Associations between weight change and biomarkers of cardiometabolic risk in South Asians: secondary analyses of the PODOSA trial.

BACKGROUND/OBJECTIVES: The association of weight changes with cardiometabolic biomarkers in South Asians has been sparsely studied. SUBJECTS/METHODS: We measured cardiometabolic biomarkers at baseline and after 3 years in the Prevention of Diabetes and Obesity in South Asians Trial. We investigated the effect of a lifestyle intervention on biomarkers in the randomized groups. In addition, treating the population as a single cohort, we estimated the association between change in weight and change in biomarkers. RESULTS: Complete data were available at baseline and after 3 years in 151 participants. At 3 years, there was an adjusted mean reduction of 1·44 kg (95% confidence interval (95% CI): 0.18-2.71) in weight and 1.59 cm (95% CI: 0.08-3.09) in waist circumference in the intervention arm as compared with the control arm. There was no clear evidence of difference between the intervention and control arms in change of mean value of any biomarker. As a single cohort, every 1 kg weight reduction during follow-up was associated with a reduction in triglycerides (-1.3%, P=0.048), alanine aminotransferase (-2.5%, P=0.032), gamma-glutamyl transferase (-2.2%, P=0.040), leptin (-6.5%, P<0.0001), insulin (-3.7%, P=0.0005), fasting glucose (-0.8%, P=0.0071), 2-h glucose (-2.3%, P=0.0002) and Homeostatic Model Assessment of insulin resistance (HOMA-IR: -4.5%, P=0.0002). There was no evidence of associations with other lipid measures, tissue plasminogen activator, markers of inflammation or blood pressure. CONCLUSIONS: We demonstrate that modest weight decrease in SAs is associated with improvements in markers of total and ectopic fat as well as insulin resistance and glycaemia in South Asians at risk of diabetes. Future trials with more intensive weight change are needed to extend these findings.

Culturally adapting the prevention of diabetes and obesity in South Asians (PODOSA) trial.

Type 2 diabetes is extremely common in South Asians, e.g. in men from Pakistani and Indian populations it is about three times as likely as in the general population in England, despite similarities in body mass index. Lifestyle interventions reduce the incidence of diabetes. Trials in Europe and North America have not, however, reported on the impact on South Asian populations separately or provided the details of their cross-cultural adaptation processes. Prevention of diabetes and obesity in South Asians (PODOSA) is a randomized, controlled trial in Scotland of an adapted, lifestyle intervention aimed at reducing weight and increasing physical activity to reduce type 2 diabetes in Indians and Pakistanis. The trial was adapted from the Finnish Diabetes Prevention Study. We describe, reflect on and discuss the following key issues: The core adaptations to the trial design, particularly the delivery of the intervention in homes by dietitians rather than in clinics. The use of both a multilingual panel and professional translators to help translate and/or develop materials. The processes and challenges of phonetic translation. How intervention resources were adapted, modified, newly developed and translated into Urdu and Gurmukhi (written Punjabi). The insights gained in PODOSA (including time pressures on investigators, imperfections in the adaptation process, the power of verbal rather than written information, the utilization of English and the mother-tongue languages simultaneously by participants and the costs) might help the research community, given the challenge of health promotion in multi-ethnic, urban societies.