Rheumatoid arthritis is an immune attack that reaches far beyond joints
Rheumatoid arthritis is often pictured as sore knuckles in older age. In reality it is the immune system turning on the lining of the joints, most often starting in middle age and hitting women two and a half times as often as men. In up to four in ten patients it spreads to skin, lungs, eyes, heart or blood.
About 17.6 million people worldwide had the disease in 2020, roughly 0.5 to 1 percent of adults in wealthy countries. It caused 38,300 deaths that year, up from 28,000 in 1990. Genes and environment together seem to set it off. The immune assault inflames and thickens the capsule around synovial joints, the fluid-filled kind, and gradually erodes cartilage and bone beneath. Paris physician Augustin Jacob Landre-Beauvais gave the first recognised description in 1800.
Its signature is symmetry and timing. Small joints of the hands and feet are usually hit first, matching on both sides, before larger joints follow. Stiffness is worst after rest and in the morning, sometimes lasting hours, unlike the briefer stiffness of osteoarthritis. That morning pattern may track the body clock: inflammatory messengers such as interleukin-6 rise early in the day. Left unchecked, damage to tendons and joint surfaces can bend fingers into named shapes, such as swan neck, buttonhole and a Z-shaped thumb.
The reach beyond the joints is broad. Firm lumps called rheumatoid nodules appear in about 30 percent of patients, typically over elbows, heels or knuckles. Anaemia is the most common blood change, driven by inflammation that locks iron away. Patients face markedly higher risks of heart attack and stroke, and may not feel typical chest pain. Dry eyes and mouth, lung scarring and carpal tunnel syndrome are recognised complications, and erosion in the upper neck can, in rare untreated cases, compress the spinal cord.
Diagnosis rests on symptoms, with X-rays and lab tests used to support it or rule out look-alikes such as lupus, psoriatic arthritis and fibromyalgia. Treatment aims to cut pain and inflammation and keep people functioning. Disease-modifying drugs such as methotrexate and hydroxychloroquine try to slow progression, biological versions are reserved for stubborn cases, and surgery can repair or replace badly damaged joints.
Source: Rheumatoid arthritis
