Evaluation of Skin and Subcutaneous Adipose Tissue Thickness for Optimal Insulin Injection

Abstract

Patient’s skin and subcutaneous adipose tissue thicknesses are the primary criteria that determine the optimal insulin needle length in subcutaneous insulin treatment. The present study aims to measure skin thickness and subcutaneous adipose tissue thickness in patients with diabetes mellitus and to investigate the association of these measurements with waist circumference and body mass index. The study included 449 subjects (152 patients with DM and 297 healthy controls, mean age: 44.58 ± 14.25 year) aged 18 years or older. The primary endpoint was the time of comparison of skin thicknesses and subcutaneous adipose tissue thicknesses between patients with diabetes mellitus and healthy subjects and the secondary endpoint was the time of assessment of the relationship between skin and subcutaneous adipose tissue thicknesses and body mass index and waist circumference. Skin and subcutaneous adipose tissue thicknesses were measured by ultrasonography. Overall, average skin thickness values were 1.95 mm (1.05-3.92) for triceps, 2.35 mm (1.07-3.82) for anterior abdomen and 1.97 mm (1.12-3.12) for anterior thigh, while subcutaneous adipose tissue thicknesses were 6.42 mm (1.01-33.5) for triceps, 15.73 mm (1.04-39.3) for anterior abdomen and 7.92 mm (1.48-31.6) for anterior thigh. Triceps and anterior thigh skin thickness values were higher in the diabetes mellitus group compared to healthy controls (p<0.01 for both) while subcutaneous adipose tissue thicknesses were similar between the two groups. There was a positive correlation between body mass index and waist circumference and between skin and subcutaneous adipose tissue thicknesses (p<0.01 for both). The largest skin thickness measured in the present study was 3.92 mm, which supports the previous reports that short needle tips could be used safely in individuals with diabetes mellitus.