The main objective of this study is to determine the effectiveness of a targeted prevention programme to prevent DM, and in the long-term DM-related morbidity, among 18-60 year old Hindustani Surinamese:1. What is the effectiveness of a targeted prevention programme, consisting of screening for pre-diabetes and DM and a targeted lifestyle intervention to prevent DM among persons with pre-diabetes? 2. What are the costs vs. benefits of the prevention programme?3. What are the potential side- effects of the prevention programme?More specifically:Ad 1. How many persons with pre-diabetes or DM are identified?What is an appropriate age range and time interval for screening in this population: what is the prevalence of pre-diabetes and DM at baseline and what is the incidence of pre-diabetes and DM after three years among those with normoglycemia at baseline? Can criteria based on (biomedical) determinants be used for the identification of pre-diabetes and DM, as an alternative to the oral glucose tolerance test (OGTT)?How effective is the lifestyle intervention among Hindustani persons with pre-diabetes in preventing incident cases of DM? What is the effect of the intervention on intermediate outcomes (e.g. motivation, diet, physical activity) during and after the programme? How effective is the lifestyle intervention with regard to secondary outcomes (e.g. plasma glucose levels, blood pressure levels, lipid profile, microalbuminuria, heart rate and weight)?What are the determinants of the effect of the intervention on the primary, secondary and intermediate outcomes?Ad 2. What are the benefits of the prevention programme in terms of averted cases of DM? What are the costs of the prevention programme per case averted? What are the organisational requirements of the prevention programme? Ad 3. What is the effect of the prevention programme on the quality of life (e.g. stress, anxiety) of persons with normoglycemia, pre-diabetes and newly diagnosed DM?Is there an increase of decrease in healthcare contacts, related to the prevention programme?This study will build on the results of previous work. In the present study we will assess the effectiveness of the targeted prevention programme that was developed and shown to be feasible in a previous feasibility study among the Hindustani population [(Zonmw project 6130.0034), unpublished].
Type 2 diabetes mellitus (DM) is one of the most common chronic diseases and is associated with long-term morbidity, such as retinopathy, renal failure and, in particular, cardiovascular disease. Prevention of new DM cases and DM-related morbidity could lead to important health gain. In the Netherlands, a particularly high prevalence of DM is found among Hindustani: the prevalence among the Hindustani is four times as high as that among the ethnic Dutch in the same age group. In accordance, studies have shown that the prevalence of pre-diabetes, characterised by impaired fasting glucose (5.6-7.0 mmol/l) or impaired glucose tolerance (2-h OGTT value 7.8 -11.1 mmol/l), is also high in the Hindustani populations. Persons with pre-diabetes are at high risk of developing DM and DM-related morbidity. Previous studies have convincingly shown that intensive lifestyle interventions prevent the onset of DM among persons with pre-diabetes. However, the effectiveness of interventions depends on the characteristics of the population studied and the strategy used. In general, interventions aimed at the general (white) population are less effective in specific migrant groups, such as the Hindustani. Therefore, prevention programmes for DM among the Hindustani population should be targeted to the characteristics of that population.In a recent feasibility study, we have developed such a prevention programme for the Hindustani population, which consists of a targeted screening and a targeted lifestyle intervention [(Zonmw project 6130.0034), unpublished]. The design of this programme takes the specific epidemiological and cultural characteristics of the Hindustani population into account. An initial evaluation showed that the intensive, targeted approach used is successful: 43% of all eligible persons were screened. Of those, 40% had pre-diabetes and were eligible for the lifestyle intervention. However, prior to further implementation of this programme, insight into the effectiveness is needed. Specifically, what is the effectiveness of a targeted prevention programme with regard to the prevention of DM and in the long-term- DM-related morbidity, what are the costs vs. benefits, and what are the side-effects of the prevention programme?To investigate these issues, we will invite approximately 6000 Hindustani Surinamese men and women aged 18-60 to be screened by means of a fasting plasma glucose measurement and oral glucose tolerance test. Participants with pre-diabetes (n=500) will subsequently be invited for a randomised controlled trial in which a group receiving the intensive lifestyle intervention will be compared with a control group receiving simple, generic lifestyle advice. In case of suspected DM, participants will be referred to their GP for care. Moreover, a sample of those with normoglycemia at baseline will be invited for re-screening after 3 years.The lifestyle intervention consists of individual dietary counselling, supplemented with group sessions aimed at the social environment and a supervised exercise programme. The content of the intervention has been adjusted to reflect prevalent dietary behaviours (e.g. irregular meal pattern), physical activity preferences (e.g. fitness and dancing), motivational factors (e.g. sessions to decrease the (perceived) social pressure) and barriers (e.g. women-only facilities).To evaluate the effectiveness of the intervention, data will be collected on fasting glucose, HbA1c, insulin and post-load glucose concentrations at baseline and at 12, 24 and 36 months. Moreover, changes in physical fitness and cardiovascular risk profile will be measured. In addition, data on self-reported physical activity, dietary behaviour, motivational factors, quality of life and other measures will be collected using structured interviews. Furthermore, each patient will be asked to record the direct costs, including for example the costs of transportation and the purchase of sports gear, in a diary. The direct non-medical costs, the indirect costs and the time investment of professionals in the programme will also be determined. The design and data collection procedures for this study have been developed in the aforementioned feasibility study. Therefore, the proposed study, which matches several priorities of the ZonMW Prevention Programme, will be able to benefit from the knowledge gained and the organisational arrangements that were already made. In conclusion, this study will provide an important contribution to preventive strategies and guidelines aimed at reducing the burden of DM and DM-related morbidity. On the basis of the information obtained on the effectiveness and costs, recommendations will be made for the wider implementation of the prevention programme in the Hindustani Surinamese population in the Netherlands. |
