The prevalence and associated factors of metabolic syndrome among Tibetan pastoralists in transition from nomadic to settled urban environment

Abstract

Objective: To study the prevalence and associated factors of metabolic syndrome (MS) among Tibetan pastoralists in transition from high altitude nomadic to settled urbanized environment, especially dietary factors. Methods: The community-based cross-sectional study included 920 Tibetan adults (men 419, women 501). Data were collected using questionnaires, anthropometric measurements, and biomarker tests. Questionnaires included socio-economic, lifestyle characteristics and food consumption. Principal component analysis was used to identify dietary patterns. The risk factors of MS and its components were analyzed by logistic regression model. Results: The prevalence rates of MS and its components were 32.8% (MS), 83.7% (decreased HDL-C), 62.1% (central obesity), 36.7% (elevated blood pressure), 11.8% (elevated TG), and 7.9% (elevated blood glucose), respectively. The prevalence of overweight was 31.2%, obesity 30.3%. Multivariate analysis showed smoking was associated factor for both of decreased HDL-C (OR=1.239, 95%CI: 1.025-1.496) and elevated TG (OR=1.277, 95%CI: 1.038-1.571). Alcohol drinking appeared as associated factor of elevated TG (OR=1.426, 95%CI: 1.055-1.927). However, physical activity showed as a protective factor for central obesity, decreased HDL-C, and elevated TG. With the increase of age, the adherence to the urban and western dietary patterns decreased, and that to the pastoral dietary pattern increased. By quintiles of dietary pattern scores, the urban dietary pattern was significantly associated with MS (trend test P=0.016). Conclusions: Tibetan pastoralists had high prevalence of both MS and obesity. Smoking, alcohol drinking, the transition from pastoral dietary pattern to urban dietary pattern and inadequate physical activity served as associated factors for MS and its components.