Current scenario of diabetes in India

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1 Journal of Diabetes 1 (2009) REVIEW ARTICLE Current scenario of diabetes in India Ambady RAMACHANDRAN and Chamukuttan SNEHALATHA India Diabetes Research Foundation and Dr A. Ramachandran s Diabetes Hospitals, Chennai, India Correspondence Ambady Ramachandran, Dr A. Ramachandran s Diabetes Hospitals, 28 Marshall s Road, Egmore, Chennai , India. Tel: Fax: ramachandran@vsnl.com Received 5 June 2008; revised 2 September 2008; accepted 27 October doi: /j x Abstract India, a country experiencing rapid socioeconomic progress and urbanization, carries a considerable share of the global diabetes burden. Studies in different parts of India have demonstrated an escalating prevalence of diabetes not only in urban populations, but also in rural populations as a result of the urbanization of lifestyle parameters. The prevalence of prediabetes is also high. Recent studies have shown a rapid conversion of impaired glucose tolerance to diabetes in the southern states of India, where the prevalence of diabetes among adults has reached approximately 20% in urban populations and approximately 10% in rural populations. Because of the considerable disparity in the availability and affordability of diabetes care, as well as low awareness of the disease, the glycemic outcome in treated patients is far from ideal. Lower age at onset and a lack of good glycemic control are likely to increase the occurrence of vascular complications. The economic burden of treating diabetes and its complications is considerable. It is appropriate that the Indian Government has initiated a national program for the management and prevention of diabetes and related metabolic disorders. Lifestyle modification is an effective tool for the primary prevention of diabetes in Asian Indians. The primary prevention of diabetes is urgently needed in India to curb the rising burden of diabetes. Keywords: Asian Indians, burden of diabetes, diabetes, prevalence of diabetes, prevention of diabetes. Introduction Diabetes is the most common non-communicable disease globally. The estimated number of adults with diabetes in 2007 was 246 million; 1 of these, 80% live in developing countries, the largest numbers on the Indian subcontinent and in China. 1 Approximately 85 95% of all cases of diabetes are type 2 diabetes and the worldwide explosion of this disorder is a major health care burden. It is estimated that nearly 380 million adults worldwide will have diabetes by India has 41 million diabetics and this number is expected to increase to 70 million by The increased number of diabetics in India is likely to be due to a significant increase in the incidence of type 2 diabetes, caused by unprecedented rates of urbanization, which results in environmental and lifestyle changes. According to World Health Organization (WHO) estimates, the urban population in developing regions will increase from 1.9 billion in 2000 to 3.9 billion in It is estimated that, by 2030, nearly 46% of India s population will be living in urban areas. 3 Chronic diseases, such as diabetes and cardiovascular disease (CVD), pose a primary challenge for the health care system. 3 India is the second most populous country, with considerable diversity in caste, religion, habitat, socioeconomic status, lifestyle, and food habits. Although several infectious and parasitic diseases have been controlled successfully in India, non-communicable diseases are becoming increasingly common, resulting in an enormous burden on the health care system. Significant economic improvements have occurred in India, 4 but the large population creates difficulties for the effective reduction of poverty, malnutrition, and the provision of health care to all. India, China, 18 ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd

2 A. RAMACHANDRAN and C. SNEHALATHA Diabetes in India and Pakistan contribute 21%, 12%, and 5%, respectively, to the annual increase in the global population. 3 Epidemiology of diabetes: changing trends Diabetes mellitus (DM) was known to the ancient Indian physicians Charaka and Sushruta ( bc), who described differences in the clinical picture of patients with Madhumeha (passing a large volume of sweet urine): some patients were very lean and had severe polyuria, thirst, and dehydration, whereas others were stout, ate excessive amounts of food, and were sedentary. These two groups were later classified as insulin dependent (or type 1) and non-insulindependent (or type 2) diabetes, respectively. The development of uniform criteria for the diagnosis and classification of diabetes 5 has helped to compare data from different parts of the world. It has also helped in making global estimates of the prevalence of diabetes, as well as projections for the future. 1 3 A multicenter epidemiological study performed by the Indian Council of Medical Research (ICMR) in the early 1970s reported that the prevalence of diabetes in the urban and rural populations 14 years of age was 2.3% and 1.5%, respectively. 6 Since then, over the period , studies from different parts of India have reported a 10-fold increase in the incidence of diabetes in the urban area (from 1.2% in 1971 to 12.1% in 2000) Although WHO criteria for the diagnosis and classification of diabetes 25 had been in use since 1980, many of these reports are not strictly comparable owing to variations in sample selection, diagnostic criteria, and differences in the age of the people screened. 26 A series of epidemiological studies performed in Chennai, southern India, showed an increasing prevalence of diabetes and impaired glucose tolerance (IGT). 10,14,15,17,23,24 This trend was considered to be a phenomenon of the urban environment because many studies showed wide urban rural differences. Studies over the period , using standardized WHO 5,27 or American Diabetes Association (ADA) criteria, 28 have demonstrated that the prevalence of diabetes in India has increased from 5% to 15% among urban populations, from 4.2% to 6.2% in semi-urban populations, and from 2% to 5% in rural populations, with wide regional disparities related to urban and rural settings. 26 Urban areas Most studies since 2000 have used either recent WHO criteria 27 or ADA criteria. 28 However, there was considerable disparity in the age of the subjects involved in the studies and many studies reported only crude prevalence rates (Table 1). The highest prevalence of diabetes and or IGT was reported for the southern state of Kerala, which had undergone widespread and rapid urbanization. 19,29 The lowest prevalence rates for diabetes and IGT among an urban Indian population were found in Kashmir 18 (north India), with crude prevalence rates (based on WHO criteria) of 6.1% and 8.1%, respectively. National data A national urban diabetes survey performed in six major cities in representative samples of subjects Table 1 Prevalence of diabetes in urban India since 2000 Region Year Age of subjects (years) Criteria Prevalence* (%) Diabetes IGT IFG National Ramachandran et al K + F + PG Reddy et al K + F Sadikot et al K + F + PG Northern India Delhi K + F + PG Jaipur K + F Delhi K + F + PG Southern India Chennai K + F + PG Chennai K + F + PG Kerala K + F + PG Chennai K + F + PG *Italicized values are age-adjusted prevalence values; this study was conducted in industrial workers (men only). K, known diabetes; F, fasting plasma glucose; PG, 2-h post-glucose. ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd 19

3 Diabetes in India A. RAMACHANDRAN and C. SNEHALATHA 20 years of age and using WHO criteria 27 showed age-standardized prevalence rates of diabetes and IGT of 12.1% and 14.0%, respectively (Table 1). The prevalence of diabetes varied from 9% to 16.6% in different regions, with the southern region of India having higher prevalence rates than other parts of India. 24 Another national survey performed by Reddy et al. 30 in in industrial workers and families (mean age 40 years) reported an age-adjusted prevalence of diabetes of 8.4%. Known cases of diabetes and new cases detected on screening with fasting plasma glucose were included. However, the total prevalence may be much higher, because 2-h glucose values are more sensitive than fasting glucose levels in detecting diabetes among Asian Indians. 31 The Prevalence of Diabetes in India Study (PO- DIS) 32 reported a low prevalence of diabetes (5.9%) compared with previous studies because of different sampling criteria and population sizes. However, the final estimated prevalence of diabetes was similar (33 million) to that derived from earlier studies. North India In the national urban diabetes survey, 24 the prevalence of diabetes and IGT in Delhi was found to be 11.6% and 8.6%, respectively. In a later study performed in 2005 in northern parts of India, the crude prevalence of diabetes among men working in industries was found to be 15%. 33 A large proportion (37%) of these subjects had either IGT or impaired fasting glucose (IFG). A 2003 study from Jaipur using ADA criteria 28 reported an age-standardized prevalence of diabetes of 8.6% 34 (Table 1). Figure 1 Changing prevalence of diabetes ( ) and impaired glucose tolerance (h) in urban southern India. South India A series of epidemiological studies from southern India have shown a trend for the increased prevalence of diabetes since All studies have used WHO criteria 27 and most have reported age-standardized prevalence (Table 1). Recent studies in Chennai, in southern India, made the interesting observation of a rapid increase in diabetes with a marked reduction in the prevalence of prediabetic conditions. In Chennai, the prevalence of diabetes was found to be 13.5% in 2000, 24 which increased to 14.3% in 2004, 35 and increased further in 2006 to 18.6%. 36 Interestingly, the prevalence of IGT had decreased from 16.8% in to 10.2% in and further still to 7.4% in In 2006, the prevalence of diabetes and IGT in the town of Kancheepuram were 16.7% and 4.3%, respectively. 36 The escalating prevalence of diabetes from 2000 to 2006 is an indication of a rapid conversion of susceptible individuals, especially those with IGT and or IFG, to diabetes (Fig. 1). This hypothesis is supported by the rather unexpected decrease in the prevalence of IGT and IFG over the same period of time. 36 Asian Indians with IGT have a high conversion rate to diabetes (55% in 3 years). 37 In the southern state of Kerala, where the crude prevalence of diabetes is 19.5%, IGT was detected in only 4.1% of the population. 29 These figures are in agreement with recent reports from the neighboring state of Tamilnadu. 35,36 A nation-wide survey of risk factors of non-communicable diseases (NCD) in individuals aged 15 years performed in showed significant urban rural differences in self-reported (known) diabetes. 38 The highest prevalence of self-reported diabetes was found in urban areas (7.3%), followed by peri-urban slum areas (3.2%). The high rates of diabetes were correlated with body mass index (BMI) and abdominal obesity. 38 Increased awareness and screening, and the earlier detection of glucose intolerance, will result in higher rates of known diabetes. The total prevalence, calculated as the sum of known and newly diagnosed cases following screening, is unlikely to be affected by these factors. Rural areas Presently, India is largely a rural nation, but according to WHO estimates, by 2030 urbanization is expected to reach 46%. 3 Therefore, in the future, rural areas that are currently undergoing rapid 20 ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd

4 A. RAMACHANDRAN and C. SNEHALATHA Diabetes in India migrant Indian populations in many parts of the world. 44 Genetic susceptibility Figure 2 Changing prevalence of diabetes and impaired glucose tolerance (IGT) in rural populations in southern India from 1989 ( ), through 2003 ( ), and to 2006 (h). urbanization could make a considerable contribution to the overall diabetic population. Improved socioeconomic conditions in rural India have resulted in an explosion of metabolic disorders, such as diabetes, CVD, and hypertension. 36,39 Figure 2 shows temporal changes in the prevalence of diabetes and IGT over the period Similar trends have been described for neighboring countries, such as Thailand, Malaysia, Bangladesh, and Pakistan. 1 Two studies in urbanizing rural areas found an IGT: diabetes ratio of >1, 39,40 indicating a large pool of prediabetic subjects. In 2006, the prevalence of diabetes in peri-urban villages (PUV) was 9.2%, 36 whereas the prevalence of IGT had decreased from 7.2% in to 5.5% in (Fig. 2). A national survey conducted in 2005 found that the self-reported prevalence of diabetes (known diabetes) in rural areas was 3.1%. 38 Another two recent studies in rural areas of southern India reported a high prevalence of diabetes and IFG. 41,42 Both these studies tested capillary fasting glucose. In rural Tamilnadu, the crude prevalence among adults of diabetes and IFG is currently 5.1% and 13.5%, respectively. 41 In Andhra Pradesh, Chow et al. 42 reported a high crude prevalence of diabetes (13.2%; 6.4% known) and IFG (15.9%) in These are probably the highest prevalence rates reported for a rural area. Until 2000, the prevalence of diabetes in rural areas had been reported to range from 1.5% to 4.0%; 26 in 2006, Deo et al. reported a rural prevalence of diabetes of 9.3% in western India. 43 Risk factors for diabetes Indians have a number of characteristic features that make them highly susceptible to diabetes. High racial predisposition towards diabetes is evident from the studies in native Asian Indians, as well as in Studies in India and abroad have shown that Asian Indians have a strong genetic predisposition to diabetes, which is easily unmasked under adverse environmental conditions. 45 Nearly 75% of type 2 diabetic patients in India have a first-degree family history, indicating a strong familial aggregation in this population. 46 Environmental factors Asian Indians are susceptible to risk factors such as age, general adiposity (BMI), and central adiposity, measured either as waist circumference (WC) or as the waist:hip ratio (WHR) at lower threshold levels. 47,48 The presence of central adiposity despite a lean BMI, a high percentage of body fat compared with Europeans, and hyperinsulinemia suggesting the presence of insulin resistance are other features characteristic of the Asian Indian population Age Asian Indians develop diabetes at a younger age, at least years earlier than the Caucasian population. 47,48 The national urban diabetes survey in India showed that more than 50% of diabetic patients had onset at less than 50 years of age. 24 Indians show a significantly higher age-related prevalence of diabetes compared with the Caucasian population in the US. 52 Indians have a several-fold higher prevalence of diabetes for all age groups compared with European populations, as reported by the International Diabetes Epidemiology Group. 48 It has also been shown that the risk of age-adjusted diabetes starts to increase for both sexes over the BMI range kg m Recent data from our studies in urban and rural areas of India illustrate the trend towards a decrease in the age of the diabetic population. The proportion of diabetic patients younger than 40 years of age has increased considerably over a decade 36 (Table 2). Data collected from different studies are comparable because the criteria for sample selection, diagnosis, and classification of glucose intolerance are similar. Another study from southern India in subjects years of age that used WHO criteria 27 showed that diabetes was prevalent in 3.7% of the urban population and in 2.1% of the rural population. 55 The prevalence of IGT was higher: 18.9% and 14.3% in urban and rural populations, respectively. ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd 21

5 Diabetes in India A. RAMACHANDRAN and C. SNEHALATHA Table 2 Temporal changes in the age of diabetic patients in southern India * Year Age (years) % Diabetics <44 years of age * City ± ± 11.3* 35.7 Periurban village ± ± 10.8* 34.8 * Mean (±SD) age of current diabetic patients and the proportion of patients younger than 44 years of age are shown. *P < 0.01 compared with the previous year (t-test); P < 0.01 compared with the previous year (v 2 test). Adiposity in Indians: general adiposity (BMI) Asian Indians generally have a lower BMI than many other ethnic groups, but the association between BMI and glucose intolerance is as strong as in any other population. 24 The risk of diabetes (odds ratio) was significant for urban Indian populations with a BMI of >23 kg m This has been confirmed by studies from other parts of India, 21 as well as in studies of migrant Indians 54 and in other Asian populations. 56 According to WHO recommendations, a BMI of kg m 2 is considered healthy for Asian populations. 56 Insulin resistance is one of the major etiological factors for diabetes and the risk association between obesity and diabetes is mediated through insulin resistance. Figure 3 shows temporal changes in the prevalence of obesity (BMI=25 kg m 2 for Indians) on the basis of results from epidemiological studies. 36,40 Abdominal adiposity Abdominal adiposity is an important risk factor for diabetes and insulin resistance. The cut-off values for a normal WC in male and female Asian Indians are 85 and 80 cm, respectively, whereas the cut-off values for WHR are 0.89 and 0.81, respectively. 53 Visceral fat increases the risk of diabetes and hyperlipidemia by favoring insulin resistance. By measuring visceral and subcutaneous abdominal fat areas in non-diabetic southern Indians, we showed that insulin resistance was also associated with subcutaneous fat and, therefore, that subcutaneous fat is not innocuous. 57 Abdominal obesity is a key component of the metabolic syndrome. Racial susceptibility to insulin resistance and metabolic syndrome has been demonstrated and Asian Indians are highly susceptible to both. 50,51,58 The existence of high insulin resistance Figure 3 Changes in the prevalence of obesity (body mass index 25 kg m 2 ) in (a) city and (b) peri-urban villages in 2000 ( ), 2003 ( ), and 2006 (h). *P < compared with 2000; P = compared with despite a lower BMI could be explained by the upper body adiposity in Asian Indians. Studies in migrant Asians comparing body fat topography with Caucasians have confirmed these findings. 52,54 We observed a significantly lower BMI in the rural compared with the urban population, but both groups had a similar WHR. 14 This probably indicates a racial tendency in the population for the preferential abdominal deposition of fat. Body fat percentage It has also been noted that for a given BMI, Asian Indians have higher fat percentage compared with Caucasians. 52 Higher insulin resistance and an increased risk of diabetes may be attributed, in part, to this feature. 22 ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd

6 A. RAMACHANDRAN and C. SNEHALATHA Diabetes in India Insulin resistance Asian Indians are highly insulin resistant compared with other ethnic groups and apparently healthy young Asian Indians exhibit the presence of insulin resistance. 52,58 Moreover, Asian Indians exhibit several distinct differences in features associated with insulin resistance. Recently, a comparative study in northern European, American, and Asian Indian subjects with and without diabetes showed that Indians, although highly insulin resistant, had no evidence of subnormal mitochondrial function. 59 Conversely, they had higher rate of ATP production. Levels of intramuscular triglycerides (IMTG) were higher in non-diabetic Indians compared with nondiabetic Americans. However, IMTG levels were similar in non-diabetic and diabetic Indians, probably indicating that, in this population, IMTG levels have different associations with insulin resistance and type 2 diabetes. A study in native Asian Indians 60 and another in migrant south Asians in the UK 61 found that IMTG was not associated with insulin resistance or obesity. In the Asian subjects, muscle triglyceride did not appear to mediate the effects of obesity on insulin sensitivity, whereas plasma triglycerides and the WHR showed the strongest associations with insulin sensitivity. 61 Impact of urbanization Urbanization is occurring rapidly on the Indian subcontinent. Lifestyle changes involving major changes in dietary patterns, decreased physical activity due to improved transportation, the availability of energy saving devices, and the high level of mental stress are associated with modernization. Weight gain and decreased energy expenditure contribute further to the existing insulin inertia. Lifestyle transitions in the rural population have a significant effect on the prevalence of obesity and glucose intolerance. 39,40 The prevalence of diabetes has increased from 2.4% in to 9.3% in Important risk factors associated with this increase are a lack of physical activity and increased upper body adiposity. Similar observations were reported in Singapore 62 and Malaysia 63 during the stages of urbanization. National and regional heterogeneity in the occurrence of diabetes may be more strongly related to recent environmental events rather than to genetic factors, which change very slowly. 64 The present generation has easy access to agricultural, industrial, and technological devices that are already developed, unlike older generations. This may explain, in part, the sudden spurt of lifestyle disorders in urban populations in developing countries. 1 Stress factors The impact of stress, both physical and mental, is very strong on diabetogenesis, especially in those with a strong genetic predisposition. 65 A clinic-based prospective study clearly showed the effect of stress on diabetes. 66 The impact of stress, the lack of physical activity, and unhealthy diet habits are observed frequently among the present, economically thriving, urban professionals. 67 In addition, there is a high prevalence of lifestyle disorders in this group. Cardiometabolic risk factors Indians have higher rates of cardiometabolic risk factors, such as abdominal obesity, dyslipidemia (especially low high-density lipoprotein cholesterol and hypertriglyceridemia), and insulin resistance. 24,36,68 70 The prevalence of abdominal obesity is higher than that of general obesity. The prevalence of cardiometabolic risk factors is strongly associated with obesity, particularly abdominal obesity. These associations explain the high prevalence of metabolic syndrome in the Indian population, as defined by any of the existing criteria. Abdominal obesity and general obesity have been shown to exhibit familial inheritance in the southern Indian population. 71 A recent urban and rural study in Tamilnadu illustrated the high prevalence of these risk factors in both populations. 36 The presence of diabetes itself is known to increase the CVD risk by two- to fourfold. Studies on cardiometabolic risk factors in children and adolescents have been published from different parts of the world. 72 Most studies were performed in obese subjects. A large percentage of non-obese Asian Indian teenagers show evidence of insulin resistance and other cardiometabolic abnormalities (68%). 73 The prevalence (85%) and clustering of these abnormalities increased with the presence of obesity. Type 2 diabetes in children has become more common among Indians, both in India 74 and in migrant Indian populations. 75 A strong association between overweight and the increased prevalence of diabetes was noted. 74,75 Overweight, in turn, was correlated with a lack of physical activity and with a high socioeconomic background. 74 ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd 23

7 Diabetes in India A. RAMACHANDRAN and C. SNEHALATHA Chronic complications of diabetes The economic burden of diabetes involves the chronic care of diabetics, which escalates many-fold when vascular complications develop. There is a lack of population-based data regarding the prevalence of micro- and macrovascular complications from different parts of the developing world. It has been reported that retinopathy is prevalent in approximately 30% of type 2 diabetics and that its prevalence is significant in the Asian and Pacific Island nations. 76 A study in south India reported a prevalence of diabetic retinopathy of 34.1%. 77 High rates of CVD have been reported in India 78,79 and in other Asian countries, as well as in migrant Indian populations. 80 Data from Chennai show that the prevalence of complications in type 2 diabetes are as follows: retinopathy 23.7%; nephropathy 5.5%; peripheral neuropathy 27.5%; CVD 11.4%; peripheral vascular disease 4.0%; and stroke 0.9%. The prevalence of hypertension is also high (38.0%) 78 and the prevalence of coronary heart disease in Indians may be as high as in immigrant Indians. 81 We noted that among the patients admitted with acute coronary syndrome, nearly 84% had abnormal glucose tolerance. 82 Asian Indians have a low prevalence of peripheral vascular disease compared with the Caucasian population (9.3%). 78,83 Although the prevalence of peripheral vascular disease is low, neuropathy is very common and is an associated risk factor for foot infections, which often tend to recur. The prevalence of diabetes in economically poor sections of the urban population is lower than in the high-income group, but owing to a lack of good glycemic control, the occurrence of vascular complications is higher in the former group. 84 Cost of treating diabetes The costs involved in the care and management of diabetes are considerable for both the individual and the health care system. Caring for diabetics involves a direct cost borne by the affected individuals, their families, and healthcare authorities. Indirect and intangible costs are larger. The indirect costs result from lost production as a result of frequent absence from work, an inability to work because of disability, premature retirement, and even premature mortality as a result of complications. Intangible costs are those that reduce the quality of life, because of pain, anxiety and stress. A recent study showed that total annual expenditure by patients on diabetes care was, on average, INR (US$227) in urban areas and INR 6260 (US$142) in rural areas. 85 A secular increase of 113% was observed in the total expenditure between 1998 and 2005 in the urban population. Low-income groups spent a higher proportion of their income on diabetes care (34% and 27% for urban poor versus rural poor, respectively) without subsidies. 85 The medical costs incurred by a person with diabetes are two- to fivefold higher than those incurred by people without diabetes. The average expenditure per patient per year would be a minimum of INR 4500 (approximately US$120). Therefore, the estimated annual cost of diabetes care would be approximately million rupees. Prevention of diabetes India needs to implement preventive measures to reduce the burden of diabetes, because it poses a medical challenge that is not matched by the budget allocations for diabetes care. A genetic environmental interaction leads to the final expression of the disease. Although the genetic component cannot be corrected, many of the environmental factors are modifiable. Obesity, diet, and physical activity are modifiable risk factors. The interaction between diet and exercise influences the body fat pattern, which has a significant role in determining insulin sensitivity. Traditional lifestyles, characterized by a diet including less saturated fat and complex carbohydrates, and greater physical activity may protect against the development of cardiovascular risk factors and diabetes, even in the presence of a potential genetic predisposition. In order to address several unanswered questions regarding the feasibility of the prevention of diabetes in the Asian Indian population, a 3-year prospective study in subjects with IGT (the Indian Diabetes Prevention Programme [IDPP-1]), was conducted in Chennai. 37 This was a randomized control study that included 531 subjects with persistent IGT. The four arms of the study were: (i) a control group with no intervention; (ii) the Moderate group, in which sustained lifestyle modification (LSM) was initiated; (iii) a 500 mg day metformin-treated group; and (iv) the LSM + metformin group, treated with 500 mg day metformin in addition to undertaking LSM. In this study, the 3-year cumulative incidence of diabetes was 55%, 39.3%, 40.5%, and 39.5% across the four groups, respectively. The relative risk reduction in the LSM (28.5%), metformin (26.4%), and LSM + metformin (28.2%) groups compared with the control group was very similar. This study showed that progression from IGT to diabetes was very high in Indians. Both LSM and metformin were equally effective and there was no added benefit by combining 24 ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd

8 A. RAMACHANDRAN and C. SNEHALATHA Diabetes in India them. An important outcome of this study was that it showed that the primary prevention of diabetes is possible in the comparatively lean, but highly insulin resistant Asian Indian population by moderate, but consistent, LSM. Both LSM and metformin are costeffective interventions for the prevention of diabetes in India in high-risk subjects. 86 The number of individuals who needed to be treated to prevent a case of diabetes was 6.4 with LSM, 6.9 with metformin, and 6.5 with LSM + metformin. The cost-effectiveness of preventing one case of diabetes was INR (US$1052) for LSM, INR (US$1095) for metformin, and INR ($1359) for LSM + metformin. Conclusions Wide disparities in socioeconomic levels, educational background, and the availability of diabetes care pose major hurdles in the management of this disease in India. The launch of a national program by the Indian Government for prevention and control of diabetes, cardiovascular diseases and stroke (NPCDS) is a major step in strengthening the national capacity for coping with the diabetes epidemic. The most pressing need in India currently is the primary prevention of diabetes. Screening for glucose intolerance as a preventive measure, even in those younger than 30 years of age, is a requisite in Asian Indians because they develop hyperglycemia at a younger age. Disclosure The authors declare that this article has not been, and will not be, submitted for publication in any other journal. The authors also declare that they have no conflict of interest. References 1. Sicree R, Shaw J, Zimmet P. Prevalence and projections. In: Gan D (ed.). Diabetes Atlas International Diabetes Federation, 3rd edn. International Diabetes Federation, Brussels, Belgium, 2006; World Health Organization. World Health Report, Changing History. World Health Organization, Geneva, World Health Organization. Demographic trends. In: Health Situation in the South East Asian Region Regional Office for South East Asia, New Delhi, 2002; Planning Commission of India. Population: A Human and Social Development Available from: planningcommission.nic.in (accessed 20 March 2008). 5. WHO Study Group. Diabetes Mellitus. Technical Report Series no World Health Organization, Geneva, Ahuja MMS. Epidemiological studies on diabetes mellitus in India. In: Ahuja MMS (ed.). Epidemiology of Diabetes in Developing Countries. Interprint, New Delhi, 1979; Tripathy BB, Panda NC, Tej SC, Sahoo GN, Kar BK. Survey for detection of glycosuria, hyperglycaemia and diabetes mellitus in urban and rural areas of Cuttack district. J Assoc Physicians India. 1971; 9: Gupta OP, Joshi MH, Dave SK. Prevalence of diabetes in India. Adv Metab Disord. 1978; 9: Patel JC. Prevalence of hypertension and diabetes mellitus in a rural village. J Diabet Assoc India. 1986; 26: Ramachandran A, Jali MV, Mohan V, Snehalatha C, Viswanathan M. High prevalence of diabetes in an urban population in South India. BMJ. 1988; 297: Verma NP, Mehta SP, Madhu S, Mather HM, Keen H. Prevalence of known diabetes in an urban Indian environment: The Darya Ganj diabetes survey. BMJ. 1986; 293: Rao PV, Ushabala P, Seshiah V, Ahuja MMS, Mather H. The Eluru survey: Prevalence of non-diabetes in a rural Indian population. Diabetes Res Clin Pract. 1989; 7: Ahuja MMS. Recent contributions to the epidemiology of diabetes mellitus in India. Int J Diabetes Dev Ctries. 1991; 11: Ramachandran A, Snehalatha C, Dharmaraj D, Viswanathan M. Prevalence of glucose intolerance in Asian Indians: Urban rural difference and significance of upper body adiposity. Diabetes Care. 1992; 15: Ramachandran A, Snehalatha C, Latha E, Vijay V, Viswanathan M. Rising prevalence of NIDDM in urban population in India. Diabetologia. 1997; 40: Shah SK, Saikia M, Barman NN, Snehalatha C, Ramachandran A. High prevalence of type 2 diabetes in urban population in north-eastern India. Int J Diabetes Dev Ctries. 1998; 18: Asha Bai PV, Krishnaswami CV, Chellamariappan M. Prevalence and incidence of type-2 diabetes and impaired glucose tolerance in a selected Indian urban population. J Assoc Physicians India. 1999; 47: Zargar AH, Khan AK, Masoodi SR et al. Prevalence of type 2 diabetes mellitus and impaired glucose tolerance in the Kashmir Valley of the Indian subcontinent. Diabetes Res Clin Pract. 2000; 47: Kutty VR, Soman CR, Joseph A, Pisharody R, Vijayakumar K. Type 2 diabetes in southern Kerala. Variation in prevalence among geographic divisions within a region. Natl Med J India. 2000; 13: ª 2009 Ruijin Hospital and Blackwell Publishing Asia Pty Ltd 25

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