PREVALENCE OF AUTOIMMUNE THYROIDITIS AND THYROID DYSFUNCTION IN HEALTHY ADULT MEXICANS WITH A SLIGHTLY EXCESSIVE IODINE INTAKE.
OBJECTIVE
the purpose of this study was to evaluate the prevalence of autoimmune thyroiditis and thyroid dysfunction in healthy individuals with no previously known thyroid disease, in an urban area of Mexico City.


METHODS
the study was conducted on volunteers with no known thyroid disease. We recruited 427 subjects among the hospital's medical and administration personnel. All underwent thyroid ultrasound (US) and TSH, free T4 (FT4), total T3 (TT3), thyroid anti-peroxidase (TPOAb) and anti-thyroglobulin (TgAb) antibodies were measured. Hypoechogenicity and thyroid volume were determined by US. Urinary iodine (UI) excretion was also measured.


RESULTS
the frequency of autoimmune thyroiditis was 8.4% (36/427) and women were most commonly affected than men (11.6 vs. 4.3% respectively, P = 0.008); when including cases of atrophic thyroid, the frequency increased to 15.7% (67/427). Clinical hypothyroidism was detected in 1.2% (5/427) and it was sub-clinical in 5.6% of individuals. A goiter was present in 5.9% (25/427) of volunteers. Median UI was 267 μg/L, (IQR 161.3 - 482.5).


CONCLUSIONS
in spite of our study's limitations, the frequency of autoimmune thyroiditis is clearly elevated in the studied population. Further studies are necessary in order to define the prevalence of autoimmune thyroid disease as well as the current iodine nutritional status in our country.
Department of Internal Medicine, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán".. afcalatrava@yahoo.com.
Armando
A
Flores-Rebollar
Department of Internal Medicine, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán".. lidiamorenoc@gmail.com.
Lidia
L
Moreno-Castañeda
Department of Internal Medicine, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán".. nsaid_vega86@hotmail.com.
Norman S
NS
Vega-Servín
Department of Endocrinology, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán",. guloca@hotmail.com.
Guadalupe
G
López-Carrasco
Department of Nuclear Medicine, Instituto Nacional de Ciencias Médicas y Nutrición "Salvador Zubirán", México.. seguridad_radiologica@hotmail.com.
Aída
A
Ruiz-Juvera
D000293:Adolescent; D000328:Adult; D000368:Aged; D015415:Biomarkers; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000453:epidemiology / Q000503:physiopathology; D007037:Hypothyroidism / Q000453:epidemiology / Q000503:physiopathology; D007455:Iodine / Q000008:administration & dosage*; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D011159:Population Surveillance; D015995:Prevalence; D013960:Thyroid Function Tests; D013967:Thyroiditis, Autoimmune / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology*; D014505:Urban Population; D055815:Young Adult
D015415:Biomarkers; D007455:Iodine