Thyroid dysfunction was associated with an increased risk of mortality in patients with heart failure due to idiopathic dilated cardiomyopathy (IDCM), according to research reported in the Journal of Clinical Endocrinology and Metabolism.

Lead author Wenyao Wang of the Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, and associates gathered data from 458 consecutive patients with IDCM who were admitted to the National Center of Cardiovascular diseases in Beijing, and then evaluated their risk of mortality based on levels of free T3 and TSH and the whole thyroid function profile.

Hypothyroidism was the strongest predictor of mortality (hazard ratio, 4.189; 95% confidence interval, 2.118-8.283), followed by low-T3 syndrome (HR, 3.147; 95% CI, 1.558-6.355) and subclinical hypothyroidism (HR, 2.869; 95% CI, 1.817-4.532); subclinical hyperthyroidism did not have a significant impact on mortality. The most common forms of thyroid dysfunction were subclinical hypothyroidism (n = 41, 9%), followed by subclinical hyperthyroidism (n = 35, 7%), low-T3 syndrome (n = 17, 4%), and overt hypothyroidism (n = 12, 3%).

“Monitoring thyroid function is necessary for patients with IDCM, and further study is warranted to investigate whether reversing low thyroid function can benefit these patients,” the investigators noted.

Read the full article here: (J. Clin. Endocrinol. Metab. 2015 [ doi:10.1210/jc.2014-4159 ]).

The investigators reported that they had no financial disclosures to make.