Prevalence of Thyroid Dysfunctions in Patients with Rheumatoid Arthritis at Tertiary Care Hospital

BACKGROUND: Thyroid dysfunctions frequently co-exist in patients with Autoimmune disorders like rheumatoid arthritis, systemic lupus erythematosus (SLE), and Vasculitis. Presence of thyroid dysfunctions in patients with rheumatoid arthritis increase the co-morbidities and mortality some time because of cardiovascular complications. Objective This study was conducted to determine the burden of thyroid dysfunctions in rheumatoid arthritis patients attending tertiary care hospital of Karachi, Pakistan. METHODS: A cross-sectional study was conducted at rheumatology clinic of a Jinnah Post Graduate Medical Centre in Karachi, Pakistan from April 2019 to January 2021. All diagnosed cases of rheumatoid arthritis having seronegative or seropositive rheumatoid arthritis were consecutively enrolled. Clinical records and laboratory data of these patients were collected along with outcome variables. RESULTS: Of 136 patients, thyroid abnormality was observed in 56 (41.2%) patients. In particular, 80 (58.8%) had normal, 8 (5.9%) had hypothyroidism, 14 (10.3%) had hyperthyroidism, 32 (10.5%) had subclinical hypothyroidism, and 2 (1.5%) had subclinical hyperthyroidism. A significantly lower hemoglobin levels (p-value <0.001), mean corpuscular volume (p-value 0.011), total leucocyte count (p-value 0.004), and platelet counts (p-value 0.040) were observed in patients with thyroid abnormality than those without thyroid abnormality. Furthermore, a significantly lower urea (p-value <0.001) and creatinine levels (p-value <0.001) were also observed among patients with thyroid abnormality than those without thyroid abnormality. CONCLUSION: In patients with rheumatoid arthritis, thyroid dysfunction has been shown to be highly prevalent. Subclinical hypothyroidism, the most common thyroid disorder and obvious hyperthyroidism were observed.