Prevalence and risk factors of delirium in psychiatric patients with critical illness

Purpose

Delirium is a serious neuropsychiatric syndrome, which can lead to poor outcomes, especially among patients with critical illness, but is easily missed among psychiatric patients. Some delirium-associated risks have been confirmed for critical patients and psychiatric patients. Nevertheless, the research about delirium in psychiatric patients with critical illness is rare.

Methods

This study aims to investigate the prevalence and risk factors of delirium in psychiatric patients with critical illness. We assessed 425 patients diagnosed with critical illness from Shenzhen Kangning hospital from January 1, 2019, to December 31, 2021, and registered their demographic information, medical history and comorbidities. Patients underwent a psychiatric examination using the Confusion Assessment Method (CAM).

Results

Among the 425 critical illness inpatients, 143 had delirium (prevalence of 33.6%). The most common associations were infectious disease (46.9%), electrolyte disturbance (48.3%), cerebrovascular disease (39.9%), and liver or kidney dysfunction (26.6%). The married status (OR ​= ​3.450, p ​< ​0.001), infectious diseases (OR ​= ​2.862, p ​< ​0.001), electrolyte disturbances (OR ​= ​1.991, p ​= ​0.009) and the organic mental disorder (OR ​= ​5.611, p ​< ​0.001) were independent non-modifiable factors associated with an increased risk of delirium.

Conclusions

According to the study results, the delirium prevalence was about 33%. The organic mental disorder, infectious disease, electrolyte disturbance, cerebrovascular disease, and liver or kidney dysfunction were the risk factors for delirium in psychiatric patients with critical illness. Unexpectedly, the use of olanzapine or haloperidol showed no relevance to delirium.