Does Exposure To Gambling Lead To More Problems?

When a new opportunity to gamble – whether a casino, the lottery or other forms of gambling – comes into a community, assumptions swirl around about whether or not the rate of disordered gambling will increase. Does exposure to gambling opportunities pose a risk to our health and increase the rate of gambling problems in a community?

Conventional wisdom assumes that the expansion of lotteries, casinos, Internet gambling and other forms of gaming will result in an increased rate of gambling disorders. One advocate of the exposure model predicted in 1994 that “when gambling activities are legalized, economies will be plagued with 100% to 550% increases in the numbers of addicted gamblers (probably within one to five years, but almost certainly within fifteen years).”1

This prediction, however, has not been borne out by the research conducted over the past 35 years. National surveys of gambling problems in the U.S. conducted in 1977 and 2008 found the same rate of 1% –in spite of the massive expansion of legalized gambling in the U.S. during this period.2,3Prevalence rates have remained stable in other countries as well, including Switzerland which has experienced widespread openings of casinos over the past decade.4

Harvard Medical School researchers have proposed the theory of ‘adaptation’ to account for the stability of prevalence rates. They suggest that, ‘following initial increases in the number and types of adverse reactions to new and novel social opportunities (e.g., substance use, gambling), people will adapt gradually and become more resistant to those events, eventually leading to stable or lower prevalence rates.’5(p621)

In other words, when a new gambling opportunity comes to town, the prevalence rate of gambling disorders might initially increase slightly. Researchers surmise that it is the “novelty effect of a new form of gambling. But, over time, the “novelty” wears off and prevalence rates of gambling disorders fall back to the 1% level.

The Harvard researchers found evidence for the adaptation theory in a study of Nevada, the state in the U.S. most exposed to gambling in terms of both gambling opportunities and employment in gaming operations. The Volberg study6used two instruments to measure the prevalence of gambling disorders in Nevada: theSouth Oaks Gambling Screen (SOGS)7and theNORC DSM-IV Screen for Gambling Problems (NODS).8The SOGS, known for reporting false positives, found a rate of gambling problems higher than the national average found by Kallick in 1979.2However, the NODS instrument reported rates that were half of those reported for the nation one year earlier when the same instrument was used, providing support for the adaptation model. Moreover, the Nevada study found that newer residents had higher rates of gambling problems than residents who had lived in the state for 10 or more years.6

A more recent test of the adaptation theory comes from Iowa. A survey conducted by Black et al. found that gambling participation had decreased since 1995, and the prevalence rate of gambling disorders had remained stable despite the continuing proliferation of casinos and other gambling opportunities.9The authors concluded that the results confirm the adaptation hypothesis.

Do these findings square with your experience? Share your comments below.


1. Kindt J. The economic impacts of legalized gambling activities.Drake Law Rev. 43:51–95.

2. Kallick M, Suits D, Dielman T, Hybels J.A Survey of American Gambling Attitudes and Behavior. Ann Arbor: University of Michigan Press; 1979.

3. Kessler RC, Hwang I, LaBrie R, et al. DSM-IV pathological gambling in the National Comorbidity Survey Replication.Psychol Med. 2008;38(9):1351–60. doi:S0033291708002900 [pii] 10.1017/S0033291708002900.

4. Bondolfi G, Jermann F, Ferrero F, Zullino D, Osiek C. Prevalence of pathological gambling in Switzerland after the opening of casinos and the introduction of new preventive legislation.Acta Psychiatr Scand. 2008;117(3):236–239. doi:10.1111/j.1600-0447.2007.01149.x.

5. LaPlante DA, Shaffer HJ. Understanding the influence of gambling opportunities: Expanding exposure models to include adaptation.Am J Orthopsychiatry. 2007;77(4):616–623.

6. Volberg R.Gambling and Problem Gambling in Nevada. Northampton, MA: Gemini Research Ltd.; 2002.

7. Lesieur HR, Blume SB. The South Oaks Gambling Screen (SOGS): A new instrument for the identification of pathological gamblers.Am J Psychiatry. 1987;144(9):1184–8. Available at:

8. Gerstein D, Murphy S, Toce M, et al.Gambling Impact and Behavior Study: Report to the National Gambling Impact Study Commission. Chicago: National Opinion Research Center; 1999.

9. Black DW, McCormick B, Losch ME, Shaw M, Lutz G, Allen J. Prevalence of problem gambling in Iowa: Revisiting Shaffer’s adaptation hypothesis.Ann Clin Psychiatry Off J Am Acad Clin Psychiatr. 2012;24(4):279–284.

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