[Preclinical hypothyroidism: early involvement of memory function, behavioral responsiveness and myocardial contractility].

Subclinical hypothyroidism in characterized by elevated TSH levels in the face of normal thyroid hormone concentrations. The purpose of this study was to evaluate whether these subjects show alterations of neuropsychological and behavioural features and of myocardial contractility as patients with overt hypothyroidism do. We evaluated in 14 subjects the hormonal profile (total and free T3 and T4, TSH), memory ability (Wechsler Memory Scale), behavioural reactivity (Crown & Crisp Experimental Index) and the pre-ejection period (isometric systole). We found an evident impairment of some cognitive functions correlated to memory and a behavioural alteration, perhaps secondary to the disease state, and moreover an early defect of myocardial contractility, represented by prolonged pre-ejection period. These results suggest that these patients should be treated with adequate doses of L-Thyroxine, like in overt hypothyroidism.