Primary and secondary prevention of drink driving by the use of alcolock device and program: Swedish experiences

To prevent drinking and driving, alcolock (or alcohol-interlock) devices and programs were introduced in Sweden in 1999. Two types of prevention programs were begun. A primary prevention strategy was initiated to prevent alcohol impaired driving by individuals not pre-selected for having prior DWI offences. This approach was first applied as a pilot project in three commercial transport companies (buses, trucks, taxis). Also a secondary prevention trial was begun as a voluntary 2-year program for DWI offenders involving strict medical requirements, including counseling and regular checkups by a medical doctor. The program did not require a prior period of hard suspension and focused on changing alcohol use habits. Alcolocks in commercial vehicles have been well accepted by professional drivers, their employers, and their passengers, and the number of vehicles with alcolocks as a primary prevention measure is rapidly growing in Sweden. Three of 1000 starts in the primary prevention program were blocked by the alcolock after measuring a BAC higher than the legal limit and lock point of 0.02% (20mg/dl). Only 11% of eligible DWI offenders took part in the voluntary, secondary prevention program. Of these, 60% had diagnoses of alcohol dependence or abuse. During the program, alcohol consumption generally decreased significantly as measured through five biological alcohol markers, and the rate of DWI recidivism fell sharply from a yearly rate of approximately 5% to almost 0. These effects on DWI recidivism are paralleled by reduced rates of police-reported traffic accidents involving injuries and hospital admissions due to road accidents. Successful completion of the program appears to have lasting effects (even 2.5 years later) in terms of far lower rates of DWI recidivism and maybe also lower crash rates. On the other hand those being dismissed from the program appear to rapidly return to previous behaviour. Hard suspension seems almost to have an adverse effect on DWI recidivism, but crashes resulting in injuries may be reduced during revocation.