Table.
Factors associated with HIV drug resistance at initiation of antiretroviral treatment (baseline) and at the time of treatment failure.*
| Variables | Total | Resistance at baseline | Resistance at ART failure | New resistance at ART failure | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
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| N | N (%) | OR (95% CI) | P | N (%) | OR (95% CI) | P | N (%) | OR (95% CI) | P | ||
| Age | <25 years | 12 | 2 (17) | 6 (50) | ref | 5 (42) | ref | ||||
| 25–39 years | 57 | 5 (9) | 20 (35) | 0.54 (0.15–1.90) | 0.34 | 18 (32) | 0.65 (0.18–2.32) | 0.50 | |||
| ≥40 years | 16 | 0 (0) | 4 (25) | 0.33 (0.07–1.65) | 0.18 | 4 (25) | 0.47 (0.09–2.34) | 0.35 | |||
|
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| Gender | Male | 47 | 3 (6) | ref | 17 (36) | ref | 17 (36) | ref | |||
| Female | 38 | 4 (11) | 1.73 (0.36–8.23) | 0.49 | 13 (34) | 0.92 (0.37–2.25) | 0.85 | 10 (26) | 0.63 (0.25–1.61) | 0.33 | |
|
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| Baseline CD4 cell counta | 84 | 7 (8) | 0.92 (0.47–1.80) | 0.80 | 30 (35) | 0.70 (0.46–1.05) | 0.09 | 26 (31) | 0.75 (0.49–1.13) | 0.17 | |
|
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| Baseline log10 viral loadb | 85 | 7 (8) | 0.65 (0.21–1.99) | 0.45 | 30 (35) | 2.36 (1.17–4.78) | 0.017 | 27 (32) | 3.02 (1.41–6.49) | 0.0046 | |
|
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| Regionc | Americas | 14 | 2 (14) | ref | 5 (36) | ref | 5 (36) | ref | |||
| Asia | 29 | 2 (7) | 0.44 (0.06–3.54) | 0.44 | 10 (34) | 0.95 (0.25–3.60) | 0.94 | 10 (34) | 0.95 (0.25–3.60) | 0.94 | |
| Africa | 42 | 3 (7) | 0.46 (0.07–3.09) | 0.43 | 15 (36) | 1.00 (0.28–3.53) | 1.00 | 12 (29) | 0.72 (0.20–2.59) | 0.62 | |
|
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| Regimend | EFV/3TC/ZDV | 66 | 6 (9) | 1.80 (0.20–15.9) | 0.60 | 26 (39) | 2.44 (0.73–8.16) | 0.15 | 24 (36) | 3.05 (0.81–11.5) | 0.10 |
| Other | 19 | 1 (5) | ref | 4 (21) | ref | 3 (16) | ref | ||||
|
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| Education | None | 16 | 2 (13) | 10 (63) | ref | 9 (56) | ref | ||||
| Primary or secondary schooling | 65 | 5 (8) | 19 (29) | 0.25 (0.08–0.78) | 0.017 | 17 (26) | 0.28 (0.09–0.85) | 0.026 | |||
| Post-secondary schooling | 4 | 0 (0) | 1 (25) | 0.20 (0.02–2.39) | 0.20 | 1 (25) | 0.26 (0.02–3.06) | 0.28 | |||
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| Marital status | Married | 81 | 6 (7) | ref | 28 (35) | ref | 25 (31) | ref | |||
| Not married | 4 | 1 (25) | 4.17 (0.37–46.4) | 0.25 | 2 (50) | 1.89 (0.25–14.2) | 0.53 | 2 (50) | 2.24 (0.30–16.8) | 0.43 | |
|
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| Number sex partners | 0–1 | 82 | 7 (9) | 29 (35) | ref | 26 (32) | ref | ||||
| >1 | 3 | 0 (0) | 1 (33) | 0.91 (0.08–10.5) | 0.94 | 1 (33) | 1.08 (0.09–12.4) | 0.95 | |||
|
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| Baseline resistance | Yes | 7 | 7 (100) | – | 4 (57) | 3.19 (0.66–15.4) | 0.15 | ||||
| No | 78 | 23 (29) | – | 23 (29) | ref | ||||||
The analyses included the 85 HIV-infected index participants in the early ART arm of HPTN who failed ART (see text).
Abbreviations: ART: antiretroviral therapy; N: number; OR: odds ratio; CI: confidence interval; P: P-value; ref: reference group; EFV: efavirenz; 3TC: lamivudine; ZDV: zidovudine; VS: viral suppression; mo: months.
P-values <0.05 are bolded. Regression models could not be generated if any cell was 0 for the categorical variable.
Assessed as increments of 100 CD4-positive cells/mm3.
Assessed as increments of log10 viral load.
The 85 participants had the following HIV subtypes: 69 (81.2%) subtype C (Malawi [N=29], India [N=28], Zimbabwe [N=7], South Africa [N=3], and Brazil [N=2]), eight subtype B (Brazil), three subtype F1 (Brazil), one subtype A2 (Kenya), two A1 (Kenya), one CRF1_AE (Thailand), and one CRF12_BF (Brazil).
The majority of participants who started ART on the EFV/3TC/ZDV regimen (with the exception of pregnant women) received a fixed-dose formulation of these drugs.