Alcohol Use & Misuse 10/18/12

Gmel & Rehm (2003) take-home messages: part I correlation vs. causation ? heavy drinking & workplace productivity No clear effect of consumption on absenteeism Some effect on work performance and coming late/leaving early consider potential confounding variables. . . Reverse causality: Work conditions lead to stress, poor productivity and drinking to cope Developmental process: Under-education/training due to alcohol problems may lead to bad jobs which could lead to absenteeism and poor performance on the job 3rd variable explanation: psychopathology or poor achievement orientation may lead to BOTH drinking and poor work performance

Gmel & Rehm (2003) take-home messages: part II correlation vs. causation ? alcohol intoxication probably plays a causal role in many unintentional injuries MVA, falls, drowning, burns, hypothermia via cognitive and physical impairment due to BAC Potential confounding variables? 3rd variable explanations? Impulsivity, disinhibition, poor judgment/cognitive impairment

Alcohol & Driving 1/3 of traffic fatalities are alcohol-related (MMWR, 2011) 1.8% of people who drank in last month admit to driving after drinking 4 million adults = 112,116,00 events Significant impairment in driving simulators is seen at BACs > .02 Divided attention Eye movement and visual perception Reaction times In 2009, about 10,839 persons died in alcohol-related traffic crashes, which constituted 39.5 percent of the total traffic crash fatalities. The proportion of alcohol-related traffic fatalities varied across States, ranging from 25.5 percent (Utah) to 52.2 percent (Rhode Island). Risks increase with BAC.

The risk of having a fatal crash rises sharply with higher BACs, relative to drivers who have not been drinking Risks increase with BAC; measurable at .02, and rise steeply. Age also makes a difference: risks increase even faster among drivers under 21.

Risk factors associated with alcohol-impaired driving Men aged 21-34 account for ___ % of alcohol- impaired driving events 85% of episodes were reported by ___________ the rate of alcohol-related driving events was 4x higher among _____________________ People living in the __________ drove under the influence more than people living in other regions 32% Though they are only 11% of the population BINGE DRINKERS The 4.5% of adult population who binged 4+ in a month accounted for 55% of all alcohol-impaired driving episodes PERSONS WHO DON’T ALWAYS USE SEATBELTS This suggests a 3rd variable: what might be related to both drinking and driving and failure to use seatbelts? MIDWEST Midwest also associated with highest prevalence of binge drinking in US: 16.5%

Percentage distributions of BAC among alcohol-involved drivers, by age, United States, 2004. From Yi, Chen, & Williams (2006) NIAAA publication http://pubs.niaaa.nih.gov/publications/surveillance76/fars04.htm Young drivers ages 21 to 24 continued to have the highest proportion (39.1 percent) of alcohol involvement among drivers in all age groups. But NOTE that drivers under 21 tended to be involved in crashes at lower BACs. Perhaps a combination of inexperience with driving, inexperience with drinking, or incomplete brain development, but this is a major reason for the MLDA being raised to 21 ---> So , you might ask, is this an effective way to reduce alcohol-involved traffic accidents among youth??

Percent change in alcohol-related motor vehicle accidents with changes in MLDA YES From Shults et al (2001, AJPM) meta-analyses: This summarizes a bunch of studies and puts them on the same metric: how much accidents changed from before to after the change in MLDA; this line (at 0) represents no change - increase - decrease TOP: In 1975, last US state reduced MLDA from 20-18 (after Vietnam era) ==> increase in alcohol related crashes of 10% BOTTOM: After 1984, when Uniform Drinking Age Act was passed, drinking ages were effectively lifted in all 50 states to 21 ==> decrease of 16% But that was then, society and young adults have changed since then. . . We happen to have a recent example of what might happen -- on this one dimension -- if MLDA were to be brought down.

“Lowering the minimum purchase age for alcohol increased traffic crash injuries among 15-19 year olds in NZ” (Kypri et al., 2005) Journal of the American Public Health Association In 1999, NZ dropped the drinking age from 20-18. This gives us a recent test of what might happen if the US drinking age was lowered. For male and females, newly legal (18-19) youth, traffic crashes due to alcohol intoxication went up significantly. Trickle down effect: crashes also went up in the age bracket just below them (15-17) Keep in mind that traffic crashes account for HALF of all deaths in the 15-19 age range.

Are MLDA laws effective ? States with more laws on the books restricting alcohol use have lower youth drinking rates Enforcement of underage drinking laws predicts lower drinking rates Enforcement of the Legal Minimum Drinking Age in the United States Alexander C. Wagenaar, Mark Wolfson Journal of Public Health Policy, Vol. 15, No. 1 (Spring, 1994), pp. 37-53 rates of enforcement of the legal drinking age are very low; actions against outlets or adults providing alcohol to youth are particularly rare; penalties appear too lenient to deter providers of alcohol; and levels of enforcement of the drinking age vary significantly across states.

Framework for reducing alcohol-impaired driving Shults et al. (2001)