Is China facing an obesity epidemic and the consequences? The trends in obesity and chronic disease in China

Background: Over the past two decades, China has enjoyed impressive economic development, and her citizens have experienced many remarked changes in their lifestyle. These changes are often associated with an increase in obesity and chronic disease. Methods: In this meta-analysis, based on nationally representative data, we studied the current prevalence of obesity and the trends in obesity, mortality and morbidity in China. Results: Between 1992 and 2002, the prevalence of overweight and obesity increased in all gender and age groups and in all geographic areas. Using the World Health Organization body mass index cut points, the combined prevalence of overweight and obesity increased from 14.6 to 21.8%. The Chinese obesity standard shows an increase from 20.0 to 29.9%. The annual increase rate was highest in men aged 18-44 years and women aged 45-59 years (approximately 1.6 and 1.0% points, respectively). In general, male subjects, urban residents, and high-income groups had a greater increase. With the increase in overweight and obesity, obesity-, and diet-related chronic diseases (e.g., hypertension, cardiovascular disease (CVD), and type 2 diabetes) also increased over the past decade and became a more important preventable cause of death. Hypertension increased from 14.4% in 1991 to 18.8% in 2002 in adults; in older adults aged 35-74 years, it increased from 19.7 to 28.6%. Between 1993 and 2003, the prevalence of CVD increased from 31.4 to 50.0%; diabetes increased from 1.9 to 5.6%. During 1990-2003, although total mortality rate (per 100 000) decreased, overall the mortality rate and contribution (as percentages) to total death of obesity-related chronic disease increased, in particular, in rural areas. Mortality rate (per 100 000) of CVD increased from 128 to 145 and its contribution to total death, 27 to 32%, in rural areas; the figures decreased slightly in urban areas. The mortality rate of 'nutrition, endocrinology and metabolism-related disease' (NEMD) increased in both rural and urban areas between 1990 and 2000, 8.0 to 10.6 and 4.9 to 5.3, respectively. The current prevalence of hypertension, dyslipidaemia, metabolic syndrome, and diabetes among Chinese adults is approximately 20, 20, 15, and 3%, respectively. Conclusion: The prevalence of overweight and obesity and obesity-related chronic diseases have increased in China in the past decade. Our findings provide useful information for the projection of future trends and the formulation of national strategies and programmes that can address the challenges of the growing obesity and chronic disease epidemic.