Increased alcohol consumption following stress has been demonstrated in animal models (
Fahlke et al., 2000;
Chester et al., 2004) and drinking alcohol is one way that humans cope with feelings of anxiety, anger and sadness when faced with traumatic experiences (
Volpicelli et al., 1999). The original tension-reduction hypothesis posits that alcohol reduces fear associated with conflict (Conger, 1956), but the relationship between tension and alcohol consumption is complex, involving gender differences, alcohol expectancies and motivations, perceived stress and adaptive coping mechanisms (Carney et al., 2000;
Cooper et al., 1992b). Experimental laboratory studies on stress and human alcohol consumption suggest that exposure to stressful events can alter subjective effects of alcohol, but may not increase alcohol consumption (
de Wit et al., 2003;
Söderpalm and de Wit, 2002). Daily diary studies have been used to investigate the impact of stress and mood on drinking (Armeli, Carney, O'Neil, Tennen and Affleck 2000; Young & Orei, 2000; Armeli, Tennen, Affleck & Kranzler, 2000; Schroder and Perrine 2007;
Park et al., 2004), but the results have not been consistent, even when examining within-person effects. A possible reason for inconsistencies in alcohol consumption within and between individuals exposed to daily hassles and stressors is that the source and type of stress matters (
Shrout et al., 1989). For example, politically motivated mass violence such as terrorism is more likely to cause psychological impairment than natural or technological disasters (Norris 2002;
Dohrenwend 2000). Terrorism, a fateful trauma, (i.e., trauma that occurs independently of an individual's personal traits;
Dohrenwend 2000), provides a natural experiment in which factors affecting subsequent alcohol consumption can be investigated.
The terrorist attack on the New York City World Trade Center (WTC) on September 11, 2001, constitutes such an event, as it was highly stressful for individuals in lower Manhattan (
Galea et al., 2002; Schlenger et al., 2002) and nearby areas (
Hasin et al., 2007). Increased alcohol consumption after the 9/11 attack was demonstrated in Manhattan adults (
Vlahov et al., 2002,
2004a,
2004b), New York City high school students (
Wu et al., 2006) and in adult drinkers from a New Jersey county near lower Manhattan, the site of the 09/11/01 terrorist attack (
Hasin et al., 2007). Further, increases in drinking were still present two years after the WTC attack (Boscarino, Adams and Galea, 2006). We previously showed that alcohol consumption after 09/11/01 was significantly higher in those who were within five miles of the WTC on 09/11/01 compared to those further away, while knowing someone who was killed in the attack was not (
Hasin et al., 2007). Importantly, the significant association between proximity to the WTC and alcohol consumption was not moderated or mediated by previous alcohol dependence (
Hasin et al., 2007). While the consistency of 09/11 effects on drinking has recently been summarized in a meta-analysis (
DiMaggio et al., 2009), little is known about individual characteristics influencing drinking after exposure to such fateful trauma.
One set of characteristics that merit investigation are drinking motives. A growing body of research suggests that drinking motivated by a desire or need to regulate positive versus negative affect is associated with unique patterns of alcohol use and distinct etiologic processes (
Kuntsche et al., 2005,
2006;
Cooper et al., 2008;
Cox and Klinger, 1988,
1990;
Cooper 1994;
Cooper et al., 1995). Drinking motives are persistent over time, predict later problem drinking (
Bennett et al., 1999;
Jackson and Sher, 2005) and are partly heritable (
Prescott et al., 2004;
Agrawal et al., 2008). Those who drink to cope with negative affect, including stress-related drinking, are at greater risk of alcohol problems than others (
Cooper et al., 1992b;
Cooper 1994, 1995;
Read et al., 2003). Drinking to enhance positive affect has been conceptualized as an appetitive motivational process (
Cooper et al., 2008,
1995) that prospectively predicts heavy drinking and drinking to intoxication (
Read et al., 2003;
Schulenberg et al., 1996). In our prospective study of adult drinkers, drinking to reduce negative affect at baseline (1991-1992) increased the risk for first-time occurrence of DSM-IV alcohol dependence one year (
Carpenter and Hasin, 1998a) and ten years later (
Beseler et al., 2008).
The impact of drinking motives on alcohol consumption after exposure to a fateful traumatic event has never been investigated. Our prospective study provided a unique opportunity to investigate the effects of drinking motives measured at baseline (1991-1992) and later proximity to a fateful trauma, the 9/11 attack, on subsequent alcohol consumption. We addressed two questions: (1) Did drinking motives measured ten years prior to 09/11/01 predict alcohol consumption after 09/11/01 above that predicted by proximity to the WTC? (2) Did proximity to the WTC moderate or mediate the effect of drinking motives on post-09/11/01 drinking? We hypothesized that drinking to reduce negative affect would predict increased drinking after 09/11/01 and that this motive could interact with proximity to the WTC, resulting in higher levels of alcohol consumption among those in close proximity to the attack.