More than most disruptive habits, problem gambling tends to be an after-dark activity. The quiet anonymity of the evening hours seems to appeal to gamblers who feel the need to hide their behavior from the scrutiny of friends and family. But there is another important factor at work. Compulsive gamblers often get so wrapped in their wagering that they lose all track of time. They become oblivious to the hours melting away as they chase losses, desperately trying to get back into the black. The owners and operators of casinos understand this all too well, which is why gambling houses never have clocks or windows. When it comes to the passage of time, gambling operators prefer to keep their customers in the dark, both figuratively and literally. Because gamblers are night owls, it is easy to postulate that sleep deprivation and insomnia must be a common problem for many. Surprisingly, however, this theorized connection between problem gambling and sleep deprivation has not been the subject of extensive study. This is unfortunate because the dynamics of comorbid conditions (when two or more disorders manifest simultaneously) are complex and their interrelationships can complicate the treatment of one disorder or the other. For example, studies into the relationship between sleep disorders and substance abuse have shown that cause-and-effect processes play both sides against the middle. Drug and alcohol abuse are, in some instances, a coping mechanism for those suffering from insomnia, while substance abuse increases the incidence of sleeping disorders. The two problems tend to reinforce each other, and as a result treating one disorder without acknowledging or treating the other is likely to be an exercise in futility. More study needs to be done to determine how compulsive gambling and gambling addiction might aggravate\u2014and be aggravated by\u2014sleep deprivation and insomnia. But the data cupboard on this question isn\u2019t entirely bare. Partners in Crime: Compulsive Gambling and Insomnia In the February 2012 edition of the Journal of Addictive Diseases, a UCLA research team published the results of a survey they conducted on compulsive gambling and sleeping disorders. They recruited 120 non-treatment-seeking gamblers to participate in their study, each of whom expressed at least some concern about their ability to control their betting and wagering behavior. None of these volunteers was screened ahead of time for a sleep disorder. To determine the extent of their gambling problems, each individual was evaluated using criteria listed in the most recent edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). After 24 individuals were dismissed because they had not gambled recently, the remaining 96 volunteers were classified into one of three groups: recreational (non-problem) gamblers (23 participants), problem gamblers (37) and pathological gamblers (36). They were all then tested for sleep disorders using two clinically accepted evaluation tools: the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS). Scores above five on the PSQI are associated with poor sleep quality, and anyone who scores above 10 on the ESS is assumed to suffer from significant daytime sleepiness. Cross-referencing showed no noticeable sleeping issues for the gamblers assigned to the recreational category. The members of this group scored 3.35 on the Pittsburgh scale and 4.13 on the Epworth scale, putting them well within the range of average. Problem gamblers didn\u2019t do badly on the ESS either, registering an average score of 5.81, which would be consistent with relatively small amounts of daytime sleepiness. But both problem gamblers and pathological gamblers tested positive for insomnia on the PSQI scale, coming in with scores of 5.30 and 5.44 respectively. Pathological gamblers were edging toward trouble on the Epworth Sleepiness Scale as well, registering an average score of 8.69. So a clear connection between heavy, habitual gambling and sleep disturbance was established by the findings of this study. In fact, the link was strong enough to indicate that many compulsive gamblers might need intervention for their sleeping difficulties as well as their gambling issues if they are to be expected to make a full recovery from either condition. Sleep Troubles Could Mean Real Trouble for Problem Gamblers This research project was not designed to establish a cause-and-effect relationship between problem gambling and sleep troubles, or vice versa. Comorbid conditions are normally assumed to interrelate and strengthen each other, however, so the presence of sleeping disorders in problem or pathological gamblers is not a situation to be taken lightly. The sponsors of the UCLA study point out that gambling addiction frequently co-occurs with mood disorders, anxiety disorders and substance abuse problems, and each of these conditions will exacerbate and be exacerbated by sleep disorders. Additionally, other studies have shown that sleep disturbances are associated with poor decision-making, reduced risk aversion and a lack of impulse control, all of which are implicated in compulsive, habitual gambling. Even though more research into the specific aspects of the gambling-insomnia connection is needed, addiction specialists working with pathological and problem gamblers should be screening for sleep disorders and taking the results of those tests very seriously as they forge their treatment plans.