title: Heterogeneity in outcomes of treated HIV-positive patients in Europe and North America: relation with patient and cohort characteristics.
abstract: BACKGROUND
  HIV cohort collaborations, which pool data from diverse patient cohorts, have provided key insights into outcomes of antiretroviral therapy (ART). However, the extent of, and reasons for, between-cohort heterogeneity in rates of AIDS and mortality are unclear.
  
  
  METHODS
  We obtained data on adult HIV-positive patients who started ART from 1998 without a previous AIDS diagnosis from 17 cohorts in North America and Europe. Patients were followed up from 1 month to 2 years after starting ART. We examined between-cohort heterogeneity in crude and adjusted (age, sex, HIV transmission risk, year, CD4 count and HIV-1 RNA at start of ART) rates of AIDS and mortality using random-effects meta-analysis and meta-regression.
  
  
  RESULTS
  During 61 520 person-years, 754/38 706 (1.9%) patients died and 1890 (4.9%) progressed to AIDS. Between-cohort variance in mortality rates was reduced from 0.84 to 0.24 (0.73 to 0.28 for AIDS rates) after adjustment for patient characteristics. Adjusted mortality rates were inversely associated with cohorts' estimated completeness of death ascertainment [excellent: 96-100%, good: 90-95%, average: 75-89%; mortality rate ratio 0.66 (95% confidence interval 0.46-0.94) per category]. Mortality rate ratios comparing Europe with North America were 0.42 (0.31-0.57) before and 0.47 (0.30-0.73) after adjusting for completeness of ascertainment.
  
  
  CONCLUSIONS
  Heterogeneity between settings in outcomes of HIV treatment has implications for collaborative analyses, policy and clinical care. Estimated mortality rates may require adjustment for completeness of ascertainment. Higher mortality rate in North American, compared with European, cohorts was not fully explained by completeness of ascertainment and may be because of the inclusion of more socially marginalized patients with higher mortality risk.
authors.affiliation: School of Social and Community Medicine, University of Bristol, Bristol, UK. m.t.may@bristol.ac.uk
authors.forename: Margaret T
authors.initials: MT
authors.lastname: May
authors.forename: Robert S
authors.initials: RS
authors.lastname: Hogg
authors.forename: Amy C
authors.initials: AC
authors.lastname: Justice
authors.forename: Bryan E
authors.initials: BE
authors.lastname: Shepherd
authors.forename: Dominique
authors.initials: D
authors.lastname: Costagliola
authors.forename: Bruno
authors.initials: B
authors.lastname: Ledergerber
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Thiébaut
authors.forename: M John
authors.initials: MJ
authors.lastname: Gill
authors.forename: Ole
authors.initials: O
authors.lastname: Kirk
authors.forename: Ard
authors.initials: A
authors.lastname: van Sighem
authors.forename: Michael S
authors.initials: MS
authors.lastname: Saag
authors.forename: Gemma
authors.initials: G
authors.lastname: Navarro
authors.forename: Paz
authors.initials: P
authors.lastname: Sobrino-Vegas
authors.forename: Fiona
authors.initials: F
authors.lastname: Lampe
authors.forename: Suzanne
authors.initials: S
authors.lastname: Ingle
authors.forename: Jodie L
authors.initials: JL
authors.lastname: Guest
authors.forename: Heidi M
authors.initials: HM
authors.lastname: Crane
authors.forename: Antonella
authors.initials: A
authors.lastname: D'Arminio Monforte
authors.forename: Jörg J
authors.initials: JJ
authors.lastname: Vehreschild
authors.forename: Jonathan A C
authors.initials: JA
authors.lastname: Sterne
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy / Q000401:mortality; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D005060:Europe / Q000453:epidemiology; D005260:Female; D015658:HIV Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality*; D006679:HIV Seropositivity / Q000188:drug therapy / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009656:North America / Q000453:epidemiology; D011379:Prognosis; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult
chemical_list: D044966:Anti-Retroviral Agents