Table 1.
Characteristics of NHS Participants Evaluated for Associations With CD4+ T-Cell Count Normalization and AIDS According to Timing of ARTa
| Characteristic | All Participants | Timing of ART From EDSb | Timing of ART From Study Entryb | |||||
|---|---|---|---|---|---|---|---|---|
| Earlier | Later | P Valuec | Earlier | Later | P Valuec | |||
| No. of participants, (%) | 1119 (100.0) | 292 (26.1) | 827 (73.9) | 645 (57.6) | 474 (42.4) | |||
| Male, No. (%) | 1066 (95.3) | 284 (97.3) | 782 (94.6) | .06 | 623 (96.6) | 443 (93.5) | .01 | |
| Ethnicity, No. (%) | .48 | .57 | ||||||
| European American | 497 (44.4) | 121 (41.4) | 376 (45.5) | 282 (43.7) | 215 (45.4) | |||
| African American | 476 (42.5) | 130 (44.5) | 346 (41.8) | 273 (42.3) | 203 (42.8) | |||
| Other | 146 (13.0) | 41 (14.1) | 105 (12.7) | 90 (14.0) | 56 (11.8) | |||
| Age at ART initiation, median (IQR), y | 31 (29–37) | 29 (24–34) | 32 (28–38) | <.001 | 30 (26–36) | 32 (28–38) | <.001 | |
| Time interval, median (IQR), mo | ||||||||
| From last documented negative to first documented positive HIV-1 test | 15.0 (9.9–24.2) | 10.3 (6.2–14.0) | 18.8 (11.7–27.7) | <.001 | 15.6 (9.7–25.1) | 15.0 (10.0–23.3) | .27 | |
| From EDS to study entry | 10.0 (6.8–15.2) | 6.4 (4.4–8.4) | 12.4 (8.4–17.7) | <.001 | 9.6 (6.3–15.1) | 10.5 (7.6–15.4) | .07 | |
| From EDS to ART initiation | 21.3 (11.7–42.8) | 7.9 (5.8–9.9) | 30.1 (18.6–56.8) | <.001 | 7.9 (5.8–9.9) | 30.1 (18.6–54.8) | <.001 | |
| From study entry to ART initiation | 6.9 (0.7–29.6) | 0.5 (0.2–1.7) | 15.8 (4.2–40.0) | <.001 | 1.1 (0.3–4.7) | 35.4 (21.9–58.7) | <.001 | |
| From ART initiation to VL suppression | 5.8 (2.1–28.9) | 4.9 (2.1–14.6) | 6.2 (2.1–37.6) | .004 | 5.1 (2.1–20.6) | 7.0 (2.2–40.0) | .01 | |
| Study entry CD4+, median (IQR), cells/μL | 456 (329–613) | 379 (275–520) | 492 (370–647) | <.001 | 381 (282–515) | 575 (447–731) | <.001 | |
| Study entry CD4+ ≥500 cells/μL, No. (%) | 483 (43.2) | 81 (27.7) | 402 (48.6) | <.001 | 176 (27.3) | 307 (64.8) | <.001 | |
| Pre-ART CD4+, median (IQR), cells/μL | 358 (271–462) | 382 (285–509) | 350 (265–449) | .01 | 364 (277–462) | 350 (264–462) | .30 | |
| Pre-ART CD4+ ≥500 cells/μL, No. (%) | 221 (19.8) | 77 (26.4) | 144 (17.4) | <.001 | 133 (20.6) | 88 (18.6) | .39 | |
| Study entry VL, median (IQR), log10 copies/mL | 4.4 (3.9–4.9) | 4.8 (4.3–5.1) | 4.3 (3.8–4.8) | <.001 | 4.7 (4.2–5.0) | 4.1 (3.6–4.6) | <.001 | |
| Pre-ART VL, median (IQR), log10 copies/mL | 4.6 (4.1–5.0) | 4.8 (4.3–5.0) | 4.5 (4.0–4.9) | <.001 | 4.7 (4.2–5.0) | 4.5 (4.0–4.9) | <.001 | |
| Duration of VL-suppressive ART, median (IQR), yd | 4.7 (2.5–8.0) | 4.4 (2.4–7.8) | 4.7 (2.6–8.1) | .23 | 4.7 (2.4–8.0) | 4.7 (2.7–8.0) | .59 | |
| Achieving CD4+ ≥900 cells/μL, No. (%) | 346 (30.9) | 112 (38.4) | 234 (28.3) | .001 | 228 (35.4) | 118 (24.9) | <.001 | |
| Achieving CD4+ ≥900 cells/μL, starting ART with CD4+ ≥500 cells/μL, No. (%) | 154 (69.7) | 64 (83.1) | 90 (62.5) | .001 | 102 (76.7) | 52 (59.1) | .005 | |
| Achieving CD4+ ≥900 cells/μL, starting ART with CD4+ <500 cells/μL, No. (%) | 192 (21.4) | 48 (22.3) | 144 (21.1) | .70 | 126 (24.6) | 66 (17.1) | .007 | |
| AIDS (1987 criteria), No. (%)e | 58 (5.2) | 8 (2.7) | 50 (6.1) | .03 | 23 (3.6) | 35 (7.4) | .004 | |
| AIDS (1987 criteria), starting ART with CD4+ ≥500 cells/μL, No. (%)f | 4 (1.8) | 2 (2.6) | 2 (1.4) | .52 | 2 (1.5) | 2 (2.3) | .67 | |
| AIDS (1987 criteria), starting ART with CD4+ <500 cells/μL, No. (%)g | 54 (6.0) | 6 (2.8) | 48 (7.0) | .02 | 21 (4.1) | 33 (8.6) | .006 | |
| AIDS (1993 criteria), No. (%)h | 127 (13.3) | 20 (7.8) | 107 (15.3) | .002 | 65 (11.7) | 62 (15.6) | .08 | |
| AIDS (1993 criteria), starting ART with CD4+ ≥500 cells/μL, No. (%)i | 11 (5.1) | 2 (2.6) | 9 (6.3) | .34 | 5 (3.8) | 6 (6.9) | .35 | |
| AIDS (1993 criteria), starting ART with CD4+ <500 cells/μL, No. (%)j | 116 (17.7) | 18 (9.9) | 98 (17.6) | .01 | 60 (14.1) | 56 (18.0) | .15 | |
Abbreviations: ART, antiretroviral therapy; EDS, estimated date of seroconversion; HIV, human immunodeficiency virus; IQR, interquartile range; NHS, US Military HIV Natural History Study; VL, viral load.
During the 10 years of follow-up, a total of 21 195 measurements of CD4+ counts and 21 139 measurements of VL were analyzed. The median number of measurements of CD4+ counts per participant was 17 (IQR, 9–25; range, 2–127), and the median number of measurements of VL per participant was 17 (IQR, 9–26; range, 2–103). The median time between consecutive measurements of CD4+ counts per participant was 102 (IQR, 76–164) days and of VL per participant, 102 (75–167) days.
Earlier ART was defined as initiating ART within 12 months of EDS or study entry; and later ART was defined as initiating ART more than 12 months after EDS or study entry.
P values were calculated with the use of the t test, Mann-Whitney test, or χ2 test as appropriate.
The duration of VL-suppressive ART was indexed from the date of starting ART.
All participants were AIDS (1987 criteria) free prior to ART initiation, and AIDS development (1987 criteria) was evaluated in these patients.
Participants starting ART with CD4+ counts of greater than or equal to 500 cells/μL were evaluated for AIDS development (1987 criteria). All of these participants were AIDS (1987 criteria) free prior to ART initiation.
Participants starting ART with CD4+ counts of less than 500 cells/μL were evaluated for AIDS development (1987 criteria). All of these participants were AIDS (1987 criteria) free prior to ART initiation.
A total of 956 of 1119 participants were AIDS free (1993 criteria) prior to starting ART and were evaluated for development of AIDS (1993 criteria) while receiving VL-suppressive ART; 257 and 558 of these participants, respectively, initiated ART earlier indexed from the EDS and the study entry.
A total of 218 of the 956 participants described aboveh started ART with CD4+ counts of greater than or equal to 500 cells/μL and were evaluated for the development of AIDS (1993 criteria); 76 and 131 of these participants, respectively, initiated ART earlier indexed from the EDS and the study entry.
A total of 738 of the 956 participants described aboveh started ART with CD4+ counts of less than 500 cells/μL and were evaluated for the development of AIDS (1993 criteria); 181 and 427 of these participants, respectively, initiated ART earlier indexed from the EDS and study entry.