| Chapter 2: | Background |
|
|
This is a limited free preview of this book. Please buy full access.
The prevalence of chronic diseases was higher in urban areas than in rural areas. Diabetes prevalence was very low before 1990, approximately 1.5% or less, even in the urban populations (14). A study (15) involving 19 provinces and more than 200,000 adults conducted in 1994 demonstrated an age-standardized prevalence of 2.3% for diabetes and 2.1% for impaired glucose tolerance (IGT). A recent survey in 2000–2001 showed that prevalence of diabetes increased to 5.5% in adults aged 30 to 75 years (16). China is predicted to contribute almost 38 million people to the global burden of diabetes in the year 2025 (17).
There was a modest increase in hypertension rate between 1991 and 1997 among Chinese adults (1). In 1997 the prevalence of hypertension was about 19.0%. Although the prevalence was higher in urban adults than in rural adults (21% vs.15.4% in males, 18.4% vs.14.6% in females), it increased more rapidly in rural areas compared with that in urban areas. In 2000 the reported prevalence became similar in urban and rural area (29% vs. 28%) for adults aged 30 to 74 years (18).
The overall death rate decreased between 1974 and 1984, but after 1980 it rose in urban areas. This shift was concurrent with the increase in diet-related noncommunicable diseases, circulatory system diseases, and cancer. The 1999 mortality of infection and parasite diseases in rural areas was one-seventh of the rate in 1974, but the mortality of diabetes in urban areas increased five-fold in 1999, compared with that in 1974 (15.4 vs. 3.4 per 100,000). In 1995 China’s costs of undernutrition and costs of diet-related noncommunicable diseases were of similar magnitude, but there is expected to be a rapid increase in the prevalence and costs of diet-related noncommunicable diseases by 2025 (19).
2.1.2 The Metabolic Syndrome
The metabolic syndrome—the so-called insulin resistance syndrome or syndrome X—is defined as a pattern of metabolic disorders including central obesity, insulin resistance, hyperglycemia, hypertension, and dyslipidemia (20).