A Toolbox for Personalized Medicine of Methotrexate Therapy in Arthritis

Abstract

Rheumatoid arthritis (RA) is a chronic autoimmune disease. It is characterized by swelling and pain of the joints, uncontrolled proliferation of synovial tissue and multisystem co-morbidities like cardiovascular disease and thyroid disease. RA mainly affects the joints of the extremities like hands, feet, knees, wrist and elbows. Joint damage can occur early in the disease course when the disease is not treated effectively. More than 21% of United states adults (46.4 million persons) were found to have self-reported physician diagnosed arthritis. The specific diagnose of RA has a prevalence of 1%. The prevalence of RA among women is approximately double that in men. There is still no cure for RA, despite the fact that treatment strategy has changed considerably over the years. Early initiation of therapy is effective in prevention of joint damage and results in milder medication regimens while maintaining disease remission. Early in the disease, inflammation is less self-perpetuating and easier to suppress, therefore it is important to start treatment as early as possible in order to optimize outcome, minimize medical costs, improve quality of life, and improve medical decision making. For RA, a prediction model has been developed that divides patients into 3 groups according to their likelihood of progressing to persistent arthritis. Juvenile idiopathic arthritis (JIA) is one of the most common autoimmune diseases in childhood with a reported prevalence between 16 and 150 per 100.000.7 JIA is a heterogeneous disease, characterized by chronic inflammation of one or more joints, which begins before age of 16, persists for more than 6 weeks and is of unknown origin. It encompasses various subtypes, defined by the International League of Associations for Rheumatology (ILAR) criteria, whose severity and clinical course differ.8,9 Although heterogeneous, the common denominator in JIA is chronic arthritis, which can lead to joint destruction and long-term disabilities.This puts a heavy toll on children, their parents and society. Such serious consequences in both RA and JIA put the aim of attaining tight disease control in these arthritic diseases to the forefront.