Risk factors for post-traumatic stress disorder symptoms in surrogate decision-makers of patients with chronic critical illness

Rationale: Chronically critically ill patients are often dependent on family members for surrogate decision-making, and these surrogates are at high risk for emotional distress. We hypothesized that patient- and surrogate-specific risk factors for surrogate post-traumatic stress disorder (PTSD) symptoms can be identified early in the course of chronic critical illness. Objectives: To identify risk factors for PTSD symptoms in surrogate decision-makers of chronically critically ill patients. Methods: We performed a secondary analysis of the database from a multicenter randomized trial of a communication intervention for chronic critical illness patients and surrogates. Variables preselected for plausible mechanism for increasing PTSD symptoms and identifiable by Day 10 of mechanical ventilation were included in the analysis for association with surrogate PTSD symptoms at 90 days, as measured by the Impact of Events Score-Revised (IES-R). Patient factors included demographics, insurance status, baseline functional status, chronic comorbidities, illness severity, and presence of advance directive. Surrogate variables included demographics, education level and employment, religion, relationship to patient, and Hospital Anxiety and Depression Scale score measured at enrollment. Multivariable linear regression models were then constructed for 26 potential risk factors, including biologically or mechanistically plausible confounders for each, with IES-R score as the outcome. All models were adjusted for multiple respondents, using a mixed model, considering the patients as a random factor. Results: Our analysis included 306 surrogates for 224 patients. A total of 49% of patients were female, and mean age was 59 years (95% confidence interval [CI], 56.4-60.7). A total of 71% of surrogates were female, and mean age was 51 years (95% CI, 49.3-52.4). After examining each potential risk factor in a separate multivariable model, only Day-10 surrogate Hospital Anxiety and Depression Scale score (b coefficient = 1.02; 95% CI, 0.73-1.30) and patient unresponsiveness (b coefficient = 8.39; 95% CI, 0.83-15.95) were associated with higher IES-R scores. Conclusions: Among surrogate decision-makers for chronically critically ill patients, high anxiety and depression scores and patient unresponsiveness on or near Day 10 of mechanical ventilation are risk factors for PTSD symptoms at 90 days.