Table 2.

Unadjusted and Adjusted Hazard Ratios for Attrition (N = 629)

Characteristic	Unadjusted Hazard Ratio (95% CI)	P Value	Adjusted Hazard Ratio (95% CI)	P Value
Demographics
Age, y
≤25	(ref)	<.001*	(ref)	<.001*
26–35	0.61 (.38–.98)		0.35 (.23–.52)
36–45	0.48 (.29–.80)		0.25 (.16–.39)
>45	0.20 (.07–.60)		0.11 (.03–.38)
Female	0.83 (.49–1.40)	.489	0.50 (.28–.90)	.021
Primary schooling or less	1.05 (.81–1.36)	.726
At least 1 child	0.90 (.68–1.19)	.464
Married	1.07 (.75–1.53)	.72
Sexual risk factors
Multiple sex partners in last 6 mo	0.93 (.67–1.29)	.674
Risky sexual behavior in last 6 mo	1.16 (.90–1.50)	.245	1.29 (.99–1.68)	.060
Injection risk factors
Ever used flashblood	1.06 (.68–1.66)	.797
Shared needles at last injection	1.26 (.89–1.78)	.192
If shared needles, cleaned needles with bleach	0.82 (.42–1.63)	.579
Shared other equipment at last injection	1.04 (.69–1.57)	.843
Polysubstance use	1.17 (.90–1.52)	.252
Mental health history
High substance dependence	1.04 (.73–1.47)	.841
Depression in last 30 d	0.86 (.63–1.17)	.326
Anxiety in last 30 d	0.90 (.66–1.22)	.488
Hopkins depression score	1.01 (.83–1.22)	.943
Hopkins overall score	0.99 (.80–1.23)	.947
History of abuse
Any history of physical abuse	1.06 (.72–1.56)	.759
Any history of sexual abuse	1.84 (.82–4.46)	.14	2.84 (1.24–6.51)	.014
Criminal history
Ever arrested	1.10 (.85–1.43)	.449
Methadone dose at initiation
<40 mg	(ref)	<.001*	(ref)	<.001*
40–85 mg	0.60 (.45–.81)		0.50 (.37–.68)
>85 mg	0.47 (.34–.66)		0.41 (.29–.59)

Abbreviations: CI, confidence interval; ref, reference.

* Test for trend from group-linear term.