Prevalence of Thyroid Dysfunction Among Children and Adolescents in Tripoli, Western Libya: A Cross-Sectional Study

Abstract

Background: Thyroid hormones are essential for normal growth, neurodevelopment, energy metabolism, and maintenance of physiological homeostasis during childhood and adolescence. Thyroid dysfunction may present with nonspecific manifestations, and biochemical abnormalities may remain undetected without laboratory assessment. Pediatric thyroid disorders vary considerably according to age, sex, nutritional status, environmental exposure, genetic background, and population characteristics. Objective: This study aimed to determine the prevalence and distribution of biochemical thyroid hormone abnormalities among children and adolescents aged 6-15 years in Tripoli, Western Libya, and to describe their distribution according to sex and age, together with selected anthropometric characteristics, symptoms, and family history of thyroid disease. Methods: A community-based cross-sectional study was conducted among 101 children and adolescents aged 6-15 years residing in Tripoli, Western Libya. Participants were selected using a random sampling approach. Demographic and clinical information was collected using a structured questionnaire. Approximately 5 mL of venous blood was collected from each participant. Serum was separated by centrifugation and analyzed for thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine (T4) using an iFlash 1800 automated analyzer at Al-Reem Laboratory. Hormone concentrations were interpreted according to the laboratory reference intervals used in the study. Results: Among the 101 participants, 51 (50.49%) were males and 50 (49.51%) were females. Fifty-eight participants (57.42%) were aged 6-10 years and 43 (42.58%) were aged 11-15 years. The overall mean TSH concentration was 2.12 ± 1.691 µIU/mL, mean T3 was 1.32 ± 0.784 nmol/L, and mean T4 was 85.27 ± 28.542 nmol/L. TSH concentrations were within the reference range in 74 participants (73.3%), above the range in 11 (10.9%), and below the range in 16 (15.8%). T3 concentrations were within the reference range in 68 participants (67.3%), above it in 10 (9.9%), and below it in 23 (22.8%). T4 concentrations were within the reference range in 83 participants (82.2%) and below it in 18 (17.8%); no participant had a T4 concentration above the reference range. Conclusion: Most participants had TSH, T3, and T4 concentrations within the laboratory reference ranges. Nevertheless, biochemical deviations were observed in a proportion of children and adolescents. These findings provide preliminary evidence of thyroid hormone abnormalities among children in Western Libya and are broadly consistent with the only comparable community-based Libyan pediatric dataset, from Tobruk, although the proportion of abnormal results was higher in the present sample. Larger population-based studies using age- and sex-specific pediatric reference intervals and a more comprehensive thyroid profile are required.