Sleep problems among persons with a lifetime history of posttraumatic stress disorder alone and in combination with a lifetime history of other psychiatric disorders: a replication and extension.

OBJECTIVE

Sleep problems are a clinical and/or diagnostic feature for a broad array of mood, substance use, and anxiety disorders, including posttraumatic stress disorder (PTSD). Previous research by Leskin et al (Leskin GA, Woodward SH, Young HE, Sheikh J. Effects of comorbid diagnoses on sleep disturbance in PTSD. J Psychiat Res 2002;36:449-452) using the baseline National Comorbidity Survey (NCS) data found that persons with PTSD and panic disorder had a greater proportion of sleep problems than persons with other comorbid disorders. The current study extends Leskin et al's findings using the replication of the NCS. It compared persons with a lifetime history of PTSD (either alone or in combination) with 6 comparison disorders (adult separation anxiety, alcohol dependence, generalized anxiety, dysthymia, major depression, and panic) on severity of sleep disorder symptoms.

METHOD: The NCS Replication was a national probability survey of 9282 individuals that examined the prevalence and correlates of mental disorders. Subjects were chosen through a multistage probability sample of US households and interviewed using a computer-aided version of the Composite International Diagnostic Interview.

RESULTS

The PTSD (alone) group did not differ from the comparison disorders on difficulties of falling/staying asleep but did report more weeks per year when they had sleep difficulties than persons with adult separation anxiety, alcohol dependence, and major depression.

CONCLUSION

Unlike Leskin et al, the additive effects of a second disorder on sleep difficulties are not unique to panic disorder. However, when sleep difficulties were indexed by the number of weeks per year, differences between diagnostic groups emerged. If the goal of a diagnostic system is to carve nature at its joints, a sleep disturbance symptom reflecting frequency of difficulties in this way is clearly superior to less precise alternatives.