title: Tuberculosis incidence in a cohort of individuals infected with human T-lymphotropic virus type 1 (HTLV-1) in Salvador, Brazil.
abstract: Few reports have investigated the association between human T-lymphotropic virus type 1 (HTLV-1) and tuberculosis (TB) in countries where both infections are endemic. This study estimates the incidence of TB in a cohort infected with HTLV-1, compared with non-infected individuals, over a ten-year period.
  
  
  
  Retrospective cohort study involving the cross-matching of records of individuals for whom a HTLV serology was performed at a referral center for HTLV (CHTLV) with a database of TB cases from Sinan-the Information System on Diseases of Compulsory Declaration between 2002 and 2012.
  
  
  
  From a cohort of 6,495 individuals, 1,711 were infected with HTLV-1. A total of 73 TB cases occurred during the study period: 33 HTLV-1-infected patients and 40 uninfected individuals. The incidence density for TB in the HTLV-1 infected group was 3.3 person-years per 1,000 individuals and 1.1 person-years per 1,000 individuals in the group HTLV-1 uninfected group. The relative risk of developing TB in the group of patients infected with HTLV-1 was 2.6 (CI 95 % 1.6-4.2) in comparison with HTLV-1 uninfected group. Compared to individuals with isolated TB, those in the HTLV-1 infected group who had TB were older (p = 0.005) and had lower education levels (p = 0.02). No differences were observed with respect to the clinical/radiological presentation, nor in the outcome of TB and prevalence of HIV infection, when comparing among the HTLV-1-infected and uninfected groups.
  
  
  
  Patients infected with HTLV-1 are more susceptible to TB. The epidemiological characteristics of HTLV-1/TB subjects and those infected with TB overlap.
authors.affiliation: Laboratório Avançado de Saúde Pública, Fundação Oswaldo Cruz-Bahia (FIOCRUZ), Rua Waldemar Falcão, 121, Candeal, CEP: 40296-710, Salvador, Bahia, Brazil. grassi@bahia.fiocruz.br.|Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil. grassi@bahia.fiocruz.br.
authors.forename: Maria Fernanda Rios
authors.initials: MF
authors.lastname: Grassi
authors.affiliation: Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil.
authors.forename: Normeide Pedreira
authors.initials: NP
authors.lastname: Dos Santos
authors.affiliation: Hospital Universitário professor Edgar Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Monique
authors.initials: M
authors.lastname: Lírio
authors.affiliation: Programa Acadêmico de Tuberculose, Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Afrânio Lineu
authors.initials: AL
authors.lastname: Kritski
authors.affiliation: Laboratório de Epidemiologia, Fundação Oswaldo Cruz- Bahia, Salvador, Bahia, Brazil.
authors.forename: Maria da Conceição
authors.initials: Mda C
authors.lastname: Chagas Almeida
authors.affiliation: Laboratório Avançado de Saúde Pública, Fundação Oswaldo Cruz-Bahia (FIOCRUZ), Rua Waldemar Falcão, 121, Candeal, CEP: 40296-710, Salvador, Bahia, Brazil.|Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil.
authors.forename: Leonardo Pereira
authors.initials: LP
authors.lastname: Santana
authors.affiliation: Laboratório Avançado de Saúde Pública, Fundação Oswaldo Cruz-Bahia (FIOCRUZ), Rua Waldemar Falcão, 121, Candeal, CEP: 40296-710, Salvador, Bahia, Brazil.|Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil.
authors.forename: Noilson
authors.initials: N
authors.lastname: Lázaro
authors.affiliation: Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil.|Departamento de Vigilância Epidemiológica, Secretaria da Saúde do Estado da Bahia, Salvador, Bahia, Brazil.
authors.forename: Juarez
authors.initials: J
authors.lastname: Dias
authors.affiliation: Hospital Universitário professor Edgar Santos, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: Eduardo Martins
authors.initials: EM
authors.lastname: Netto
authors.affiliation: Laboratório Avançado de Saúde Pública, Fundação Oswaldo Cruz-Bahia (FIOCRUZ), Rua Waldemar Falcão, 121, Candeal, CEP: 40296-710, Salvador, Bahia, Brazil.|Escola Bahiana de Medicina e Saúde Pública, Salvador, Bahia, Brazil.
authors.forename: Bernardo
authors.initials: B
authors.lastname: Galvão-Castro
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D015490:HTLV-I Infections / Q000150:complications* / Q000821:virology; D015368:Human T-lymphotropic virus 1 / Q000302:isolation & purification; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D014397:Tuberculosis, Pulmonary / Q000150:complications / Q000453:epidemiology*; D055815:Young Adult
keywords: HTLV-1; Human T-lymphotropic virus type 1; Incidence; Relative risk; Tuberculosis