Table 2. Adjusted hazard ratio (95% Confidence intervals) of switching from first-line to second-line due to toxicity.

Variables	Model 1: Calendar time		Model 2: Calendar time and regimen type
	Hazard Ratio (95% CI)	P-value	Hazard Ratio (95% CI)	P-value
Calendar period
1996–2000	1.53 (1.37–1.71)	<.0001	1.02 (0.84–1.24)	0.83
2001–2005	1.40 (1.27–1.54)	<.0001	1.00 (0.86–1.16)	0.99
2006–2010	[Reference]		[Reference]
Demographic
Age
5-year increased from 18 years old	1.04 (1.02–1.06)	0.0007	1.04 (1.02–1.07)	0.001
Sex
Male	[Reference]		[Reference]
Female	1.36 (1.18–1.56)	<.0001	1.39 (1.19–1.62)	<.0001
Region of Origin
Netherlands	[Reference]		[Reference]
European	0.86 (0.73–1.02)	0.09	0.87 (0.72–1.04)	0.12
Sub-Saharan Africa	1.04 (0.90–1.21)	0.57	1.02 (0.86–1.19)	0.85
Other	1.01 (0.90–1.13)	0.90	0.99 (0.87–1.12)	0.82
Route of transmission
Heterosexual	1.21 (1.07–1.37)	0.003	0.80 (0.70–0.92)	0.002
MSM	[Reference]		[Reference]
Injecting Drug Use	0.93 (0.64–1.34)	0.69	0.75 (0.49–1.13)	0.17
Other	1.03 (0.86–1.23)	0.78	0.87 (0.72–1.05)	0.14
Clinical
CD4 cell count at start of cART
CD4<200	0.99 (0.86–1.14)	0.90	0.96 (0.82–1.12)	0.61
CD4 201–350	0.93 (0.81–1.07)	0.30	0.96 (0.82–1.12)	0.57
CD4 351–500	[Reference]		[Reference]
CD4>501	1.44 (1.19–1.75)	0.0002	1.24 (0.99–1.56)	0.06
RNA at start of cART
RNA<100 000	[Reference]		[Reference]
RNA 100 000–1 000 000	1.05 (0.96–1.15)	0.32	0.97 (0.87–1.07)	0.50
RNA>1 000 000	1.08 (0.88–1.32)	0.47	0.88 (0.69–1.12)	0.29
cART Type
3TC/d4T+PI			2.16 (1.63–2.86)	<.0001
3TC/d4T+Boosted-PI			3.34 (2.59–4.31)	<.0001
3TC/d4T+NNRTI			2.21 (1.50–3.26)	<.0001
3TC/AZT+PI			1.38 (1.08–1.75)	0.01
3TC/AZT+Boosted-PI			2.31 (1.97–2.70)	<.0001
3TC/AZT+NNRTI			1.55 (1.30–1.86)	<.0001
TDF/FTC or TDF/3TC+Boosted-PI			1.16 (0.97–1.39)	0.10
TDF/FTC or TDF/3TC+NNRTI			[Reference]