Estimating AIDS-free survival in a severely immunosuppressed asymptomatic HIV-infected population in the era of antiretroviral triple combination therapy. Swiss HIV Cohort Study.
BACKGROUND
Antiretroviral triple combination therapies have been evaluated in randomized controlled trials and cohort studies. Little is known about their impact on asymptomatic, severely immunosuppressed, HIV-infected individuals in a real world population.


OBJECTIVE
To describe disease progression in a broad asymptomatic population of HIV-infected individuals with a CD4 count <100 cells/mm3 before and after the introduction of combination triple therapy.


METHODS
Six-month homogenous Markov chain consisting of four recurrent AIDS-free states and one absorbing AIDS state: (1) CD4 count > or =100 cells/mm3, (2) CD4 count 75 to 99 cells/mm3, (3) CD4 count 50 to 74 cells/mm3, (4) CD4 count 0 to 49 cells/mm3, and AIDS.


METHODS
Swiss HIV Cohort Study database.


METHODS
A total of 1027 patients contributed to 2634 pairs of 6-month observations from 1993 to 1995, and 681 patients contributed to 2077 pairs of 6-month observations from 1996 to 1997.


METHODS
AIDS-free survival probabilities and the expected AIDS-free survival time.


RESULTS
The expected number of AIDS-free months in a 3-year period was 17 (95% confidence interval [CI], 16-19) for patients starting in state 4 prior to 1996 versus 26 months (95% CI, 24-28) for patients starting in state 4 after 1996. For these two time periods, the corresponding expected numbers of AIDS-free months were 21 (95% CI, 20-22) versus 30 (95% CI, 28-32) for state 3 and 23 (95% CI, 21-24) versus 33 (95% CI, 32-34) for state 2.


CONCLUSIONS
Expected 3-year AIDS-free survival in severely immunosuppressed individuals with CD4 counts <100 cells/mm3 improved significantly between 1993 to 1995 and 1996 to 1997.
Sendi
P P
PP
Internal Medicine Outpatient Department, University of Basel, Switzerland.
Bucher
H C
HC
Craig
B A
BA
Pfluger
D
D
Battegay
M
M
D000163:Acquired Immunodeficiency Syndrome / Q000188:drug therapy* / Q000276:immunology; D000293:Adolescent; D000328:Adult; D000368:Aged; D019380:Anti-HIV Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D006801:Humans; D007108:Immune Tolerance; D008875:Middle Aged; D011446:Prospective Studies; D017741:Survivors
D019380:Anti-HIV Agents