Motorized Transportation, Social Status, and Adiposity

Background: Increased dependence on motorized transportation may contribute to obesity. Countries in rapid socioeconomic transitions, like China, provide an opportunity to investigate such association. Purpose: The hypotheses were examined: that the increased dependence on motorized transportation is related to adiposity; and that this effect will be more pronounced in those adults with high socioeconomic status (SES) or living in urban regions. Methods: Data from the longitudinal China Health and Nutrition Survey conducted from 1997 till 2006 (n=3,853, aged 18~55yrs at baseline, 52%women, ~7.8years follow-up) were used to examine the association between motorization (none, 1-5years, >5years) and the changes in body weight and waist circumference (WC) by using multivariate regression. SES factors were obtained from questionnaires. Data were analyzed in 2010. Results: Use of motorized transportation >5years was related with ~1.2 kg larger weight gain(P=0.006) and ~1.0 cm larger WC gain(P=0.017) in men, when compared with the non-motorized group and adjusted for baseline age, anthropometry, dietary intake and follow-up time. These changes were slightly more pronounced in men with higher income or from rural areas, but the difference was not significant. In women, the tendency for motorization with weight gain was less pronounced(+1.1kg, P=0.008). Low education and high income were the most predominant factors. In 2006, motorization was associated with a 1.3-fold higher odds ratio for obesity (Ptrend=0.054) and abdominal obesity (Ptrend=0.047) in men, and a two-fold higer OR of obesity in women (Ptrend