Your Lifestyle As Medicine: the impact of a citizen initiative for people with type 2 diabetes using peer coaching and self-management.

Background and aim: Sustained lifestyle changes are crucial for the remission of type 2 diabetes (T2D) but remain challenging. Citizen initiatives using peer coaching and self-management may offer a promising alternative to professional medical care. This study evaluated Your Lifestyle As Medicine (YLAM), a Dutch citizen initiative for people with T2D. We aimed to assess its impact on metabolic parameters and to examine participants' engagement. Methods: This observational study analysed self-reported data on weight, waist circumference, fasting glucose and glycated haemoglobin (HbA1c) from participants in YLAM's online community. Participants could report their self-measured data on a weekly basis. Linear mixed-model analyses, stratified by sex, were used to assess changes in metabolic parameters over time. Additionally, we evaluated participants' engagement through reporting duration and weekly reporting rates. Results: We assessed all 232 people with T2D who reported multiple measurements for at least 3 months. The median reporting duration was 11.2 months (IQR 4.6-26.5). Weekly reporting rates were 59% for weight, 55% for waist circumference and 52% for fasting glucose, and 12-weekly reporting rates were 49% for HbA1c. Overall, mean weight, waist circumference, fasting glucose and HbA1c improved in the first year in both women and men. More specifically, weight decreased by 7.2 kg in women (95% CI -7.6 to -6.8) and by 7.4 kg in men (95% CI -8.0 to -6.8). This represented a mean relative weight loss of 9.0% (SD 7.7) and 8.6% (SD 6.5), respectively. Waist circumference decreased by 8.9 cm in women (95% CI -9.4 to -8.5) and by 8.5 cm in men (95% CI -9.1 to -7.8). Fasting glucose decreased by 1.15 mmol/L in women (95% CI -1.32 to -0.98) and by 0.49 mmol/L in men (95% CI -0.75 to -0.23). HbA1c decreased by 14.5 mmol/mol in women (95% CI -17.4 to -11.6) and by 9.1 mmol/mol in men (95% CI -13.2 to -5.0). Of all participants, 44% reported data for longer than a year and demonstrated sustained improvements in weight and waist circumference in the long term. Conclusion: This study provides evidence for substantial and sustained improvements in self-reported metabolic parameters in people with T2D engaged in a citizen initiative without medical supervision. Initiatives like YLAM offer a promising, accessible and scalable strategy to address the growing burden of lifestyle-related diseases.