Efficacy Study of Mindfulness-Based Exercise for Posttraumatic Stress Disorder (PTSD)

Not Applicable

Completed

Brief Summary: This study will explore the relationship between changes in plasma cortisol and symptom reduction resulting from individuals with posttraumatic stress disorder (PTSD) participating in an 8-week program of mindfulness-based stretching and breathing exercise. The investigators hypothesize that at the completion of participation in the 8-week program, exercise-induced symptom reduction will be associated with changes in cortisol levels.

Detailed Description: This study will employ an intent-to-treat design to evaluate the relationship between exercise-induced posttraumatic stress disorder (PTSD) symptom reduction and exercise-induced changes in cortisol level. The participants consist of nurses and the intervention will be conducted at the Clinical and Translational Science Center of the University of New Mexico. The study was approved by the Human Research Protections Office of the university. Nurses who are screened positively for PTSD will be randomly assigned to either control or exercise group. At baseline and in weeks 4, 8, 12 and 16, immediately after the phlebotomy for serum cortisol, the investigators will ask the participants to rate the severity of their PTSD symptoms using the PTSD Checklist (PCL).

Recruitment & Eligibility

Inclusion Criteria

employed as a nurse
PCL-C score of at least 28 with at least a score of 3 on one or more items for inclusion in the PTSD symptomatic groups (EX and CON)
PCL-C score of 27 or lower for inclusion in the non-PTSD symptomatic group (BASE).

Exclusion Criteria

the inability to complete the exercise program
a positive answer to any of the seven screening questions on the Physical Activity Readiness Questionnaire (PAR-Q)
current use of prednisone or other forms of cortisone medication excluding cortisone in inhaled form

Arm && Interventions

Group	Intervention	Description
Exercise Group	Mindfulness-based exercise	Participants who are screened positive for PTSD and participate in the series of 16 standardized, semiweekly 60-minute mindfulness-based exercise sessions. The intervention consists of stretching and balancing movements combined with breathing and a focus on mindfulness.Over the course of 8 weeks, the intensity of the exercise increases, but the sequence of the movements is the same.

Primary Outcome Measures

Name	Time	Method
Change From Baseline in PTSD Checklist - Civilian Version (PCL-C) Score	Baseline and 8 weeks	The PCL-C is a 17-item self-report instrument that measures the symptoms of PTSD. A total score, ranging from 17 to 85, is found by summing the scores of the 17 items. Higher values are considered to be a worse outcome. The inclusion criteria in the PTSD symptomatic group is a PCL-C total score of at least 28 with a score of 3 or higher on 1 or more items.To detect a reduction in PTSD symptom severity with a 2-sided 5% significance level and a power of 80%, the mean difference of PCL-C scores of 5.16 or greater requires a sample size of 20 participants for Exercise and Control groups, given an anticipated dropout rate of 10%. Data analyses are conducted using an a priori intention-to-treat approach. The analysis for the between-group differences of the intervention is conducted using t-tests comparing Exercise and Control groups at post-intervention. The analysis for the within-group difference is conducted using repeated measures ANOVA for both groups at baseline and week 8.

Secondary Outcome Measures

Name	Time	Method
Cortisol	baseline and 8 weeks	Change from baseline in serum cortisol levels at 8 weeks. Serum cortisol samples were collected at 8:00 Ante Meridian (AM). The changes are calculated from two time points as the values at 8 weeks minus the values at baseline.