A randomized controlled trial of problem-solving therapy compared to cognitive therapy for the treatment of insomnia in adults.

STUDY OBJECTIVES

To compare the efficacy of problem-solving therapy (PST) combined with behavioral sleep strategies to standard cognitive therapy (CT) combined with behavioral sleep strategies in the treatment of insomnia.

DESIGN

A six-week randomized controlled trial with one month follow-up.

SETTING

The Australian National University Psychology Clinic, Canberra, Australia.

PARTICIPANTS

Forty-seven adults aged 18-60 years recruited from the community meeting the Research Diagnostic Criteria for insomnia.

INTERVENTIONS

Participants received 6 weeks of treatment including one group session (sleep education and hygiene, stimulus control instructions and progressive muscle relaxation) followed by 5 weeks of individual treatment of PST or CT.

MEASUREMENTS AND RESULTS

Primary outcomes included sleep efficiency (SE) from sleep diaries, the Insomnia Severity Index (ISI), and the Pittsburgh Sleep Quality Index (PSQI). Secondary measures assessed dysfunctional sleep beliefs, problem-solving skills and orientations, and worry. Both treatments produced significant post therapy improvements in sleep which were maintained at 1 month follow-up (on SE Cohen d = 1.42, 95% CI 1.02-1.87 for PST; d = 1.26, 95% CI 0.81-1.65 for CT; on ISI d = 1.46, 95% CI 1.03-1.88 for PST; d = 1.95, 95% CI 0.52-2.38 for CT; for PSQI d = 0.97, 95% CI 0.55-1.40 for PST and d = 1.34, 95% CI 0.90-1.79 for the CT). There were no differences in PST and CT in the size or rate of improvement in sleep although CT produced a significant faster rate of decline in negative beliefs about sleep than PST and there was a trend (P = 0.08) for PST to produce a faster rate of improvement in negative problem orientation than CT.

CONCLUSIONS

The results provide preliminary support for problem solving treatment as an equally efficacious alternative component to cognitive therapy in psychological interventions for insomnia.