Pattern of Thyroid Functional Derangements in Patients with Metabolic Syndrome

Aim: To study the pattern of thyroid functional derangements in patients with metabolic syndrome. Methods: The current study was designed as a cross sectional descriptive study of 130 patients with metabolic syndrome. Results: The mean age was 57.5, with 88 [67.69%] females. According to HOMA-IR estimation; 129 (99.2%) of the studied patients were found to have insulin resistance. Subclinical hypothyroidism was diagnosed in 34 (26.15%). There was no age or sex difference between patients with and without subclinical hypothyroidism however a significant higher prevalence of dyslipidemia (high triglyceride, 25[73.53%] vs. 33[34.38%,], p=0.001) and (low HDL-C, 34[100%] VS. 81[84.38%], P=0.01) in patients with compared to without subclinical hypothyroidism respectively. Also, the mean ± SD waist circumference (138.6 cm ± 1.4 vs 118.9 ± 9.9, p=0.001) and waist/hip ratio (1.24 ± 0.08 vs. 1.098 ± 0.09, p= 0.001) were significantly higher in patients with compared to without subclinical hypothyroidism respectively. There was no statistically significant difference between the two groups regarding HOMA-IR. In addition, there was no significant correlation between HOMA-IR and either free thyroxine (FT4) or thyroid stimulating hormone (TSH). However, TSH was significantly positively correlated with triglycerides; R= 0.2, P=0.02 and negatively correlated with HDL-C; R=-.02, P=0.01. There was significant strong positive correlation between TSH and obesity parameters (waist circumference; R=0.6, P=0.001 and waist/hip ratio; R=0.5, P=0.001), while a significant negative correlation was found between FT4 and fasting insulin; R= -0.2, 0.04, waist circumference; R= -0.2, P=0.01 and waist hip ratio; R= -0.3, P=0.002. The area under the ROC (95% CI) was 0.93 (0.88-0.97), P=0.001 for the waist circumference as a predictor of subclinical hypothyroidism with a sensitivity of 97% and specificity of 81%, while that of waist / hip ratio was 0.86 (0.79-0.91), p=0.001, with a sensitivity of 91% and specificity of 77%. Conclusion: Subclinical hypothyroidism is prevalent among patients with metabolic syndrome. TSH is significantly associated with metabolic syndrome parameters particularly dyslipidemia and obesity indicators.