Population-based estimates of humoral autoimmunity from the U.S. National Health and Nutrition Examination Surveys, 1960–2014

ObjectiveBased on US National Health and Nutrition Examination Survey (NHANES) data, we attempted to provide an unbiased, population-based estimate of autoantibody prevalence overall and by age and sex.MethodsUS autoantibody prevalence estimates for detectable rheumatoid factor, anti-thyroglobulin, anti-thyroperoxidase, anti-transglutaminase, anti-endomysial, anti-GAD65, antinuclear autoantibodies, and autoantibodies to extractable nuclear antigens were estimated from the 1960–1962 National Health Examination Survey, NHANES III (1988–1994), and the NHANES 1999–2014 cross-sectional surveys. Survey design variables and sample weights were used to account for differential probabilities of selection within the complex survey design. Data analysis used SASTM and SUDAAN™ software. US Census Bureau data were used to estimate the absolute numbers of persons with autoantibodies.ResultsNHANES III data show that the overall US prevalence of having a detectable serum autoantibody is substantial in adults, in both women and men. Thyroid autoantibodies were present in 18% of US adults (31 million persons) including 10% of younger adults and 25% of older persons. Overall autoantibody prevalences increased significantly with age: 32% of US adults 60+ years of age (12.8 million persons) had at least one of the four autoantibodies rheumatoid factor, anti-thyroglobulin, anti-thyroperoxidase, or anti-tissue transglutaminase. Older women had higher levels of autoantibodies, but this was a relative difference. Autoantibody prevalence in both sexes was substantial (women 39%; men 22%). Fourteen percent of adults 60+ years of age have multiple autoantibodies.ConclusionsAutoantibodies are present in a significant fraction of the general population, especially in older adults and women relative to men. Although all known clinically significant autoantibodies were not analyzed, these data provide an important population perspective on the scope and magnitude of humoral autoimmunity in the US. This is vital for prevention efforts to reduce autoimmune disease and helps clarify the potential impact of autoimmunity on the general population.研究目的 基于美国国家健康与营养检查调查（National Health and Nutrition Examination Survey, NHANES）数据，本研究旨在开展无偏倚的人群水平自身抗体患病率评估，涵盖总体人群及按年龄、性别分层的亚组人群。 研究方法 本研究从1960-1962年全国健康检查调查、NHANES Ⅲ（1988-1994年）及1999-2014年NHANES横断面调查数据中，估算了美国可检出的类风湿因子（rheumatoid factor）、抗甲状腺球蛋白抗体（anti-thyroglobulin）、抗甲状腺过氧化物酶抗体（anti-thyroperoxidase）、抗转谷氨酰胺酶抗体（anti-transglutaminase）、抗肌内膜抗体（anti-endomysial）、抗GAD65抗体（anti-GAD65）、抗核自身抗体（antinuclear autoantibodies）及可提取核抗原自身抗体的人群患病率。本研究采用调查设计变量与样本权重，以校正复杂抽样设计中差异化的入选概率；数据分析采用SAS™与SUDAAN™软件完成；同时借助美国人口普查局数据，估算了自身抗体阳性人群的绝对数量。 研究结果 NHANES Ⅲ的数据显示，美国成人总体可检出血清自身抗体的比例较高，男女两性均如此。甲状腺自身抗体在18%的美国成人中检出（约3100万人），其中青年人群占比10%，老年人群占比25%。总体自身抗体患病率随年龄增长显著升高：60岁及以上的美国成人中，32%（约1280万人）至少可检出类风湿因子、抗甲状腺球蛋白抗体、抗甲状腺过氧化物酶抗体或抗组织转谷氨酰胺酶抗体中的1种。老年女性的自身抗体水平更高，但该差异为相对差异。两性的自身抗体患病率均处于较高水平（女性39%，男性22%）。60岁及以上的成人中，14%存在多种自身抗体。 结论 自身抗体广泛存在于普通人群中，尤其在老年人群及女性群体（相较于男性）中检出率更高。尽管本研究未覆盖所有已知具有临床意义的自身抗体，但上述数据为阐明美国体液自身免疫的范围与规模提供了重要的人群视角。该结果对于自身免疫病的防控工作至关重要，同时有助于明确自身免疫对普通人群的潜在影响。