Psoriasis
Of all the risk factors of psoriatic arthritis, psoriasis is the most relevant and common. Psoriasis is not the same as psoriatic arthritis. Psoriasis affects the skin, not the joints, but it may a precursor of psoriatic arthritis. Around 7.5 million Americans have psoriasis, 30 percent [5] of which go on to develop psoriatic arthritis.
Many people who have psoriatic arthritis develop psoriatic skin lesions up to 10 years before joint symptoms appear. This happens in up to 85 percent [6] of patients. Joint or bone injury if you already have psoriasis may accelerate this. In some people, the joint symptoms precede the skin condition.
A type of psoriasis called nail psoriasis or psoriatic nail dystrophy is the most important early indicator of psoriatic arthritis. It occurs in about 80 percent [7] of patients with psoriatic arthritis.