Influence of serum levels of thyroid-stimulating hormone and anti-thyroid peroxidase antibodies, age and gender on depression as measured by the Zung Self-Rating Depression Scale.

Abstract

The AIM of the present study was to explore the level of depression in the respondents using the Zung self-rating depression scale (SDS) and find a correlation with the levels of the thyroid-stimulating hormone (TSH) and the anti-thyroid peroxidase antibodies (anti-TPO), the age and gender of the participants. 2401 subjects aged 20-84 yrs were included, 1344 of them female aged 48.7 +/- 14.4 yrs and 1057 male, aged 46.5 +/- 14.5 yrs (p < 0.001). All participants completed the Zung SDS questionnaire and a depressive score was calculated and interpreted as follows: less than 49 points--no depression, between 50 and 59 points--mild depression, between 60 and 69 points--moderate depression and more than 69 points-- severe depression. Body height and weight were measured and serum TSH and Anti-TPO were determined. SDS was higher in the females (47.6 +/- 9.7 vs. 41.7 +/- 8.6, p < 0.001) and correlated with the subjects' age (Spearman's rho(female) = 0.447, p < 0.001, P(male) = 0.402, p < 0.001). Depression was more prevalent in the females (all p < 0.001) with hypothyroidism than in the euthyroid subjects (odds ratio 1.8, 95% CI 1.15-2.80, p < 0.011). The odds ratio for depression was 3.47 (2.64-4.57) for the female gender and the risk of depression increased by 6% (5 - 7) with each added year of age. The anti-TPO, BMI and waist circumference did not influence the regression models. The depressive score was higher in the females and increased with age. Hypothyroidism determined a higher risk of depression in the females.