Depression symptoms and hypothyroidism in a population-based study of middle-aged Brazilian women

Overt hypothyroidism is often recognized as an important cause of depression, but in sub-clinical cases, results are inconsistent and most prior studies have involved small samples.

We evaluated the association between hypothyroidism and depressive symptoms (PRIME-MD) in a population-based study of 1298 middle-aged women living in a large metropolitan city in Brazil.

45.7% presented depressive symptoms, and 12.3% presented hypothyroidism. Multiple logistic regression analysis adjusting for age, race, smoking and body mass index showed that women with TSH>10 mUI/ml had a threefold chance of presenting depressive symptoms compared to those with normal levels of TSH. Among those with clinical hypothyroidism the adjusted OR was 8.7.

High levels of TSH were associated to an increased chance of developing depression in the general population. Therefore, depressive symptoms must be considered in patients with thyroid dysfunction and depressed patients should be tested for TSH.