Hazardous Drinking and Violent Mortality Among Males: Evidence from a Population- Based Case-Control Study

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1 Social Problems, 2016, 63, doi: /socpro/spw018 Article Hazardous Drinking and Violent Mortality Among Males: Evidence from a Population- Based Case-Control Study William Alex Pridemore University at Albany State University of New York ABSTRACT The goal of this study was to determine the risk of homicide victimization associated with an underlying pattern of hazardous drinking. Data were from the Izhevsk Family Study (IFS), a large-scale, population-based case-control study. There were two sets of cases: all men aged 25 to 54 years living in Izhevsk during October 2003 through October 2005 who were (1) homicide victims (n ¼ 45) or (2) homicide victims or died of injuries of undetermined intent (n ¼ 156). Controls were selected at random from a population register. The exposure, an ongoing pattern of hazardous alcohol consumption, was variously defined as drinking more than 20 liters of ethanol in the prior year, consumption of nonbeverage alcohols at least once per week, and a set of behavioral measures of problematic drinking. Extensive information was obtained via interviews with proxy informants living in the same household as cases and controls. Each measure of hazardous drinking was associated with increased risk of violent death, and nearly 60 percent of homicides were attributable to hazardous drinking. Results provide strong evidence of an association between an underlying pattern of hazardous drinking and vulnerability to violent death. KEYWORDS: alcohol; hazardous drinking; violence; homicide; victimization. This study investigated the association between an underlying pattern of hazardous drinking and risk of homicide victimization. The study makes several contributions to the literature. First, I studied ongoing alcohol misuse. While a high proportion of homicide victims are intoxicated at the time of the event (Kuhns et al. 2011), we know little about the impact on victimization of ongoing hazardous drinking. To explain homicide we must understand not only the immediate context of the incident but the background of victims and offenders, including lifestyle trajectories and ongoing disputes (Miles 2012). Second, I studied individuals. Although population-level studies are important when examining structural (Livingston 2008), cultural (Landberg 2008), and policy aspects (Pridemore, Chamlin, and Andreev 2013) of the alcohol-violence association, they do not contain information about whether individual victims or offenders were hazardous drinkers. Third, I studied homicide The original Izhevsk Family Study was funded by the Wellcome Trust. The author thanks Dave Leon and the IFS team for sharing these data. The author thanks Dave Leon and Colin Loftin for comments on and critiques of earlier drafts of this article. The author also thanks the Centre for Baltic and East European Studies and the Stockholm Centre on Health of Societies in Transition, both at Södertörn University in Stockholm, which provided support for his sabbatical, during which he carried out the analyses for and wrote the original article. Direct correspondence to: William Alex Pridemore, University at Albany State University of New York, School of Criminal Justice, 135 Western Avenue, Draper Hall 219, Albany, NY pridemore@albany.edu. VC The Author Published by Oxford University Press on behalf of the Society for the Study of Social Problems. All rights reserved. For permissions, please journals.permissions@oup.com 573

2 574 Pridemore victims. Substantial attention has been devoted to the association between alcohol and aggression (Felson et al. 2008; White et al. 2012) but less is known about the involvement of drinking in violent victimization (Felson and Burchfield 2004; Pridemore and Eckhardt 2008). Victims often play key roles in homicides and there is considerable victim-offender overlap (Miles 2012). Fourth, most prior similar studies failed to include data on controls, making it impossible to discern baseline levels of exposure and to compare drinking patterns of victims to non-victims. I addressed this limitation by employing data from a population-based case-control design. LITERATURE REVIEW Alcohol Consumption and Violent Victimization There are two general themes explaining the role of alcohol in vulnerability to violent victimization. The first is the impact of drinking and intoxication at the time of the event on victimization risk and injury severity. Not all characteristics associated with a homicide are contained in or proximate to the event (Miles 2012), however, and an underlying pattern of hazardous drinking can increase risk of homicide victimization regardless of drinking status at the time of the incident. These include (1) state dependence, when prior alcohol-related behavior or consequences (e.g., aggression toward others, financial disputes, antagonistic relationships, romantic quarrels) precipitate victimization, and (2) lifestyle exposure and opportunity, since traits like involvement in the nighttime economy (more common among heavy drinkers) can increase victimization risk. Thus, the second theme in this literature, and the focus of my study, is the risk of violent victimization due to an underlying pattern of hazardous drinking. Victims of violence often share risk factors with violent offenders, including excessive drinking (Wolfgang 1958). Lifestyle exposure theory (Hindelang, Gottfredson, and Garofalo 1978) posits some people are at greater risk of criminal victimization because they engage in behavior that exposes them to dangerous people, places, and situations. Hazardous alcohol consumption may be one such behavior. Intoxication may make someone an attractive target due to its role in (1) poor decisionmaking, which attracts derision from others; (2) physically isolating oneself, especially late at night; (3) impairing the physical ability to protect oneself; and (4) reducing the likelihood victims can identify their assailants, thereby decreasing the certainty element of deterrence (Shepherd, Sutherland, and Newcombe 2006). These explanations would suggest, relative to moderate or non-drinkers, heavy drinkers are at greater risk of violent victimization even when not drinking because their routine activities are more likely to have them spending time with motivated offenders and in riskier situations (Felson 1998; Lasley 1989). Hazardous Drinking A key element of the association between alcohol use and crime is drinking pattern. Recent research focused less on presence or absence of drinking, instead recognizing acute binge drinking or a pattern of hazardous drinking are more important risk factors for violence and other negative health outcomes. Hazardous drinking is usually described in terms of behaviors like heavy episodic, or binge, drinking (defined as five or more drinks in one sitting for males and four or more for females) and frequency of drunkenness. Jürgen Rehm and colleagues (2004) developed a hazardous drinking pattern score to rate how, on average, people in different cultures drink and how these patterns are related to the burden of disease. Hazardous drinking matters for premature mortality and other negative outcomes. In the larger Izhevsk Family Study (IFS) from which the data for my study were drawn, David Leon and colleagues (2007) found that relative to men who drank but did not have a drinking problem, men with a drinking problem were three times more likely to die prematurely. The authors attributed 43 percent of all premature mortality among these 25 to 54 year old men to hazardous drinking. In a study of nearly 18,000 college students, Cheryl Presley and Edgardo Pimentel (2006) found, even

3 A Case-Control Study of Hazardous Drinking and Violent Mortality 575 compared to heavy drinkers (a single episode of at least five drinks on one occasion within the last two weeks), the rate of negative consequences was three times higher for heavy and frequent drinkers (i.e., heavy drinkers who also drink at least three times per week). Hazardous drinking matters for violent offending. Kai Pernanen (1991) suggested dose-related effects were more important than the presence of alcohol. Kathryn Graham and Samantha Wells (2001) showed participants in incidents of severe aggression were more intoxicated than participants in incidents of less severe aggression and that intoxication was more important than drinking per se (Wells and Graham 2003). Others also found alcohol-related aggression more likely among those who binge drink or drink to intoxication (Giesbrecht and West 1997; Rossow 1996). Hazardous drinking matters during the period immediately preceding and at the time of the violent incident (Miles 2012). Jonathan Shepherd and Mark Brickley (1996) found even modest intoxication was not related to injury from violence but deep intoxication was, suggesting a threshold effect. Shepherd and colleagues (1988) found a dose-response effect such that the greater the intoxication level the greater the resulting injury due to violent victimization. Research by Wells and Graham (2003) showed drinking by itself was not related to respondent injury resulting from physical aggression but perceived level of intoxication was significantly associated with injury. An underlying pattern of hazardous drinking matters for assault victimization. Shepherd and colleagues (2006) found adolescents who used alcohol were more vulnerable than those who did not to be victims of aggression. Other research revealed problem alcohol use was a risk factor for subsequent violent victimization for boys and girls (Thompson et al. 2008), that victims older than 35 had a higher level of weekly consumption relative to the population (Shepherd et al. 1989), and that heavy drinkers experienced a higher rate of assault victimization than abstainers and moderate drinkers (Potter et al. 1999). Research also showed victims of violence drank more than non-victims on an average weekend, drank more in each weekend drinking session, and were more likely to drink more than ten units of alcohol in a drinking session (Shepherd and Brickley 1996). A study of Russian men found those who binge drank (defined in the study as 80 grams or more of ethanol in a drinking session) at least once per month were more than twice as likely as those who did not to be victims of violence (Stickley and Pridemore 2010). Cherpitel s (1994) review of emergency room studies concluded that no matter their drinking behavior in the hours preceding the event, relative to those presenting to the emergency room for other injuries people with violence-related injuries were more likely to be problem drinkers. Studies of hazardous drinking and homicide victimization are rare, and absent from the sociological and criminological literature, but there is evidence of an association. Using the National Mortality Followback Survey, Guohua Li, Gordon Smith, and Susan Baker (1994) found that relative to those who died from other causes, homicide victims were more likely to be heavy drinkers. In a casecontrol study Frederick Rivara and associates (1997) examined risk of homicide victimization in the home associated with alcohol use. They interviewed proxies close to decedent cases and living controls to obtain information about drinking patterns. Relative to abstainers, hazardous drinkers were 10 to 18 times more likely to become a victim of homicide in the home. The Importance of a Case-Control Design to the Study of the Association between Hazardous Drinking and Homicide Victimization Without comparable data from controls it is impossible to determine the magnitude of victimization risk of hazardous drinkers relative to non-hazardous drinkers. Case-control designs are well suited to this situation but are rare in criminology (Loftin and McDowall 1988). Prospective cohort designs provide a rigorous alternative but are inefficient and expensive when studying an extremely rare event like homicide where a tiny proportion of those at risk become victims. Further, hazardous drinkers are likely to be excluded when recruiting a cohort. Case-control designs yield information comparable to cohort designs with a substantial discount in cost and time (Rothman 1986), achieving the same power with a much smaller sample.

4 576 Pridemore Case-control designs sample on the basis of the outcome, in this case homicide victimization. Victims are the cases, which are classified based on exposure to the risk factor, in this case hazardous drinking. Instead of obtaining denominators for rates, a control group is sampled from the source population that yielded cases. Controls are also classified based on exposure to hazardous drinking. The control group provides the relative size of the exposed and unexposed components of the source population so they must be sampled independently of exposure status (Rothman 1986). In short, controls are representative of those that could have become cases (in the present study, they had a chance of becoming homicide victims) but did not. When cases are drawn from a precisely identified population and when the controls are sampled from this same population the study is said to be population based. The most common way to compare cases to controls is to calculate an odds ratio. For rare outcomes like homicide victimization the odds ratio approximates relative risk, making results easier to interpret. While case-control studies provide a rigorous design, present logical and easy to understand results, are more efficient than cohort studies, and are well suited to many crime-related topics, they still require considerable effort and expense and thus are rare in studies of violence. I took advantage of data from a broader case-control study of all-cause premature mortality among males. Since cause of death information was available from these data, together with detailed information on alcohol consumption, I was able to determine individual-level risk of homicide victimization associated with hazardous drinking, which would be impossible to estimate using aggregate data or without information on controls. DATA AND METHOD Population and Study Design Data came from the Izhevsk Family Study (IFS), a large-scale population-based case-control study of premature mortality among working-age Russian men (Leon et al. 2007; Tomkins et al. 2007). 1 The study had ethical approval from Izhevsk Medical Academy and London School of Hygiene and Tropical Medicine. Izhevsk is a typical Russian industrial city in the western Urals, with a population of about 630,000 residents in the year prior to beginning IFS data collection. At the time of the study Izhevsk had a typical demographic profile for a medium-sized Russian city and its residents had a life expectancy and a distribution of deaths by cause in working-age men similar to Russia as a whole, which were key reasons for its selection as a representative study site. The Udmurt Republic (in which Izhevsk is located) had a homicide rate (20.4 per 100,000) at the time similar to the all- Russian homicide rate (21.5 per 100,000). Original IFS cases were deceased men aged 25 to 54 who died from any cause between October 20, 2003 and October 3, 2005, and who were living in an Izhevsk household with at least one other person at time of death. 2 Cause of death was coded by certifying doctor or pathologist using the International Classification of Diseases, 10 th revision. 3 Controls were living men selected from a 2002 Izhevsk population register who were living in a household with at least one other person. Each month new controls were randomly selected from within five-year age bands of the sampling frame, such that the control sample with proxy interviews was the same age as the accumulating series of cases with proxy interviews. A team of 34 interviewers used a structured questionnaire to obtain information from proxy respondents living in the same household as cases or controls. Most case proxy interviews took place 1 Documentation about the IFS can be found at the IFS website ( retrieved July 26, 2016). 2 In the United States, homicide offending and victimization rates are highest among men younger than 25 years old and then steadily decline with age. In Russia, however, homicide victimization rates are highest among (and very similar between) those aged 25 to 34, 35 to 44, and 45 to 54, and rates among these age groups are about double those aged 15 to 24 (Pridemore 2003a). Thus, my sample includes the specific group that typifies Russian homicide victimization. 3 For more information about the ICD, see (retrieved July 26, 2016).

5 A Case-Control Study of Hazardous Drinking and Violent Mortality 577 six to eight weeks after death. Case and control proxy interviews were carried out at the same rate. Interviewers returned to an address up to three times to get a response. When more than one proxy was available a pre-specified priority was used, with wives or partners as first choice. Most proxy interviews were with wives or partners (59 percent for cases, 85 percent for controls), followed by mothers (21 percent for cases, 9 percent for controls). Less common proxies were adult offspring, siblings, fathers, or other relatives. Interviews with proxies took place in private to avoid contamination. Questions were derived from established and validated instruments, and in most cases the reference period for behaviors and experiences was the prior 12 months. Measures Dependent variables were homicide (ICD-10 codes: X85-X99, Y00-Y09, Y87.1) and a category combining homicide and external injury deaths due to events of undetermined intent (EUIs) (Y10-Y34, Y87.2, Y89.9). The EUI category is used only when there is documentation in the death record that the intent of the injury cannot be determined. I included these because (1) there was a low number of homicides; (2) some proportion of these EUI deaths were homicides, as it includes only deaths from homicide, suicide, or accidental injury; and (3) this category is used disproportionately in Russia, especially following the collapse of the Soviet Union (Andreev et al. 2015; Gavrilova et al. 2008). 4 The rate of male EUI deaths was 46 per 100,000 men in Russia in 2009, compared to about 2 to 3 per 100,000 men in the United States and the European Union-15. I used four measures of alcohol consumption, three of which I defined as hazardous drinking. The first was a continuous measure of volume in liters of ethanol consumed in the past year obtained by the standard quantity-frequency approach (Dawson and Room 2000). Subjects were asked about the frequency of consumption of all beverage types (every day or more often, nearly every day, three to four times per week, one to two times per week, one to three times per month, a few times per year, almost never, or never). The amount of each beverage type consumed on a usual occasion was obtained for categories defined in units commonly used by Russians (i.e., bottles of beer, grams of wine and spirits). 5 Ethanol concentrations for beverage types were measured after inspection of what was available in Izhevsk and laboratory analysis of locally purchased vodkas (McKee et al. 2005). Beer was taken as 4.5 percent ethanol by volume, wine 12 percent, and spirits 43 percent. My second measure categorized the volume in liters of ethanol into abstainer,.1-5.0, , , , or greater than 20. For this measure I defined hazardous drinking as consumption of more than 20 liters of ethanol in the prior year. The third measure was frequency of consumption of non-beverage alcohols. These are ethanolbased liquids not intended for drinking (e.g., colognes, medicines, cleaning fluids). They are not classified as alcoholic drinks so avoid excise duty, making them up to six times cheaper per unit of ethanol than vodka (Gil et al. 2009). Toxicological analyses of non-beverage alcohols in Izhevsk showed many contained very high ethanol concentrations (60 to 97 percent) (McKee et al. 2005). For this variable I defined hazardous drinking as consumption of non-beverage alcohols at least once per week. The final indicator of hazardous drinking, which I called problem drinking, was based on behavioral measures. There are calls to use behavioral indicators to gauge problem drinking (Room 2005) and the single case-control study of alcohol and homicide victimization (Rivara et al. 1997) employed such measures. At the IFS design stage a systematic review (Tomkins 2006) concluded validity of 4 This category can be considered a gauge of vital statistics data quality: the greater its use the poorer the data quality for homicide, suicide, and accidental injury deaths. Whether the death is purposely misclassified (i.e., a known homicide or suicide is categorized as undetermined intent), which some believe to be the case for a large number of such deaths in Russia, or whether the intent is truly unknown, the result is a large number of true homicides end up in this event of undetermined intent category (Andreev et al. 2015; Gavrilova et al. 2008; Pridemore 2003b). 5 Volume was missing for some respondents because answers to six questions (volume and frequency of beer, wine, and spirits) were required to estimate this amount. This measure did not include consumption of non-beverage ethanol.

6 578 Pridemore proxy informant data on alcohol consumption is improved if restricted to questions on directly observable behaviors. Problem drinking was dichotomous and coded one if during the previous 12 months the person had gone on a drinking binge or had at least twice per week occurrence of hangovers, drunkenness, or falling asleep with clothes on due to drinking. The former is called zapoi in Russian and defined as continuous drunkenness of at least two days during which the person is completely removed from normal social life. I included controls for the known determinants of premature mortality among Russian males aged 25 to 54 (Leon et al. 2007; Pridemore et al. 2010) and for age. Smoking status was categorized as non-smokers, ex-smokers, or current smokers. 6 Marital status was measured as living together in a registered marriage, living together in an unregistered marriage, never married, divorced or separated, or widowed. Education was measured as complete higher education, incomplete higher, specialized secondary, complete secondary, professional, or incomplete secondary (see Pridemore et al for more information on the Russian specialized and professional categories). The age groups were 25-29, 30-34, 35-39, 40-44, 45-49, 50-54, and 55 and older. Analysis I used logistic regression to estimate mortality odds ratios (ORs) comparing cases to controls. 7 I estimated separate models for both of the dependent variables and for each of the four measures of alcohol consumption (including the three measures of hazardous drinking). All odds ratios were mutually adjusted for the categorical control variables described above. RESULTS Table 1 shows the distribution of alcohol consumption. Mean consumption during the prior year was 17 liters for homicide victims and 10 liters for controls. Categorical volume of consumption shows 29 percent of homicide victims consumed more than 20 liters of pure ethanol in the prior year compared to 14 percent of the controls. Forty percent of homicide victims drank non-beverage alcohol at least once per week compared to only 5 percent of controls. Sixty-four percent of homicide victims were problem drinkers, as defined in this study, compared to 20 percent of controls. Table 2 shows results for homicide cases. Model 1 shows a non-significant association (b ¼.009, p ¼.23) between risk of homicide victimization and volume of ethanol as a continuous measure. Model 2 shows odds ratios for this association when volume is a categorical variable using moderate drinkers as the reference group. All ORs were non-significant. Model 3 shows that relative to men who never or almost never drank non-beverage alcohol, those who drank non-beverage alcohol one to two times or three or more times per week were nine and seven times, respectively, more likely to become a homicide victim. Model 4 shows that relative to non-problem drinkers, problem drinkers were nearly five times more likely to become a homicide victim. 6 I included smoking as a control for two reasons. First, smoking is a known determinant of premature mortality among this sample. Second, since the main association is between an underlying pattern of hazardous drinking and homicide victimization risk it is important to control for other risk-taking behavior because of the clustering of health-endangering behaviors as manifestations of underlying dispositions and personality traits. Some theories also account for the co-occurrence of problematic behaviors and adverse health conditions in terms of the generality of distal traits like low self-control and impulsivity. Smoking is a typical indicator of such an underlying trait and including it in the model is an attempt to control for these risky traits and to isolate the effect on homicide risk of an underlying pattern of hazardous drinking. 7 There were 45 homicides and 156 total violent deaths. Given 1,750 controls this means there were about 39 and 11 controls per case, respectively. The number of controls was due to the number of cases in the original IFS. Incremental benefits to statistical power diminish rapidly beyond three to four controls per case (Breslow 1982). Still, Hennessy and colleagues (1999) showed more than five controls per case may be warranted where phi >.2 (phi is the correlation coefficient for exposure between cases and controls) or P 0 <.15 (P 0 is the prevalence of exposure among controls). In this sample phi ¼.19 for exposure to the problem drinking variable, and P 0 ¼.05 for controls on the exposure of consuming non-beverage alcohol at least once per week. Because information on all controls was available without further cost in time, money, or effort, and since there was no harm and possibly some benefit in including more than four to five controls per case, I included all controls.

7 A Case-Control Study of Hazardous Drinking and Violent Mortality 579 Table 1. Distribution of Drinking Variables by Homicides, Homicides Plus Injury Deaths of Undetermined Intent (EUIs), all Original IFS Cases, and Controls Homicides Homicides Plus EUIs All Original IFS cases Controls Liters of ethanol in last year Abstainer > Mean Standard deviation n ,473 1,538 Frequency of consumption of non-beverage alcohol A few times per year or less times per month times/week or more times per week n ,725 1,705 Problem drinker No Yes n ,596 1,532 N ,750 1,750 Table 3 provides results for the combined category (homicides plus EUIs). Model 1 shows a positive and significant association between liters of ethanol consumed and risk of violent death (b ¼.019, p <.001). Model 2, however, suggests the linear association in Model 1 is not a true representation of the relationship. Relative to even moderate drinkers, heavier drinkers were not at greater risk of a violent death until the 20 or more liters category, revealing a threshold effect. Model 3 shows that compared to men who never or almost never drank surrogates, men who drank non-beverage alcohol one to two times or three or more times per week were 11 and 15 times more likely, respectively, to die a violent death. Model 4 shows that compared to men who were not problem drinkers, problem drinkers were five times more likely to die a violent death. Supplemental Analyses To determine if the impact of hazardous drinking on homicide victimization remained after controlling for volume of consumption I adjusted the non-beverage alcohol consumption and problem drinking ORs for volume as a continuous variable. Homicide results showed that consumption of non-beverage alcohol and problem drinking remained significant and the volume measure was nonsignificant. Inferences drawn from the homicides plus EUIs models also remained the same as above, with similarly high ORs (in the range of 14) for non-beverage alcohol consumption and only slight attenuation of the odds ratio for the problem-drinking indicator (OR ¼ 4.2, CI: ). In each case, the volume measure was non-significant. Hazardous drinkers likely cluster on a set of non-drinking characteristics that represent risky lifestyles and that put them at generally higher risk of homicide victimization. To account for this I

8 580 Pridemore Table 2. Association of Homicide Mortality with Indicators of Alcohol Consumption Model 1 Model 2 Model 3 Model 4 Liters Continuous Liters Categorical Non-beverage Alcohol Problem Drinker B SE P-value Odds Ratio Odds Ratio Odds Ratio (95% CI) (95% CI) (95% CI) Liters of ethanol in last year Liters categorical Abstainer 2.2 (.6-7.8) (reference) (.3-4.2) (.7-8.7) ( ) > (.8-7.4) Frequency of consumption of non-beverage alcohol A few times per year or less 1.0 (reference) 1-3 times per month 1.2 (.1-9.4) 1-2 times/week 8.7 ( ) 3 or more times per week 7.1 ( ) Problem drinker No 1.0 (reference) Yes 4.7 ( ) Note: All estimates are adjusted for age group, smoking status, marital status, and education. added controls for lifetime prevalence of incarceration and prior year prevalence of violent victimization. I reestimated the models for frequency of non-beverage alcohol consumption and for problem drinking adjusting for these two variables. Again, the inferences drawn remained the same and the ORs remained similar to those presented in Tables 2 and 3. Finally, I used Sander Greenland s (1987) method to estimate the attributable fraction, which is the proportion of the event rate in the exposed population that would be reduced if the exposure were not present. To do this I first collapsed the hazardous drinking indicators so that hazardous drinking was defined either as drinking surrogates at least once per week or being a problem drinker. The attributable fraction for all violent deaths was 57 percent and for homicides was 58 percent.

9 A Case-Control Study of Hazardous Drinking and Violent Mortality 581 Table 3. Association of All Violent Deaths (Homicides plus EUIs) with Indicators of Alcohol Consumption Model 1 Model 2 Model 3 Model 4 Liters - Continuous Liters Categorical Non-beverage Alcohol Problem Drinker b SE P-value Odds Ratio Odds Ratio Odds Ratio (95% CI) (95% CI) (95% CI) Liters of ethanol in last year <.001 Liters categorical Abstainer.6 (.3-1.4) (reference) (.3-1.4) (.7-3.0) (.9-4.4) > ( ) Frequency of consumption of non-beverage alcohol A few times per year or less 1.0 (reference) 1-3 times per month 1.5 (.5-4.7) 1-2 times/week 11.0 ( ) 3 or more times per week 14.7 ( ) Problem drinker No 1.0 (reference) Yes 5.0 ( ) Note: All estimates are adjusted for age group, smoking status, marital status, and education. DISCUSSION The association between alcohol and aggression has received considerable attention, though less is known about the effect of drinking on criminal victimization (Felson and Burchfield 2004). The research that does exist has nearly always examined non-lethal victimization, but homicides often differ from assaults in key respects so studying homicide victims separately is important. The literature also suggests that whether aggression or victimization is of interest, hazardous drinking may play a more important role than simply drinking per se. This study addressed these limitations and also contributes to the literature by (1) examining the effects of an underlying pattern of hazardous drinking instead of solely intoxication at the time of the event, (2) focusing on individuals, (3) recognizing the

10 582 Pridemore importance of victim characteristics when explaining homicide, and (4) using a case-control design to include a control group, which is often lacking in epidemiological studies of drinking and homicide. Results show that men aged 25 to 54 with a pattern of hazardous drinking in the prior year whether measured as very high volume of ethanol intake, consumption of non-beverage alcohol, or behavioral indicators like frequent drunkenness or hangovers were at substantially higher risk of violent death compared to men who did not drink hazardously. This risk remained after adjusting for the known determinants of death among the group and after controlling for indicators of risky lifestyles like smoking, lifetime prevalence of incarceration, and prior year prevalence of violent victimization. Problem drinkers were five times more likely than non-problem drinkers to die a violent death, and nearly 60 percent of all homicides were attributable to hazardous drinking. These results are consistent with prior studies of drinking and victimization, were obtained using a rigorous casecontrol design, and extend the association between an underlying pattern of hazardous drinking and violent victimization to homicide. The latter has only been shown once in the prior literature (Rivara et al. 1997), and that study was limited to homicides that took place in the home. Methodological Strengths of the Study A key methodological strength of this study is that the instrument contained many and specific questions about drinking. Quantity-frequency measures (Dawson and Room 2000) were used to gauge total volume of ethanol consumed. Ethanol concentration for vodka (i.e., the beverage preference of this population) was not assumed, but calculated based on an inspection of what was available for purchase in Izhevsk and on laboratory analysis using gas chromatography and mass spectrometry (McKee et al. 2005). To measure a specific type of hazardous drinking we asked about frequency of consumption of non-beverage alcohol. We also used behavioral measures of problem drinking (Room 2005) asking how often the subjects went on an extended drinking binge, had hangovers, and fell asleep with their clothes on because they were drunk which have been shown to be of superior validity when obtaining information from proxies because they are directly observable (Tomkins 2006). Another methodological strength was the case-control design. Most studies of the alcoholvictimization link did not include a control group. This is understandable given costs required of a case-control study, but rigorous designs are required to advance knowledge in this area. While casecontrol designs are not as high as randomized controlled studies on the evidence hierarchy, I described earlier the advantages of case-control over cohort designs for certain topics. In short, without comparable data from a control group we are unable to determine the risk of violent victimization of those with a given exposure relative to those without it. A final key strength of this study is that it was population based. We started with all deaths of men aged 25 to 54 that were a resident of the city. Controls were randomly selected from a population register of that city. While the research team was unable to obtain proxy interviews for all cases and controls, the association of all-cause premature mortality with registration at the city s narcology clinic for all men was the same (17 percent) for men for whom a proxy interview was obtained and men for whom a proxy interview was not obtained (Leon et al. 2007:2003; Table 2). This means selection bias is unlikely to explain the findings about alcohol surrogates and hazardous drinking because both are related to the probability of narcology clinic registration. The Role of Alcohol Consumption Pattern in Violent Victimization: Hazardous Drinking The findings from this study support the assertion that drinking per se is less important than hazardous drinking for the risk of violent victimization. First, while initial estimates showed an association between volume consumed (as a continuous variable) and risk of violent death (see Model 1 in Table 3), this does not tell the entire story. For example, Table 1 shows that there are only minor differences in the total proportion of homicide victims (and of the homicides plus EUIs category) and controls that drank between 5 and 20 liters of ethanol in the prior year. The differences begin in the

11 A Case-Control Study of Hazardous Drinking and Violent Mortality to 20 liters category, and it is only in the 20 or more liters category where the difference between the two case categories and the controls is large. Thus, the findings for the continuous volume variable are likely masking a nonlinear threshold effect. This is confirmed in Model 2 in Table 3. When the effect of volume is estimated as a categorical variable, relative to moderate drinkers the risk of violent death is significant only for the 20 or more liters category. Such a high volume is itself characteristic of hazardous drinking, as 20 liters of pure ethanol in the last year is the equivalent of about 67 bottles (750 ml) of vodka or 1,000 pints of beer. Further, when a continuous measure of volume was included together in a model with the frequency of consumption of non-beverage alcohol, and then together in a model with problem drinking, the mortality odds ratios for the latter two were barely attenuated while the volume variable was not significant (results not shown in tables). Just how much hazardous drinking influences the risk of violent victimization is shown in the models containing frequency of consumption of alcohol surrogates and problem drinking. In Table 3, even drinking non-beverage alcohol one to three times per month did not increase victimization risk. However, relative to men who never or almost never drank alcohol surrogates, those who drank them one to two times or three or more times per week were about 11 and 15 times more likely, respectively, to die a violent death. The behavioral measures defining the problem drinker category may be the most intuitive for many people. Relative to men who were not problem drinkers, problem drinkers were about five times more likely to become a homicide victim. 8 Why are Hazardous Drinkers at Higher Risk of Violent Victimization? Why are male hazardous drinkers at such a greater risk for homicide victimization? One explanation is that prior alcohol-related behavior or consequences help precipitate victimization. As Caroline Miles (2012) argues, when trying to understand even intoxication-related homicides one must recognize the importance of background context and the ongoing precursors to a homicide event. This is not dissimilar to a state dependence perspective of repeat victimization (Lauritsen and Quinet 1995), where eventual homicide victimization might be caused by earlier behaviors (e.g., hazardous drinking) or their consequences, especially since hazardous drinkers are routinely involved in violence (Miles 2012). The accumulation of negative outcomes aggression toward or conflict with others, strained and antagonistic relationships, economic insecurity, financial disputes, romantic quarrels, troubles at work can increase anger and frustration in the heavy drinker and in others like family members, friends, and acquaintances with whom the heavy drinker spends most of his time. Of course, we know a large proportion of homicides occur between people who know each other. While hazardous drinking s associations with many negative outcomes are almost certainly bidirectional over time, a practical outcome is the increased risk of violence associated with these outcomes. Another explanation may come from lifestyle exposure and opportunity theories. Involvement in nighttime activities and the nighttime economy revolves largely around alcohol consumption and/or bars, and such involvement is associated with a higher risk of victimization for adults (Moore and Foreman-Peck 2009) and adolescents (Felson et al. 2013). Miles (2012) found that homicide victims histories often included chaotic lifestyles, alcohol misuse, and a declining pattern of behaviour (p. 885). This type of lifestyle likely contributes to higher risk of violent victimization given greater exposure to motivated offenders and dangerous places or situations. Further, alcohol use disorders are related to antisocial personality disorder (Grant et al. 2004), which is associated with a greater likelihood of violent offending and victimization, and Miles (2012) found that homicide victims underlying alcohol abuse was similar to that of homicide offenders. 8 These ORs are large compared to those normally encountered in epidemiology and compared to those in studies of problem drinking and non-lethal violent victimization. This is probably due to quantifying the effect of hazardous drinking instead of simply using an indicator of volume. Evidence for this is found in the fact that these ORs are comparable to those in the only other case-control study of alcohol consumption and homicide victimization (Rivara et al. 1997).

12 584 Pridemore A third explanation may be that those with an underlying pattern of hazardous drinking are more likely to be intoxicated at the time of the incident. Toxicology (Kuhns et al. 2011) and mixed methods (Miles 2012) studies show a high proportion of homicide victims were drinking at the time of the event, and there are several potential reasons why heavy drinking in the period prior to the event may increase the risk of violent victimization and injury severity. Alcohol impairs information processing, increases miscommunication, lowers inhibition, leads to poor decision making, and disrupts motor skills. Lab studies show it makes one more aggressive. All of these can make the intoxicated person an irritant to others, increase the likelihood of conflict, and escalate the severity of conflict (McClelland and Teplin 2001; Pernanen 1991; Shepherd et al. 2006). Impaired judgment and poor decisions may also result in putting oneself in risky situations, including physical isolation. Decreased physical and mental capacity makes it difficult to retaliate or protect oneself in the event of an attack. This makes for an attractive target to assailants looking for a victim, with the added benefit to the offender that the drunk victim will likely be unable to identify him to police (Shepherd and Brickley 1996). Using data from the National Violence Against Women Survey, Richard Felson and Keri Burchfield (2004) examined the association between drinking and violent victimization. An important contribution of their study was that the authors distinguished between risk of victimization while sober and risk while drinking. They found frequent and heavy drinkers were no more likely than those who were not frequent and heavy drinkers to be victimized while sober, but they were at a greater risk of violent victimization while drinking. The strength of this association was especially strong for men. Felson and Burchfield s research suggests situational characteristics resulting from the eventual victim s drinking at the time of the incident may be a better explanation than the lifestyle exposure explanation. They argue drinking victims motivate or disinhibit the offender, and point to the results of Gary Michael McClelland and Linda Teplin s (2001) analysis of police-citizen encounters that suggest that men are likely to be verbally aggressive when drinking, thereby provoking others to use violence. Future Research There are several elements of the association between hazardous drinking and violent victimization that deserve attention but that are unexamined here. First, although I have speculated about the potential reasons why a pattern of hazardous drinking would be associated with violent victimization, the precise causal pathways deserve further attention. Second, and similarly, it is important to determine if this association remains after controlling for drinking status at the time of the violent event. Several of the studies cited above suggest it does, but further scrutiny is necessary, especially for homicide victimization. Non-lethal violent victimization can be not only a consequence of problem drinking but a cause of it. John Rich and Courtney Grey s (2005) qualitative study of young black men led them to hypothesize that serious violent victimization might be a risk factor for self-medication. A longitudinal study of an urban African American cohort confirmed this hypothesis, showing violent victimization in young adulthood increased alcohol use later in life (Eggleston-Doherty et al. 2012). Other studies provide evidence that violent victimization is a common pathway to self-medication among women. Thus, further research is required to better understand the impact of victimization on alcohol use and the nature of the reciprocal relationship between them. A final major area not covered in the present study is the impact of hazardous consumption on homicide victimization among women. Due to the goals of the larger IFS study, my sample consisted solely of men. Future research on the relationship between hazardous drinking and homicide victimization among women is important, especially because (1) the literature reveals a bidirectional association between alcohol consumption and violence among women (Thompson et al. 2008), (2) of the risk of self-medication following violent victimization, and (3) of the association between alcohol consumption and intimate partner violence (Thompson, Saltzman, and Bibel 1999) and sexual victimization (Norris 2008).

13 A Case-Control Study of Hazardous Drinking and Violent Mortality 585 Limitations This study was carried out in Russia, where levels of alcohol consumption, hazardous drinking, and homicide are high, and thus the findings here may not generalize to other nations. Second, while non-beverage alcohols are consumed in every nation, the use of these alcohol surrogates is higher in Russia than in most nations. Future studies may need to use alternative localized behavioral measures of hazardous drinking. Nevertheless, the results presented here were consistent across multiple indicators of hazardous drinking and consistent with findings about hazardous drinking and violent victimization in other nations like the United States, the United Kingdom, and Canada (Rivara et al. 1997; Shepherd and Brickley 1996; Wells and Graham 2003). Third, the original IFS collected data on males only due to the nature of the Russian mortality crisis, and thus we do not have information on females. Although homicide offending and victimization rates are several times higher for males than females and thus the focus on males is warranted, the impact of hazardous drinking on female homicide victimization may be different for women relative to men and thus future research should examine the association among women. Fourth, intoxication at the time of the event cannot be determined from the data, and thus it may be that some portion of the effect of an underlying pattern of hazardous drinking on risk of homicide victimization may be due to the effects of drinking immediately prior to the event. Of course, those with an underlying pattern of hazardous drinking will be intoxicated more often than others and so the latter overlaps with the former and as discussed above there are multiple theoretical reasons to believe an underlying pattern of hazardous drinking increases risk of homicide victimization regardless of drinking status at the time of the incident. Fifth, homicide is a rare event and thus there were a relatively small number of known homicides in this analysis. It is not difficult to obtain general information about a larger number of homicide victims (e.g., sex, age) and incidents (e.g., weapon, location, victim-offender relationship) from vital statistics or police data. These routine data, however, do not contain detailed information about the victim such as alcohol use over the prior year (or information on other risk factors) nor do they contain information on controls. Unfortunately this is a necessary trade-off if one wishes to undertake detailed analysis of the characteristics of homicide victims and, while necessary, it is still a limitation. Luckily, the case-control approach is well suited to this type of study and similarly small numbers of cases are not uncommon in case-control studies of medical and epidemiological studies of rare outcomes. Another limitation stems from the small number of cases with known homicides. In an attempt to increase the number of violent deaths, I also carried out sensitivity analyses using deaths from external events of undetermined intent (Y10-Y34, Y87.2, Y89.9). This category is disproportionately used in Russia, especially in the post-soviet era. 9 Deaths in the EUI category are by definition homicides, suicides, or accidental injuries, but since this classification contains an unknown proportion of nonhomicides this raises questions about the validity of its inclusion. While an empirical question, the non-homicide EUI deaths may be more strongly associated with alcohol than the homicide EUI deaths, which would bias upward the estimates of the association between hazardous drinking and homicide. The inferences drawn about the association with hazardous drinking are essentially the same for homicide and for these EUI deaths, however, and the mortality odds ratios for the problem drinking variable are the same for each (homicide: OR ¼ 4.7, CI: ; EUI: OR ¼ 4.9, CI: ). Further, the inferences drawn about the association between hazardous drinking and suicide mortality in this sample are the same as for homicide, and the mortality odds ratio for problem 9 Andreev and colleagues (2015) used data on nearly three million deaths from external causes in Russia to create a method for reclassifying EUIs as homicides, suicides, or non-transport accidents. They found (1) 36 percent of EUI deaths were recategorized as homicides, 16 percent as suicides, and 48 percent as non-transport accidents, and (2) 33 percent of homicides, 13 percent of suicides, and 14 percent of non-transport accidents were categorized as EUIs. They showed the 2011 Russian homicide rate would have been 82 percent higher than officially reported by vital statistics data had EUIs been correctly coded.