Fibromyalgia was found to contribute to a poorer perceived quality of life (QoL) related to physical function in patients with undifferentiated connective tissue diseases (UCTDs). Overall, patients with UCTDs perceived both their physical and mental health as inferior compared to how the general population perceived it. The study, “Longitudinal analysis of quality of life in patients with undifferentiated connective tissue diseases,” was published in the journal Patient Related Outcome Measures. UCTDs are autoimmune diseases in which the body damages its own tissues, resulting in the injury of major organs. Chronic autoimmune diseases are often accompanied by fibromyalgia, a disorder characterized by chronic widespread pain. The study followed 46 patients (95.6% were female) with UCTDs, 16 of whom also had fibromyalgia. Participants filled out the Short-Form 36 (SF-36) Health Survey questionnaire at the beginning of the study and one and two years later. The majority of the UCTD patients scored lower on the physical component summary (PCS) — related to physical well-being — and mental component summary (MCS) — related to mental well-being — than did the general population, both at the beginning and at the end of the study. While about one-third of the patients with UCTD patients improved their scores over the course of the study, only 26% reached levels higher than the average seen in the general population for the PCS, and 13% for the MCS. Fibromyalgia was found to have a negative impact on PCS scores, indicating a worse perceived QoL related to physical problems among patients with UCTDs and fibromyalgia, compared to those without fibromyalgia. Having fibromyalgia did not appear to influence MCS scores in patients with UCTDs.