TABLE 1.
Characteristics of subjects at the time of virologic failure (continuous variables), sampled from a cohort of HIV*-infected persons in San Francisco, California, 2000–2004†
| Characteristic | First quartile | Median | Mean | Third quartile | No. with missing data |
|---|---|---|---|---|---|
| Plasma HIV RNA level (copies/ml) | 365.5 | 4,317 | 34,190 | 24,940 | 0 |
| CD4 T-cell count (cells/μl) | 175.5 | 261.5 | 321 | 428.8 | 0 |
| CD8 T-cell count (cells/μl) | 726.8 | 1,022 | 1,168 | 1,497 | 0 |
| % average adherence (self-report) | 100 | 100 | 92.4 | 100 | 0 |
| Year diagnosed with HIV | 1986 | 1989 | 1989 | 1993 | 2 |
| Age (years) | 44.2 | 50.5 | 49.9 | 55.5 | 0 |
| Year of first antiretroviral treatment | 1991 | 1996 | 1995 | 1997 | 0 |
| Peak HIV RNA level (laboratory records) (copies/ml) | 46,020 | 177,500 | 242,300 | 381,200 | 0 |
| Nadir of CD4 T-cell count (laboratory records) (cells/μl) | 36.3 | 72.5 | 118.3 | 165 | 0 |
| No. of protease inhibitors tried | 2 | 3 | 3.2 | 4 | 0 |
| No. of nucleoside reverse transcriptase inhibitors tried | 4 | 5 | 4.8 | 6 | 0 |
| No. of nonnucleoside reverse transcriptase inhibitors tried | 0 | 1 | 0.9 | 1 | 0 |
*
HIV, human immunodeficiency virus.
†
Among 100 persons (116 episodes) with a known time of viral failure and follow-up for at least 8 months following time of failure.