Effectiveness of a self-regulation intervention for non-western immigrants with a high risk for cardiometabolic disease

Background: Various non-western immigrant populations have a high risk for cardiometabolic disease and tend to benefit less from existing lifestyle interventions. The Intervention Mapping Protocol was applied to develop a culturally tailored self-regulation intervention. Methods: 193 non-western immigrants in the Netherlands were randomized in an open trial to receive the intervention or regular care at the GP’s office. The intervention, consisting of a home visit, four group consultations, and two telephone consultations, was delivered by Community Health Workers (CHWs) and focused on improving self-regulation skills. Linear and logistic regression models were used to evaluate effects at 3 months after the intervention period. Results: Only 102 participants completed follow-up measures with similar drop-out rates in both groups. The intervention was very well received: Participants graded the intervention with an average score of 8.1 (SD=1.1) and the CHWs with an average score of 8.8 (SD=0.9) on a 10-points scale. However, preliminary results show no effect of the intervention regarding cardiometabolic risk factors (e.g., BMI, β=0.013, 95% CI [-0.50,0.75]; systolic blood pressure, β=0.088, 95% CI [-2.87,8.02]; diastolic blood pressure, β=-.050, 95% CI [-4.57,2.54]), or health behaviours (e.g., activity score β=-.054, 95% CI [-2.87,1.76]). Discussion: This theory-based self-regulation intervention for non-western immigrants was carefully tailored to the needs of the target population. However, the intervention did not improve cardiometabolic risk factors and health behaviours. Currently, process evaluations are conducted to better understand the lack of effectiveness and how this may be related to the high non-response rate and participants’ personal health goals.