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Use of modest financial incentives to improve engagement of drug users in HIV testing and post-test follow-up: results of a randomized controlled

trial Mark Hull1, Charles Otieno1, Marianne Harris1, Joel Singer2, Erin

Ding1, Julia Zhu1, Thomas Kerr1, Evan Wood1, Kate Shannon1, Rolando Barrios1, Robert Hogg1, Nancy Petry3, Julio Montaner1

1. BC Centre for Excellence in HIV/AIDS, Vancouver, BC2. CIHR Canadian HIV Trials Network, Vancouver, BC

3. University of Connecticut Health Center, Farmington, CT, USA

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Background• A significant proportion of HIV+ individuals

(~25% in BC1) are not linked to medical care– Either have not been tested for HIV, or if HIV+

have not been assessed for ART eligibility• Interventions to improve HIV testing rates

among at-risk populations are required to strengthen the HIV care cascade

1. Montaner et al., CROI 2013, #1029

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Background• Conditional cash transfers (Incentives) have been

used successfully to improve goal-related activities amongst IDU populations– Improved rates of completion of TB screening processes

Chaisson, R et al. JAIDS 1996;11:455 , Perlman, D et al J. Urban Health 2003;80:428.– Completion of hepatitis B vaccine series

• Randomized trial of monetary incentive vs. outreach nurses, 69% vs. 23% completion. Seal, K et al. Drug and Alcohol Depend 2003; 71:127.

• Use of incentives for completion of HIV screening has been shown to increase return rates amongst participants in an ED-based program Haukoos, J. Acad Emerg Med 2005;7:617.

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Objective

• To evaluate the efficacy of offering a modest financial incentive linked to HIV testing and post-test counseling in a substance-using population– To evaluate the efficacy of incentives in assessing

ART-eligibility amongst HIV+ individuals not currently engaged in care

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MethodsEntry criteria:• Inclusion

– Age >19 years– At risk for HIV, or HIV+ by self-report with no recent evaluation of

HIV status (CD4 cell count or HIV VL)– Reside in Vancouver– Report drug use at least once in the past 3 months

• alcohol, heroin, cocaine, cocaine/heroin combinations, methamphetamines, injectable morphine and codeine, but excluding isolated marijuana use

• Exclusion– Known HIV with use of antiretrovirals in the past 12 months

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Sample Population

N=301

Control Arm

Incentives Arm

Standard of care counseling and HIV testing plus financial incentive

Randomized 1:1

Standard of care counseling and HIV testing without financial incentive

Study Design

Visit 1(Laboratory

Testing)

Visit 2(Results)

Timeline of follow-up

Incentives

$10 – Laboratory testing

$15 – Returning for results and post-test counseling

within 4 weeks

Participants recruited between February and August 2012

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• The protocol and informed consent form were approved by the UBC/Providence Health Care Research Ethics Board

•The study is supported by the National Institute on Drug Abuse and the CIHR Canadian HIV Trials Network

–registered on ClinicalTrials.gov (NCT01526421)

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Statistical analysis• Chi-square test or Fisher’s exact test were used for

analysis of categorical variables• Wilcoxon rank-sum test was used for continuous

variables• A multivariate logistic regression model considering

possible confounders was used to estimate the probability of completing testing and returning for test results, with the variable of interest being receipt of incentives

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Baseline DemographicsVariable Control Group

(N=150)Incentive Group

(N=151)p value

Median age (IQR), years 43 (36-50) 45 (36-51) 0.604

Male gender, N (%) 103 (68.7%) 98 (64.9%) 0.488

Ethnic group, N (%)CaucasianAboriginalBlackAsianHispanic/Latino Other

82 (54.7%)58 (38.7%)

4 (2.7%)1 (0.7%)0 (0%)

2 (3.3%)

85 (56.3%)62 (41.1%)

3 (2.0%)0 (0%)

1 (0.7%)0 (0%)

0.628

Housing , N (%)HomelessUnstable (SRO)

23 (15.3%)60 (40.0%)

32 (21.2%)90 (59.6%)

0.983

IQR, Interquartile rangeSRO, Single-room occupancy hotel

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Baseline characteristics cont’dVariable Control Group

(N=150)Incentive Group

(N=151)p value

Type of drug, N (%)Heroin onlyCocaine onlyMethamphetamine onlyMultiple drugsNot specified

21 (14%)15 (10%)

8 (5%)

39 (26%)67 (44%)

28 (18.5%)28 (18.5%)15 (10%)

70 (46%)10 (7%)

<0.001

Frequency of use, N (%)Not specifiedOccasionallyRegularlyDaily

67 (44%)15 (10%)23 (15%)45 (30%)

10 (7%)30 (20%)43 (28%)68 (45%)

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HIV Testing and post-test counseling

P<0.001 P<0.001

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Factors associated with HIV Screening completion

Variable Odds Ratio (95% CI) p value

Randomized study armControl armIncentives arm

1.0031.83 (15.63, 64.80)

<0.001

Adjusted for age, gender, ethnicity, housing and frequency of drug useCI, Confidence interval

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HIV eligibility screening among known HIV+ cases

Variable Control Group (N=17) Incentive Group (N=13) p value

Completed lab testingN (%)

9 (52.9%) 13 (100%) 0.004

Returned for post-test counselingN (%)

5 (29.4%) 12 (92.3%) 0.001

CD4 count (cells/mm3) Median (IQR)

440 (290-680) 315(120-535) 0.881

HIV RNA (copies/mL) Median (IQR)

19,175 (1,353-34,972) 19,657 (239-48,458) 0.170

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Hepatitis C Screening• 122 individuals were found to be HCV

Antibody positive– 98 in incentives arm (64% tested), 24 in control

arm (50% tested) p. 0.06

• Of 122 individuals, only 71 (58%) had self-reported known HCV+ status at study entry

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Limitations

• Single centre study• Relatively circumscribed drug-using

population in the DTES neighbourhood of Vancouver– No new HIV cases identified

• Drug use patterns missing for subjects, notably in the control arm

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Future Directions

• Phase 2 of this study is underway to examine the effect of incentives on increasing engagement and retention in ART programs– Evaluation of incentive-linked testing in a non-

randomized fashion– Incentives linked to clinic visits and achieving

undetectable plasma viral load

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Conclusion

• The use of modest financial incentives increased rates of HIV testing and post-test follow-up among drug users

• Significantly more individuals with known HIV but no engagement in care completed laboratory studies to evaluate ART eligibility

• Incentive-linked testing may be a strategy for engaging hard-to-reach populations such as drug users in HIV testing interventions as a component of “Treatment as Prevention” programs– Cost-effectiveness of this incentives strategy must still be

determined

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Acknowledgement

We would like to thank all participants and study personnel

This study was funded by National Institutes of Health – National Institute on Drug Abuse