Abstract
Background and aimsThe municipality of Amsterdam implemented a new alcohol policy allowing alcohol outlets in two of the five nightlife areas to extend their closing times from 1 April 2009 onwards. We investigated how levels and trends of alcohol-related injuries changed after implementation of this alcohol policy, by comparing areas with extended closing times to those without.DesignA controlled before-and-after evaluation to compare changes in alcohol-related injuries between intervention and control areas.SettingCentral district of Amsterdam, The Netherlands.ParticipantsAlcohol-related ambulance attendances for control and intervention areas between 1 April 2006 and 1 April 2009 (respectively, n=544 and n=499) and between 1 April 2009 and 1 April 2011 (respectively, n=357 and n=480).MeasurementsAlcohol-related injuries were defined as ambulance attendances for people who suffered from direct or indirect consequences of alcohol consumption. Injuries were counted per month in two intervention and three control nightlife areas. We used Poisson regression to assess changes in injuries.FindingsAfter 1 April 2009, intervention areas showed a larger change in the level of alcohol-related injuries than control areas [incidence rate ratio 1.34, 95% confidence interval (CI)=1.12, 1.61], but trends remained stable in all areas. This increase was only statistically significant for the following subgroups: 2-5.59 am, weekend days, men, individuals aged 25 to 34 years, and people transported to a hospital. However, the increase did not differ between subgroups with statistical significance.ConclusionsA 1-hour extension of alcohol outlet closing times in some of Amsterdam's nightlife areas was associated with 34% more alcohol-related injuries.