Endocrine Abstracts

Background: Thyroid dysfunction is associated with increased cardiovascular morbidity and mortality. Early detection may influence the clinical management of the patients. There is insufficient data about the prevalence and clinical significance of thyroid dysfunction in cardiovascular hospitalized patients.

Aims: To study the prevalence of thyroid dysfunction in cardiovascular hospitalized patients, to characterize patients with high prevalence of thyroid dysfunction and to determine the mortality rate of this population.

Methods: A retrospective analysis of a medical records database of all adult patients admitted not-electively to the Cardiology Department at Shaare-Zedek Medical Center, Israel, between 2005–2017. Blood test for Thyroid Stimulating Hormone (TSH) level was performed as a routine test in all patients, and T4 and T3 levels were checked according to TSH result. Statistical analysis was performed on demographic and clinical characteristics, as well as mortality data, of the entire cohort.

Results: During the described period there were 19281 non-elective hospitalizations of 14388 patients. TSH was available for 14384 patients during their first hospitalization. The mean age was 67±15. Thyroid dysfunction was present in 10% of the patients (2% TSH>10 mIU/L; 5% TSH 5–10 mIU/L; 2% TSH 0.1–0.35 mIU/L; 1% TSH <0.1 mIU/L). The prevalence of thyroid dysfunction was significantly higher in elderly patients (age>70 y; prevalence 12.1%, Odds ratio[OR]=1.4) and in patients with atrial flutter/fibrillation (14%, OR=1.4), pulmonary hypertension (14%, OR=1.4), chronic renal failure (14%, OR=1.5), heart failure (15%, OR=1.5), hypothyroidism treated with Levothyroxin (28%, OR=3.3) and patients treated with Amiodarone (24%, OR=3). Adjusted multivariable analysis showed increased mortality during the study period, for TSH<0.35 mIU/L, TSH 5-10 mIU/L and TSH>10 mIU/L (hazard ratio 1.44, 1.27 and 1.4, respectively).

Conclusion: The prevalence of thyroid dysfunction in cardiac hospitalized patients is 10% and is even higher in specific patient-groups. Thyroid dysfunction is associated with an increased mortality rate. Screening for thyroid function may be considered in cardiology departments, especially for selected high risk groups.