Fibromyalgia As A Disease Associated With The Human T Cell Lymphotropic Virus Type I (HTLV-I) Infection

Background: Rheumatic diseases as Rheumatoid Arthritis and Sjoegren's Syndrome are reported in HTLV-I infected individuals, but there are no studies about the prevalence of fibromyalgia in those patients. Methods: A case-control study with prevalent cases was carried out. Ex-blood donation candidates with HTLV-I infection, followed in a cohort from a brazilian blood bank and blood donors without the virus infection were submitted to a rheumatologic evaluation to compare the prevalence of fibromyalgia. Age, sex, personal income, years of study, depression and other rheumatic diseases were evaluated as co-variables. Results: One hundred individuals with HTLV-I infection and 62 blood donors without infection were studied. Thirty-eight (38%) HTLV-I infected individuals and three (4.8%) individuals from the control group presented the diagnosis of fibromyalgia (OR [95%IC] = 12.05 [3.53-41.17]). Other rheumatic diseases were also more prevalent in the infected group (37% vs. 12.9%; OR [95%IC] = 3.80 [1.63-8.86]). In the multivariate analysis adjusted by the co-variables, the association between HTLV-I and fibromyalgia kept statistical significance (OR [95%IC] = 9.14 [2.42-34.52]). Conclusions: This study shows a greater prevalence of fibromyalgia in HTLV-I infected individuals, suggesting that fibromyalgia may be a clinical condition associated with this viral infection.