Subacute thyroiditis(SAT) is an acute inflammatory, self-limited, and destructive disease of the thyroid gland. Although it is a temporary disease, it has permanent consequences. We aim to investigate the influences of the treatment choice on permanent hypothyroidism occurring after SAT and whether there are predictive factors for the development of permanent hypothyroidism.
We retrospectively investigated 57 SAT patients admitted to our tertiary hospital between 2017 and 2019. After excluding 6 patients, demographic, clinical, laboratory, and imaging findings of 36 patients treated with NSAIDs and 15 patients treated with corticosteroids were compared. The median duration of follow-up was 4 (3.5-5.5) years.
Permanent hypothyroidism occurred in 16 patients (31.4%) of 51 patients. It developed at a significantly higher rate in NSAID users (p=0.019). There was no significant difference in the occurrence of transient hypothyroidism and recurrence (p=0.472, p=0.082). The early maximum TSH values were strongly associated with permanent hypothyroidism. The Odds Ratio (OR) value was 2.59 (95% CI = 1.26 – 5.33, p=0.009), Nagelkerke R2 = 0.821. The early maximum TSH level had a predictive value, with an AUC of 0.966 for post-SAT permanent hypothyroidism (p<0.001). The cutoff values for the early maximum TSH were 9.07uIU/ml (81.3% sensitivity, 100% specificity), and 7.05 uIU/ml (87.5% sensitivity, 94.3% specificity).
Corticosteroid therapy is significantly effective in preventing permanent hypothyroidism from developing after SAT. The early maximum TSH values are an indicator for the prediction of the development of permanent hypothyroidism.