Leaving Las Vegas: Exposure to Las Vegas and risk of suicide.

Residents of Las Vegas, Nevada have much higher suicide rates than residents of other metropolitan counties in the USA. Whether the risk of suicide among visitors to Las Vegas is also significantly elevated has been difficult to assess because person-time denominator information is not available. We used a case-control design to examine the association between exposure to Las Vegas and risk of suicide expressed as mortality odds ratios. We conceptualized four different types of potential suicide risk with respect to Las Vegas: (1) risk of suicide among usual residents of Las Vegas ("chronic risk"), (2) risk of suicide among temporary visitors to Las Vegas ("acute risk"), (3) risk of suicide among Las Vegas residents visiting elsewhere ("leaving Las Vegas risk"), and (4) risk of suicide among travelers in general ("traveler risk"). Controlling for age, gender, marital status, and year effects, the odds of suicide among Las Vegas residents was at least 50% greater than among residents elsewhere in each of the three decades we observed. Visitors to Las Vegas were at double the risk compared to those who stayed in their home county. Leaving Las Vegas was associated with a greater than 20% reduction in risk for suicide. Traveling to Las Vegas is associated with a twofold increase in risk compared to traveling elsewhere. We discuss three possible theoretical frameworks to help explain our observed results: ecological effects, whereby social factors unique to Las Vegas, or uniquely amplified in Las Vegas, result in increased risk to both residents and visitors; selection effects whereby those predisposed to suicide disproportionately choose Las Vegas to reside in and visit; and contagion effects, whereby high numbers of suicides tend to lead to even greater numbers over time, as people emulate the suicides of others. We compare our empirical evidence for each of the effects with existing sociological and historical scholarship on Las Vegas.