Factors associated with concurrent Heroin use among patients on Methadone maintenance treatment in Vietnam from 2008 to 2013 Hoang Nam Thai MD, MPH – CDC/DGHT Vietnam

Background Heroin injection and HIV epidemic in Vietnam Heroin addiction and social consequences Methadone maintenance treatment (MMT) started in Vietnam in 2008 Expanded to 54 provinces: 203 sites with over 38,000 patients by Sept 2015 One cohort study in HCMC and Hai Phong at pilot phase No national scale evaluation implemented Evidence at national scale needed for advocacy purpose Clinical data available and collected routinely

Objectives To estimate proportion of patients who use Heroin concurrently with MMT, and Identify factors associated with continued Heroin use among patients on MMT

Methods Study design: Retrospective abstraction of data from a nationally representative sample of MMT patient records Abstraction by intervals: Baseline; 0-3 months, 3-6 months, 6 – 12 months, 12 – 24 months Subjects and sampling: Medical records of patients who initiated MMT at least 24 months before Jan 1, MMT sites in 11 provinces met selection criteria 10 sites (from 7 provinces) selected by PPS approach 50 patient records chosen from each selected site by systematic random approach

Methods (cont’) Variables: Use Heroin concurrently with MMT Used Heroin at any day in 30 days prior to the end date of month 3, 6, 12 or 24 Used Heroin if patient self-reported with clinicians and/or had urine test positive Independent variables: Demographic characteristics History of Heroin use Treatment process: Services provided and methadone dose Clinical characters: HIV infection, either on ART or not

Methods (cont’) Data analysis Descriptive analysis: used means, SE, range of values, frequencies, absolute number, proportions and Factors associated with Heroin use: Multivariable Logistic Regression

Study population Baseline 500 patient-records 3 months 497 patient-records 6 months 492 patient-records 12 months 473 patient-records 24 months 441 patient-records 2 Arrested 1 Mandatory detoxification 1 Arrested 4 No reason or other reasons 1 Died (HIV+) 5 Arrested 1 Mandatory detoxification 2 Voluntarily stopped 10 No reason or other reasons 4 Died (2 HIV+) 8 Arrested 1 Mandatory detoxification 7 Voluntarily stopped 12 No reason or other reasons

Baseline socio-demographic characteristics CharacteristicsnProportion (95%CI) Male ( ) Age (mean: 33.3; SE: 0.6) < – 39 ≥ (26.4 – 42.8) 45.2 (39.8 – 50.6) 20.2 (13.6 – 26.8) Education level Junior High school or lower High school or higher (45.5 – 67.2) 43.7 (32.8 – 54.5) Marital status: Single (not ever married) Married or live with partner as couple Divorce or separation (27.9 – 45.7) 49.6 (38.5 – 61.1) 9.4 (4.1 – 14.6) Unemployment (35.8 – 51.4) Gain family emotional and/or financial support (88.5 – 97.1)

History of opiates use at baseline VariablesnMean (SE)Proportion95% CI Number of years using opiates (0.4) 9.36 – Number of years injecting opiates (0.3) 6.48 – 8.03 Frequency of use at registration times per day 4 times or more per day – – 36.3 Route of use: Injection – 99.2 Ever shared needles & syringes – 13.7 Overdose history – 24.2

Co-morbidities at baseline ComorbiditiesnProportion95% CI HIV infection – 75.3 HBV infection – 20.5 HCV infection – 56.3 HIV & HCV co-infection – 23.5 HIV & HBV co-infection – 7.3 HBV & HCV co-infection – 9.2 HIV, HBV & HCV co-infection – 4.3 TB history – 15.3 Mental health disorder history – 8.4

Higher means of methadone doses among patients on ART

Missed dose-days 3 months (n=500; %) 6 months (n=493; %) 12 months (n=437; %) 24 months (n=411; %) Any missed dose-day 25 (5.0)81 (16.4)118 (27.0)144 (35.0) 1 – 3 dose-days in a row 19 (3.8)70 (14.2)102 (23.3)127 (30.9) 4 – 5 dose-days in a row 4 (0.8)6 (1.2)9 (2.1)11 (2.7) 6 or more dose-days in a row 2 (0.4)4 (0.8)13 (3.0)18 (4.4)

Proportion of concurrent Heroin use reduce overtime

Factors associated with concurrent Heroin use at month 12 FactorsN=338 n (%) Adjusted OR (95%CI) Used Heroin < 15 years at baseline52 (16.1) 3.65 (1.30 – 10.21) Used Heroin ≤ 3 times a day at baseline 43 (16.3) 2.13 (1.15 – 3.91) Methadone dose at month 12 < 60mg per day 60 – 100mg per day > 100mg per day 25 (21.6) 9 (5.8) 22 (19.6) (0.04 – 0.99) 1.05 (0.40 – 2.75) HIV negative or unknown HIV infection, not on ART HIV infection, on ART 35 (14.6) 8 (23.5) 10 (16.9) (1.04 – 4.22) 1.19 (0.38 – 3.76) Missed any methadone dose in 0-3 months 8 (40.0)4.90 (3.20 – 7.50) Missed any methadone dose in 3-6 months 15 (23.1)1.72 (1.03 – 2.87)

Factors associated with concurrent Heroin use at month 24 FactorsN=276, n, % Adjusted OR (95% CI) Gained family support Yes No 31 (13.1) 5 (28.6) ( ) Methadone dose at month 24 < 60 mg per day 60 – 100 mg per day > 100 mg per day 12 (10.3) 15 (13.5) 17 (20.7) (0.48 – 4.07) 1.91 (0.72 – 5.10) HIV infection status Negative or unknown HIV infection, not on ART HIV infection, on ART 17 (8.9) 5 (21.7) 16 (25.4) ( ) 2.75 ( )

Discussion Proportion of MMT patients use Heroin concurrently reduced overtime and maintain at low level after one year Factors associated with concurrent Heroin use were differed between month 12 and 24 suggesting different strategies to manage at different treatment phases Missing dose and methadone dosing seem to be more important in early phase HIV infection, either on ART or not seem to be more important in later phase

Discussion (cont.) Association between early missing doses and later concurrent Heroin use suggest targeted interventions for this group Methadone dose of lower than 60mg/day related to Heroin use concurrently consolidate recommendation from WHO on minimum effective dose Specific intervention strategies for HIV infection patients

Strengths and weaknesses Strengths: Utilization of routinely collected data that available every where Simple process: Site staff can abstract and use abstracted data by themselves Low cost Weaknesses: Quality of information depends on quality of documentation of information in medical records Missing information, even information about interested outcome Need some basic clinical knowledge and training before abstracting data Lack of information from drop-out cases

Acknowledge Colleagues from CDC Atlanta and Vietnam Colleagues from VAAC/MOH Selected MMT clinics