Feasibility and effectiveness of a targeted diabetes prevention program for 18 to 60-year-old South Asian migrants: design and methods of the DH!AAN study

Abstract

BackgroundSouth Asian migrants are at particularly high risk of type 2 diabetes. Previous studies have shown that intensive lifestyle interventions may prevent the onset of diabetes. Such interventions have not been culturally adapted and evaluated among South Asians in industrialized countries. Therefore, we have set up a randomized controlled trial to study the effectiveness of a targeted lifestyle intervention for the risk of type 2 diabetes and cardiovascular risk factors among 18 to 60-year-old Hindustani Surinamese (South Asians) in The Hague, the Netherlands. Here we present the study design and describe the characteristics of those recruited.MethodsBetween May 18, 2009 and October 11, 2010, we screened 2307 Hindustani Surinamese (18–60 years old) living in The Hague. We sent invitations to participate to those who had an impaired fasting glucose of 5.6-6.9 mmol/l, an impaired glucose tolerance of 7.8-11.0 mmol/L, a glycated hemoglobin level of 6.0% or more and/or a value of 2.39 or more for the homeostasis model assessment of estimated insulin resistance. In total, 536 people (56.1% of those eligible) participated. People with a higher level of education and a family history of type 2 diabetes were more likely to participate. The control and intervention groups were similar with regard to important background characteristics. The intervention group will receive a culturally targeted intervention consisting of dietary counseling using motivational interviewing and a supervised physical activity program. The control group will receive generic lifestyle advice. To determine the effectiveness, a physical examination (anthropometrics, cardiorespiratory test, lipid profile, and measures of oral glucose tolerance, glycated hemoglobin, and insulin) and interview (physical activity, diet, quality of life, and intermediate outcomes) were carried out at baseline and will be repeated at 1 year and 2 years. The process and the costs will be evaluated.DiscussionThis trial will provide insight into the feasibility and effectiveness of a targeted, intensive, lifestyle intervention for the risk of type 2 diabetes and cardiovascular risk factors among 18 to 60-year-old South Asians.Trial registrationDutch Trial Register: NTR1499

Intensive Lifestyle Intervention in General Practice to Prevent Type 2 Diabetes among 18 to 60-Year-Old South Asians: 1-Year Effects on the Weight Status and Metabolic Profile of Participants in a Randomized Controlled Trial

“…The detailed methods of this study and the process of adapting the lifestyle intervention for the socio-cultural and socio-cognitive determinants of Hindustani Surinamese have been described earlier [19], [20]. In brief, 2307 Hindustani Surinamese (18–60 years old) living in The Hague, Netherlands, were screened via general practices between 18 May 2009 and 11 October 2010.…”

“…We invited the screening participants to participate in the trial if they had an impaired fasting glucose (5.7–6.9 mmol/l), an impaired glucose tolerance (2-h post-load glucose of 7.8–10.9 mmol/l), a glycated haemoglobin level of 42–46 mmol/mol, and/or a value of 2.39 or more for the homeostasis model assessment of estimated insulin resistance (HOMA-IR) [19] We excluded anyone who was already involved in a lifestyle programme, was pregnant, was known to have type 2 diabetes or a chronic disease that made participation in the intervention impossible, and/or used drugs interfering with plasma glucose levels. Furthermore, we excluded participants with newly diagnosed type 2 diabetes (i.e.…”

“…a fasting glucose ≥7.0 mmol/l, a 2-h post-load glucose ≥11.0 mmol/l, or a haemoglobin (Hb)-A1c level ≥48 mmol/mol) and referred them to regular clinical care. We used a computer-generated randomisation list (individual one-to-one randomisation) to randomly assign 536 people to either the intervention group or the control group [19]. In brief, we generated a randomization list using simple randomisation (unstratified, no blocking) functions, and placed sealed envelopes representing the order of allocation into a box for the recruiters.…”

“…One trial visit for the intervention group and one for the control group was planned at baseline and after 1 year [19]. The invitation procedures for these visits were similar to those for the intensive screening procedures.…”

Risk perception is not associated with attendance at a preventive intervention for type 2 diabetes mellitus among South Asians at risk of diabetes

“…This could be supplemented with a family session, two group-based cooking classes and a supervised PA programme, as described previously (5,24) . All participants were contacted by letter and by telephone and were referred to a study dietitian near their place of residence.…”