Participation in a multicomponent lifestyle intervention for people with obesity improves glycated hemoglobin (HbA_1c)

Obesity is associated with compromised glucose metabolism. Hence, it is of interest to investigate if the lifestyle interventions used in the LIBRA-cohort, which aimed at not only weight loss, but also patient well-being, could also help obese patients improve glucose metabolism by evidence of reduced HbA_1c. The aim of the study was to retrospectively investigate if patients who were referred to a lifestyle intervention for obesity, were able to alter HbA_1c.

Patients with a BMI≥30 undergoing a 6-month lifestyle intervention, who also completed physical and mental health surveys and whose baseline and 6-month blood samples were available, were included in the analysis. For changes in HbA_1c and body weight a clinically relevant change of 5≥mmom/mol and 5%≥, respectively, was chosen. Participants were divided into groups according to their baseline HbA_1c level: "Diabetes": HbA_1c of ≥6.5% (≥48 mmol/mol), "Prediabetes": HbA_1c of 5.7% to 6.4% (39-47.99 mmol/mol) or "Normal" HbA_1c <5.7% (<39 mmol/mol).

180 patients met the stated inclusion criteria and these patients were divided into groups (median age (25^th;75^th quartile): Diabetes: n=47, age 54 (43;60), 51% women, Prediabetes: n=68, age 60 (50;66), 71% women and Normal: n=65, median age 61 (50;66), 85% women. Significant reductions were found in all three groups and specifically in the diabetes group HbA_1c was reduced (mean [95%CI]) -5[-8;-2] mmol/mol from baseline to the end of the intervention. Furthermore, 35% of patients with prediabetes normalized their HbA_1c (<39) and 30% patients with diabetes reduced their HbA_1c <48. All groups had clinically relevant (≥5%) reductions in body weight (p<0.01). There was an association between body weight reduction and HbA_1c reduction in the diabetes group (p<0.01). All groups reported improvements in physical health (p<0.01).

In this retrospective cohort study, all patients achieved clinically relevant weight loss after participation in the lifestyle intervention and obese patients with diabetes achieved clinically relevant reductions in HbA_1c after 6-months. More than 1/3 of patients with prediabetes normalized their HbA_1c.