Survival of critical illness in ICU linked to subsequent suicide, self-harm

Compared to hospital survivors who never required ICU admission, those who were discharged from an ICU had a higher risk of suicide and self-harm in a Canadian study. Risk factors included previous psychiatric diagnoses and use of life-support interventions in the ICU.

ICU survivors may be at increased risk for suicide and self-harm behaviors, a recent study found.

The population-based cohort study included consecutive adult ICU survivors in Ontario, Canada, from January 2009 through December 2017. Researchers used linked administrative databases to compare ICU hospital survivors with hospital survivors who never required ICU admission. The primary outcome was the composite of death by suicide, as noted in provincial death records, and deliberate self-harm events after discharge. Results were published online on May 5 by The BMJ.

A total of 423,060 ICU survivors (mean age, 61.7 years; 39% women) were included in the study. During the study period, the crude incidence per 100,000 person-years of suicide, self-harm, and the composite outcome among ICU survivors was 41.4, 327.9, and 361.0, respectively, compared with 16.8, 177.3, and 191.6 in non-ICU hospital survivors. Compared to non-ICU hospital survivors, ICU survivors had a higher risk of suicide (adjusted hazard ratio [HR], 1.22; 95% CI, 1.11 to 1.33) and self-harm (adjusted HR, 1.15; 95% CI, 1.12 to 1.19). Several factors were associated with suicide or self-harm among ICU survivors: previous depression or anxiety (HR, 5.69; 95% CI, 5.38 to 6.02), previous post-traumatic stress disorder (HR, 1.87; 95% CI, 1.64 to 2.13), invasive mechanical ventilation (HR, 1.45; 95% CI, 1.38 to 1.54), and renal replacement therapy (HR, 1.35; 95% CI, 1.17 to 1.56).

Limitations of the study include its observational design and limited granularity of the available data (e.g., drugs received in hospital, mechanism of suicide, initial ICU admission diagnoses, and severity of illness indices), among others, the study authors noted. They added that the self-harm outcome, which was derived as a composite of various ICD codes that were not validated by chart review, only included deliberate self-harm behaviors that prompted medical attention.

The authors noted that the differences in incidence of suicide and self-harm between ICU survivors and non-ICU hospital survivors developed early after discharge and were sustained in the following years. “Therefore, early intervention might be particularly important. … Post-intensive care follow-up clinics could be used to facilitate further identification and treatment of patients with mental health disease after an ICU admission, and could involve consultants in psychiatry or psychology,” they wrote. “Additionally, primary care providers have a fundamental role in assessing and evaluating these patients after ICU and hospital discharge, and early follow-up should be considered.”