Short CommunicationDid the weight loss in the Prevention of Diabetes and Obesity in South Asians (PODOSA) trial differ by sex? An exploratory analysis
Introduction
Little is known on whether weight loss interventions in prediabetic people affect males and females differently as the trials were not designed to test sex differences in adherence or response to intervention. The US Diabetes Prevention Programme found greater weight loss in men than women but the difference was not stated.1 A systematic review and meta-analysis on sex-specific differences in diabetes prevention found no evidence of sex differences in weight loss in people with prediabetes although weight loss at 3-years follow-up was greater in men than women (confidence intervals [CI] overlapped).2 In a further systematic review of weight loss interventions, weight loss was found to be greater in men than in women in 80% of studies where a direct comparison was possible. However in these reports, there was a lack of data on whether sex differences with weight loss interventions were evident in individuals of South Asian ethnicity.3 This is of importance given the high risk of diabetes in South Asians and evidence that weight loss interventions may be somewhat less effective in South Asians than other ethnic groups.4, 5, 6
A secondary analysis of the BEACHeS feasibility study in Pakistani and Bangladeshi-origin children suggested sex differences in response to the intervention in South Asian population and emphasises the need of examining sex differences in future; it showed the intervention reduced adiposity in girls but not boys, with girls in the intervention group gaining less weight, body mass index (BMI), waist circumference central and thigh skinfold than their respective controls (P < 0.05).7 In Scotland, the Prevention of Diabetes and Obesity in South Asians (PODOSA) trial aimed at reducing the risk of developing type 2 diabetes in people from South Asian descent by encouraging weight loss through culturally adapted diet intervention and increase of physical activity.4, 8
There is a need to study sex differences in the effect of weight loss interventions specifically in prediabetic South Asian populations. Consequently, as an exploratory post hoc analysis, we aimed to assess whether men or women were more likely to lose weight in the PODOSA trial.
Section snippets
The PODOSA trial: study design, participants, randomisation and intervention
he details of the PODOSA trial have been published.4, 8 The trial recruited individuals at high risk of developing type 2 diabetes through screening using an oral glucose tolerance test. Eligibility for recruitment was being of Indian or Pakistani origin, aged 35 years and over, a waist circumference of 90 cm and over for men and 80 cm and over for women, no diagnosis of diabetes and a cooperative family cook. Randomisation was done at the family level, stratified by location (Edinburgh or
Results
Table 1 part A shows that for men, the mean change in weight in the intervention and control groups combined was −1.17 kg (SD 3.69). On average, we observed a moderate weight loss in the intervention group (mean −2.23 kg; SD 3.79) and a trivial weight loss in the control group (mean −0.06 kg; SD 3.27). For women, the mean change in weight in both groups combined was 0.40 kg (SD 4.07) with a slight weight loss in the intervention group (mean −0.18 kg; SD 4.20) but a weight gain in the control
Discussion
This additional exploratory analysis on the South Asian participants of the PODOSA trial showed evidence of sex differences with men losing more weight on average than women. We found an effect of the intervention on change in weight as previously reported in the main analysis.4 However, looking at the interaction between sex and randomisation group, the differential effect of the intervention between men and women compared with control was not statistically significant though this could be a
Acknowledgements
The authors have previously thanked many individuals who contributed to the trial.4, 8 We further acknowledge Professor Gordon Murray for his guidance on analysis. We thank Professors Michael J E Lean, Sarah Wild and Naveed Sattar for their inputs to the PODOSA trial.
Ethical approval
Ethical approval was obtained from the Scotland A Research Ethics Committee (07-MRE10-2) and participants gave written, informed consent before screening. This trial is registered, number ISRCTN25729565.
Funding
This work was funded by the
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Cited by (1)
Sex and gender differences in prevention of type 2 diabetes
2018, Frontiers in Endocrinology