We evaluated 198 subjects between 50 and 85 years of age (older group) and 106 individuals of their offspring in the age group 11-49 years (younger group) in order to determine the frequency of thyroid dysfunction and also identify possible hormonal changes due to aging. The prevalence of thyroid dysfunction was similar in both groups (12.6% in the older and 14.1% in the younger groups). The positivity to one or two anti-thyroid antibodies was also similar between the groups (9.1% and 12.3% for the elderly and the young, respectively), although no correlation with the thyroid dysfunction was found in the elderly. Serum T3 and FT4 levels were significantly lower in the older as compared with the younger subjects (1.27±0.27 vs 1.39±0,31 ng/mL and 0.97±0.29 vs 1.18±0.76 ng/dL, respectively). No statistical significant difference was found between the groups regarding TSH, total T4 and TBG levels. We conclude that the prevalence of thyroid dysfunction was similar between the groups and that the positivity to anti-thyroid antibodies was associated with thyroid dysfunction only in the younger subjects. The inverse correlation between T3 and FT4 levels and the age can reflect an adaptation to the lowest requirements for the hormones with the aging.
Thyroid dysfunction; Prevalence; Aging; Thyroid antibodies; Thyroid hormones
