The correlation study of autoimmunity antinuclear antibody and aging / 中华老年医学杂志

ABSTRACT

Objective To investigate the influences of age and sex on the expression of serum antinuclear antibody (ANA) and its titer level.Methods The serum ANA in 993 people aged 60 years and over were detected and titer of positive serum were analyzed. They were divided into different groups according to age and sex. Two hundred healthy cases aged less than 60 years were collected as control group. Results The serum ANA positive rate was increased with age and it was significantly higher in people aged 60 years and over than aged less than 60 years (29. 1% vs. 14.0%, x2=5. 074, P=0. 025). The serum ANA positive rates were 24.1%, 30. 5% and 33.6% in people aged 60-69 group, aged 70-79 group and aged above 80 group. Among people aged 60 years and over, the positive rate was 35.8% in female group, which was higher than in male group (22. 4%) (x2= 21. 179, P=0. 05). The titre levels of the positive samples were increased with age. In control group, the samples with 1 100 titre was 57.1% among the positive samples, which was higher than in the elderly group (36. 3%). And in control group, the samples with 1 3200 titre was 0 among the positive samples, which was lower than in the elderly people group (7.6%). The ANA preliminary screening in people aged 60 years and over showed that the titre level was less than 1 320-1 1000 in female and less than 1 100-1 320 in male. Its specificity could be up to about 90%. Conclusions The serum ANA positive rate in people aged 60 years and over is affected by age and sex. The positive rate is higher in female than in male and it is increased with age. It suggests that 1 320 to 1 1000 could be taken as ANA preliminary screening critical value in female and 1 100 to 1 320 in male.