title: High prevalence of arthropathy in HTLV-I carriers on a Japanese island.
abstract: OBJECTIVE
  To determine the aetiological relationship between human T cell leukaemia virus type-I (HTLV-I) and arthritis, by performing an epidemiological study of the inhabitants of Tsushima, an island northwest of the main island of Kyushu, Japan, which is an endemic area of HTLV-I.
  
  
  METHODS
  A total of 7087 people underwent an annual health check, and those with arthropathy had further physical and radiological examinations by rheumatologists. The presence of HTLV-I antibody was determined by the particle agglutinin method, and integration of the proviral DNA in peripheral lymphocytes was confirmed by polymerase chain reaction.
  
  
  RESULTS
  HTLV-I was positive in 26.1% of inhabitants; the incidence increased to 37.0% in patients with symptoms of polyarthritis. The prevalence of rheumatoid arthritis (RA) was significantly different between HTLV-I carriers (0.56%) and non-carriers (0.31%). The stage of bone destruction in HTLV-I carriers with articular symptoms was milder than that in RA patients without HTLV-I. The relative risk of HTLV-I infection for polyarthritis was 1.66 (p < 0.05).
  
  
  CONCLUSIONS
  This is the first epidemiological report clarifying the association between HTLV-I and polyarthritis. Our results suggest that this viral infection has a relationship to RA.
authors.affiliation: Department of Orthopaedics, Nagasaki Chuo National Hospital, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Motokawa
authors.forename: T
authors.initials: T
authors.lastname: Hasunuma
authors.forename: K
authors.initials: K
authors.lastname: Tajima
authors.forename: A M
authors.initials: AM
authors.lastname: Krieg
authors.forename: S
authors.initials: S
authors.lastname: Ito
authors.forename: K
authors.initials: K
authors.lastname: Iwasaki
authors.forename: K
authors.initials: K
authors.lastname: Nishioka
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D001172:Arthritis, Rheumatoid / Q000453:epidemiology / Q000821:virology*; D002353:Carrier State; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D015490:HTLV-I Infections / Q000150:complications* / Q000235:genetics / Q000276:immunology; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012306:Risk
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral