Estimates of Geriatric Delirium Frequency in Noncardiac Surgeries and Its Evaluation Across the Years: A Systematic Review and Meta-analysis.

OBJECTIVES: Delirium is an acute neuropsychiatric syndrome associated with poor outcomes. Older adults undergoing surgery have a higher risk of manifesting perioperative delirium, particularly those having associated comorbidities. It remains unclear whether delirium frequency varies across surgical settings and if it has remained stable across the years. We conducted a systematic review to (1) determine the overall frequency of delirium in older people undergoing noncardiac surgery; (2) explore factors explaining the variability of the estimates; and (3) determine the changing of the estimates over the past 2 decades. DESIGN: Systematic review and meta-analysis. Literature search was performed in MEDLINE, PubMed, ISI Web of Science, EBSCO, ISRCTN registry, ScienceDirect, and Embase in January 2020 for studies published from 1995 to 2020. SETTING: Noncardiac surgical settings. PARTICIPANTS: Forty-nine studies were included with a total of 26,865 patients screened for delirium. METHODS: We included observational and controlled trials reporting incidence, prevalence, or proportion of delirium in adults aged ≥60 years undergoing any noncardiac surgery requiring hospitalization. Data extracted included sample size, reported delirium frequencies, surgery type, anesthesia type, delirium diagnosis method, length of hospitalization, and year of assessment. (PROSPERO registration no.: CRD42020160045). RESULTS: We found an overall pooled frequency of preoperative delirium of 17.9% and postoperative delirium (POD) of 23.8%. The POD estimates increased between 1995 and 2020 at an average rate of 3% per year. Pooled estimates of POD were significantly higher in studies not excluding patients with lower cognitive performance before surgery (28% vs 16%) and when general anesthesia was used in comparison to local, spinal, or epidural anesthesia (28% vs 20%). CONCLUSIONS AND IMPLICATIONS: Type of anesthesia and preoperative cognitive status were significant moderators of delirium frequency. POD in noncardiac surgery has been increasing across the years, suggesting that more resources should be allocated to delirium prevention and management.

Arousal changes and delirium in acute medically-ill male older patients with and without dementia: a prospective study during hospitalization.

Objectives: Previous research has characterized the prevalence, natural course and outcomes of delirium superimposed in dementia but much less is known about the relation between preexisting dementia and the emergence of altered arousal (such as drowsiness, obtundation, stupor or agitation) during acute medical illness. This study aimed to determine the natural course of delirium and abnormal arousal states in acute medically-ill older patients with and without prior dementia during hospital stay.Methods: Observational prospective study in an acute male geriatric ward. Patients aged ≥ 65 years old were assessed by a psychiatrist within the first 72h of admission and in every other day until discharge to determine the level of arousal and the presence of delirium. Prior cognitive impairment, sociodemographic data, chronic comorbidities, psychotropic prescription and functional status were assessed at baseline.Results: 43.5% of participants in the final sample (n= 269) had dementia. Prior dementia was associated with higher rates of moderate/severe hypoarousal (29.9% vs. 4.6%; p<0.001) and delirium (20.5% vs. 7.2%; p<0.001) at admission. RASS ≤ -3 at admission predicted a 4-fold increased intra-hospital mortality risk and RASS ≠ 0 had a sensitivity of 82.8% and a specificity of85.9% for delirium.Conclusions: Moderate/severe hypoarousal is associated with adverse outcomes and should be assessed as part of delirium spectrum, particularly in subjects with prior dementia.

Delirium Induced by Quetiapine and the Potential Role of Norquetiapine.

Quetiapine in an atypical antipsychotic drug that is frequently used for delirium and behavioral and psychological symptoms in dementia. However, its potential anticholinergic effects, mediated primarily through its metabolite norquetiapine, could present as counterproductive adverse effects in these situations. There is little data published discussing this potential negative impact on quetiapine's safety and tolerability, especially in the elderly. Here, we present what is, to our knowledge, the first published case report of delirium apparently induced by low-dose quetiapine, in a 95-year-old patient with no prior history of mental illness, and the potential role of its metabolite norquetiapine.