Table 3.
Univariate and multivariate logistic regression analyses for primary analysis and all sensitivity analyses
| Unadjusted modela [OR (95 % CI)] | Adjusted modela [OR (95 % CI)] | |
|---|---|---|
| Primary analysis | ||
| Achieved undetectable viral loadb during baseline regimen | 0.67 (0.45–0.98) | 0.84 (0.53–1.34) |
| Achieved undetectable viral load between starting baseline regimen and last date of follow-up | 0.46 (0.30–0.72) | 0.82 (0.48–1.40) |
| Sensitivity analyses | ||
| Balancing follow-up time between treatment groups | ||
| Patients with at least 12 months of follow-up | ||
| Achieved undetectable viral load during baseline regimen | 0.77 (0.48–1.22) | 0.91 (0.54–1.51) |
| Achieved undetectable viral load between starting baseline regimen and last date of follow-up | 0.51 (0.28–0.91) | 0.55 (0.30–1.03) |
| Patients starting regimen 2009 or later | ||
| Achieved undetectable viral load during baseline regimen | 0.66 (0.42–1.03) | 0.91 (0.53–1.55) |
| Achieved undetectable viral load between starting baseline regimen and last date of follow-up | 0.53 (0.32–0.87) | 0.99 (0.53–1.87) |
| Alternative definition of effectiveness | ||
| Achieved suppressed viral load (<400 copies/mL) | ||
| Achieved suppressed viral load during baseline regimen | 0.83 (0.50–1.38) | 0.95 (0.54–1.66) |
| Achieved suppressed viral load between starting baseline regimen and last date of follow-up | 0.51 (0.26–0.97) | 0.98 (0.45–2.12) |
| Accounting for baseline viral load | ||
| Baseline viral load >200 copies/mL | ||
| Achieved undetectable viral load during baseline regimen | 0.67 (0.37–1.21) | 0.97 (0.49–1.93) |
| Achieved undetectable viral load between starting baseline regimen and last date of follow-up | 0.42 (0.23–0.75) | 0.88 (0.44–1.76) |
| Baseline viral load ≤200 copies/mL | ||
| Achieved undetectable viral load during baseline regimen | 0.78 (0.42–1.45) | 1.10 (0.54–2.23) |
| Achieved undetectable viral load between starting baseline regimen and last date of follow-up | 0.65 (0.28–1.52) | 1.34 (0.49–3.66) |
CI confidence interval, OR odds ratio
aAll models compare a regimen of abacavir/lamivudine and darunavir/ritonavir with a regimen of abacavir/lamivudine and a protease inhibitor besides darunavir/ritonavir (reference)
bSuppression of viral load to undetectable limit is the primary outcome of interest for this study. Undetectable measured as below assay limit (range <20 to <75 copies/mL)