Transcript Fourth year research proposal

Fourth year research proposal
The effects of consuming alcohol mixed with energy drinks
(AmED) on risk-taking
Holly Bromfield
Supervisors: Assoc. Prof Raimondo
Bruno and Dr Amy Peacock
EDs are commonly mixed with alcohol to reduce tiredness whilst drinking so that users
can drink for longer.
Mixing ED with alcohol typically does nothing to improve performance (Peacock et al.,
2014)
But, may increase stimulation, causing misinterpretation of level of intoxication
(Peacock, Bruno, Martin & Carr, 2013)
Misinterpretation of intoxication may lead to an increase in risk-taking.
Rationale
Does consuming AmED increase risk-taking?
Self-report retrospective survey studies
•Between-subjects: AmED users reported greater
risk-taking relative to other alcohol drinkers (Peacock,
Pennay, Droste, Bruno & Lubman, 2014)
•Are AmED drinkers more risky?
•Within-subjects: Lower risk taking in AmED
drinking sessions relative to alcohol only session
(Peacock, Pennay, Droste, Bruno & Lubman, 2014)
•Environment?
•Frequency of use?
Measures of risk-taking
•Simulated driving task:
•Non-significant interactive effect of
alcohol and ED (p = .508) (Lubman et
al., 2013).
Balloon Analogue Risk Task (BART):
•Significant main effect of ED, g =
0.28, p = 0.047
•No interactive effects of alcohol and
ED. (Peacock, Bruno, Martin & Carr,
2013).
Rationale
Automatic Balloon Analogue Risk Task (ABART)
•Measures risk-taking
•Includes all trials
•Outcome measure: Pumps entered to blow
up virtual balloon
Rationale
Determination Test component of the Fitness to
Drive Standard test battery (Schuhfried GmBH,
2012).
•Measures stress, reactive tolerance
•Visual, auditory and
other stimuli
•Outcome measures:
Number of correct
responses and reaction
time.
Rationale
Real world drinking
•ED doses of 750ml
•Pre-drinking
•Drinking throughout the
night.
Recommended drinking
•Maximum of 500ml ED in 24 hours
•Maximum of 4 std. alcoholic drinks
on one occasion
Limitations of current research
•ED doses limited to 500ml – 160mg of caffeine
•Bolus administration
Aims
•To test the effect of consuming AmED on
risk-taking by comparing individual’s
performance on two measures of risk
behaviour relative to their performance
when they consume alcohol only.
•Replicating real-world doses e.g., 2.5 EDs
and 5 standard alcoholic beverages.
0
30
Number of correct
Responses (less correct
responses = increased risk)
Number of pumps
(more pumps =
increased risk)
AmED
Alcohol
60
0
30
Reaction Time (faster
RT = increased risk)
Hypotheses
90
60
Time
Alcohol
AmED
0
90
30
Time
Alcohol
AmED
60
Time
90
Design
6 (Time point) by 2 (Condition) within-subjects,
double blind, placebo controlled
Independent variable:
•Time point: Baseline, 15 minutes post dose 1, 2,
3 & 4, and again at 45 minutes post dose 4
•Condition: AmED and Alcohol only
Dependent variables:
•number of pumps
•number of correct responses
•reaction time
Participants
•N = 30 (15 males, 15 females)
•Age range = 18- 30
•Inclusion criteria:
•completion of Year 12
• have consumed 1 to 30 250ml ED in past month
• ≥ 5 standard alcoholic drinks on one occasion in past month
•have consumed 4-28 caffeinated beverages in the preceding week
• normal sleep patterns
•normal or corrected-to-normal vision.
•Exclusion criteria:
•current significant medical or neurological disorder
•pregnant or breastfeeding
•history of alcohol use at harmful levels Audit>16
•illicit drug use in preceding six months
•current use of prescription medication
•significantly elevated psychological distress Kessler-10 >25
•low pre-morbid intellectual functioning WTAR <85
Materials
Primary Measures
•Automatic BART
•DRIVESTA - Determination Test
Covariates
•The Attitudes to Driving Violations Scale
•Impulsivity scale - I7 Impulsiveness Questionnaire
Procedure
•1 x 60 minute familiarisation session
•Participants must abstain from the following:
•eating for 4 hours (except for consuming a
small meal 60 minutes before each session)
•caffeine for 8 hours and alcohol for 24 hours.
•illicit drugs and prescription medications for
the duration of participation
Dosing Schedule
Breath Alcohol Content (BrAC)
.10
.08
.05
0
0
30
60
Time (minutes)
90
120
Procedure
Dose ingredients:
•Vodka, (37.5% alcohol/volume
Smirnoff Red Label®,
•No.21)
•Red Bull each 250ml serve contains:
80mg caffeine
•Sugar syrup English-toffee and
Black Cherry
Procedure
Administration
•Standardized across participants/sessions
•Doses must be consumed within 10 minutes
(split into 2 equal doses)
•BrAC taken every 10 minutes post
consumption
Procedure
Releasing participants
Participants will be able to wait in a separate
room whilst they sober up. Once registering
two consecutive BrAC readings of 0.03% or
lower within a 15 minute period participants
will be free to leave.
Analysis
Power Analysis
•30 participants are required to achieve 80%
power to identify a moderate magnitude effect
of g=0.5 for the breakdown analyses
Data Analysis
•A 6 (Time) x 2 (Condition) mixed models for
repeated measures analysis will be used.
•Covariates will also be included in the model
and systematically tested for influence.