Association between muscle fatigability and diabetic kidney disease complications in patients with type 2 diabetes

Aims: Type 2 diabetes mellitus (T2DM) requires the maintenance of high physical activity levels and specific interventions tailored to the characteristics of each patient. We hypothesized that T2DM combined with diabetic kidney disease (DKD) could increase muscle fatigability, becoming a specific contributor to physical inactivity. This study aimed to determine the association between muscle fatigability and DKD complications and investigate the relationship between muscle fatigability and physical activity in patients with T2DM. Methods: Overall, 50 patients with T2DM aged 40-65 years and with an estimated glomerular filtration rate of 30 mL/min/1.73 m2 or higher were included. Muscle function was assessed using an isokinetic dynamometer. Muscle fatigability (maximal voluntary concentric contraction [Delta MVCC] velocity, maximal voluntary isometric contraction [Delta MVIC] torque), which indicated the decrease in angular velocity and muscle strength associated with the exercise task, was calculated. The patient characteristics, physical activity (IPAQ-SV), knee extensor strength, and skeletal muscle index were evaluated. Participants were divided into two groups (DKD and nonDKD) according to the presence of DKD, and Delta MVCC velocity and Delta MVIC torque were compared. Results: Delta MVCC velocity was significantly higher in the DKD group than in the non-DKD group (p < 0.05). Similarly, Delta MVIC torque was significantly higher in the DKD group than in the non-DKD group (p < 0.05). Subgroup analyses showed that Delta MVCC velocity was independently associated with physical activity in the DKD group (odds ratio: 0.93, 95 % confidence interval: 0.88-0.99). Conclusions: Muscle fatigability increased with DKD in patients with T2DM and might be related to physical activity.