Association of short-term changes in HbA1c with body composition and the importance of muscle maintenance in patients with Type 2 diabetes

Aims: This study aimed to investigate the relationship between changes in glucose metabolism and body composition in patients with diabetes. Methods: We included 380 patients with type 2 diabetes, who underwent bioelectrical impedance analysis, in this longitudinal study. Changes in HbA1c (Delta HbA1c) levels and body composition indices were compared between baseline and 6 months. A multivariate analysis was performed to examine the relationship between Delta HbA1c and changes in body composition. Results: HbA1c levels were significantly decreased at 6 months (P < 0.01), but there was no significant change in BMI. A linear multiple regression analysis showed that Delta HbA1c was negatively correlated with changes in muscle mass (beta = -0.18; P = 0.047) and bone mineral content (beta = -0.28; P < 0.001), but there was no significant association between Delta HbA1c levels and a change in body fat percentage. Conclusions: This study shows a limited association between short-term changes in glucose metabolism and changes in body composition in patients with type 2 diabetes. Therefore, interventions aimed at reducing adiposity may not affect glucose metabolism in the short term, while interventions focused on maintaining or enhancing muscle mass and bone mineral content may play an important role in diabetes management.