The aging thyroid

As life expectancy increases and population age advances, diagnosis and treatment of diseases common in the geriatric population assume an increasingly important role in modern medicine. In the last few years, the emergence of age-specific reference ranges for thyroid-stimulating hormone (TSH) has added to the complexity of diagnosis of thyroid dysfunction in this age group, especially in the 'subclinical' category.

The recent studies confirm an increase in population TSH distribution with age, both in cross-sectional and longitudinal studies. Conclusive evidence about adverse cardiovascular, metabolic, and cognitive consequences of subclinical hypothyroidism in the elderly remains elusive. The transient nature of subtle degrees of thyroid dysfunction in a significant proportion of elderly patients has also been reproduced in the recent publications.

A growing body of literature in the last few years, reviewed here, highlights the importance of employing additional caution before assigning diagnoses of hypothyroidism or hyperthyroidism to elderly patients and initiation of treatment modalities that can have long-lasting effects.