[The prevalence of thyroid functional disorders in the province of Lleida]

Abstract

Objective: To assess the prevalence of thyroidal disorders in our area using a representative sample of the population in terms of age and distribution by sex.

Design: Descriptive observational transversal study.

Setting: Six areas from the province of Lleida including its capital.

Participants: All the inhabitants older than 6 and living in the region during the time of the study.

Measurements and main results: The study was carried out using a representative sample of the population. Several demographic and clinical parameters that are considered to be related to thyroidal disorders were gathered. A blood sample was performed to measure thyrotropin and thyroidal hormones (total T3, free T3 and free T4) and antithyroidal antibodies. 4 diagnostic categories were defined: overt hypothyroidism, subclinical hypothyroidism, overt hyperthyroidism and subclinical hyperthyroidism. Blood samples from 401 individuals were analyzed. The prevalence of hyperthyroidism has been 5.6% +/- 2.3% of which 4.6% +/- 2.1% corresponds to subclinical hyperthyroidism. The prevalence of hypothyroidism has been 3.48% +/- 1.7% with 1.24% of overt condition and 2.23% of subclinical. We have not found statistical significance by sex in hyperthyroidism while the prevalence of hypothyroidism is significantly higher among women. 42.8% of hypothyroidism showed positive values for antithyroidal antibodies.

Conclusions: The prevalence of thyroidal disorders in the studied area is similar to those other regions with an adequate iodine intake. Hypothyroidism has diminished in the last years. Hyperthyroidism has not changed. Data about prevalence of thyroidal disorders will have increased value in the future if strategies such as screening and treatment of subclinical disorders prove to be beneficial.