Arthritis Res Ther 2021 Apr 9;23(1):108. Epub 2021 Apr 9.
Department of Clinical Neuroscience, Center for Molecular Medicine, Karolinska Institute, Tomtebodavägen 5, 17 177, Stockholm, Sweden.
Background: Hormonal reproductive factors have been suggested to play an important role in the etiology of rheumatoid arthritis (RA), an autoimmune inflammatory disorder affecting primarily women. We conducted a two-sample Mendelian randomization (MR) study examining three relevant exposures, age at menarche (AAM), age at natural menopause (ANM), and age at first birth (AFB) with the risk of RA.
Methods: We collected summary statistics from the hitherto largest GWAS conducted in AAM (N = 329,345), ANM (N = 69,360), AFB (N = 251,151), and RA (N = 14,361, N = 43,923), all of European ancestry. Read More