Table 2. Univariate analysis comparing patients with and without major protease inhibitor (PI) drug resistance mutations.
| Features: | With major PI mutations | Without major PI mutations | |
|---|---|---|---|
| (Median [IQR]) | (Median [IQR]) | ||
| n = 32 | n = 33 | p value | |
| Age and time period (months) 1 | |||
| - Age at ART initiation | 11.4 [7.6; 19.1] | 17.3 [7.9; 28.0] | 0.18 |
| - Duration of ART | 50.2 [33.2; 64.7] | 25.5 [18.4; 48.2] | 0.003 |
| - Duration of PI exposure | 34.1 [25.1; 51.2] | 20.7 [15.2; 25.5] | 0.001 |
| - Duration of virological failure* | 45.0 [28.4; 59.5] | 22.1 [16.8; 47.6] | 0.005 |
| Anthropometry (baseline) 2, ** | |||
| - Weight-for-age Z-score | -3.0 [-3.7; -1.9] | -2.0 [-3,5; -0.9] | 0.039 |
| - Height- for-age Z-score | -3.2 [-4.6; -2.7] | -3.0 [-3.5; -1.8] | 0.05 |
| - BMI-for-age Z-score | -0.7 [-2.5; 0.1] | -0.6 [-2.2; 0.7] | 0.45 |
| CD4 (baseline) 3 | |||
| - Absolute CD4 count | 560 [192; 911] | 548 [281; 828] | 0.85 |
| - CD4% | 13.7 [8.1; 20.1] | 14.5 [10.8; 19.5] | 0.74 |
| Log10 VL (baseline) 4 | 5.98 [5.55; 6.48] | 5.91 [5.18; 6.38] | 0.35 |
| HIV VL suppression | |||
| - Months to LDL (if suppressed)5 | 15.1 [12.4; 27.0] | 6.5 [4.6; 8.6] | 0.014 # |
| Associated mutations | |||
| - Nr of minor PI mutations1 | 1.0 [1.0; 2.0] | 0.0 [0.0; 0.0] | <0.001 |
| Nr (%) | Nr (%) | ||
| VL in categories (baseline) 4 | |||
| - <5 log10 | 2 (6.9%) | 5 (16.7%) | |
| - 5–6 log10 | 11 (37.9%) | 10 (33.3%) | 0.612 |
| - ≥6 log10 | 16 (55.2%) | 15 (50.0%) | |
| HIV VL suppression | |||
| - VL ever LDL (‘undetectable’)1 | 15 (47%) | 13 (39%) | 0.72 |
| - LDL by 12 months on ART5 | 3 (20.0%) | 11 (84.6%) | 0.001 |
| TB treatment | |||
| - On TB treatment while on ART2 | 25 (83.3%) | 18 (58.1%) | 0.036 |
| Time on TB treatment 2 | |||
| - Never/prior to ART (completed) | 5 (16.7%) | 13 (42.0%) | Ref |
| - At ART initiation | 18 (60.0%) | 13 (41.9%) | 0.048 |
| - After ART initiation | 7 (23.3%) | 5 (16.1%) | 0.12 |
| PI use during TB co-treatment | |||
| - Ever on RTV-sPI 6 | 18 (72.0%) | 7 (38.9%) | 0.038 |
| - Ever on ddLPV/r 7 | 10 (41.7%) | 8 (50.0%) | 0.85 |
| - Ever on LPV/R+ 8 | 2 (8.3%) | 3 (16.7%) | 0.46 |
| Associated mutations 9 | |||
| - Any NRTI mutations | 31 (100%) | 31 (93.9%) | 0.49 |
| - Any TAMs | 11 (35.5%) | 5 (15.2%) | 0.07 |
| - Any NNRTI mutations | 15 (48.4%) | 14(42.4%) | 0.82 |
Data collected from 651, 612, 603, 594, 285, 436, 407, 428 and 649 patients respectively
Abbreviations: ART = antiretroviral therapy; PI = protease inhibitors; IQR = interquartile range; BMI = body mass index; CD4 = CD4+ T-cell count in cells/mm3; CD4% = CD4 percentage; VL = HIV viral load; LDL = lower than detectable level; Nr = number; TB = tuberculosis; Ref = reference value; RTV-sPI = ritonavir as full-dose single protease inhibitor; ddLPV/r = double-dose boosted lopinavir; LPV/R+ = super-boosted lopinavir; NRTI = nucleoside reverse transcriptase inhibitor; TAMs = thymidine analogue mutations; NNRTI = non-nucleoside reverse transcriptase inhibitor
*From first failure time point (using LDL cut-off & >6 months on ART) to date of genotype
**Age- and sex-adjusted anthropometry according to WHO growth standards [22]
#Corresponding p-value for VL<1000 = 0.036