Risk factors for delirium in patients aged 60 years and over with recent myocardial infarction

Abstract Introduction Delirium is a form of acute brain dysfunction and geriatric patients are particularly vulnerable to this health problem. Modifiable and unmodifiable risk factors may influence delirium appearance. Purpose The study aimed to assess the prevalence and characteristic of delirium risk factors in patients ≥ 60 years of age hospitalized due to acute myocardial infarction (AMI). Methods The study included 405 consecutive patients (mean age: 73.1[8.5], males: 248/61.2 %) hospitalized due to AMI divided and characterized according to the in-hospital delirium presence. The following sets of data were analysed: demographic data, length of hospitalization, type of AMI, coronary intervention, multimorbidity, accompanying symptoms, psychiatric conditions, and pharmacotherapy used. Results Of 405 patients, 57 (14%, mean age: 80.9[7.3] years, males: 33/58%) experienced delirium. Patients with delirium were older (80.9[7.3] vs 71.82[8.1] years), all of them presented multimorbidity, they more frequently used polypharmacy (96.5 vs 30.2%) and their hospitalization was longer (8.0[1.4] vs 4.6[1.0] days) as compared to the patients without delirium. Patients with delirium more frequently experience in-hospital reversible problems: periprocedural complications (limited number of radial access, prolonged compression and pain after the procedure, pseudoaneurysm of femoral artery, as well as the following accompanying symptoms: fever (40.4% vs 0.9%), infections (78.9% vs 3.7%), pulmonary oedema (73.7% vs 0.6%), hypoxemia (91.1% vs 98.3%), urinary catheter (96.5% vs 17.2%), dehydration (89.5% vs 6.6%), and insomnia (71.9% vs 0.3%) compared to patients without delirium (Table 1). Delirium was also associated with mild (49.1% vs 0.3%, p<0.0001) and moderate (47.4% vs 9.2%) dementia and symptoms of mild depression (59.6% vs 2.3%) (P<0.0001 for all). Valvular heart disease (OR=4.78; 95%CI: 1.10-2.70; p<0.0001, pulmonary oedema (OR=66.79; 95%CI: 12.04-370.34, p<0.001), and dehydration (OR=37.26; 95%CI: 10.50-132.27, p<0.001) were risk factors for delirium occurrence. Analysis of all factors related to delirium revealed that the coexistence of ≥ 11 concerned 44% of the delirium population (Table 1). Conclusions The in-hospital course of AMI is complicated by delirium occurrence in 14% of patients ≥ 60 years old. Multimorbidity and polypharmacy regard most of the subjects with delirium. The potent reversible complications of the in-hospital course of AMI associated with delirium should be recognized and limited to prevent this problem.Table1.Number of delirium risk factors.