Unravelling thyroid dysfunction in rheumatoid arthritis: History matters

Autoimmune thyroid disease (AITD) frequently coexists with other systemic autoimmune conditions such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Due to the overlapping and nonspecific nature of symptoms, it is difficult to clinically uncover thyroidal illnesses in RA patients. This study was conducted to estimate the prevalence of thyroid dysfunction including the presence of anti-thyroid peroxidase (antiTPO) autoantibodies in patients with RA and to analyze symptomatology of thyroid dysfunction in patients diagnosed with RA.

This cross-sectional, prospective study was conducted on 100 patients with RA, attending the Rheumatology Outpatient Department at St John's Medical College and Hospital, Bangalore, India.

Twenty-two patients had biochemical evidence of thyroid dysfunction, hypothyroidism being the commonest (15/22 patients). Although fatigue and hair loss were the most common symptoms, only weight gain and cold intolerance were found to be statistically significant (P < 0.05) predictors of hypothyroidism and 32 patients were antiTPO positive. It was observed that equal numbers of patients developed hypothyroidism after diagnosis of RA and vice versa.

History taking at the bedside to elicit symptoms, especially weight gain and cold intolerance, is quintessential to ensure timely diagnosis of hypothyroidism.