Table 2. Multivariate Cox's proportional hazards regression model of independent predictors of treatment failure for first-line HAART, adjusted for age, sex, baseline clinical status, viral load and CD4 count, and stratified by year of starting first-line HAART.

Table 2	Baseline CD4 ≤100N = 1547			Baseline CD4 101–200N = 1503			Baseline CD4 201–350N = 1815			Baseline CD4 >350N = 676
	Failed first-line therapyN = 331			Failed first-line therapyN = 255			Failed first-line therapyN = 278			Failed first-line therapyN = 111
Variables	HR	95% CI	Score statisticp-value	HR	95% CI	Score statisticp-value	HR	95% CI	Score statisticp-value	HR	95% CI	Score statisticp-value
Sex:FemaleMale	1.171	(0.89 to 1.53)	0.256	1.591	(1.19 to 2.13)	0.002	1.411	(1.06 to 1.88)	0.020	1.961	(1.21 to 3.18)	0.007
Age	0.99	(0.97 to 0.99)	0.035	0.99	(0.97 to 1.01)	0.174	1.00	(0.99 to 1.01)	0.816	0.98	(0.96 to 1.01)	0.147
Clinical statusAIDSNon AIDS	1.321	(1.04 to 1.67)	0.023	1.541	(1.19 to 2.00)	0.001	1.321	(1.01 to 1.72)	0.041	1.091	(0.69 to 1.71)	0.719
First line regimensOther2NRTIs+PI2NRTIs+2PI2NRTIs+PIboosted2NRTIs+NNRTI	2.181.491.320.541	(1.56 to 3.03)(1.06 to 2.09)(0.18 to 2.09)(0.30 to 0.97)	<0.0010.0200.7850.037	2.182.183.760.551	(1.55 to 3.07)(1.51 to 3.16)(1.03 to 13.80)(0.29 to 1.05)	<0.001<0.0010.0460.068	1.542.170.740.861	(1.02 to 2.31)(1.56 to 3.01)(0.10 to 5.35)(0.49 to 1.50)	0.040<0.0010.7610.597	1.491.730.001.511	(0.79 to 2.80)(1.09 to 2.74)(-)(0.69 to 3.28)	0.2180.0210.9860.303
Extrapolated and estimated median time (IQR) to failure for first-line HAART regimens (in days)
Other regimens2NRTIs+PI2NRTIs+2PI2NRTIs+PIboosted2NRTIs+NNRTI	2528 (1118 to 3938)1791 (770 to 2811)1485 (742 to 2227)4218 (2086 to 6350)4707 (2097 to 7317)			2501 (1143 to 3859)2394 (1094 to 3694)231 (581 to 391)7051 (3425 to 10677)5600 (2522 to 8678)			2640 (1295 to 3986)2676 (1211 to 4141)604 (302 to 906)4607 (2266 to 6948)5211 (2460 to 7962)		1573 (845 to 2302)2678 (1244 to 4112)Not possible to estimate2324 (1112 to 3536)5072 (2362 to 7783)