Lipohypertrophy in insulin injecting patients with diabetes mellitus: an under-recognized barrier for glycemic control

Lipohypertrophy is the one of the commonest local complications that significantly affects glycemic control in patients of diabetes mellitus on treatment with insulin. Our study aimed at assessing the clinical and ultrasonographic characteristics and risk factors for lipohypertrophy on the abdomen in a cohort of insulin-injecting Indian diabetes patients. Eighty-eight consecutive patients with type 1 (15/88) or type 2 diabetes mellitus (73/88) were included in this cross-sectional study conducted over a period of 6 months. The prevalence of lipohypertrophy and associated risk factors was assessed by clinical examination. A novel ultrasonographic characterisation of lipohypertrophy (LH) using a predetermined grading system was performed by two sonologists who were blinded to the underlying clinical findings. Kappa statistics was used to calculate the agreement between the clinical and ultrasound methods of detection of lipohypertrophy. The prevalence of lipohypertrophy was 68% on clinical examination and 90% on ultrasonography with moderate kappa agreement (60%). The commonest patterns on clinical and ultrasonographic assessment were Grade 2 (palpable and visible − 43%) and nodular hyperechoic subcutaneous dystrophy (33%), respectively. Duration of insulin use, incorrect site rotation, and repeated needle reuse (p < 0.01) were the most important risk factors. The total daily dose of insulin (p = 0.01) and mean Hba1c (p = 0.02) were significantly higher in those with clinically detected lipohypertrophy. The needle length, caliber, the mode of delivery, or regimen of insulin used did not significantly impact development of lipohypertrophy (p = 0.15). A thorough clinical examination of insulin injection sites is of paramount importance in detecting lipohyperyrophy. Adequate control of risk factors can significantly impact insulin requirements and glycemic control, while ultrasonography can prove to be a novel and sensitive tool to detect abdominal lipohypertrophy in the majority of patients, even when clinical examination is non-contributory.