Gastrointestinal Dysfunction: Diagnostic Categories, Prevalence, and Associated Conditions

Abstract

Sleep dysfunction is associated with a wide range of chronic conditions. Insomnia, the most prevalent of all reported sleep problems, is estimated to occur in between 20 percent and 40 percent of adults within the general population and is even more prevalent among individuals with chronic illness and impairments (Morin 1993). Excessive daytime sleepiness, which involves daytime sleep episodes at inappropriate and unexpected times, is estimated to occur in 12 percent of the general population and to result in significant cognitive, emotional, and accident-risk consequences (Happe 2003). Excessive daytime sleepiness may accompany a wide range of sleep disorders, including narcolepsy and various forms of insomnia. One study found that over half of individuals with severe insomnia reported two or more heath problems during a past 12-month period (Mellinger, Balter, and Uhlenhuth 1985). A second longitudinal study reported a strong association between poor health status among aging subjects and severe sleep dysfunction (Rodin, McAvay, and Timko 1988). Some suggest that the physical symptoms reported by individuals with chronic sleep dysfunction tend to be nonspecific and indicative of underlying stress, depression , or anxiety. For example, one study found that individuals with sleep dysfunc-tion tend to report gastrointestinal problems, generalized aches and pains, tension headaches, and allergies (Kales et al., 1984). Other studies have found that individuals with sleep dysfunction tend to be more preoccupied with their health (Ford and Kamerow 1989; Kales et al., 1984; Morgan et al., 1988). One study found that sleep problems were twice as prevalent in men that regularly sought medical care as compared with those that did not regularly seek care (Gislason and Almqvist 1987). There are a number of potential explanations for these observed linkages between sleep dysfunction, help-seeking behavior, and an increased number of health complaints. These include the possibility of a physiological basis for sleep dysfunction, the possibility of a psychological basis for sleep dysfunction, and the possibility of a combined physiological and psychological basis for sleep dys-function. The extent to which physiological versus psychological variables contribute to a given sleep problem likely varies depending on the nature of the role of sleep in the specific condition under consideration. 279