Arthritis is a group of conditions involving damage or inflammation to joints of the body. It is very painful as joints move body parts connected by bones and inflammation can limit mobility by causing swelling, pain and heat. Uncontrolled inflammation can also lead to increased levels of C-reactive protein, an independent risk factor for heart disease.
There are many types of arthritis (over 100 and growing) each with different causes. All types of arthritis feature pain, which may differ depending on the type and the location. Rheumatoid arthritis is generally worse in the morning and associated with stiffness; in the early stages, patients often have no symptoms after a morning shower.