Prevalence of thyroid disorders in elderly people in Germany. A screening study in a country with endemic goitre.

Aim: In a screening study on people of working age the prevalence of morphological thyroid disorders was 33.1 %. It is not known precisely whether this further increases after retirement. The present study aimed to establish whether the increase in the prevalence of morphological and functional thyroid disorders continues beyond working age in elderly citizens.
Methods: 223 participants were recruited in an institute for geriatric rehabilitative medicine. All patients were screened by thyroid ultrasound, measurement of serum levels of thyroid hormones and thyroid related autoantibodies as well as measurement of urinary iodine excretion.
Results: The median thyroid volume was 17 ml (range 4-41 ml) in men and 16 ml (range 0.4-73 ml) in women. 27/59 (46 %) of the men (median age [range]: 77 [58-87] years) and 85/139 (61 %) of the women (median age [range]: 77 [52-97] years), or a total of 112/198 (57 %) residents, showed morphological thyroid abnormalities. There was no clear increase with age. 85 % of the participants without a history of thyroid treatment were euthyroid. 12 % showed a subclinical hyperthyroidism whereas 1 % showed a biochemically manifest hyperthyroidism. 2 % were biochemically hypothyroid. Tg-antibodies was elevated in 10 (5 %) and TPO-antibodies in 18 (9 %) of the patients. Median iodine excretion was 129 µg/l. 41.5 % of the patients showed iodine excretion values below 100 µg/l whereas only 7 % of the patients showed a severe iodine deficiency with an excretion below 50 µg/l.
Conclusion: Compared to a previously described population of working age, the prevalence of morphological thyroid disorders does not further increase above the age of 65; thyroid function abnormalities in this iodine sufficient screening population were relatively rare.