It varies depending on the study and the cohort you are looking at. When you look at all studies that try to assess the presence of fibromyalgia in patients with various rheumatic diseases, it ranges ...

Nov. 6, 2025 -- Fibromyalgia affects about 4 million U.S. adults. Though its cause remains unclear, it can be effectively diagnosed, treated, and managed. But what exactly is fibromyalgia, and why is ...