Lack of consistency between five definitions of nonprogression in cohorts of HIV-infected seroconverters.
AIDS
; 10(9): 959-65, 1996 Aug.
Article
en En
| MEDLINE
| ID: mdl-8853728
ABSTRACT
OBJECTIVE:
To identify appropriate criteria for characterizing HIV-infected nonprogressors.DESIGN:
Five definitions were compared as follows (1) last CD4 count > 500 x 10(6)/l; (2) two most recent CD4 counts > 500 x 10(6)/l; (3) calculated CD4 count based on linear regression > 500 x 10(6)/l; (4) CD4 slope > or = 0 with no antiretroviral use; (5) all CD4 counts > 500 x 10(6)/l, decline in CD4 slope < 5 cells per year, no antiretroviral use.PARTICIPANTS:
Five prospective cohorts of homosexual men with documented dates of HIV-1 seroconversion. MAIN OUTCOMEMEASURES:
Proportions of nonprogressors were calculated 7, 8, 9 and 10 years following seroconversion (n = 285). Definitions were evaluated with respect to consistency over time and across sites. Subjects lacking CD4 counts within 3 years preceding end of follow-up were excluded.RESULTS:
Across sites, proportions of nonprogressors ranged from 1% (definition 5) to 17.5% (definition 1) 10 years after seroconversion. Definitions based on absolute CD4 counts (definitions 1-3) had higher proportions and were less consistent than those based on stable slopes (definitions 4 and 5). For each definition, proportions decreased as follow-up increased, but were most stable for definition 4 (3%). Site differences decreased as follow-up increased, but remained nearly threefold for definitions 1-3. None of the definitions classified the same subjects as nonprogressors at any timepoint.CONCLUSIONS:
Observations regarding nonprogression are highly dependent on the definition and the duration of follow-up. Our findings highlight methodological challenges which will need to be overcome in natural history studies of nonprogression.
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Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Linfocitos T CD4-Positivos
/
Infecciones por VIH
Tipo de estudio:
Etiology_studies
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Incidence_studies
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Observational_studies
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Prognostic_studies
/
Risk_factors_studies
Límite:
Humans
/
Male
Idioma:
En
Revista:
AIDS
Asunto de la revista:
SINDROME DA IMUNODEFICIENCIA ADQUIRIDA (AIDS)
Año:
1996
Tipo del documento:
Article
País de afiliación:
Canadá