Effects of environmental factors and omega-3 fatty acids on rheumatoid arthritis

With a prevalence that has been estimated to be 0.5%±0.2% and a female predominance, rheumatoid arthritis (RA) represents the most common chronic systemic autoimmune rheumatism. Typically, RA is characterized by polyarticular pain, morning stiffness, fatigue, joint and bone inflammation and destruction (1). A more severe evolution is encountered in RA patients with an age lower than 50 years at diagnosis, anti-cyclic citrullinated peptides (anti-CCP) autoantibody (Ab) positivity, IgM rheumatoid factor (RF) at elevated levels (>50 UI/mL), and bone erosions (2,3). RA appears to present geographical variations with an apparent reduction from north to the south, and from urban to rural areas (4).