title: Using age-specific mortality of HIV infected persons to predict anti-retroviral treatment need: a comparative analysis of data from five African population-based cohort studies.
abstract: OBJECTIVE
  To present a simple method for estimating population-level anti-retroviral therapy (ART) need that does not rely on knowledge of past HIV incidence.
  
  
  METHODS
  A new approach to estimating ART need is developed based on calculating age-specific proportions of HIV-infected adults expected to die within a fixed number of years in the absence of treatment. Mortality data for HIV-infected adults in the pre-treatment era from five African HIV cohort studies were combined to construct a life table, starting at age 15, smoothed with a Weibull model. Assuming that ART should be made available to anyone expected to die within 3 years, conditional 3-year survival probabilities were computed to represent proportions needing ART. The build-up of ART need in a successful programme continuously recruiting infected adults into treatment as they age to within 3 years of expected death was represented by annually extending the conditional survival range.
  
  
  RESULTS
  The Weibull model: survival probability in the infected state from age 15 = exp(-0.0073 × (age - 15)(1.69)) fitted the pooled age-specific mortality data very closely. Initial treatment need for infected persons increased rapidly with age, from 15% at age 20-24 to 32% at age 40-44 and 42% at age 60-64. Overall need in the treatment of naïve population was 24%, doubling within 5 years in a programme continually recruiting patients entering the high-risk period for dying.
  
  
  CONCLUSIONS
  A reasonable projection of treatment need in an ART naive population can be made based on the age and gender profile of HIV-infected people.
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK. basia.zaba@lshtm.ac.uk
authors.forename: Basia
authors.initials: B
authors.lastname: Zaba
authors.forename: Ivan
authors.initials: I
authors.lastname: Kasamba
authors.forename: Sian
authors.initials: S
authors.lastname: Floyd
authors.forename: Raphael
authors.initials: R
authors.lastname: Isingo
authors.forename: Kobus
authors.initials: K
authors.lastname: Herbst
authors.forename: Till
authors.initials: T
authors.lastname: Bärnighausen
authors.forename: Simon
authors.initials: S
authors.lastname: Gregson
authors.forename: Constance
authors.initials: C
authors.lastname: Nyamukapa
authors.forename: Ndoliwe
authors.initials: N
authors.lastname: Kayuni
authors.forename: Jim
authors.initials: J
authors.lastname: Todd
authors.forename: Milly
authors.initials: M
authors.lastname: Marston
authors.forename: Alison
authors.initials: A
authors.lastname: Wringe
mesh_terms: D000293:Adolescent; D000328:Adult; D017954:Africa South of the Sahara / Q000453:epidemiology; D017677:Age Distribution; D000368:Aged; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology* / Q000401:mortality; D006301:Health Services Needs and Demand / Q000706:statistics & numerical data*; D006801:Humans; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D009026:Mortality; D015995:Prevalence; D055815:Young Adult
chemical_list: D044966:Anti-Retroviral Agents