Syndrome de basse T3 chez des patients âgés présentant une dénutrition modérée ou sévère

Under nutrition causes alterations in serum thyroid function tests referred as “non-thyroidal illness syndrome” (NTIS). We determined serum thyroid hormones in elderly patients (≥ 70 years) with mild (25 ≤ albuminemia < 35 g/l, N = 64) or severe (albuminemia < 25 g/l, N = 67) under nutrition, compared to well-nourished patients (albuminemia ≥ 35 g/l, N = 78). Patients with under nutrition had lower (32%) free T3 (FT3) and higher (21%) free T4 (FT4) concentrations than in controls. TSH level was similar in the three groups of patients. Therefore, malnourished elderly patients showed euthyroidism profile, whatever the severity of under nutrition. The decrease in FT3 level was more marked in patients with severe under nutrition. In addition, there was a positive correlation between FT3 and albumin, transthyretin and transferrin and a negative correlation with PINI (“prognostic inflammatory and nutritional index”). These data showed that FT3 is a good marker of severity of under nutrition in elderly patients.