In 2010, the China National Diabetes and Metabolic Disorders Study Group and the International Diabetes Federation reported that 93 million Chinese adults have diabetes, comprising 9.7% of the Chinese adult population.1,2 The China National Diabetes and Metabolic Disorders Study Group categorized those 93 million adults into two groups: 49.3 million living in urban areas and 43.1 million living in rural areas. The prevalence of diabetes was higher in urban residents (11.4%) versus rural residents (8.2%.).1 From the same study, it is thought that an additional 148.2 million Chinese are prediabetic and will become diabetic if they do not change their eating habits.1 These statistics are recognized to be an underestimation since there are inadequate public health records in rural China. It is thought that by 2030, there will be an estimated 500 million diabetics in China.2 These statistics characterize diabetes to be a major public health problem and in the future, diabetes will play a role in the projected increased demand for health care services in China.
Public Awareness of Diabetes in China
According to the International Diabetes Federation, in China, 60.7% of the diabetics are undiagnosed, and this is likely to result from the combination of poor public awareness, poor health keeping records and limited opportunities for diagnosis.2 For many Chinese in rural areas, the diagnosis of Type 2 diabetes mellitus occurs when they enter the health care system for other reasons such as heart attack or stroke. Thus, the longer period of time that people are undiagnosed, the more likely their blood glucose levels will be poorly controlled. Then, it will be more likely that they will have diabetic complications, affecting vision, kidney or cardiovascular problems. There is room for improvement for the increased diagnosis of diabetes and treatment. Accessible care exists in the urban but not the rural areas. Thus, in China, there needs to be public health and education outreach to its citizens about diabetes and medical intervention.
Unhealthy lifestyles such as smoking, excessive alcohol consumption, physical inactivity and imbalanced diets are contributory to chronic non-communicable diseases such as diabetes, coronary heart disease stroke and cancer. The increased incidence of these diseases has risen in the last 20 years.3, 4 In an article by Liu Z et al, the authors created a multi-centered study involving 1524 patients with Type 2 diabetes mellitus from outpatient departments of 15 general hospitals in 4 major cities of China, Shanghai, Beijing, Guangzhou and Chendu, to evaluate the complications from diabetes.4 The study was conducted from March to July 2007, using face to face interviews and a questionnaire. Of the 1524 patients, 792 patients had one complication from diabetes (52%). 509 (33.4%) had macrovascular complications and 528 (34.7%) had microvascular complications.4 The prevalence of cardiovascular complications (30.1%) far outweighed the other complications of cerebrovascular conditions (6.8%), neuropathy (17.8%), nephropathy (10.7%), ocular lesions (14.8%) and foot disease (0.8%). However, these findings were found by questionnaire only.4 There may have been more laboratory abnormalities but clinical laboratory results was not one of the study criteria. The mean HbA1c in diabetic patients with chronic complications was 8.2% . Of note, 63% of the subjects with Type 2 diabetes-related complications had poor glycemic control with HbA1c ≥ 7.5%.4
The China National Nutrition and Health Survey in 2002 found that the complications from diabetes were prevalent among urban Chinese Type 2 diabetes mellitus patients.5 More than half of the patients suffered from at least one chronic complication, almost one quarter had 2 or more complications.5
Liu et al., in their 2002 study, reported the prevalence of Type 2 diabetes mellitus and impaired fasting glucose; and the association between diabetes and being overweight/obese in Chinese adults.5 The authors compared the results with those from the US National Health and Nutrition Examination Survey 1999-2002. Data were collected from adults ages 20 years and older who participated in the China National Nutrition and Health Survey in 2002 (n=47,729). Diabetes and impaired fasting glucose were defined by the American Diabetes Association 2009 criteria.6, 7 The prevalence of diabetes was 2.7% and for impaired fasting glucose 4.9% respectively, among the Chinese adults in the Liu and Wang study. Men and women had a similar prevalence of diabetes but men had a significantly higher prevalence of impaired fasting glucose. The prevalence of diabetes in urban Chinese was 3 times higher (6.1%) than those who live in rural areas (1.9%). Similarly, the prevalence of impaired fasting glucose was 1.5 to 2 times higher for urban versus rural areas. The prevalence of diabetes among Chinese women and young (20-39 years old) and middle aged (40-59 years old) adults who lived in large cities was similar to prevalence of diabetes in the US population. According to Liu et al., increased age with higher body mass index (BMI, kg/m2) is correlated with higher incidence of diabetes. In individuals ages 60 years and over with a BMI greater than 30.0, the prevalence of diabetes is 18% versus 15% in individuals ages 40-50 years. The prevalence of diabetes in individuals aged 20-39 years with BMI over 30.0 is 7%. Contributing Factor
Researchers attribute the recent increase of diabetes to China’s urbanization and westernization, which has led to sedentary life styles and changes in eating habits. There is increased consumption of meats, processed foods, and sweets – deviating from the traditional Chinese diet of vegetables and rice. Studies have also shown that there are more diabetics living in urban versus rural areas.3, 4
METABOLIC SYNDROME (now 8,9)
The metabolic syndrome includes the clinical characteristics of obesity, abnormal fasting blood glucose, dyslipidemia and elevated blood pressure. The importance of metabolic syndrome has been useful as a diagnostic and clinical tool for identifying patients who are at risk for diabetes and cardiovascular disease. There is controversy about the inclusion of obesity and insulin resistance as criteria for the metabolic syndrome. Asians are thought to have greater body fat deposition than Caucasians and thus have more cardiovascular risks than Caucasians at a given BMI.8 Thus, these racial factors raise a concern that the metabolic syndrome criteria for Caucasians may not apply to Asians. Consequently, the risk for diabetes, cardiovascular disease and mortality may be underestimated for Asians. The International Diabetes Federation proposed a new definition of the metabolic syndrome that uses ethnic specific central obesity criteria as a prerequisite for diagnosis of the syndrome.9
Metabolic Syndrome Criteria International Diabetes Federation (IDF): 2006
|According to the new IDF definition, for a person to be defined as having the metabolic syndrome they must have:|
|Europid Male||Europid Female||Asian Male||Asian Female|
|Central obesity||≥37in (94cm)||≥31.5in (80cm)||≥35.4in (90cm)||≥31.5in (80cm)|
|Plus any 2 of the following 4:|
|Raised triglycerides||≥ 150mg/dL|
|Reduced HDL cholesterol||< 40mg/dL (males) <50mg/dL (females)|
|Raised blood pressure||Systolic BP ≥ 130 mmHg Diastolic BP ≥ 85 mmHg|
|Raised fasting plasma glucose||≥100 mg/dL|
http://www.idf.org/webdata/docs/MetS_def_update2006.pdf Adult Treatment Panel (ATP) III: 2004
|Any 3 of the following:|
|Abdominal obesity (waist circumference)||M: >40inches (102cm) F: >35 inches (88cm)|
|HDL cholesterol||M: <40mg/dL F: <50mg/dL|
|Blood pressure||≥130/≥85 mmHg|
|Fasting glucose||≥100 mg/dL|
In a study of urban Beijing residents, the prevalence of the metabolic syndrome is 13.2%.10 In another study of 15, 540 Chinese adults, ages 35 to 74 years, in 2000 to 2001, the incidence of the metabolic syndrome was 9.8% in men and 17.8 % in women.9 The age-standardized prevalence for being overweight, BMI > 25, was 26.9% in men and 31.1% in women.11 The metabolic syndrome is common in elderly Chinese as with increasing age, there is increasing incedence of diabetes and hypertension.
In China, the increase in Type 2 diabetes mellitus and metabolic syndrome is related to obesity. Many Chinese may not appear obese and have BMI that falls in the normal range for Caucasians but it is recognized that in Asian populations, Asians have a greater tendency to develop diabetes at a modest level of BMI and waist circumference.12, 13, 14
Despite controversies in the definition of the metabolic syndrome, its criteria serve as important markers for clinicians in assessing risk for diabetes in the Asian population. Thus, the metabolic syndrome criteria may play a greater role in the assessment of Asian metabolic and cardiovascular health in the future.
Shanghai’s Fudan University study showed in 2009 that annual direct medical and direct nonmedical costs per case averaged $1320.90 USD and $180.80 USD respectively. Per case, the mean annual indirect costs of Type 2 diabetes mellitus and its complications were estimated to $206.10 USD. Based on case numbers in 2007. The direct medical costs of Type 2 diabetes mellitus and it complications were estimated to be $26 billion USD in 2007. In 2030, these same costs were projected to be USD 47.2 billion.16
In a Chinese study of four urban centers, diabetic patients with two complications doubled direct medical costs and in patients with four or more complications paid 6, 7 more money was spent than those without complications.17 The average annual direct medical cost per patient in this study was estimated to be $4800 (RMB) or $10,164 (RMB) mean expenditure. There is a difference between annual direct medical costs for patients with ($6056 RMB) or without complications ($3583 RMB). Patients who had combined microvascular/macrovascular disease spent $7600 RMB vs. those patients with only macrovascular disease ($6000 RMB), vs. microvascular disease ($5364) vs. those without both diseases ($3600 RMB).
In 2011, the International Diabetes Federation stated that there are 4.6 million deaths due to diabetes each year worldwide and one person is now dying form the disease every 7 seconds. The annual health care spending for diabetes in the world is $465 billion.15 The cost of healthcare will rise as more diabetes is diagnosed in China.
- Yang W, Lu J, Weng J, et al. Prevalence of Diabetes among Men and Women in China, New England Journal of Medicine 2010; 362: 1090-1101
- International Diabetes Federation website (http://www.idf.org/node/4371/ accessed Sept 5, 2011)
- Yang ZY, Yang Z, Zhu L, Qiu C. Human Behaviors Determine Health: Strategic Thoughts on the Prevention of Chronic Non-communicable Diseases in China. International Journal of Behavioral Medicine 2011, Aug 21. (http://www.ncbi.nlm.nih.gov/pubmed?term=diabetes%20china%20%2B%20int%20j%20behav%20med%202011. Accessed Sept 5, 2011)
- Liu Z, Fu C, Wang W, Xu B. Prevalence of chronic complications of T2DM in outpatients – a cross sectional hospital based survey in urban China. Health Quality of Life Outcomes. 2010; 8:62
- Liu S, Wang W, Zhang J, et al. Prevalence of diabetes and Impaired Fasting glucose in Chinese adults , China National Nutrition and Health Survey, 2002. Preventing Chronic Disease 2011 Jan; 8(1); A14 Epub 2010 Dec 15
- American Diabetes Association. Diagnosis and Classification of Diabetes Mellitus. Diabetes Care, 32(1): January 2009
- American Diabetes Association. Summary of Revisions for the 2009 Clinical Practice Recommendations. 32(1) January 2009
- National Institutes of Health. Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III). Executive Summary. NIH Publ. no. 01-3670. Bethsda, MD: National Institutes of Health, National Heart, Lung and Blood Institute 2001.
- Isomaa B, Almgren P, Tuomi T, et al. Cardiovascular morbidity and mortality associated with the metabolic syndrome. Diabetes Care 2001; 24: 683-9.
- Li Zy, Xu GB, Xia TA. Prevalence rate of metabolic syndrome and dyslipidemia in a large professional population in Beijing. Atherosclerosis 2006; 184:188-92
- Gu D, Reynolds K, Wu X et al. Prevalence of the metabolic syndrome and overweight among adults in China. Lancet 2005; 365:1398-405
- Zhou BF. Effect of body mass index on all-cause mortality and incidence of cardiovascular diseases – report for meta-analysis of prospective studies open optimal cut-off points of body mass index in Chinese adults. Biomed Environ Sci 2002; 15: 245-52.
- Moon OR, Kim NS, Jang SM et al. The relationship between body mass index and the prevalence of obesity related diseases based on the 1995 National Health Interview Survey in Korea. Obes Res 2002; 3:191-6.
- Kim Y, Suh YK, Choi H. BMI and metabolic disorders in South Korean adults: 1998 Korean National Health and Nutrition Survey. Obes Res 2004; 12:445-53.
- (http:// mailview.bulletinhealthcare.com/mailview.aspx?m=2011091401ccf&r=5182141-ca46).
- So WY, Raboca J, Sobrepena L et al. JADE Program Research Team. “Comprehensive risk assessments of diabetic patients from seven Asian countries: The Joint Asia Diabetes Evaluation (JADE) program. Journal of Diabetes. 2011 Jun; 3(2):109-18
- Wang, W, Fu, CW, Pan, CY, Chen W et al. How do Type 2 Diabetes Mellitus-Related Chronic Complications Impact Direct Medical Cost in Four Major Cities of Urban China? Value in Health 2009. 12 (6):923-929.