Effect of a digital health behaviour change support system on cardiovascular disease risk in a randomized weight loss trial

Abstract Obesity is a risk factor for cardiovascular diseases (CVD). We evaluated a 52-week digital Health Behaviour Change Support System (HBCSS) with a one-year follow-up to treat overweight and Class I obesity. A total of 532 participants (BMI 27–35 kg/m 2 ) were randomized into three groups: CBT-based group counselling and self-help guidance (SHG) delivered face-to-face, and usual care. These groups were further divided into HBCSS and non-HBCSS groups. The 10-year CVD risks were assessed using the FINRISK calculator. Baseline median overall CVD risks were similar between groups. In two-group analyses comparing HBCSS and non-HBCSS groups, after 12 months, CVD risks decreased in both groups. However, after 24 months, only the HBCSS group maintained significant reductions in overall risk (−0.40 percentage points, p  p  < 0.05). The HBCSS results in a decrease in CVD risk factors, which is reflected by a sustained reduction in calculated CVD risks, especially among participants with obesity.