title: AIDS across Europe, 1994-98: the EuroSIDA study.
abstract: BACKGROUND
  The clinical presentation of HIV-1 related diseases could have changed after the introduction of highly active antiretroviral treatment (HAART). We aimed to assess changes over time in the incidence of ADIs overall and within CD4 lymphocyte count strata, the relationship with treatment and degree of immunodeficiency at diagnosis of ADIs.
  
  
  METHODS
  We did a prospective observational multicentre study of over 7300 patients in 52 European HIV-1 outpatient clinics. Incidence rates per 100 patient-years of observation were calculated.
  
  
  RESULTS
  In total, we recorded 1667 new ADIs; the incidence of ADIs declined from 30.7 per 100 patient-years of observation during 1994 (95% CI 28.0-33.4) to 2.5 per 100 patient-years of observation during 1998 (95% CI 2.0-3.0, p<0.0001, test for trend). Median CD4 lymphocyte count at diagnosis of a new ADI increased from 28 cells/microL to 125 cells/microL between 1994 and 1998 (p<0.0001), yet a steep decline in the rate of ADIs was seen after stratification by latest CD4 lymphocyte count within each year (< or = 50, 51-200, and > 200 cells/microL). Patients on HAART had a lower rate of ADIs than patients not on this treatment within each CD4 lymphocyte count strata. The proportion of ADIs attributable to cytomegalovirus retinitis and Mycobacterium avium complex declined over time (p=0.0058 and 0.0022, respectively), whereas the proportion of diagnoses attributable to non-Hodgkin lymphoma has increased (p<0.0001). In 1994, less than 4% of ADIs were non-Hodgkin lymphoma, in 1998 the proportion was almost 16%. This condition has become one of the most common ADIs in patients on HAART.
  
  
  CONCLUSIONS
  Our findings lend support to the idea that treatment regimens can lower the incidence of ADIs. The immediate risk of an ADI for a given CD4 lymphocyte count has declined over time and is lower among patients on HAART. Long-term follow-up of patients on combination treatment is essential to monitor the incidence of new and emerging diagnoses.
authors.affiliation: Royal Free Centre for HIV Medicine, Royal Free and University College London Medical School, UK.
authors.forename: A
authors.initials: A
authors.lastname: Mocroft
authors.forename: C
authors.initials: C
authors.lastname: Katlama
authors.forename: A M
authors.initials: AM
authors.lastname: Johnson
authors.forename: C
authors.initials: C
authors.lastname: Pradier
authors.forename: F
authors.initials: F
authors.lastname: Antunes
authors.forename: F
authors.initials: F
authors.lastname: Mulcahy
authors.forename: A
authors.initials: A
authors.lastname: Chiesi
authors.forename: A N
authors.initials: AN
authors.lastname: Phillips
authors.forename: O
authors.initials: O
authors.lastname: Kirk
authors.forename: J D
authors.initials: JD
authors.lastname: Lundgren
mesh_terms: D017088:AIDS-Related Opportunistic Infections / Q000453:epidemiology; D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy / Q000453:epidemiology*; D019380:Anti-HIV Agents / Q000627:therapeutic use; D018791:CD4 Lymphocyte Count / Q000706:statistics & numerical data; D015331:Cohort Studies; D005060:Europe / Q000453:epidemiology; D015497:HIV-1; D006801:Humans; D015994:Incidence; D015337:Multicenter Studies as Topic; D011446:Prospective Studies; D013997:Time Factors; D019562:Viral Load
chemical_list: D019380:Anti-HIV Agents