Comparative meta-analysis of prazosin and imagery rehearsal therapy for nightmares, sleep disturbance and post-traumatic stress

Abstract

Introduction The medication, Prazosin, and the psychological treatment known as imagery rehearsal therapy (IRT) have both proven effective for the treatment for post-traumatic stress disorder-associated nightmares.Whereas one recent meta-analysis compares their efficacy for reducing nightmares, their effects on other relevant outcomes, such as sleep quality and post-traumatic stress disorder symptoms (PSS) have not been compared.In this meta-analysis, we compared the short-term efficacy of prazosin and IRT on nightmares, sleep quality and PSS. Materials and methods Reference databases (PubMed, PsycInfo, Google Scholar, Cochrane Library and Web of Knowledge) were searched for studies using IRT or prazosin for nightmares, general sleep disturbance, and/or symptoms of post-traumatic stress.Inclusion criteria were (1) use of a randomized controlled trial design and (2) reporting of treatment outcomes in sufficient detail to calculate effect sizes. Effect sizes (Cohen’s d) were calculated by subtracting the mean post-test score (defined as the first assessment following treatment) in the control group from the mean post-test score in the treatment group, and dividing the result by the pooled standard deviation of both groups. Mixed effects models were performed to evaluate the effect of treatment characteristics on treatment efficacy. Results Fourteen studies with a total of 850 subjects were included.Among these, 3 studies used prazosin, 10 used IRT and 1 included a group of subjects receiving prazosin and a group of subjects receiving IRT. Statistically significant improvements for all IRT comparisons combined (n = 12), and for all prazosin studies combined (n = 4) were found for nightmare frequency (d = 0.55; p 0.01 and d = 0.43; p 0.05, respectively), sleep quality (d = 0.54; p 0.01 and d = 0.70; p 0.01, respectively), and PSS (d = 0.51; p 0.01 and d = 0.69; p 0.01.The difference between the average effect sizes of the IRT studies and those of the prazosin studies was not statistically significant across all three treatment outcomes.However, interventions combining IRT and cognitive-behavioral therapy for insomnia (CBT-I) (n = 3) resulted in greater improvements in sleep quality and PSS than interventions including IRT alone (n = 5) (p 0.05 for sleep quality and p 0.05 for PSS) or IRT combined with other psychological interventions (e.g.lucid dreaming; n = 4: p 0.01 for sleep quality and p 0.05 for PSS). Conclusion Overall, IRT and prazosin have documented and comparable acute effects for the treatment of nightmares, sleep disturbance and PSS. Furthermore, CBT-I seems to be a useful addition to IRT to enhance treatment outcomes. More randomized clinical trials that compare the short- and longer term effects of IRT, prazosin and their combination are warranted. Acknowledgements Fundacion Seneca. Murcia, Spain.