‘ Alcohol and Violence in the Emergency Room: A Regional Report from the WHO Collaborative Study on Alcohol and Injuries Guilherme Borges 1,2, Ricardo Orozco2, Mariana Cremonte3, Neliana Buzi Figlie4, Cheryl Cherpitel5, Vladimir Poznyak6, 1.Universidad Autónoma Metropolitana, Mexico City, Mexico 2.Instituto Nacional de Psiquiatría, Mexico City, Mexico 3. National University, Mar del Plata, Argentina 4.UNIAD - UNIFESP2, Sao Paulo, Brazil 5. Alcohol Research Group, Public Health Institute, Berkeley CA, USA 6. Department of Mental Health and Substance Dependence, WHO, Geneva, Switzerland This study was supported by a National Alcohol Research Center grant AA 05595-12 from the U.S. National Institute on Alcohol Abuse and Alcoholism, the World Health Organization (Geneva), the National Institute of Psychiatry (4275P) (Mexico), and the Consejo Nacional de Ciencia y Tecnología (CONACyT) (39607-H) http://www.who.int/substance_abuse/activities/injuries/en/ 1st Pan American Conference on Alcohol Policies, 28-30 November 2005, Brasilia, Brazil

INTRODUCTION (I) Alcohol consumption has been found to be a major risk factor for both intentional and unintentional injuries in the emergency department (ED) setting. Most studies have not tried to differentiate the risk of injury associated with the long-term (usual) alcohol consumption from the risk of short, acute and intermittent alcohol use. This difference may be crucial in targeting at risk population.

INTRODUCTION (II) The case-crossover design provides estimates of intermittent alcohol use over and above the base line risk associated with long-term alcohol consumption. The case-crossover seems also especially appropriate to study differences in risk across mode of injury (violence Vs non-violence).

INTRODUCTION (III) We used a case-crossover analysis to study the risk across mode of non-fatal injury, using a large WHO multicenter study of injured patients, collected in 2001-2002.

METHODS (I) Sample Adult patients, 18 years and older, admitted to the emergency department and reporting an injury was drawn from ED admission forms from the WHO Collaborative Study on Alcohol and Injuries, 2001-2002. We selected here those in Argentina, Brazil and Mexico. Canada was first included but since only 4 respondents were classified with a violence-related injury, it is not considered further.

METHODS (II) Mode of injury was categorized as unintentional injury (non-violence), intentional self-inflicted and intentional by someone else (violence related injury). Face-to-face interview-questionnaire of about 25 minutes in length were administered. The control information for each case of injury is provided by the patient himself based on his past exposure experience.

The case-crossover design provides estimates for the effect of intermittent alcohol use over and above the base line risk associated with long-term alcohol consumption. 1.http://www.pitt.edu/~super1/lecture/lec0821/001.htm 2.Maclure M, Mittleman MA. Should we use a case-crossover design? Annu Rev Public Health. 2000; 21:193-221.

METHODS (IV) Use of alcohol for each patient during the six hours period prior to the injury was compared with alcohol use during the same time period for the same day in the previous week for the pair matched strategy. Place of injury: “Where were you when you had your injury/accident?” Vs “Think about the time you had your accident (today) and remember the same time a week ago. Where were you a week ago?”

METHODS (V) Conditional logistic regression was used to calculate the matched-pair odds ratio (OR) and 95% confidence intervals (CI) (discordant pairs).

RESULTS (I) The total sample included 447 patients in Argentina (A), 489 in Brazil (B) and 455 in Mexico (M), for a total of 1391. Prevalence of violence was 13.5% (A=12.5%, B=10.2%, M=18.0%). About 46% of violence-related cases used alcohol (Vs 11.5 Non-Violence), 80% were males (Vs 63%), and 66% under 30 years (Vs 44%).

RESULTS (II)

RESULTS (III) 20.2 10.2 4.5 3.9

RESULTS (IV)

RESULTS (V)

DISCUSSION (I) In this sample of non-fatal injured patients attending 3 EDs across the region, we found that the risk of a violent related-injury increased with drinking [ (15.0- (5.8-39.1) ]. Patients with unintentional injury had a lower OR [ (4.2- (2.7-6.5) ].

DISCUSSION (II) If subjects decided to drink, increasing amounts may have pronounced consequences in their risk of triggering an injury, specially a violence-related injury. Changes from place of injury (street and drinking place) was also more associated with a violent related-injury than with an unintentional injury. Changing in places and alcohol use may nevertheless increase more the risk of an unintentional injury.

DISCUSSION (III) This study is limited to non-fatal cases of injury that comes to EDs facilities and although the study design provides a representative sample of patients from this facility, patients may not be representative of other ED facilities in the city or the country that participated.

DISCUSSION (IV) As is common with other emergency department studies, cases also cannot be assumed to be representative of those with injuries who do not seek medical attention. All analyses reported here are based on the patient’s self-reported alcohol consumption for differing time frames, and it is possible that patients were more likely to better recall their consumption immediately prior to an injury event than for any previous period. http://www.who.int/substance_abuse/activities/injuries/en/