Endocrine Abstracts

Objectives: Overt hyperthyroidism is reported to be associated with an increased mortality risk and an increased risk of cardiovascular (CV) complications such as an acute coronary syndrome requiring percutaneous coronary intervention, ischemic and non-ischemic stroke, atrial fibrillation and venous thromboembolism. Increased rate of acute CV events in the course of hyperthyroidism is well documented in Graves’ disease (GD) but not in subacute thyroiditis (ST). Last year we reported three patients with an acute CV event in the course of ST. The aim of this study was to systematically compare the characteristics of hyperthyroidism and the incidence of CV events in patients with GD and ST.

Methods: Our retrospective study included 505 patients that were evaluated for overt hyperthyroidism due to GD or ST in a tertiary referral center from January 2019 to December 2020. The diagnosis of GD and ST was based on clinical evaluation, laboratory tests including measurement of TSH receptor antibodies and/or sedimentation rate, and on thyroid ultrasound. In selected cases, thyroid scan and fine neeedle aspiration biopsy were also performed. Continuous data are presented as mean (±SD).

Results: Table 1 presents the characteristics of patients with GD or ST.

In the GD group, 13 (3.3%) patients suffered a CV event within 3 months before or after the diagnosis of GD (acute coronary syndrome in 6, atrial fibrillation in 4, pulmonary thromboembolism in 2 and cerebrovascular accident in 1 patient). No CV events were registered in the ST group.

Conclusions: The patients in the GD group were significantly more hyperthyroid; in this group, there were significantly more patients with hypertension and smokers. In our cohort of patients with overt hyperthyroidism, CV events were registered only in the GD group. Acute CV events in the course of ST seem to be an extremely rare complication.