The Prevalence of Antithyroid Autoantibodies in Normal Korean Population -Age, Sex Distribution and Its Relation to Thyroid Function-

Abstract

The prevalence of antithyroid autoantibodies and the relationship between the presence of autoantibodies and thyroid functions were studied in 848 apparently normal Korean adults with tanned red cell agglutination technique. Results are summarized as follows: 1) The prevalence of antimicrosimal antibody (MCHA) and antithyroglobulin antibody (TGHA) were 4.4% and 1.9% in 458 males, and 12.4% and 5.0% in 390 females, respectively. Both autoantibodies were more prevalent in female (p<0.001, p<0.01). 2) The age-specific prevalence of MCHA was 4.0% in their twenties, 10.1% in their thirties, 12.5% in their forties, 12.0% in their fifties, 8.3% over sixty, and those of TGHA were 2.0% in their twenties, 3.0% in their thirties, 7.0% in their forties, 4.2% in their fifties, 2.5% in subjects over sixty, respectively. Both showed maximal values around forty and fifty and tended to be lower thereafter. 3) Mean T3, T4 and TSH values of high titer group (⩾1:1002) (n=32) were 125 ± 20.6 ng/dl, 9.1 ± 1.7μg/dl and 4.0 ± 1.8 uU/ml, and those of low titer group (<1:1002) (n=44) were 134 ± 24.3 ng/dl, 9.6 ± 1.7 ug/dl and 3.2 ± 1.2 νU/ml. T3 was lower and TSH, higher in high titer group than in low titer group (p<0.05, p<0.05), and no significant difference was observed in T4 level (p<0.1). In conclusion, the prevalence of MCHA and TGHA were higher in apparently normal females than in males with their peaks around forty and fifty, being lower thereafter, and antithyroid autoantibody of high titer (⩾1:1002) was related to alteration of thyroid functions suggesting the existence of “subclinical autoimmune thyroiditis” state.

Positivity rates of antithyroid antibody, antinuclear antibody and thyroid peroxidase antibody in different types of vitiligo

“…Another thyroid‐related autoantibody, Tg Ab, did not differ between NSV and SV. However, the Tg Ab positivity rate was higher in both groups than in the normal Korean population . The Tg Ab positivity rate was significantly higher in the late‐onset than in the early‐onset group.…”

“…This was the only one of the three tested autoantibodies that differed significantly; however, this difference was only just significant ( P = 0.048). The rate of TPO Ab positivity was previously shown to be higher in both types of vitiligo than in the normal population . Additional analyses according to subject characteristics other than the type of vitiligo revealed significantly higher rates of TPO Ab positivity in patients with late‐onset vitiligo and in female patients.…”

“…However, the Tg Ab positivity rate was higher in both groups than in the normal Korean population. 7 The Tg Ab positivity rate was significantly higher in the late-onset than in the early-onset group. Most patients with autoimmune thyroiditis have high serum concentrations of Tg Abs and TPO Abs.…”

“…The rate of TPO Ab positivity was previously shown to be higher in both types of vitiligo than in the normal population. 7 Additional analyses according to subject characteristics other than the type of vitiligo revealed significantly higher rates of TPO Ab positivity in patients with late-onset vitiligo and in female patients. TPO Ab, historically referred to as antimicrosomal antibody, is an antibody against TPO, which has an important role in the formation of thyroid hormones via iodination of tyrosine residues in thyroglobulin.…”

Prevalence of thyroid dysfunction and thyroid autoimmunity in infertile women

“…In a large American survey which for anti-TPO and anti-TG respectively, and women aged 30 to 39 had a prevalence of 12.6% and 13.6% [35] . An earlier Korean study by Lee et al on 390 women, the prevalence of anti-TG was 5% [36] . In a more recent survey, Amouzegar et al measured anti-TPO antibodies in 3390 normal women, and 541 (16%) were found positive [37] .…”