Age-related changes in thyroid function: a longitudinal study of a community-based cohort
MetadataShow full item record
Context: In cross-sectional studies, serum TSH concentrations increase with age. This has not beenexamined longitudinally, and it is uncertain whether the TSH increase reflects healthy aging oroccult thyroid failure.Methods: We measured serum TSH, free T4, thyroid peroxidase, and thyroglobulin antibodies in1100 participants in the 1981 and 1994 Busselton Health Surveys and derived a reference group of908 individuals without thyroid disease or thyroid antibodies. We examined changes in thyroidfunction longitudinally and, in 781 participants, explored associations with the CAPZB polymorphismrs10917469.Results: At 13 yr follow-up, mean serum TSH increased from 1.49 to 1.81 mU/liter, a change in meanTSH (TSH) of 0.32 mU/liter [95% confidence interval (CI) 0.27, 0.38, P0.001], whereas mean freeT4 concentration was unchanged (16.6 vs. 16.6 pmol/liter, P 0.7). The TSH increase was mostmarked in the elderly, such that gender-adjusted TSH increased by 0.08 mU/liter (95% CI 0.04,0.11) for each decade of baseline age. People with higher baseline TSH values had proportionallysmaller increases in TSH, with each additional 1.0 mU/liter of baseline TSH associated with a 0.13mU/liter decrease (age and gender adjusted) in TSH (95% CI 0.09, 0.16). The TSH did not differsignificantly by CAPZB genotype.Conclusions: Aging is associated with increased serum TSH concentrations, with no change in freeT4 concentrations. The largest TSH increase is in people with the lowest TSH at baseline. Thissuggests that the TSH increase arises from age-related alteration in the TSH set point or reducedTSH bioactivity rather than occult thyroid disease. (J Clin Endocrinol Metab 97: 0000–0000, 2012)
Showing items related by title, author, creator and subject.
Higher free thyroxine levels predict increased incidence of dementia in older men: The health in men studyYeap, B.; Alfonso, Helman; Chubb, S.; Puri, G.; Hankey, G.; Flicker, L.; Almeida, O. (2012)Context: Both hypothyroidism and subclinical hyperthyroidism hinder cognitive function. Objective: We aimed to determine whether more subtle alterations of thyroid hormone levels predict increased incidence of dementia ...
Higher free thyroxine levels are associated with all-cause mortality in euthyroid older men: The Health in Men StudyYeap, B.; Alfonso, Helman; Hankey, G.; Flicker, L.; Golledge, J.; Norman, P.; Chubb, S. (2013)Objective: Thyroid dysfunction predicts poorer health outcomes, but the relationship between thyroid hormone levels within the reference range and mortality in older adults remains unclear. In this study, we examined the ...
Identification of novel genetic loci associated with thyroid peroxidase antibodies and clinical thyroid diseaseO'Leary, Peter (2014)Autoimmune thyroid diseases (AITD) are common, affecting 2-5% of the general population. Individuals with positive thyroid peroxidase antibodies (TPOAbs) have an increased risk of autoimmune hypothyroidism (Hashimoto's ...