Depressive Symptoms after Critical Illness: A Systematic Review and Meta-Analysis

Objectives: To synthesize data on prevalence, natural history, risk factors, and post-ICU interventions for depressive symptoms in ICU survivors. Data Sources: PubMed, EMBASE, Cumulative Index of Nursing and Allied Health Literature, PsycINFO, and Cochrane Controlled Trials Registry (1970-2015). Study Selection: Studies measuring depression after hospital discharge using a validated instrument in more than 20 adults from non-specialty ICUs. Data Extraction: Duplicate independent review and data abstraction. Data Synthesis: The search identified 27,334 titles, with 42 eligible articles on 38 unique studies (n = 4,113). The Hospital Anxiety and Depression Scale-Depression subscale was used most commonly (58%). The pooled Hospital Anxiety and Depression Scale-Depression subscale prevalence (95% CI) of depressive symptoms at a threshold score greater than or equal to 8 was 29% (22-36%) at 2-3 months (12 studies; n = 1,078), 34% (24-43%) at 6 months (seven studies; n = 760), and 29% (23-34%) at 12-14 months (six studies; n = 1,041). The prevalence of suprathreshold depressive symptoms (compatible with Hospital Anxiety and Depression Scale-Depression subscale, ≥ 8) across all studies, using all instruments, was between 29% and 30% at all three time points. The pooled change in prevalence (95% CI) from 2-3 to 6 months (four studies; n = 387) was 5% (-1% to +12%), and from 6 to 12 months (three studies; n = 412) was 1% (-6% to +7%). Risk factors included pre-ICU psychologic morbidity and presence of in-ICU psychologic distress symptoms. We did not identify any post-ICU intervention with strong evidence of improvement in depressive symptoms. Conclusions: Clinically important depressive symptoms occurred in approximately one-third of ICU survivors and were persistent through 12-month follow-up. Greater research into treatment is needed for this common and persistent post-ICU morbidity.