To the Editor:
We read with interest the article by Berens, et al1 reporting that increasing age was associated with positivity for anticyclic citrullinated peptide antibodies (anti-CCP) 3.1 and anti-CCP–IgA in individuals at risk of rheumatoid arthritis (RA), that is, first-degree relatives (FDR) of patients with RA. We found similar results in a Swiss cohort of FDR: anticitrullinated protein antibodies (ACPA) positivity, particularly anti-CCP3.1, was associated with older age2. However, in contrast to Berens, et al1, we found a peak in prevalence in the age group of 45 to 55 …
Address correspondence to Dr. D. Alpizar-Rodriguez, Geneva University Hospital, 26 Ave. Beau-Séjour, 1211 Geneva, Switzerland. E-mail: deshire_alpizar{at}hotmail.com, Axel.Finckh{at}hcuge.ch