Indians Diabetes Prevention Program Research Articles

Analysis of an Indian diabetes prevention programme on association of adipokines and a hepatokine with incident diabetes

To study the association and possible predictive role of visfatin, resistin, fetuin-A and chemerin with incident type 2 diabetes (T2DM) among Asian Indians with prediabetes. Their association with insulin resistance, β-cell function, glycaemia and anthropometry were also studied. This is a nested case–control study of a large 2-year prospective prevention trial in persons at high risk of developing T2DM. Baseline HbA1c values between 6.0% (42 mmol/mol) and 6.2% (44 mmol/mol) were chosen for this analysis (n = 144). At follow-up, persons with incident T2DM (HbA1c ≥ 6.5%, 48 mmol/mol) were grouped as cases (n = 72) and those reverted to normoglycaemia, (HbA1c < 5.7% (39 mmol/mol) as controls (n = 72). Insulin resistance showed the strongest association with incident T2DM ((Odds Ratio (OR): 23.22 [95%CI 6.36–84.77]; p < 0.0001). Baseline visfatin (OR: 6.56 [95%CI 2.21–19.5]; p < 0.001) and fetuin-A (OR: 1.01 [95%CI (1.01–1.04)]; p < 0.0001) independently contributed to the conversion of prediabetes to T2DM. The contribution was significantly higher when their elevated levels coexisted (OR: 12.63 [95%CI 3.57–44.63]; p < 0.0001). The area under the curve was 0.77 ± SE 0.4 (95%CI 0.69–0.85) and 0.80 ± SE 0.04 (95%CI 0.73–0.88) for visfatin (median 17.7 ng/ml, sensitivity and specificity: 75%, p < 0.0001) and fetuin-A (mean 236.2 µg/ml, sensitivity: 71%, specificity: 75%, p < 0.0001) respectively. Higher baseline visfatin and fetuin-A concentrations are strongly associated with incident T2DM and are predictive of future diabetes.

1588-P: Regression to Normal Glucose Regulation in American Indians and Alaska Natives of a Diabetes Prevention Program

Objectives: To evaluate whether regression from impaired glucose regulation (IGR) to normal glucose regulation (NGR) after one year of a lifestyle intervention reduces diabetes risk in American Indians and Alaska Natives (AI/ANs). Additionally, we sought to identify predictors for regression to NGR and understand possible mechanisms for the association between NGR and future diabetes risk. Research Design and Methods: Data from participants enrolled from 2006 to 2009 in the Special Diabetes Program for Indians Diabetes Prevention Program with IGR at baseline and an oral glucose tolerance test (OGTT) at year 1 were analyzed (N = 1443). Based on OGTT results, participants were classified into four categories: NGR; isolated IFG (iIFG); isolated IGT (iIGT); or both IFG and IGT (IFG/IGT). Cox regression models were used to estimate the subsequent diabetes risk (year 1 to year 3) by year 1 glucose status. Mediation analysis was employed to estimate the proportions of the association between year 1 glycemic status and diabetes risk explained by specific factors. Results: Those who reverted to NGR at year 1 (38%) had lower diabetes risk than those with sustained IGR (adjusted hazard ratio (HR) = 0.28, 95% CI: 0.12-0.67). Compared to the NGR group at year 1, IFG/IGT carried the highest risk of developing diabetes with an adjusted HR of 4.72 (95% CI: 1.84-12.07), followed by the iIGT group (HR=3.26, 95% CI: 0.96-11.12; p-value=0.059) and the iIFG group (HR=3.13, 95% CI: 1.27-7.31). The lower risk associated with regression to NGR was explained by both baseline risk factors and differences in weight loss. Metformin use, weight loss, and increase in exercise were modifiable risk factors associated with a higher odds of regression to NGR. Conclusions: AI/AN patients with prediabetes who reverted to NGR had a reduced risk of developing type 2 diabetes over the next two years; modifiable risk factors explained a major proportion of risk reduction associated with NGR. Disclosure K.A. Pratte: None. A. Johnson: None. J. Beals: None. A. Bullock: None. S.M. Manson: None. L. Jiang: None. Funding Indian Health Service (HHSI242200400049C to S.M.M.); National Institute of Diabetes and Digestive and Kidney Diseases (1P30DK092923 to S.M.M), (R21DK108187 to L.J.)

Neighborhood characteristics and lifestyle intervention outcomes: Results from the Special Diabetes Program for Indians

Growing evidence reveals various neighborhood conditions are associated with the risk of developing type 2 diabetes. It is unknown, however, whether the effectiveness of diabetes prevention interventions is also influenced by neighborhood characteristics. The purpose of the current study is to examine the impact of neighborhood characteristics on the outcomes of a lifestyle intervention to prevent diabetes in American Indians and Alaska Natives (AI/ANs). Year 2000 US Census Tract data were linked with those from the Special Diabetes Program for Indians Diabetes Prevention Program (SDPI-DP), an evidence-based lifestyle intervention implemented in 36 AI/AN grantee sites across the US. A total of 3394 participants started the intervention between 01/01/2006 and 07/31/2009 and were followed by 07/31/2016. In 2016–2017, data analyses were conducted to evaluate the relationships of neighborhood characteristics with intervention outcomes, controlling for individual level socioeconomic status. AI/ANs from sites located in neighborhoods with higher median household income had 38% lower risk of developing diabetes than those from sites with lower neighborhood income (adjusted hazard ratio = 0.65, 95% CI: 0.47–0.90). Further, those from sites with higher neighborhood concentrations of AI/ANs achieved less BMI reduction and physical activity increase. Meanwhile, participants from sites with higher neighborhood level of vehicle occupancy made more improvement in BMI and diet. Lifestyle intervention effectiveness was not optimal when the intervention was implemented at sites with disadvantaged neighborhood characteristics. Meaningful improvements in socioeconomic and other neighborhood disadvantages of vulnerable populations could be important in stemming the global epidemic of diabetes.

Derivation and Evaluation of a Risk-Scoring Tool to Predict Participant Attrition in a Lifestyle Intervention Project.

Participant attrition in clinical trials and community-based interventions is a serious, common, and costly problem. In order to develop a simple predictive scoring system that can quantify the risk of participant attrition in a lifestyle intervention project, we analyzed data from the Special Diabetes Program for Indians Diabetes Prevention Program (SDPI-DP), an evidence-based lifestyle intervention to prevent diabetes in 36 American Indian and Alaska Native communities. SDPI-DP participants were randomly divided into a derivation cohort (n = 1600) and a validation cohort (n = 801). Logistic regressions were used to develop a scoring system from the derivation cohort. The discriminatory power and calibration properties of the system were assessed using the validation cohort. Seven independent factors predicted program attrition: gender, age, household income, comorbidity, chronic pain, site's user population size, and average age of site staff. Six factors predicted long-term attrition: gender, age, marital status, chronic pain, site's user population size, and average age of site staff. Each model exhibited moderate to fair discriminatory power (C statistic in the validation set: 0.70 for program attrition, and 0.66 for long-term attrition) and excellent calibration. The resulting scoring system offers a low-technology approach to identify participants at elevated risk for attrition in future similar behavioral modification intervention projects, which may inform appropriate allocation of retention resources. This approach also serves as a model for other efforts to prevent participant attrition.

Socioeconomic Disparities in Weight and Behavioral Outcomes Among American Indian and Alaska Native Participants of a Translational Lifestyle Intervention Project.

OBJECTIVETo investigate possible socioeconomic disparities in weight and behavioral outcomes among American Indian and Alaska Native (AI/AN) participants in a translational diabetes prevention project.RESEARCH DESIGN AND METHODSWe analyzed data from the Special Diabetes Program for Indians Diabetes Prevention (SDPI-DP) Program, an evidence-based lifestyle intervention to prevent diabetes in 36 AI/AN grantee sites. A total of 2,553 participants started the 16-session Lifestyle Balance Curriculum between 1 January 2006 and 31 July 2008. Linear mixed models were used to evaluate the relationships of participant and staff socioeconomic characteristics with weight and behavioral outcomes at the end of the curriculum.RESULTSA strong, graded association existed between lower household income and less BMI reduction, which remained significant after adjusting for other socioeconomic characteristics. Compared with others, participants with annual income <$15,000 also had less improvement in physical activity and unhealthy food consumption in bivariate models, but the relationships were only marginally significant in multivariate regressions. Furthermore, grantee sites with fewer professionally prepared staff were less successful at improving participant BMI and healthy food consumption than the other sites. The strong association between income and BMI reduction was reduced by 20–30% in the models with changes in diet variables but was unrelated to changes in physical activity.CONCLUSIONSSignificant socioeconomic disparities exist in weight outcomes of lifestyle intervention at both participant and site staff levels. Helping low-income participants choose more affordable healthy foods and increasing the proportion of professionally trained staff might be practical ways to maximize the effectiveness of lifestyle interventions implemented in “real-world” settings.

Longitudinal Patterns of Stages of Change for Exercise and Lifestyle Intervention Outcomes: An Application of Latent Class Analysis with Distal Outcomes.

Stages of change measure an individual's readiness to alter a health behavior. This study examined the latent longitudinal patterns of stages of change (SoC) for regular exercise over time among individuals participating in a lifestyle intervention project. It also investigated the association between the longitudinal patterns of SoC and intervention outcomes using a new statistical method to assess the relationship between latent class membership and distal outcomes. We analyzed data from the Special Diabetes Program for Indians Diabetes Prevention Program, a lifestyle intervention program to prevent diabetes among American Indians and Alaska Natives. Latent class analysis (LCA) was conducted to identify the longitudinal patterns of SoC for regular exercise reported at three time points. LCA with distal outcomes was performed to investigate the associations between latent class membership and behavioral changes after the intervention. The parameters and standard errors of the LCA with distal outcomes models were estimated using an improved three-step approach. Three latent classes were identified: Pre-action, Transition, and Maintenance classes. The Transition class, where stage progression occurred, had the greatest improvements in physical activity and weight outcomes at both time points post-baseline among female participants. It also had the largest improvements in weight outcomes among male participants. Furthermore, the Pre-action class had more attenuation in the improvements they had achieved initially than the other two classes. These findings suggest the potential importance of motivating participants to modify their readiness for behavioral change in future lifestyle interventions.

Participant and Site Characteristics Related to Participant Retention in a Diabetes Prevention Translational Project

Using multilevel analysis, this study investigated participant and site characteristics associated with participant retention in a multisite diabetes prevention translational project among American Indian and Alaska Native (AI/AN) people. We analyzed data from the Special Diabetes Program for Indians Diabetes Prevention Program (SDPI-DP), a lifestyle intervention to prevent diabetes implemented in 36 AI/AN grantee sites. A total of 2,553 participants were recruited and started the intervention between January 1, 2006 and July 31, 2008. They were offered the 16-session Lifestyle Balance Curriculum from the Diabetes Prevention Program (DPP) in the first 16-24 weeks of intervention. Generalized estimating equation models and proportional hazards models with robust standard error estimates were used to evaluate the relationships of participant and site characteristics with retention. As of July 31, 2009, about 50 % of SDPI-DP participants were lost to follow-up. Those who were younger, male, with lower household income, no family support person, and more baseline chronic pain were at higher risk for both short-term and long-term retention failure (i.e., not completing all 16 DPP sessions and loss to follow-up, respectively). Sites with large user populations and younger staff had lower likelihood of retaining participants successfully. Other site characteristics related to higher risk for retention failure included staff rating of participant disinterest in SDPI-DP and barriers to participant transportation and child/elder care. Future translational initiatives need to pay attention to both participant- and site-level factors in order to maximize participant retention.

Reducing the Risk of Developing Diabetes

Reducing the Risk of Developing Diabetes

Latent Class Analysis of Stages of Change for Multiple Health Behaviors: Results from the Special Diabetes Program for Indians Diabetes Prevention Program

This study sought to identify latent subgroups among American Indian and Alaska Native (AI/AN) patients with pre-diabetes based on their stages of change for multiple health behaviors. We analyzed baseline data from participants of the Special Diabetes Program for Indians Diabetes Prevention (SDPI-DP) Program, a lifestyle intervention program to prevent diabetes among AI/ANs. A total of 3,135 participants completed baseline questionnaires assessing stages of change for multiple health behaviors, specifically exercise, healthy eating, and weight loss. Latent class analysis was used to identify subgroups of people based on their answers to stages of change questions. Covariates were added to the latent class analyses to investigate how class membership was related to sociodemographic, behavioral, and psychosocial factors. Three classes were identified based on the distributions of the stages of change variables: Contemplation, Preparation, and Action/Maintenance classes. Male and retired participants were more likely to be in more advanced stages. Those who exercised more, ate healthier diets, and weighed less were significantly more likely to be in the Action/Maintenance class. Further, the participants who had higher self-efficacy, stronger family support, and better health-related quality of life had higher odds of being in the Action/Maintenance class. In conclusion, we found that stages of change for multiple behaviors can be summarized by a three-class model in this sample. Investigating the relationships between latent classes and intervention outcomes represents important next steps to extend the findings of the current study.

Traditions and Diabetes Prevention: A Healthy Path for Native Americans

My work in the area of diabetes prevention began in 2006, as an instructor and lifestyle coach for the Special Diabetes Program for Indians (SDPI) Diabetes Prevention Program, with funding awarded to the Winnebago Tribe of Nebraska. Diabetes is serious. Diabetes is deadly. To see the devastating impact it can have on a population, sadly, one need look no further than to the first nation of people to inhabit North America. Recent data from the Centers for Disease Control and Prevention (CDC) and Indian Health Service (IHS) show that in some American Indian and Alaska Native communities, diabetes prevalence among adults is as high as 60%.1 One in six American Indian and Alaska Native adults has diagnosed diabetes—more than double the prevalence rate for the general U.S. population.1 But it wasn't always this way. Consider this: Less than 100 years ago, diabetes was virtually unknown in native communities. It was not until after World War II that diabetes cases began to be reported by IHS providers. In fact, a century ago, all chronic diseases, including diabetes, were practically nonexistent in Indian country. As recently as 1955, diabetes was unrecognized as a leading cause of death as evidenced by its absence in a listing of the 10 most frequent causes of death for this population. However, by 2009, diabetes had jumped to number four on the list. American Indians and Alaska Natives now have the highest diabetes prevalence rates of all racial and ethnic groups in the United States. More than 16% of the members of this population have been diagnosed, compared to 8.7% of non-Hispanic whites. The Pima Indians of Arizona have the highest rates of diabetes in the world, with more than 50% having a diagnosis of type 2 diabetes. Data from the 2003–2004 National Health Interview …

Voglibose for prevention of type 2 diabetes mellitus

Lifestyle interventions are effective for the prevention of type 2 diabetes in different populations with impaired glucose tolerance in the USA, north Europe, China, and Japan. Not only were the results impressive at the end of the intensive intervention trials, but long-term follow-up studies also confirmed the effect of lifestyle interventions for the prevention of diabetes in individuals at high risk of developing the disease. Various drugs are efficacious in the prevention of type 2 diabetes in individuals with impaired glucose tolerance (figure). Glucose-lowering drugs preventedthe development of type 2 diabetes in placebo-controlled clinical trials. Metformin reduced the relative risk of new-onset diabetes at the end of the US Diabetes Prevention Programme by 31%, and a 26% reduction was seen inthe Indian Diabetes Prevention Programme. Treatment with thiazolidinediones resulted in a greater risk reduction (60% with rosiglitazone in DREAM, and 81% with pioglitazone in ACT-NOW). However, because both metformin and glitazones positively affect the pathophysiology of type 2 diabetes, and because the main reported results were analysed without any washout period, the distinction between a masking and atrue preventive effect is almost impossible.

Beneficial effects of strategies for primary prevention of diabetes on cardiovascular risk factors: results of the Indian Diabetes Prevention Programme

In subjects with impaired glucose tolerance (IGT) who participated in the Indian Diabetes Prevention Programme (IDPP), abnormalities related to body mass index, waist circumference (WC), blood pressure (BP), lipid profile and electrocardiography were analysed (at baseline and third-year follow-up) in control, lifestyle modification (LSM), metformin (MET) and LSM + MET groups. At baseline, elevated levels of low-density lipoprotein cholesterol (LDL-C) showed the highest (78.6%) and total cholesterol (TC) showed the lowest (42%) prevalence. At follow-up, prevalence of hypertension (BP > or = 130/> or = 85 mmHg) had increased significantly in all groups. Cardiovascular abnormalities were lower in intervention groups, with the lowest rates in the MET group (p=0.013 vs. control); the LDL-C level decreased in intervention groups. In this programme, Asian Indian IGT subjects were observed to have a high prevalence of cardiovascular risk factors. LSM and MET had beneficial effects on the atherogenic phenotype of lipids but had no influence on blood pressure.

Cost-Effectiveness of the Interventions in the Primary Prevention of Diabetes Among Asian Indians

In the Indian Diabetes Prevention Programme (IDPP), a 3-year randomized, controlled trial, lifestyle modification (LSM) and metformin helped to prevent type 2 diabetes in subjects with impaired glucose tolerance (IGT). The direct medical costs and cost-effectiveness of the interventions relative to the control group are reported here. Relative effectiveness and costs of interventions (LSM, metformin, and LSM and metformin) in the IDPP were estimated from the health care system perspective. Costs of intervention considered were only the direct medical costs. Direct nonmedical, indirect, and research costs were excluded. The cost-effectiveness of interventions was measured as the amount spent to prevent one case of diabetes within the 3-year trial period. The direct medical cost to identify one subject with IGT was Indian rupees (INR) 5,278 ($117). Direct medical costs of interventions over the 3-year trial period were INR 2,739 ($61) per subject in the control group, INR 10,136 ($225) with LSM, INR 9,881 ($220) with metformin, and INR 12,144 ($270) with LSM and metformin. The number of individuals needed to treat to prevent a case of diabetes was 6.4 with LSM, 6.9 with metformin, and 6.5 with LSM and metformin. Cost-effectiveness to prevent one case of diabetes with LSM was INR 47,341 ($1,052), with metformin INR 49,280 ($1,095), and with LSM and metformin INR 61,133 ($1,359). Both LSM and metformin were cost-effective interventions for preventing diabetes among high risk-individuals in India and perhaps may be useful in other developing countries as well. The long-term cost-effectiveness of the interventions needs to be assessed.

Glucose lowering and diabetes prevention: are they the same?

The prevention of type 2 diabetes is a major public-health issue. The results of the Diabetes REduction Assessment with ramipril and rosiglitazone Medication (DREAM) trial, 1 DREAM trial investigatorsEffect of rosiglitazone on the frequency of diabetes in patients with impaired glucose tolerance or impaired fasting glucose: a randomised controlled trial. Lancet. 2006; published online Sept 15. DOI:10.1016/S0140-6736(06)69420-8 Google Scholar show that progression to diabetes in people with impaired glucose regulation can be diminished. The relative risk reduction of rosiglitazone seen in DREAM was similar to that obtained by lifestyle interventions 2 Tuomilehto J Lindström J Eriksson JG et al. Prevention of type 2 diabetes mellitus by changes in lifestyle among subjects with impaired glucose tolerance. N Engl J Med. 2001; 344: 1343-1350 Crossref PubMed Scopus (8312) Google Scholar , 3 The Diabetes Prevention Program Research GroupReduction in the incidence of type 2 diabetes with lifestyle intervention or metformin. N Engl J Med. 2002; 346: 393-403 Crossref PubMed Scopus (14420) Google Scholar , 4 Ramachandran A Snehalatha C Mary S Mukesh B Bhaskar AD Vijay V The Indian Diabetes Prevention Programme shows that lifestyle modification and metformin prevent type 2 diabetes in Asian Indian subjects with impaired glucose tolerance (IDPP-1). Diabetologia. 2006; 49: 289-297 Crossref PubMed Scopus (1316) Google Scholar , 5 Eriksson KF Lindgärde F Prevention of type 2 (non-insulin-dependent) diabetes mellitus by diet and physical exercise. The 6-year Malmo feasibility study. Diabetologia. 1991; 34: 891-898 Crossref PubMed Scopus (1015) Google Scholar and much the same as that seen in two previous trials of the now withdrawn thiazolidinedione troglitazone. 6 Buchanan TA Xiang AH Peters RK et al. Preservation of pancreatic beta-cell function and prevention of type 2 diabetes by pharmacological treatment of insulin resistance in high-risk hispanic women. Diabetes. 2002; 51: 2796-2803 Crossref PubMed Scopus (1204) Google Scholar , 7 The Diabetes Prevention Program Research GroupPrevention of type 2 diabetes with troglitazone in the Diabetes Prevention Program. Diabetes. 2005; 54: 1150-1156 Crossref PubMed Scopus (402) Google Scholar Effect of rosiglitazone on the frequency of diabetes in patients with impaired glucose tolerance or impaired fasting glucose: a randomised controlled trialRosiglitazone at 8 mg daily for 3 years substantially reduces incident type 2 diabetes and increases the likelihood of regression to normoglycaemia in adults with impaired fasting glucose or impaired glucose tolerance, or both. Full-Text PDF Open Access

Metabolic syndrome does not increase the risk of conversion of impaired glucose tolerance to diabetes in Asian Indians—Result of Indian diabetes prevention programme

Aims In this study, we assessed for the prevalence of metabolic syndrome (MetS) in the cohort of subjects with impaired glucose tolerance (IGT) in the Indian Diabetes Prevention Programme and studied whether the syndrome enhanced the conversion to diabetes. Methods Effectiveness of lifestyle modification (LSM), metformin (Met) and LSM plus Met was tested in a randomised, controlled primary prevention study in subjects with IGT n = 502 (M:W 397:105) at a median follow up of 30 months. Baseline prevalence of MetS was calculated using the WHO criteria. Insulin resistance (IR) was calculated using homeostasis model assessment (HOMA) method. Results MetS was present in 233 subjects (46.4%; 95% CI 41.9–50.9) in the total group, in men ( n = 168; 42.3%; 95% CI 37.4–47.3) and in women ( n = 65; 61.9%; 95% CI 51.9–71.2) (men versus women χ 2 = 12.8, p = 0.0005). Insulin resistance (HOMA-IR ≥ 4.1) was present in 69.1% with no gender difference. IR increased proportionately with increasing number of abnormalities, in IGT (39.8%), IGT plus one abnormality (56.5%) and IGT plus any two or more abnormalities (69.1%) (Mantel Haenszel χ 2 = 22.8, p < 0.0001). Incidence of diabetes was similar in subjects with (40.3%) ( n = 94/233) or without (40.1%) ( n = 108/269) MetS ( p = 0.97). Cox's regression analysis confirmed that MetS did not enhance the conversion rate of IGT to diabetes both in the control (HR = 0.88, 95% CI 0.53–1.47, p = 0.63) and in the total group (HR = 1.02, 95% CI 0.78–1.35, p = 0.88), after correcting for effects of intervention. Conclusion Prevalence of MetS is high in Asian Indian IGT subjects, especially in women. However, it did not influence the rate of conversion of IGT to diabetes.

Persistent impaired glucose tolerance has similar rate of risk factors as for diabetes—Results of Indian Diabetes Prevention Programme (IDPP)

Objective To determine the occurrence of persistent impaired glucose tolerance (IGT) (two times OGTT positive) and to compare the physical and clinical characteristics with subjects having transient IGT or diabetes. Research design and methods Nondiabetic subjects aged 35–55 years were screened ( n = 10,839, M:W 8667:2172) using 2 h capillary blood glucose. IGT was diagnosed in 1332 (12.3%). Among them, 1025 (77%) responded for a second OGTT and 531 subjects (51.8%) had persistent IGT. Biochemical, demographic and anthropometric characteristics were compared among the normal (NGT, 30.1%), IGT and diabetic subjects (DM, 18%) at second GTT. Results All had similar age. BMI, waist circumference and body fat percentage were lower in NGT than in IGT and diabetes. IGT and diabetes had similar characteristics. Family history of diabetes was the highest in persistent IGT. Conclusion Among the screened subjects, 1 in 20 had persistent IGT. Subject with persistent IGT had higher rates of risk factors for diabetes, such as high BMI, waist circumference and body fat percentage.

The Indian Diabetes Prevention Programme shows that lifestyle modification and metformin prevent type 2 diabetes in Asian Indian subjects with impaired glucose tolerance (IDPP-1)

Lifestyle modification helps in the primary prevention of diabetes in multiethnic American, Finnish and Chinese populations. In a prospective community-based study, we tested whether the progression to diabetes could be influenced by interventions in native Asian Indians with IGT who were younger, leaner and more insulin resistant than the above populations. We randomised 531 (421 men 110 women) subjects with IGT (mean age 45.9+/-5.7 years, BMI 25.8+/-3.5 kg/m(2)) into four groups. Group 1 was the control, Group 2 was given advice on lifestyle modification (LSM), Group 3 was treated with metformin (MET) and Group 4 was given LSM plus MET. The primary outcome measure was type 2 diabetes as diagnosed using World Health Organization criteria. The median follow-up period was 30 months, and the 3-year cumulative incidences of diabetes were 55.0%, 39.3%, 40.5% and 39.5% in Groups 1-4, respectively. The relative risk reduction was 28.5% with LSM (95% CI 20.5-37.3, p=0.018), 26.4% with MET (95% CI 19.1-35.1, p=0.029) and 28.2% with LSM + MET (95% CI 20.3-37.0, p=0.022), as compared with the control group. The number needed to treat to prevent one incident case of diabetes was 6.4 for LSM, 6.9 for MET and 6.5 for LSM + MET. Progression of IGT to diabetes is high in native Asian Indians. Both LSM and MET significantly reduced the incidence of diabetes in Asian Indians with IGT; there was no added benefit from combining them.