Objective: To investigate the prevalence of thyroid autoimmunity among children and adolescents with type 1 diabetes in Kuwait.
Subjects and methods: In a mixed cross-sectional and longitudinal study, anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-TG) were measured in 232 subjects (118 males and 114 females) with type 1 diabetes.
Results: The mean age of the total study population was 10.9 ± 3.6 years (range 1-21), and the median diabetes duration was 3.9 years (range 0-16). At the initial screening, 57 out of 232 (24.6%) patients had positive antibodies, and of the remaining 175 patients, who were antibody negative,131 (74.3%) were followed up for 4-9 years. 23 out of these 131 (17.7%) patients became antibody positive, with a cumulative prevalence of elevated antibodies of 34.5%. Anti-TPO was present in 34 (14.7%), anti-TG in 23 (9.9%) and both antibodies in 23 (9.9%) patients. Thyroid antibodies presented early within the first 5 years of the onset of diabetes (63.2 vs. 36.8%, p < 0.05). The prevalence of elevated thyroid antibodies increased after the onset of puberty in both females and males (p < 0.0001). A total of 58.7% of the patients with positive antibodies were females compared to 41% males (p < 0.0001). The basal thyroid-stimulating hormone was higher in subjects with positive antibodies (5.1 ± 10.7 mIU/l) compared to those who were antibody negative (1.79 ± 0.87 mIU/l, p < 0.001). Furthermore, 30 out of 232 (12.9%) patients developed thyroid dysfunction.
Conclusion: In this study, a high prevalence of thyroid autoimmune antibodies was found in patients either at the onset of type 1 diabetes or within the 4-9 years of follow-up.