[Substitution with thyroid hormones in the elderly : Goals and risks].

Substitution with thyroid hormones is indicated in elderly patients with overt hypothyroidism, especially, when they present with typical symptoms of hypothyroidism. In light of the current study situation, the use of levothyroxine to treat clinical hypothyroidism in elderly patients is still controversial. In a recent double-blind, randomized, placebo-controlled study, levothyroxine provided no apparent benefits in older persons with subclinical hypothyroidism. The impact of levothyroxine therapy in patients with subclinical hypothyroidism on cardiovascular risk is not completely clear. Levothyroxine treatment is safe and free of side effects, when the thyroid-stimulating hormone (TSH) levels remain within the normal range. Prescription of levothyroxine in patients with only slightly elevated TSH levels often leads to overtreatment, which is associated with an increased risk of fractures, neurological and psychological symptoms, and atrial fibrillation. The recommendations of the European Thyroid Association is to treat elderly patients only when the TSH value is greater than 10 mU/l and the patient is symptomatic or the patient has a high cardiovascular risk. The therapeutic TSH range in elderly patients in the case of levothyroxine treatment should be 1.0-5.0 mU/l. Follow-up of the TSH level is mandatory in order to not oversee a developing overt hypothyroidism and to avoid overtreatment in case of levothyroxine treatment.