Correlation between uric acid and thyroid hormones in patients with thyroid disorders. A case control study

Abstract

Background: Thyroid disease influences the purine metabolism, which may increase serum uric acid (UA) level. Previous studies showed a high incidence of hyperuricemia in patients with thyroid disorders but with low thyroid stimulating hormone (TSH)-to-serum uric acid association. Objective: Aim of this work was to investigate the serum uric acid relationship to thyroid hormones in patients with primary thyroid disorder. Subjects and Methods: This case-control study included a total of 105 patients, 35 healthy participants as a control group and 70 patients with primary thyroid disorders, attending at the Endocrinology Outpatient Clinic, Kasr El Ainy, Cairo University. The included subjects were divided into three groups; (Group I) consisted of 35 patients with primary hypothyroidism, (Group II) consisted of 35 patients with primary hyperthyroidism and (group III) consisted of 35 subjects representing the control group. Waist circumference and the BMI have been calculated. TSH, free T4 (FT4; thyroxine) and free T3 (FT3; triiodothyronine), fasting lipids, creatinine, urea, eGFR and uric acid were evaluated. Results: On comparing the three studied groups a statistical significant difference in UA level was found (p < 0.05), being highest in group I followed by group II then group III (6.59± 1.32mg/ dl, 6.38± 0.88mg/ dl and 5.48± 0.47mg/ dl respectively). Among hyperthyroid patients, there was a statistical negative significant correlation between UA and TSH (r-0.733-) and a positive significant correlation between Uric acid and FT3 (r 0.541) and FT4 (r 0.482). Conclusion: A significant negative correlation between uric acid and TSH and significant positive correlation between it and FT3 and FT4 among hyperthyroid patients were found. Focusing more on the possible correlation of uric acid and primary thyroid diseases.