Insulin-induced Lipo hypertrophy and factors affecting it in children and adolescents with type 1 diabetes mellitus: Review of Literature in the past 12 years

Lipohypertrophy (LD) is one of the most common complications of subcutaneous insulin injection. Many factors are convicted in the development and progress of LD in children with T1DM. Lipodystrophy can worsen glycemic control in these children. This review aimed at summarizing these important epidemiological and clinical data to clarify the different aspects of this abnormality and its predisposing factors that are necessary for prevention, early detection, and proper management. Methods: We searched PubMed, Google Scholar, Research Gate, and Scopus for research articles related to insulin-induced LD after 2010. 28 papers were found, reviewed, and analyzed. Results: The prevalence of LD varied greatly between 17% and 75% and was significantly affected by different risk factors. The pooled prevalence of LD in children and adolescents (16 studies) was 45.16 % while the pooled prevalence in adults was 41.3%. The prevalence of LD in children appeared to be relatively higher in children compared to adults. The most critical risk factors detected in these studies included: the longer duration of diabetes and the reuse of insulin syringe > 5 times, lack of rotating insulin injection sites and or using a small area for injection, higher insulin dose/kg, the BMI, the location of injection (more LD in the abdomen, low level of patient education, higher insulin antibodies and poor control of diabetes. In addition, the method of detecting LD markedly affected the prevalence of LD. Conclusion: Improper insulin injection technique and longer duration of T1DM were the most important risk factors associated with LD. Children with LD have poorer glycemic control and require higher doses of insulin per kg compared to those without LD.