title: Vitamin A and risk of HIV-1 seroconversion among Kenyan men with genital ulcers.
abstract: BACKGROUND
  Vitamin A is involved in normal immune function and the maintenance of mucosal integrity through complex effects on cellular differentiation.
  
  
  OBJECTIVE
  We sought to determine whether serum vitamin A levels were associated with altered susceptibility to primary infection with HIV-1 in men with high-risk sexual behaviour and genital ulcers who presented for treatment at an STD clinic in Nairobi, Kenya.
  
  
  METHODS
  HIV-1 seronegative men were prospectively followed. Vitamin A levels at study entry were compared among 38 men who HIV-1 seroconverted versus 94 controls who remained HIV seronegative.
  
  
  RESULTS
  Vitamin A deficiency (retinol less than 20 microg/dl) was very common and was present in 50% of HIV-1 seroconverters versus 76% of persistent seronegatives. Seroconversion was independently associated with a retinol level greater than 20 microg/dl (HR 2.43, 95% CI 1.25-4.70, P = 0.009), and a genital ulcer aetiology caused by Haemophilus ducreyi (HR 3.49, 95% CI 1.03-11.67, P = 0.04). Circumcision was independently associated with protection (HR 0.46, 95% CI 0.23-0.93, P = 0.03).
  
  
  CONCLUSIONS
  Vitamin A deficiency was not associated with an increased risk of HIV-1 infection among men with concurrent STD. A decreased risk of HIV-1 seroconversion was independently associated with lower retinol levels. The effects of vitamin A on macrophage and lymphoid cell differentiation may paradoxically increase mucosal susceptibility to HIV-1 in some vulnerable individuals, such as men with genital ulcers. Lack of circumcision and chancroid are confirmed as important co-factors for heterosexual HIV-1 transmission. The role of vitamin A in heterosexual HIV-1 transmission requires further study.
authors.affiliation: Department of Microbiology, Mount Sinai Hospital, Toronto, Canada. kmacdonald@mtsinai.on.ca
authors.forename: K S
authors.initials: KS
authors.lastname: MacDonald
authors.forename: I
authors.initials: I
authors.lastname: Malonza
authors.forename: D K
authors.initials: DK
authors.lastname: Chen
authors.forename: N J
authors.initials: NJ
authors.lastname: Nagelkerke
authors.forename: J M
authors.initials: JM
authors.lastname: Nasio
authors.forename: J
authors.initials: J
authors.lastname: Ndinya-Achola
authors.forename: J J
authors.initials: JJ
authors.lastname: Bwayo
authors.forename: D S
authors.initials: DS
authors.lastname: Sitar
authors.forename: F Y
authors.initials: FY
authors.lastname: Aoki
authors.forename: F A
authors.initials: FA
authors.lastname: Plummer
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D002602:Chancroid / Q000150:complications; D005832:Genital Diseases, Male / Q000150:complications*; D006679:HIV Seropositivity / Q000097:blood / Q000150:complications / Q000503:physiopathology*; D015497:HIV-1; D006801:Humans; D007630:Kenya; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D012307:Risk Factors; D013587:Syphilis / Q000150:complications; D014456:Ulcer / Q000150:complications*; D014801:Vitamin A / Q000097:blood; D014802:Vitamin A Deficiency
chemical_list: D014801:Vitamin A