In a study, Australian researchers investigated whether biochemical markers of thyroid disorders are associated with prevalent depression and incident clinically significant depression.
Their findings were published in the September 2011 edition of American Journal of Geriatric Psychiatry in the article “Thyroid hormones and depression: the health in men study.”
The research team used cross-sectional and cohort studies to analyze patients from a community-dwelling sample. Included in this study were 3,932 men (69 to 87 years old).
Study participants did not have overt thyroid disease.
The 15-item Geriatric Depression Scale was used to determine the presence of prevalent clinically significant depression, and the Western Australia Data Linkage System was used to establish the onset of depression according to the International Classification of Diseases.
Results showed that the serum concentration of thyroid-stimulating hormone and free thyroxine did not impact the odds of prevalent depression or risk of incident depression.
Odds of prevalent depression were 0.8 (95% confidence interval [CI]=0.5 to 1.3) for men who had subclinical hypothyroidism and 1.4 (95% CI=0.3 to 5.8) for study participants who had subclinical hyperthyroidism. Hazard ratio of incident depression linked with subclinical hypothyroidism was 0.7 (95% CI=0.3 to 1.9).
Researchers noted that no men with subclinical hyperthyroidism developed depression during the follow-up period of 5.5±1.4 years.
They concluded that subclinical thyroid disease is not associated with prevalent depression or incident depression in older men and that these findings do not support routine screening of subclinical thyroid disorders in older adults who have depression.