title: A nested case-control study of risk factors for adult T-cell leukemia/lymphoma among human T-cell lymphotropic virus type-I carriers in Japan.
abstract: OBJECTIVE
  The purpose of this study was to investigate the serological risk factors for development of adult T-cell leukemia/lymphoma (ATL) among human T-cell lymphotropic virus type-I (HTLV-I) carriers.
  
  
  METHODS
  A nested case-control study was performed. The source population comprised 23,922 subjects who had either visited the outpatient clinic or who had received annual health check-ups at the K Hospital, Nagasaki, Japan, at least once during 1985-1996 (HTLV-I seroprevalence = 16.1%). Markers of HTLV-I infection were examined in stored sera from 29 incident cases of ATL diagnosed during 1985-1997, and 158 controls matched for sex, birth year, date of sample collection, and HTLV-I seropositivity (median follow-up = 6.4 years).
  
  
  RESULTS
  In exact conditional logistic regression analysis, high levels of soluble interleukin-2 receptor (> or = 500 U/ml) and high HTLV-I antibody titers (> or = 1,024) were independently associated with an increased risk of developing ATL (Odds ratio 20.5. 95% confidence interval (CI) 4.5-194 and 2.9, 95% CI 0.98-9.5, respectively). The results remained essentially unchanged when the subjects were restricted to those whose histories were followed for two years or longer.
  
  
  CONCLUSIONS
  These findings indicate that high soluble interleukin-2 receptor levels and high HTLV-I antibody titers are strong predictors of ATL among carriers of HTLV-I.
authors.affiliation: Department of Preventive Medicine and Health Promotion, Nagasaki University School of Medicine, Japan. k-iwata@net.nagasaki-u.ac.jp
authors.forename: Kokichi
authors.initials: K
authors.lastname: Arisaw
authors.forename: Shigeru
authors.initials: S
authors.lastname: Katamine
authors.forename: Shimeru
authors.initials: S
authors.lastname: Kamihira
authors.forename: Kenji
authors.initials: K
authors.lastname: Kurokawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Sawada
authors.forename: Midori
authors.initials: M
authors.lastname: Soda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Doi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Saito
authors.forename: Satoshi
authors.initials: S
authors.lastname: Shirahama
mesh_terms: D017677:Age Distribution; D002353:Carrier State; D016022:Case-Control Studies; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D015481:HTLV-I Antibodies / Q000032:analysis; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification*; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000175:diagnosis / Q000453:epidemiology*; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D011336:Probability; D011379:Prognosis; D012016:Reference Values; D018570:Risk Assessment; D012307:Risk Factors; D017678:Sex Distribution; D016019:Survival Analysis
chemical_list: D015481:HTLV-I Antibodies