Short-term effects of group-based nutritional education on nutritional adherence and glycaemic control in outpatients with type 2 diabetes: a randomised clinical trial

The objective of this study was to evaluate the impact of incorporating group-based nutritional education into usual care on adherence to nutritional counselling among outpatients with type 2 diabetes (T2DM). This parallel-group, randomised controlled superiority trial was conducted with outpatients diagnosed with T2DM and poor glycaemic control. The control group received individual usual care, while the intervention group received usual care plus group-based nutritional education, which included three sessions: 'Let's Go Shopping,' 'Healthy Plate' and 'Hunger and Satiety.' Baseline and four-month follow-up assessments were conducted, and outcome measures included adherence to nutritional counselling, glycaemic control, weight and physical activity. A total of 213 participants were included: 61·9 % were women, aged 60 years (interquartile range (IQR) = 53-65), 67·6 % with low socio-economic status, 67·3 % had obesity and the glycated Hb (HbA1c) was 9·3 % (IQR = 8·3-10·2 %). The intervention did not result in superior glycaemic control; however, short-term reductions in HbA1c were observed across all participants (-0·3 % (IQR = -0·7-0·3 %)). The intervention group demonstrated an increase in physical activity levels between visits (262 metabolic equivalent tasks (IQR = 99-257); <i>P</i> = 0·038), but no significant difference between the groups. Participants in the intervention group adhered to 67 % of combinations, compared with 50 % in the control group (<i>P</i> = 0·012), and adherence to the diabetes plate method was significantly higher in this group (75·9 % <i>v</i>. 62·2 %; <i>P</i> = 0·05). In conclusion, no significant between-group differences in glycaemic control were found, although both groups improved HbA1c short-term. Group-based nutritional education increased dietary adherence, particularly to the diabetes plate method and physical activity. Long-term effects on metabolic outcomes warrant further study.