Endocrine Abstracts

It has been demonstrated that hypothryoidism could affect the prognosis of patients with cardiovascular disease. The aim of this study was to better clarify the prognostic role of hypothyroidism in patients with chronic heart failure (CHF).

We enrolled 384 consecutive outpatients (65±13 years, 296 males, NYHA 2.3±0.6, left ventricular ejection fraction, LVEF, 32±9%) with CHF (ESC criteria), in stable clinical conditions (at least 30 days) and in conventional therapy (at least 6 months) (91% ACE-inhibitors and/or AT1R antagonists, 89% betablockers, 87% diuretics, 54% aldosterone antagonists). The presence of hypothyroidism was defined according to a previous diagnosis of hypothyroidism or to its diagnosis at the enrolment or during follow-up. Overt hypothyroid patients and patients with subclinical hypothyroidism and a TSH ≥10 mU/l were always treated with levothyroxine, aiming to have a TSH in the normal reference range. Patients with a TSH slightly above the normal range but <10 mU/l were either treated or simply revaluated over the time. Patients with hyperthyroidism were excluded.

In 91 (24%) patients of study population hypothyroidism was detected. During follow-up (31±10 months), a total of 98 patients were hospidalized for acute decompensated heart failure (ADHF) and 58 died. A diagnosis of hypothyroidism was significantly associated to ADHF occurrence at univariate (HR: 2.17; 95% CI: 1.44–3.27; P<0.001) as well as at multivariate Cox regression analysis (HR: 1.58; 95% CI: 1.02–2.45) after correcting for age, presence of ischemic cardiomyopathy, arterial systolic pressure, NYHA class, LVEF and levels of creatinine, Sodium and NT-proBNP. No association was found, however, between diagnosis of hypothyroidism and mortality (HR: 1.15; 95% CI: 0.639–2.07; P: NS). Fig. shows Kaplan Meier curves for events in patients with and without a diagnosis of hypothyroidism.

In conclusion, in CHF outpatients the diagnosis of hypothyroidism is independently associated to a greater probability of ADHF occurrence but not of mortality.

Figure 1