Journal of Advances in Medical and Biomedical Research

en Risk Factors Associated with Early-Onset Type 1 Diabetes Mellitus in Children Under Five Years: A Cross-Sectional Study in Yazd, Iran Clinical Medicine Clinical Medicine مقاله پژوهشی Original Research Article Background: Type 1 diabetes mellitus (T1DM) is a common autoimmune disease in children. Recent trends show a declining age of onset, raising concerns about contributing factors. This study identified factors associated with T1DM in children under five in Yazd, Iran. Methods: In this cross-sectional study, 108 newly diagnosed T1DM patients registered in Iran's Rare Diseases Foundation between March 2020 and March 2024 were analyzed. Participants were divided into two groups based on age at diagnosis: ≤5 years and >5 years. Data on genetic history, pregnancy-related, neonatal, and childhood factors were collected via standardized checklists and parent interviews. Statistical analyses including logistic regression, were performed to evaluate associations with early-onset T1DM. Results: Of the participants, 22.2% were diagnosed at or before five years of age. Maternal infection during pregnancy was significantly more common among early-onset cases (20.8% vs. 4.8%, p=0.025), increasing odds of early diagnosis by 5.26 times. Introducing cow’s milk at or after one year of age was protective against early T1DM (OR= 0.07, p=0.027). Other factors showed no significant differences. Conclusion: Maternal infections during pregnancy and early introduction of cow’s milk, are key factors linked to early-onset T1DM in children under five. These findings highlight prenatal, nutritional, and metabolic influences on early T1DM development and emphasize the need for targeted prevention strategies.   Type 1 diabetes mellitus, Risk factors, Childhood 7 7 http://journal.zums.ac.ir/browse.php?a_code=A-10-7419-1&slc_lang=en&sid=1 Nasim Namiranian 5200319475328460088359 5200319475328460088359 No 1. Diabetes Research Center, Non-Communicable Diseases Research Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Naserali Mirhosseini 5200319475328460088360 5200319475328460088360 No Pediatric Endocrinology, Department of Pediatrics, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Zohre Foroozanfar 5200319475328460088361 5200319475328460088361 No 1. Diabetes Research Center, Non-Communicable Diseases Research Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Arefe Khaki 5200319475328460088362 5200319475328460088362 No 1. Diabetes Research Center, Non-Communicable Diseases Research Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Hassan ali Mahmoudi Kohani a.mahmoodi2008@gmail.com 5200319475328460088363 5200319475328460088363 No Diabetes Research Center, Non-Communicable Diseases Research Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. Nastaran Injinari nastaraninjinari@gmail.com 5200319475328460088364 5200319475328460088364 Yes Diabetes Research Center, Non-Communicable Diseases Research Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.