Longitudinal Changes in Symptoms of Post-Intensive Care Syndrome: A Secondary Analysis of a Scoping Review

Since the increased interest in post-intensive care syndrome (PICS) and PICS-family, many studies have been conducted. However, the longitudinal changes in PICS symptoms are not clearly understood. This study aimed to summarize the longitudinal symptom changes in each PICS domain, including physical, cognitive, mental health, quality of life, and family.

In this secondary analysis study, we identified the studies that conducted longitudinal PICS assessments published between 2014 and 2022. The most frequently used assessment tools in each domain were defined as representative methods, and results of included studies were summarized by each PICS domain. The collected data were grouped by the following: within 3 months (baseline), at 3 months, 6 months, and annually thereafter. The Wilcoxon rank-sum test was used to compare changes from baseline.

Of the 5,160 studies screened, 76 studies were selected in this study. The percentage predicted value of the 6-minute walk test as an indicator of physical function significantly improved from baseline to 6 months (median [interquartile range], from 45.9 [32.0-63.0] to 65.0 [57.8-72.8], p = 0.04), and continued to improve during the 5-year follow-up period. Montreal Cognitive Assessment for cognitive assessment and Impact of Event Scale-Revised for mental health assessment did not show statistically significant change. The anxiety score of the Hospital Anxiety and Depression Scale (HADS) improved from baseline to the 12-month follow-up (from 6.8 [4.0-8.5] to 4.3 [3.3-5.3], p = 0.04). The anxiety and depression scores of the HADS in family members did not show statistically significant change. The physical component summary of the Short Form-36 for quality of life assessment increased from baseline to the 12-month follow-up (from 31.3 [25.5-37.1] to 40.6 [36.9-50.0], p = 0.03); however, the mental component summary of the Short Form-36 was not changed with statistical significance.

Although the physical and mental domains showed significant longitudinal improvements, PICS symptoms were long-lasting in all domains with varying severity.