Treatment limitation decision in delirium: a secondary analysis of a prospective observational study.

Background Treatment limitation decision (TLD) is a complex process affected by comorbidities and cultural aspects. We hypothesized that presence of delirium is associated with TLD in hospitalized patients.Objective to compare the proportion of patients with at least one TLD order between delirium and non-delirium patients, to describe factors associated with TLD orders, and to explore the association between TLD, delirium and the 90-day risk of death or hospital readmission.Method All patients admitted to internal medicine at a single hospital between November 2019 and January 2020 had a formal delirium assessment with a neuropsychologist within 48 h of hospitalization. TLD orders, death at 90 days and readmission were recorded.Results 217 patients were included, of whom 119 (54.9%) had a "do not resuscitated" order, 107 (49.3%) had a "do not intubate" order and 77 (35.5%) had a "do not admit to intensive care unit" order. Age, Charlson comorbidity index, cognitive impairment, kidney failure, antidepressant or neuroleptics use, and malnutrition were associated with TLD orders. The presence of at least one TLD order was more common in patients with delirium (24/32 patients, 77.4%) than in patients without delirium (95/185 patients, 51.1%, OR = 3.3 (95%CI: 1.3-8.0); p < 0.01). This association was not significant in the adjusted model (aOR = 2.0; 95%CI: 0.7-5.6; p = 0.20). A TLD order (aHR = 1.8; 95%CI:1.1-3.0.1.0) and delirium (aHR = 1.8; 95%CI:1.1-3.1) were both associated with 90-day hospital readmission or death.Conclusions Patients diagnosed with delirium within 48 h of admission have frequent treatment limitations orders, but the association faints after accounting for comorbidities.