EFFECT SOME ENVIRONMENTAL FACTORS ON AUTOANTIBODIES LEVELS ON IRAQI PATIENTS WITH HASHIMOTO HYPOTHYROIDISM

Abstract

Background: Hashimoto’s thyroiditis (HT) is a common autoimmune thyroid disorder characterized by the gradual destruction of the thyroid gland. It is influenced by a complex interplay of genetic, environmental, and lifestyle factors. Among these, environmental triggers such as smoking, dietary patterns, psychosocial stress, and vitamin D3 deficiency are increasingly recognized for their potential to modulate thyroid autoimmunity. Iraq, with its unique environmental and dietary conditions, presents a valuable context to investigate these associations.

Objective: To evaluate the relationship between key environmental factors—specifically smoking, dietary habits (iodine and gluten intake), psychosocial stress, and vitamin D3 levels—and the profiles of thyroid autoantibodies in Iraqi patients diagnosed with HT.

Methodology: This cross-sectional study enrolled 96 Iraqi patients (38 males, 58 females) diagnosed with HT from December 2023 to December 2024 in Baghdad. Data on lifestyle and dietary habits were collected through structured interviews. Laboratory assessments included measurements of thyroid hormones (T3, T4, TSH) and autoantibodies (Anti-thyroglobulin [Anti-TG], Anti-thyroid peroxidase [Anti-TPO], and TSH receptor antibody [TRAb]) using ECLIA and CMIA analyzers. Statistical analyses included chi-square tests and logistic regression models to identify associations.

Results: Female patients demonstrated a higher prevalence of Anti-TPO positivity (75%) than males (55%). Smoking, more frequent among males, was significantly associated with lower TRAb levels. While all participants consumed iodine-rich diets, 85% also followed gluten-rich diets. Vitamin D3 deficiency was observed in over 40% of participants, though it was not significantly associated with autoantibody levels. Gluten intake showed a mild association with T4 levels. Psychosocial stress had no significant impact on thyroid biomarkers. Notably, Anti-TPO levels showed a positive correlation with patient age.

Conclusion: Environmental factors, particularly smoking and dietary habits, appear to influence thyroid autoimmunity in Iraqi HT patients. Public health interventions focusing on smoking cessation and dietary management may contribute to better disease control. Further prospective studies are needed to confirm these findings.