Predictors of switch to and early outcomes on third-line antiretroviral therapy at a large public-sector clinic in Johannesburg, South Africa

Table 3 Crude and adjusted hazard ratios of switch to third-line (n = 719)

Characteristics at second-line initiation	N, row %	Crude HR 95% CI	P value	aHR 95% CI	P value
Gender
Female	24/480 (5.0%)	1.0		1.0
Male	12/239 (5.0%)	1.01 (0.50–2.01)	0.99	1.09 (0.52–2.29)	0.81
Age, years
18–30	8/156 (5.1%)	1.0		1.0
30–45	20/407 (4.9%)	0.95 (0.42–2.15)	0.90	0.91 (0.39–2.11)	0.82
≥ 45	8/156 (5.1%)	0.95 (0.36–2.54)	0.93	0.89 (0.32–2.49)	0.82
Time on second-line (calculated from start of second-line until 01 August 2012), weeks
< 96	9/317 (2.8%)	1.0		1.0
≥ 96	27/402 (6.7%)	2.37 (1.11–5.03)	0.03*	2.53 (1.03–6.22)	0.04*
Regimen change prior to 01 August 2012
No	20/493 (4.1%)	1.0
Yes	16/226 (7.1%)	1.76 (0.91–3.39)	0.09
Current CD4 count, cells/mm³
< 100	4/49 (8.2%)	2.81 (0.90–8.83)	0.08
100–200	3/61 (4.9%)	1.66 (0.46–5.96)	0.43
200–350	8/131 (6.1%)	2.10 (0.85–5.23)	0.11
≥ 350	11/359 (3.1%)	1.0
Never suppressed on second-line ART prior to August 2012
No	24/505 (4.8%)	1.0		1.0
Yes	9/90 (10.0%)	2.32 (1.08–4.99)	0.03*	3.37 (1.47–7.73)	0.00*
Viral load blips on second-line ART prior to August 2012
0	16/317 (5.1%)	1.0
≥ 1	14/171 (8.2%)	1.64 (0.80–3.36)	0.18
History of TB
No	30/658 (4.6%)	1.0		1.0
Yes	6/61 (9.8%)	2.29 (0.95–5.50)	0.06	1.99 (0.81–4.85)	0.13
Currently on TB treatment
No	34/694 (4.9%)	1.0
Yes	2/25 (8.0%)	1.75 (0.42–7.27)	0.44

ABC abacavir, 3TC lamivudine, FTC emtricitabine, LPVr lopinavir/ritonavir, TDF tenofovir, AZT zidovudine, ddI didanosine, d4T stavudine, HR hazard ratio, aHR adjusted hazard ratio; * p < 0.05

ISSN: 1742-6405