Insomniacs' reported use of CBT components and relationship to long-term clinical outcome

Abstract

Although there is considerable evidence for the efficacy of non-pharmacological treatment of insomnia, many of the larger trials have delivered CBT in multicomponent format. This makes it impossible to identify critical ingredients responsible for improvement. Furthermore, compliance with home implementation is difficult to ascertain in psychological therapies, and even more so when trying to differentiate across a range of elements. In the present report, 90 patients who had completed 12 month follow-up after participation in a clinical effectiveness study of CBT in general medical practice, responded to a questionnaire asking them about their use of the ten components of the programme. Reports of home use were then entered as predictors of clinical response to treatment. Results indicated that reported home use of stimulus control/sleep restriction was the best predictor of clinical improvement in sleep latency and nighttime wakefulness. Cognitive restructuring also contributed significantly to reduction in wakefulness. In spite of being the most highly endorsed component (by 79% of respondents) use of relaxation did not predict improvement on any variable. Similarly, sleep hygiene was unrelated to sleep pattern change and use of imagery training was modestly predictive of poor response in terms of sleep latency. There are methodological limitations to this type of post hoc analysis, nevertheless, these results being derived from a large patient outcome series raise important issues both for research and clinical practice.

Introduction

It is difficult to gauge the extent to which patients comply with cognitive behavioural treatment (CBT). Generally, such interventions rely upon home practice and there is no objective criterion by which compliance can be measured. Beneficial effects, either within or between treatments, therefore, could be accounted for simply in terms of patterns of implementation and/or perceived credibility. On the other hand, there may be no a priori reason to suspect that acceptability varies amongst treatments. Early research on insomnia, comparing single component interventions such as stimulus control, relaxation and paradoxical intention, suggested that these treatments were equally credible, in terms of therapeutic rationale (Turner & Ascher, 1979, Espie, Lindsay, Brooks, Hood, & Turvey, 1989), although sleep hygiene education may be less so (Schoicket, Bertelson, & Lacks, 1988). There is very limited evidence on compliance. In a recent influential study, patients and significant others reported similarly high levels of compliant behaviour on a rating scale measure across CBT and pharmacological treatments, and urine screens supported their reports in terms of benzodiazepine use (Morin, Colecchi, Stone, Sood, & Brink, 1999). However, some work on relaxation therapies, using discreet counters in audiocassette machines, does suggest that people over-report home practice (Lichstein & Hoelscher, 1986). Therefore, although chronic insomniacs of all ages appear to find CBT credible and even older adults are generally accepting of a psychological approach (Morin, Gaulier, Barry, & Kowatch, 1992), we do not really know how this translates into action.

These issues are compounded by the clinical practice of multicomponent CBT delivery. Systematic comparisons of single components are more typical of efficacy studies, whereas ‘package’ treatments reflect clinical practice (Chesson et al., 1999). Recent commentaries on non-pharmacological treatments of insomnia have stressed the importance of research leading to the identification of critical ingredients in therapy (Morin et al., 1999, Edinger & Wohlgemuth, 1999). This would be valuable not only conceptually by suggesting possible mechanisms of effect, but also practically, in terms of the cost-efficient use of scarce resources and an understanding of the ‘dose–response’ relationship for psychological practice.

We have recently reported outcome data from a large clinical effectiveness study using multicomponent CBT for insomnia. Our results demonstrate significant and sustained improvements in sleep pattern and sleep quality at one year follow-up, with average reductions in sleeplessness of around 60 min per night (Espie, Inglis, Tessier, & Harvey, 2001). Up to two-thirds of our patients no longer met criteria for insomnia at one year, and 40% had reduced sleep latency and wakeful time in bed after sleep-onset by at least 50%. Over 80% of those previously on sleeping pills had stopped taking them, and patients reported finding CBT highly credible (Espie, Inglis, & Harvey, 2001). Importantly, these outcomes were obtained across the full range of clinical presentation, and were not contraindicated by factors such as severity of insomnia, associated psychopathology or use of sleep medication. Although our study was not designed to tease out treatment component effects, we do have data which permit quantification of patients' self-reported home use of elements of the programme, and we are able to compare reported use of these components between treatment ‘responders’ and ‘non-responders’ at 1 yr follow-up.