Background: Urinary titin N-terminal fragment concentration (urinary titin) has been reported to be negatively correlated with muscle mass, grip strength, and knee joint extension strength, and is considered a biomarker that reflects sarcopenia, muscle damage, and the catabolic state of muscle. Sarcopenia and skeletal muscle dysfunction occur in the person with diabetes, but it is unclear how urinary titin changes with improved blood glucose control.

Methods: One hundred and five Japanese patients with diabetes (85 type 2 and 20 type 1) who were hospitalized for glycemic control for approximately 2 weeks were included. Patients who were hospitalized with acute complications of diabetes or who had infections were excluded. Urinary titin was measured in all patients at admission and discharge, and skeletal muscle mass index (SMI) was measured in 49 patients.

Results: Patients were 55 males and 50 females. Median age was 62.0 years, BMI was 25.5, and HbA1c was 9.2%. There was no correlation between urinary titin at admission and age, BMI, SMI, and HbA1c, but it tended to be higher in men (p=0.08). Urinary titin was 2.31±5.40 nmol/gCr at admission and 1.30±1.48 nmol/gCr at discharge, showing a significant decrease (p=0.049). Body weight loss of -1.8% was observed during hospitalization, and SMI decreased by -1.4% from admission. There was no correlation between changes in urinary titin during hospitalization and age, BMI, HbA1c, and changes in body weight and SMI during hospitalization.

Conclusion: Urinary titin significantly decreased in patients with diabetes who were hospitalized for glycemic control for approximately 2 weeks, and no correlation was observed with changes in SMI. The short-term changes in urinary titin suggested that skeletal muscle dysfunction was improved by improvement of blood glucose control. However, in this study, the quality of skeletal muscle such as muscle strength could not be evaluated, and additional examination is necessary.

Disclosure

S.Yoshida: None.

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