Effectiveness of Culture-Specific Diabetes Care for Surinam South Asian Patients in the Hague: A randomized controlled trial/controlled before-and-after study

An extremely high prevalence of diabetes has been found among South Asians, especially among immigrants living in a western society (1). In the Hague, we found a high prevalence of diabetes among South Asians from Surinam (2). Because usual diabetes care had insufficient affinity with the cultural and culinary traditions of this population, a new culture-specific type of care was developed. We investigated whether this intervention led to a decrease in HbA_1c level, an improvement in lipid profile, or a decrease in BMI.

The intervention consisted of the referral of South Asian patients by their attending physician to a specialist diabetes nurse and a dietitian. These care providers received training to improve their knowledge of the South Asian cultural and culinary traditions. They made use of newly developed educational materials consisting of an audio-cassette containing general diabetes information recorded in the Surinam-Hindi language and two booklets, one containing general information on nutrition and another containing a carbohydrate variation list; both were based on South Asian cooking. It was expected that the advice from the dietitian would be more applicable, among other things, because of the information concerning calorie-equivalent dishes contained in the carbohydrate variation list. It was also expected that the interaction between patients and care providers would improve, resulting in improved compliance with therapy. The diabetes education provided by the nurses and dieticians consisted of intensive guidance (∼4–7 visits) for 3 months, after which the patients continued to receive guidance from these care providers but with longer intervals.

The intervention study was carried out in three general practices (eight general practitioners) and an outpatient clinic. All Surinam South Asian patients known to have type 2 diabetes, with no comorbidity interfering with the interpretation of metabolic control (e.g., recent myocardial infarction or dementia), and who visited their attending physician during the first half of 1998, were included in the study.

The first part of the study was a randomized controlled trial (RCT), in which the patients were randomized based on date of birth: odd numbers (intervention patients, n = 53) and even numbers (waiting-list control patients, n = 60). The only parameter of the RCT was the difference in the change in the HbA_1c level immediately after the intensive guidance of the intervention patients.

After 6 months, the control patients were also given the opportunity to benefit from the new type of care. Of these 60 patients, 28 who were no longer under the control of the same physician or who could only be sent a written invitation did not participate. Together with the remaining 32 waiting-list control patients and the 53 intervention patients, 4 other patients were included in the second part of the study. This was a controlled before-and-after study (CBA), thus including 89 patients. The CBA study consisted of a pretest measurement of HbA_1c, BMI, and lipid profile; a measurement of HbA_1c and BMI immediately after the period of intensive guidance; and a second post test measurement of HbA_1c, BMI, and lipid profile (values known from 53–76%) 1 year later. The t test was used to answer the research questions.

In the RCT, the average age was 51.7 vs. 54.8 years, the male-to-female ratio was 26 of 27 vs. 31 of 29, and the initial HbA_1c level was 8.4 vs. 8.2% for intervention vs. control patients, respectively. A difference of 0.42% (P = 0.02) was found in the average change in HbA_1c level, in favor of the intervention patients. After controlling for differences in age, sex, and initial HbA_1c, the difference between groups was 0.50% (P = 0.004). The change was greatest in the subgroup of patients who had never previously received diabetes education. When considering only those patients with an initial HbA_1c level >7.5%, the difference was 0.69% (35 intervention and 35 control patients; P = 0.003).

In the CBA, the change in HbA_1c level was smaller (0.29%) because of a more modest result among the waiting-list control patients who started their participation after the completion of the RCT. BMI decreased by only 0.04 kg/m². One year later, this had not essentially changed. No relation was found between changes in BMI and HbA_1c. After 1 year, the lipid profile improved significantly; total cholesterol decreased by 0.56 mmol/l (P < 0.0005), total cholesterol–to–HDL ratio decreased by 0.54 mmol/l (P = 0.001), and triglycerides decreased by 0.34 mmol/l (P = 0.002).

In one general practice, for financial reasons, there was no continuity in the new type of care. Considering the data of the 19 patients of this practice with a known HbA_1c level 1 year later, the improvement had disappeared almost entirely. In contrast, improvement was maintained in the other three practices.

This study has shown that the development of culture-specific diabetes care can have a beneficial effect on metabolic control. It is probable that this effect is partially caused by the fact that contact was made with a group of patients that had not been contacted before. Continuity in the provision of this care appears to be crucial for a lasting effect.

With respect to the two above-mentioned possible active mechanisms, improvement in the applicability of nutritional advice should, in particular, be reflected in calorie intake. However, little improvement was found in BMI, and no relation between changes in BMI and HbA_1c was found. Therefore, the results suggest that the improvements in HbA_1c and lipid profile were mainly achieved by better interaction between care providers and patients, which may have led to better compliance, not only with regard to medication, but possibly with regard to physical activity and nutrition (e.g., a better distribution of meal times).

Effects of the intervention program are described as being particularly favorable if an important role is attributed to the nursing staff and if considerable emphasis is put on patient education (3). Both of these characteristics apply to the present intervention.

Research was restricted to only a few practice settings and a small number of care providers. This could possibly limit the generalizability of the study results. Currently, intramural- and extramural-employed diabetes nurses and dieticians in the Hague are providing this new type of care. Further research will determine whether similar results are achieved with Surinam South Asian diabetes patients.