[Problems in the diagnosis of thyroid dysfunction of the elderly adult]

Thyroid disfunction in the aged is often misdiagnosed either due to scanty symptoms, masking by other ailments or because function tests can be altered by extrathyroid causes such as chronic diseases, drugs or undernutrition. We surveyed 93 patients from 60 to 104 years old (73 females) living in geriatric homes. Most received at least 2 drugs for control of hypertension, coronary artery disease, diabetes, parkinsonism or psycho-organic deterioration. No clinical evidence of thyroid disfunction was found in 75 patients. T3 was 73.6 +/- 25.5 ng/dl, T4 7.3 +/- 1.8 micrograms/dl, TSH 2.8 +/- 0.9 uU/ml and rT3 32.2 +/- 16.3 ng/dl. Antimicrosomal antibodies were negative in all. Significant differences were found comparing these values with those obtained in 26 normal adults with mean age 39.9 years: T3 was lower and TSH and rT3 were higher in the elderly (p less than 0.0001). T3 decreased and rT3 increased in relation to age and males had significantly lower values of T3, T4 and TSH than females. Some evidence of thyroid disfunction was present in the remaining 18 patients: 9 had multinodular and/or positive antimicrosomal antibodies with euthyroid hormone levels; 6 had elevated T3, T4 and fT4 so hyperthyroidism was suspected; the remaining 3 patients had TSH levels above 20 uU/ml indicating the presence of hypothyroidism of which only one had some clinical manifestation. Thus, thyroid disfunction in the elderly + is not uncommon (3.2% of hyperthyroidism and 2.6% hypothyroidism in this series) in the absence of clinical manifestation. Treatment may improve the quality of life in these patients.