ALCOHOL BIOSENSORS: RESEARCH BACKGROUND AND CLINICAL APPLICATIONS NANCY BARNETT CENTER FOR ALCOHOL AND ADDICTION STUDIES DEPARTMENT OF BEHAVIORAL AND SOCIAL SCIENCES SCHOOL OF PUBLIC HEALTH BROWN UNIVERSITY No conflicts of interest
TRANSDERMAL DETECTION OF ALCOHOL A small concentration of consumed alcohol is excreted through the sweat glands (Swift, 1993; 2003) Sensors can measure this concentration on the surface of the skin
TRANSDERMAL DETECTION OF ALCOHOL Two devices currently commercially available: Secure Continuous Remote Alcohol Monitoring (SCRAM) Transdermal Alcohol Detection (TAD)
SCRAM TM Take readings regularly - store readings for later retrieval Locked on cannot be removed Temperature and contact sensors Water resistant but not waterproof TAD TM
TAC GRAPH (SCRAM) peaks at 3 AM TAC curve starts about 8 PM returns to.000 at 9 AM
OVERVIEW Evidence for validity of alcohol biosensors Review adoption and efficacy in criminal justice Acceptability Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Suggestions for uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
OVERVIEW Evidence for validity of alcohol biosensors Review adoption and efficacy in criminal justice Acceptability Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Suggestions for uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
EVALUATION OF TRANSDERMAL SENSORS In lab studies: Peak TAC highly correlated with peak BrAC (Swift et al., 1992; Sakai et al., 2006) Total area under the TAC and BrAC curves (reflecting volume consumed) were highly correlated (Swift et al., 1992; Sakai et al., 2006) In field studies: Self-reported drinking correlated with TAC area under the curve (Barnett et al., 2011; Swift et al., 2004)
OVERVIEW Evidence for validity of alcohol biosensors Review adoption and efficacy in criminal justice Acceptability Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Suggestions for uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
USE AND EFFICACY WITH ALCOHOL OFFENDERS SCRAM being used by agencies in 49 states; has monitored more than 250,000 offenders From a group of 9,100 offenders who were monitored using the SCRAM device from 2004 to 2009, 75% were considered compliant (no alcohol use or tampering occurred) (McKnight et al., 2012) DWI repeat offenders who wore the SCRAM for 90 days or more had lower recidivism than matched DWI offenders (Flango & Cheesman, 2009) Offenders have reported that wearing bracelet helped them maintain sobriety that they could not have otherwise achieved (Marques & McKnight, 2007) But, no controlled trials with offenders
OVERVIEW Evidence for validity of alcohol biosensors Review adoption and efficacy in criminal justice Acceptability Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Suggestions for uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
REPORTS FROM ALCOHOL OFFENDERS Positive Enforcement of abstinence led to benefits of not drinking: Sharper mind, better sleep, better work performance, and better relations with family Provided proof to the probation authority that the offenders claims of abstinence were genuine Reduces peer pressure associated with drinking (offenders can blame the decision not to drink on the bracelet) A resigned sense of gratitude that the alternative to SCRAM, jail, was worse than having to endure the discomfort Negative Physical discomfort Cost of SCRAM ($5-12 per day) Public embarrassment or embarrassment with close acquaintances Some equipment-related problems.
WHAT DOES IT FEEL LIKE? 3 or 4 week trial: Of 48 volunteer participants, 60.4% reported marks on skin from bracelet. Less common but more severe included raw skin, blister, bruise, heat rash. One person was removed because of allergy to nickel. Scale: 1 = comfortable 10 = uncomfortable Physical discomfort (M = 6.1) Neutral Started uncomfortable but gradually got used to it Did not notice the bracelet after the first couple of days My bracelet fit well, it was a little loose which bothered me a little but I got use to it Negative Too heavy Much larger than I expected Rides on your ankle bone From Barnett et al. (2011) and Barnett et al. (in preparation)
MODERATE SOCIAL DISCOMFORT Scale: 1 = comfortable 10 = uncomfortable Social discomfort (M = 4.8) Neutral Didn t feel uncomfortable at all I was asked a lot of questions but I didn't mind answering I discussed it with people I know so they would be aware of it & not have to speculate if they caught a glimpse of it unexpectedly Negative People often made comments implying that I was in legal trouble. I felt like I had to cover it up and explain it all the time. Boss was a bit apprehensive ; My wife didn t like me to be seen with it People stared at times Some study withdrawal due to negative attention From Barnett et al. (2011) and Barnett et al. (in preparation)
OVERVIEW Evidence for validity of alcohol biosensors Review adoption and efficacy in criminal justice Acceptability Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Suggestions for uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
WITHIN-SUBJECTS A/B DESIGN (N = 13) Heavy drinking subjects willing to reduce their alcohol use Week 1: Baseline week; no contingencies for alcohol use Weeks 2-3: Escalating payments of $5 - $17 per day for no reported or detected drinking Reinforcer report available on project website Barnett et al., 2011
PERCENT OF SAMPLE WITH NO ALCOHOL DETECTED BY DAY 79% reduction in volume of alcohol consumed 69% of subjects reduced alcohol use below NIAAA recommended limits
BETWEEN SUBJECTS (N = 30) One baseline week, 3 weeks of contingent reinforcement for no detected drinking vs. yoked noncontingent reinforcement Barnett et al. (in preparation)
RCT: CONTINGENT VS. NONCONTINGENT 40% of the Contingent group had more than a week abstinent; 0 in Noncontingent p <.05
CASE EXAMPLE # 1
CASE EXAMPLE #2
OVERVIEW Describe alcohol biosensors validity, reliability, and acceptability Review adoption and efficacy in criminal justice Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Suggestions for uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
COMBINE MONITORING WITH TREATMENT IN CRIMINAL JUSTICE Case studies with the largest systems using SCRAM (McKnight et al., 2012) Many offenders are mandated to treatment in addition to monitoring Most of the monitoring programs do not interface with treatment Providers are typically provided no information from the monitoring entity Some suggest that monitoring is not likely to create long term success unless used in combination with treatment (Flango & Cheesman, 2009; Gable & Gable, 2007)
CLINICAL APPLICATIONS: INTERVENTIONS FOR ALCOHOL ABUSE/DEPENDENCE Offender populations Efficacy, best practices, integration of program with treatment Evaluate lower thresholds for using monitoring to reduce prison crowding Voluntary clinical populations Participants reported new levels of insights about their drinking, and frustration about not being able to reduce as they liked these are clinical opportunities CM + complementary treatment Different response trajectories potential for detecting different treatment needs early Monitoring and intervening in real time Cost effectiveness
CLINICAL APPLICATIONS: MEDICAL POPULATIONS (E.G., SURGICAL PATIENTS, HIV+, DIABETES) Alcohol influences medication adherence, disease progression for many diseases, affects nutrition, recovery from surgery Provide more precise measures of alcohol use patterns and volume We can objectively verify continuous and consistent reductions in alcohol use; what might be the effect on medication adherence, understanding of disease processes, treatment efficacy? Integrate with other wearable or passive sensors
OVERVIEW Describe alcohol biosensors validity, reliability, and acceptability Review adoption and efficacy in criminal justice Efficacy of contingent reinforcers for reducing alcohol use utilizing an alcohol sensor Offer suggestions for other clinical uses of sensor technology Discuss challenges to adoption of sensors in clinical settings
CHALLENGES/SOLUTIONS Challenges Acceptance by clients Solutions Miniaturization and redesign appearance Acceptance by providers Cost Data management Need early adopters; creative thinking about best ways to use data within treatment and to reduce reactance with clients Reducing Easy to use tools available
SUMMARY Similar to other body sensors used to assess disease processes, there is a high potential for using alcohol sensors to augment alcohol assessment and treatment Use with alcohol offenders is growing, with various program types being developed, with lower thresholds for use Efficacy found in both alcohol offender and volunteer samples recidivism lowered and behavior change verified More controlled research is needed Devices are uncomfortable and embarrassing design modifications would make utility greater in voluntary settings (alcohol treatment and medical intervention)
ACKNOWLEDGMENTS NIAAA R21AA27767, R21AA020943 Collaborators Jennifer Tidey Robert Swift James Murphy Suzanne Colby NIAAA T-32 Postdoctoral Fellows Nadine Mastroleo Lindsay Orchowski John Hustad Staff Tiffany Glynn Polly Gobin Michelle Loxley Elizabeth Meade Cheryl Eaton Timothy Souza
THANK YOU Nancy_Barnett@Brown.edu
SCRAM DATA