Table 2.

Associations with Management Strategy Choice in Children with Virologic Failure, Relative to Remaining on a Failing Regimen

	aHR (95% CI)*
Characteristics at virologic failure	Switch to second- line	Switch to holding regimen	Treatment interruption
Type of first-line regimen (NNRTI-based vs PI-based)	8.86 (5.96–13.18)	3.18 (1.95–5.18)	1.87 (1.28–2.73)
Gender (female vs male)	0.81 (0.65–1.01)	0.83 (0.58–1.20)	1.13 (0.86–1.48)
Calendar year of ART start	1.06 (0.99–1.13)	1.32 (1.19–1.46)	1.10 (1.02–1.19)
Type of facility (primary vs secondary/tertiary)	2.97 (1.99–4.44)	2.73 (1.31–5.69)	22.78 (5.62–92.31)
Age in years at failure	1.07 (1.01–1.13)	0.95 (0.85–1.06)	1.20 (1.12–1.28)
Viral load at failure (copies/ml)
1000–5000	1	1	1
5000–10000	1.73 (0.80–3.75)	1.25 (0.43–3.69)	3.18 (1.06–9.52)
10000–50000	1.63 (0.77–3.46)	2.72 (1.06–6.95)	5.72 (2.42–13.50)
>50000	1.45 (0.68–3.10)	0.44 (0.16–1.16)	5.93 (2.54–13.84)
Viral load at failure x Age in years at failure
VL >1000 and VL<5000 x Age at failure	1	1	1
VL>=5000 and VL <10000 x Age at failure	0.95 (0.88–1.03)	0.99 (0.86–1.14)	0.76 (0.67–0.86)
VL>=10000 and VL <50000 x Age at failure	0.95 (0.88–1.02)	0.86 (0.75–0.99)	0.82 (0.75–0.89)
VL>=50000 x Age at failure	0.94 (0.87–1.01)	1.08 (0.95–1.22)	0.74 (0.68–0.82)
Time-varying covariates
Current Log10VL (per 1 Log10 increase)	1.58 (1.38–1.79)	2.33 (1.89–2.88)	2.18 (1.89–2.52)

^*Hazard ratios derived from pooled unweighted multinomial logistic regression fit on subsample of person-weeks of follow-up during which a switch to new regimen had not yet occurred

aHR: adjusted hazard ratio