Craib KJ, Schechter MT, Le TN, Montaner JS, Sestak P, Douglas B, Weaver MS, McLeod WA, O'Shaughnessy M; International Conference on AIDS.
Int Conf AIDS. 1990 Jun 20-23; 6: 254 (abstract no. F.C.693).
The Vancouver Lymphadenopathy-AIDS Study, University of British Columbia and St. Paul's Hospital, Vancouver, Canada
OBJECTIVE: To determine the rate of progression to AIDS using imputed and crude estimates of lead time infection in a cohort of seroprevalent homosexual men. METHODS: We divided our cohort into 233 seropositives at entry (SP) and 119 who seroconverted under observation (SI). Lead time HIV infection was imputed for SP using a model based on serial IgG, IgA and CD4 counts obtained from SI: Imputed lead time (ILT) = exp (2.242 + 0.00097*IgA- 0.00037*CD4 + 0.00041*IgG). Progression to AIDS was calculated with Kaplan-Meier methods. RESULTS: The estimated mean ILT was 18.5 months (S.D. = 7.6, range = 8-80). AIDS progression curves are shown SP* (using ILT), SP+ (using 18 mos), SP (unadjusted), and for SI. Estimated progression at 7 years in SP* and SP+ were 29.5% and 31.3% respectively. Kaplan-Meier curves were similar for SP*, SP+, and SI. Use of imputed lead time in SP* allowed an estimate of 44.1% for cumulative progression at 101 months. TABULAR DATA, SEE ABSTRACT VOLUME. CONCLUSION: Most cohort studies involve large numbers of seroprevalent individuals. Use of seroprevalent cohorts yield biased progression rates. We have used a very simple model which has allowed our seroprevalent cohort to be incorporated into estimations of disease progression.
Publication Types:
Keywords:
- Acquired Immunodeficiency Syndrome
- CD4 Lymphocyte Count
- Cohort Studies
- Communicable Diseases
- Disease Progression
- HIV Infections
- Homosexuality
- Humans
- Male
- epidemiology
Other ID:
UI: 102184630
From Meeting Abstracts