Impact of lifestyle intervention in primary prevention of Type 2 diabetes did not differ by baseline age and BMI among Asian-Indian people with impaired glucose tolerance.

AIM: To investigate whether the effectiveness of lifestyle interventions on the incidence of diabetes was influenced by the baseline age and BMI of the Asian-Indian participants with prediabetes. METHODS: Pooled data, obtained from two of our Indian Diabetes Prevention Programmes (2006, n=236 and 2013, n=473; total N=709) which had similar baseline characteristics and intervention principles, were analysed. For the present secondary analysis we dichotomously categorized the participants' baseline age (<45 and ≥45 years) and BMI (<25.0 and ≥ 25.0 kg/m2 ). Glycaemic status was ascertained at 6-monthly intervals by oral glucose tolerance tests. The incidence rates of diabetes and relative risk reduction in both the intervention and the control group were calculated for categories of baseline age and BMI. Interactions between the intervention and baseline age and BMI on diabetes risk were also analysed. RESULTS: Incident diabetes was diagnosed in 227 of the total 709 participants (32.0%) [control group 139 participants (38.8%) vs intervention group 88 participants (24.2%)] during the median follow-up period of 2 years. The overall relative risk reduction was 35.4% (95% CI 19.3-48.3). Lifestyle intervention was equally effective in both age groups [relative risk reduction in those aged <45 years: 43.7% (95% CI 19.8-60.5) and in those aged ≥ 45 years: 28.9% (95% CI 5.3-46.6) P for interaction = 0.52] and in categories of BMI [BMI <25 kg/m2 : 36.1% (95% CI 9.5-54.9); and BMI ≥ 25 kg/m2 : 34.8% (95% CI 12.9-51.2); P for interaction = 0.95]. CONCLUSIONS: In Asian-Indian individuals with prediabetes, the effectiveness of lifestyle intervention was not modified by baseline age and BMI.

Hypertriglyceridaemic waist phenotype as a simple predictive marker of incident diabetes in Asian-Indian men with prediabetes.

AIM: To determine prospectively the association of baseline hypertriglyceridaemic waist phenotype with incident diabetes in Asian-Indian men with impaired glucose tolerance. METHODS: In a randomized 2-year diabetes prevention trial in 517 men with impaired glucose tolerance, 123 (23.8%) developed diabetes. Baseline anthropometric, metabolic and clinical variables were estimated. Associations of hypertriglyceridaemic waist phenotype (waist circumference ≥ 90cm and a serum triglyceride level of ≥ 1.7 mmol/l) with insulin resistance and incident diabetes were assessed using multiple linear regression and Cox's proportional hazard models, respectively. RESULTS: Men with an isolated enlarged waistline and hypertriglyceridaemic waist phenotype had significantly higher BMI and percentage of total body fat compared with the group with normal waistline and triglyceride levels and the group with isolated hypertriglyceridaemia. The men with hypertriglyceridaemic waist phenotype had higher insulin resistance (mean ± sd homeostasis model assessment of insulin resistance value: 3.6 ± 1.5) compared with those in the isolated enlarged waistline, the isolated hypertriglyceridaemia or the normal waistline and triglyceride level groups (3.1 ± 1.4, 2.7 ± 1.0 and 2.5 ± 1.1, respectively, all P < 0.05 compared with hypertriglyceridaemic waist phenotype). Multiple linear regression analyses showed that hypertriglyceridaemic waist phenotype was significantly associated with insulin resistance after adjusting for age, BMI, family history, percentage of total body fat, smoking, alcohol intake, 2-h plasma glucose and HDL cholesterol level. Hypertriglyceridaemic waist phenotype was independently associated with incident diabetes after adjusting for the above confounders and gamma-glutamyl transferase (hazard ratio 1.49, 95% CI 1.01-2.21; P = 0.047). The association of hypertriglyceridaemic waist phenotype with incident diabetes was abolished when insulin resistance was introduced into the model (hazard ratio 1.39, 95% CI 0.092-2.10; P=0.12). CONCLUSIONS: Hypertriglyceridaemic waist phenotype is a simple clinical proxy measurement for insulin resistance and is strongly associated with incident diabetes in Asian-Indian men with impaired glucose tolerance.

Primary prevention of Type 2 diabetes in South Asians--challenges and the way forward.

Preventing diabetes is of enormous value, particularly for the South Asian countries, which have a huge healthcare burden from the onslaught of the disease. Type 2 diabetes has been proved to be preventable using lifestyle changes, even in South Asians despite their heightened risk profile. Strategies to improve awareness about diabetes and translation of preventive measures by innovative, culturally specific programmes have to be implemented at national levels. Integrated involvement of the government, community, media, healthcare and education services, and financial support from national and international organizations, are required. South Asian countries have initiated national programmes for diabetes prevention and management. It is also encouraging to note that joint ventures between developed countries such as the USA, UK and other European countries and centres of excellence in South Asia have been initiated to develop large-scale, community-oriented, pragmatic intervention strategies.

Predictive value of HbA1c for incident diabetes among subjects with impaired glucose tolerance--analysis of the Indian Diabetes Prevention Programmes.

AIMS: The objectives of the study were to assess the predictive value of baseline HbA(1c) for incident diabetes among the participants with impaired glucose tolerance in the Indian Diabetes Prevention Programmes 1 and 2. METHODS: Data at baseline and at 3-year follow-up were analysed in combined cohorts of the Indian Diabetes Prevention Programmes 1 and 2. Within the 3 years, 324 of the 845 participants developed diabetes (World Health Organization criteria). The predictive value of baseline HbA(1c) for incident diabetes was determined by logistic regression analysis. RESULTS: Baseline HbA(1c) values had heterogenous distribution. The distribution was similar in isolated impaired glucose tolerance or in impaired glucose tolerance in combination with impaired fasting glucose. A progressive increase in diabetes occurred with increasing HbA(1c). HbA(1c) showed the strongest association with incident diabetes in the multiple logistic regression analysis (odds ratio 3.548, P < 0.0001). The cut-off HbA(1c) of 43 mmol/mol (6.05%) had 67% sensitivity and 60% specificity to predict future diabetes. The diagnostic sensitivity of HbA(1c) of ≥ 48 mmol/mol (≥ 6.5%) was only 51%, with a specificity of 87%, when compared with the oral glucose tolerance glucose values. CONCLUSIONS: Baseline HbA(1c) was highly predictive of future diabetes in Asian Indian subjects with impaired glucose tolerance and nearly 60% of the incidence occurred with values ≥ 42 mmol/mol (≥ 6.0). Diagnostic sensitivity of HbA(1c) ≥ 48 mmol/mol (≥ 6.5%) for new diabetes was only 51% using the oral glucose tolerance test as the standard for comparison.