multiple logistic regression analysis showed that energy expenditure at work was significantly associated with a clustering of MetRFs after adjusting for possible confounding factors including total energy intake. The ORs (per 1 METs) were 0.970 (95% CI, 0.944-0.997; P = 0.032) in non-obese men and 0.962 (0.926- 0.999; P = 0.043) in obese men. Similar associations were not observed in women. In Japanese males, lower physical activity, but not excessive energy intake, is a risk factor for a clustering of MetRFs independent of their obesity status.