Acute and Residual Effects of Caffeinated Beer

Phase 1

Completed

Conditions: Neurobehavioral Manifestations
Drug Related Sleep Disturbance
Alcohol Intoxication

Interventions: Drug: Caffeinated Alcoholic Beer
Other: Non-Caffeinated Alcoholic Beer
Drug: Caffeinated Non-Alcoholic Beer
Other: Non-Caffeinated, Non-Alcoholic Beer

Registration Number: NCT00515294

Lead Sponsor: Boston University

Brief Summary: The aim of this study is to develop information about the acute and residual effects of a new product being targeted to young adults. Using a double placebo-controlled 2 X 2 factorial model study design, we will compare the acute and residual effects on driving impairment of caffeinated alcohol, non-caffeinated alcohol, caffeinated placebo, and non-caffeinated placebo. Under the alcohol conditions, participants will receive sufficient alcoholic beverage to attain a blood alcohol concentration (BAC) of .12 g%. Participants will be 144 undergraduate and graduate students, and recent college graduates.

Detailed Description: Caffeinated alcoholic beverages target young adults with the promise that the caffeine will counteract the sedating effects of alcohol and thus let the consumer remain alert and active longer, while continuing to drink. It is likely that in the minds of some young people, this promise also translates into the idea that mixing caffeine with alcohol allows one to drive more safely than would be possible after having consumed an equivalent amount of non-caffeinated alcoholic beverage. These are dangerous assumptions because (1) alertness may not indicate the absence of impairment under intoxication and (2) next-day impairment from the residual effects of heavy drinking may be exacerbated by mixing caffeine and alcohol. We will compare the acute and residual effects of caffeinated and non-caffeinated beer in terms of a highly relevant outcome - the ability to drive safely.

The long-term objectives of this program of research are to investigate factors that predict or contribute to performance decrements after alcohol ingestion, with a focus on behaviors most relevant to public health, such as driving. The primary specific aims of the proposed work are:

AIM 1: To compare the acute effects of caffeinated alcohol, non-caffeinated alcohol, caffeinated placebo, and non-caffeinated placebo on driving-related impairment, as measured by performance on a driving simulator and the Psychomotor Vigilance Test (PVT), a test of sustained attention/reaction time. We hypothesize that caffeinated beverage will result in less impaired simulated driving ability and better PVT performance acutely, compared to non-caffeinated beverage, but that performance on these measures following both caffeinated and non-caffeinated beverage be impaired relative to placebo beverages.

AIM 2: To compare the residual effects of caffeinated alcohol, non-caffeinated alcohol, caffeinated placebo, and non-caffeinated placebo on next-day driving-related impairment, as measured by a driving simulator and the PVT. We hypothesize that caffeinated beverage will result in greater impairment in next-day simulated driving and attention/reaction time, relative to non-caffeinated beverage, and that performance following both caffeinated and non-caffeinated alcoholic beverages will be impaired relative to corresponding placebo beverages.

AIM 3: To compare the acute effects of caffeinated alcohol, non-caffeinated alcohol, caffeinated placebo, and non-caffeinated placebo on self-rated ability to drive, as measured by a self assessment of ability-to-drive questionnaire, and estimate of blood alcohol concentration (BAC). We hypothesize that caffeinated alcoholic beverages will result in greater confidence in ability to drive and lower estimates of BAC, compared to non-caffeinated alcoholic beverages, but that for both alcoholic beverages, confidence in driving ability will be lower and estimates of BAC will be greater, relative to placebos.

AIM 4: To compare the residual effects of caffeinated alcohol, non-caffeinated alcohol, caffeinated placebo, and non-caffeinated placebo on self-rated ability to drive. We hypothesize that caffeinated alcoholic beverage will result in lower confidence in ability to drive and higher estimates of BAC, compared to non-caffeinated alcoholic beverage, but that for both alcoholic beverages, confidence in driving ability will be lower and estimates of BAC will be greater, relative to placebo.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 154

Inclusion Criteria

College students, graduate students, or recent graduates
Between the ages of 21 and 30 years inclusive (as verified by valid drivers license)
Who, if a student, reports good academic standing
Have not been diagnosed with a sleep disorder
Are not daily smokers
At least occasionally in the past month, consume five drinks (for men) or more (four or more if female [based on Flannery et al 2002]) during a single drinking episode
Have a valid drivers license, so as to include only people who know how to drive.

Exclusion Criteria

Scores of 5 or more on a screening measure for alcoholism (the short version of the Michigan Alcohol Screening Test [SMAST])
A history of counseling or treatment for chronic substance abuse by self-report
Daily smoker (to mitigate confounding of caffeine by nicotine withdrawal, or acute nicotine administration, smokers will be excluded from participation)
Current use of medications that affect the sleep/wake cycle or daytime alertness or that are contraindicated for alcohol
Presence of a health condition that contraindicates alcohol
Diagnosis of a sleep disorder (sleep apnea, narcolepsy, periodic limb movement, restless legs syndrome, circadian rhythm disorder, and insomnia)
Use of recreational drugs (e.g., marijuana) while participating in the study
Working overnight shifts
Female and pregnant, nursing, or not using reliable birth control
Participants who have traveled across two or more time zones in the last month will be rescheduled for later participation (minimum of 1 month from time-zone travel)
On average consume greater than 4 cups of coffee per day (>400 mg/day)
Participants who report ever getting motion sick during screening or become motion sick after practicing on the driving simulator during Session 1.
Weigh more than 230 Lbs.

Study & Design

Study Type: INTERVENTIONAL

Study Design: FACTORIAL

Arm && Interventions

Group	Intervention	Description
1Caffeinated Alcoholic Beer	Caffeinated Alcoholic Beer	Caffeinated Alcoholic beer
2Non-Caffeinated Alcoholic Beer	Non-Caffeinated Alcoholic Beer	Non-Caffeinated Alcoholic beer
3Caffeinated Non-Alcoholic Beer	Caffeinated Non-Alcoholic Beer	Caffeinated Non-Alcoholic Beer
4Non-Caffeinated, Non-Alcoholic Beer	Non-Caffeinated, Non-Alcoholic Beer	Non-Caffeinated, Non-Alcoholic Beer

Primary Outcome Measures

Name	Time	Method
Lane Position Deviation	30 minutes post dosing	The reported lane position deviation indicates the position of the car relative to the center line in feet in the driver simulator. A deviation of 0 indicates no deviation from the center line (the car is positioned farthest from the road edge). Negative numbers indicate deviations to the right of the center line with the car positioned within the lane closer to the road edge. Positive numbers indicate deviations to the left of the center line with the car positioned in the lane of oncoming traffic closer to the road edge

Secondary Outcome Measures

Name	Time	Method
Psycho-motor Vigilance Test (PVT)	30 minutes post dosing	Participants completed 10 test trials to assess their psycho-motor response using a hand held box that randomly starts a scroll of numbers in milliseconds and as soon as it starts to scroll the participant needs to press a button to stop the scrolling. The mean and standard deviations for the 10 tests were calculated as a single outcome score for each study arm. Response times were measured in milliseconds. The lower the number of milliseconds the faster the response to the random stimuli.