抄録
The prevalence of subclinical autoimmune thyroid diseases (AITD) was investigated with determinations of highly sensitive anti-thyroid peroxidase antibody (TPOAb), anti-thyroglobulin antibody (TgAb) and thyroid stimulating hormone (TSH) in serum samples obtained from 2,647 ostensibly healthy subjects (1,887 males and 760 females, aged 46.0±10.4 years, Mean±SD) residing in Sapporo who were recruited at the hospital for medical examinations. The prevalence of thyroid autoantibodies (TAA) was 9.1% (n=242), among which 23.6% was TgAb positive only (>1.83 U/ml), while 46.3% was TPOAb positive only (>0.34 U/ml), and the remaining 32.2% were both TPOAb and TgAb positive. TAA was positive in 6.5% for males and 15.8% for females (P<0.001) with an age-related increase. The prevalence of subclinical hyperthyroidism (TSH<0.15 mU/L) was 0.79%, of which 42.1% was positive for TAA. The prevalence of subclinical hypothyroidism (TSH>5.0 mU/L) was 1.1%, of which 20% were TAA positive. The overall prevalence of subclinical autoimmune thyroiditis as defined by TAA positive eu- and hypothyroidism was 8.8%; 6.3% for males and 15.5% for females (P<0.001). There was a significant inverse correlation between TPOAb and TSH levels (r=-0.21, P<0.05, n=112) in subjects with TPOAb positive only and also a significant correlation between TgAb and TSH levels in subjects with positive TgAb with or without TPOAb (r=0.27, P<0.01, n=130). This study indicates that the combined analysis of TPOAb, TgAb and TSH may provide more accurate information on the prevalence of AITD in the population study.
