Patients who have survived a stay in the intensive care unit (ICU) have a greatly increased risk of developing symptoms of post-traumatic stress disorder (PTSD), according to a new study presented at the 2014 American Thoracic Society International Conference.
"An ICU stay can be traumatic for both patients and their families," said Ann M. Parker, MD, a Pulmonary and Critical Care Medicine fellow at Johns Hopkins University in Baltimore, Maryland. "In our analysis of more than 3,400 ICU patients, we found that one quarter of ICU survivors exhibited symptoms of PTSD." The systematic review of 28 studies involved a total of 3,428 adult ICU survivors. Evaluation included testing with validated PTSD instruments, most commonly the Impact of Events Scale (IES, score range 0-75), administered one month or more after the ICU stay.
In a subset of 429 patients assessed 1-6 months after their stay in the ICU, meta-analysis demonstrated the pooled prevalence of PTSD symptoms was 23% at an IES threshold of ≥35 and 42% at a threshold of ≥20. In 698 patients assessed at 7-12 months, corresponding pooled PTSD prevalence rates were 17% and 34%. Rates in other studies included in the analysis ranged from 5% to 62%.
Risk factors for the occurrence of PTSD symptoms included younger age, use of benzodiazepines and/or mechanical ventilation during the ICU stay, and post-ICU memories of frightening ICU experiences. In some studies of European ICU patients, keeping an ICU diary significantly reduced the occurrence of PTSD symptoms.
Importantly, 3 of 3 studies demonstrated that more PTSD symptoms were associated with worse health-related quality of life.
A potential limitation of this systematic review is the variability of patient populations and PTSD survey instruments studied, which makes direct comparison between studies difficult.
"Our meta-analysis confirms that a large proportion of patients who survive an ICU stay will suffer PTSD symptoms, which are associated with worse health-related quality of life," said Thiti Sricharoenchai, MD, Instructor in the Division of Pulmonary and Critical Care Medicine at Thammasat University, Thailand who conducted this study as a post-doctoral research fellow at Johns Hopkins University. "Further research should focus on PTSD screening, prevention, and treatment in this vulnerable patient population."
Dr. Parker and her mentor, Dr. Dale Needham, Associate Professor of Pulmonary and Critical Care Medicine at Johns Hopkins University, are currently planning a study to evaluate an out-patient intervention to address PTSD symptoms in ICU survivors.