Risk Factors for Falling Asleep at the Wheel

Drowsy driving tied to binge drinking and lack of sleep

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Falling asleep behind the wheel is a dangerous situation. Preventing such situations requires knowing what can lead to drowsy driving — a topic that researchers recently explored.

A new study looked at survey results measuring a number of behaviors and risk factors from adults in several US states.

The researchers found links between drowsy driving and several other behaviors, including sleeping less, binge drinking and not wearing a seatbelt.

"Call a taxi if you're not in a safe state of mind to drive."

This study was led by Anne G. Wheaton, PhD, of the Centers for Disease Control and Prevention's (CDC) National Center for Chronic Disease Prevention and Health Promotion.

According to Dr. Wheaton and colleagues, drowsy driving contributes to many car accidents and deaths each year in the US, but little is known about how drowsy driving is tied to other risk factors and behaviors.

To explore this, Dr. Wheaton and team used data from the 2011 to 2012 Behavioral Risk Factor Surveillance System phone surveys. These surveys included data from 92,102 adult respondents in 10 US states and Puerto Rico.

Participants were asked, “During the past 30 days, have you ever nodded off or fallen asleep, even just for a brief moment, while driving?” Those who said yes were considered as having experienced drowsy driving.

After analyzing the data, the researchers found that 4 percent of participants reported falling asleep while driving at some point during the previous month.

Younger adults were more likely to report drowsy driving than older adults. More specifically, 5.9 percent of participants between the ages of 18 and 24 reported drowsy driving, versus 1.8 percent of participants aged 65 or older.

Dr. Wheaton and team also found that men were more likely to report drowsy driving than women — 5.0 percent versus 3.0 percent.

When looking at drowsy driving and other behaviors, some associations were found. Those who reported sleeping five hours or less each day were more likely to report drowsy driving (9.1 percent) than those who slept six hours (5.2 percent) or seven hours or more (2.7 percent).

Binge drinkers — defined as men who reported having five or more alcoholic drinks and women who reported having four or more drinks during a single occasion in the previous month — were more likely to report drowsy driving (5.2 percent) than non-binge drinkers (3.7 percent) and those who did not drink at all (3.6 percent).

The researchers also found that those who reported sometimes, seldom or never wearing a seatbelt were more likely to report drowsy driving (6.6 percent) than those who reported always or almost always wearing a seatbelt (3.9 percent).

"Interventions designed to reduce binge drinking and alcohol-impaired driving, to increase enforcement of seatbelt use, and to encourage adequate sleep and seeking treatment for sleep disorders might contribute to reductions in drowsy driving crashes and related injuries," wrote Dr. Wheaton and team.

This study only looked at adults from certain states and the data were self-reported by participants. Further research is needed to confirm these findings.

The study was published online on July 3 in CDC's Morbidity and Mortality Weekly Report. No conflicts of interest were reported.

Review Date: 
July 3, 2014
Last Updated:
July 7, 2014