*The following is excerpted from an online article posted on National Institutes of Health.
Autoimmunity, a condition in which the body’s immune system reacts with components of its own cells, appears to be increasing in the United States, according to scientists at the National Institutes of Health and their collaborators.
In a study published in Arthritis and Rheumatology, the researchers found that the prevalence of antinuclear antibodies (ANA), the most common biomarker of autoimmunity, was significantly increasing in the United States overall and particularly in certain groups. These groups include males, non-Hispanic whites, adults 50 years and older, and adolescents. The study is the first to evaluate ANA changes over time in a representative sampling of the U.S. population.
The study included 14,211 participants, 12 years and older, in the U.S. National Health and Nutrition Examination Survey (NHANES). The scientists used immunofluorescence, a technique that uses fluorescent dye to visualize antibodies, to examine the frequencies of ANAs in subjects from three time periods. They found that ANA prevalence for 1988-1991 was 11.0%, while for 1999-2004 it was 11.5%, and for 2011-2012 it was 15.9%. These percentages corresponded to 22, 27, and 41 million affected individuals, respectively.
Of the four demographic groups that displayed considerable ANA increases, findings in the adolescent group were the most worrisome to the research team. Young people, ages 12-19, had the largest ANA increases in the study, going from a two-fold to a three-fold increase over the three timeframes.
“The reasons for the increases in ANA are not clear, but they are concerning and may suggest a possible increase in future autoimmune disease,” said corresponding and senior author Frederick Miller, M.D., Ph.D., deputy chief of the Clinical Research Branch at the National Institute of Environmental Health Sciences (NIEHS), part of NIH. “These findings could help us understand more about the causes of these immune abnormalities and possibly learn what drives the development of autoimmune diseases and how to prevent them.”
Source: National Institutes of Health