Alcohol Policies and Motor Vehicle Crash Deaths Involving Blood Alcohol Concentrations Below 0.08

Introduction: Motor vehicle crashes are a leading cause of injury death in the U.S. Restrictive alcohol policies protect against crashes involving alcohol above the legal blood alcohol concentration of 0.08%. Characteristics of motor vehicle crash fatalities involving blood alcohol concentrations below the limit and their relationships to alcohol control policies have not been well characterized.

Methods: Motor vehicle crash fatality data and crash and decedent characteristics from 2000 to 2015 came from the Fatality Analysis Reporting System and were analyzed in 2018-2019. Alcohol Policy Scale scores characterized alcohol policy environments by state-year. Generalized estimating equation alternating logistic regression models assessed these scores and the odds that a fatality involved alcohol below the legal threshold.

Results: Of 612,030 motor vehicle crash fatalities, 223,471 (37%) died in alcohol-involved crashes, of which 33,965 (15% of alcohol-involved fatalities or 6% of all fatalities) had a blood alcohol concentration <0.08%. A 10 percentage point increase in Alcohol Policy Scale score, approximating the interquartile range among states, was associated with reduced odds of fatalities involving alcohol <0.08% vs 0.00% (AOR=0.91, 95% CI=0.89, 0.93). These findings held across multiple subgroup analyses by decedent and crash characteristics. Similar results were found for odds of alcohol involvement <0.05% vs 0.00% (AOR=0.90, 95% CI=0.88, 0.93), and ≥0.05% but <0.08% vs <0.05% (AOR=0.93, 95% CI=0.89, 0.96).

Conclusions: The number of lower blood alcohol concentration fatalities is substantial. States with more restrictive alcohol policies tend to have reduced odds of lower blood alcohol concentration motor vehicle crashes than states with weaker policies.