Correlation of Serum Uric Acid, Thyroid-Stimulating Hormone and Free- Thyroxine in Subclinical and Overt Hypothyroidism

Abstract

Objective: To correlate the serum uric acid, Thyroid-stimulating hormone (TSH) and free-thyroxine (FT4) in overt and subclinical hypothyroidism. Study Design: Cross sectional comparative. Place and Duration of Study: Capital Development Hospital, Islamabad from January 2019 to June 2019. Materials and Methods: Total 114 participants, recruited through convenient non-probability sampling technique, were sub-divided in three groups, comprising 38 participants each. Group I included patients of overt hypothyroidism. Group II had patients with subclinical hypothyroidism and Group III included healthy controls. Serum uric acid levels were measured for all participants. For data analysis, SPSS 21 was used. Statistical significance was estimated using one way ANOVA. p value of < 0.05 was considered significant. Correlation between numerical variables was determined by Pearson correlation coefficient. Results: Mean serum uric acid level in overt hypothyroid patients (7.5±0.84 mg/dL) was significantly raised than the patients in the subclinical hypothyroid and control group (4.7±0.82, 4.6±1.09 mg/dL respectively) with p value <0.001. However, there was no significant difference of mean uric acid levels between subclinical hypothyroid group and the control group (p value =0.95). A significantly positive relation was observed between serum uric acid and TSH in group I only (r = 0.53 and p < 0.001). Conclusion: Uric acids levels are increased in hypothyroidism more profoundly in case of overt hypothyroidism, less so when subclinical hypothyroidism is present. In patients of overt hypothyroidism, serum TSH and uric acid levels should be monitored regularly to prevent renal complications in these patients.

Keywords

• hypothyroidism, thyroid stimulating hormone, thyroxine, uric acid.