Delirium and Long-term Cognitive Trajectory Among Persons With Dementia

Abstract

Background Delirium is characterized by acute cognitive impairment. We examined the effect of delirium on long-term cognitive trajectory in older adults with Alzheimer's disease (AD). Methods Prospectively collected longitudinal data from a nested cohort of hospitalized patients with AD (n=263) in the Massachusetts Alzheimer's Disease Research Center Patient Registry during 1991–2006 (median follow-up: 3.2 years). Cognitive function was measured using the Information-Memory-Concentration (IMC) section of the Blessed Dementia Rating Scale. Delirium was identified using a validated chart review method. The pace of cognitive deterioration was contrasted using random effect regression models. Results Over half of the sample of patients with AD developed delirium during hospitalization (56%). The pace of cognitive deterioration prior to hospitalization did not differ between patients who developed delirium (1.4 IMC points/year, 95% confidence interval, CI,0.7,2.1) and those who did not (0.8 IMC points/year, 95% CI: 0.3,1.3) (P=0.24). In the year following hospitalization, patients who had developed delirium experienced greater cognitive deterioration (3.1 IMC points/year, 95% CI: 2.1,4.1) relative to patients who did not develop delirium (1.4 IMC points/year, 95% CI: 0.2,2.6) after adjusting for confounders. The ratio of these changes suggests that following delirium, cognitive deterioration proceeds at 2.2 times the rate in patients without delirium in the year after hospitalization. The delirium group maintained a more rapid pace of cognitive deterioration throughout the 5-year period following hospitalization. Sensitivity analyses excluding rehospitalized patients and matching on baseline cognitive function and baseline pace of cognitive deterioration produced essentially identical results. The acceleration due to delirium was independent of dementia severity, comorbidity, and demographic characteristics. Conclusions Delirium is highly prevalent among persons with AD who are hospitalized and associated with an increased pace of cognitive deterioration which is maintained for up to 5 years. Strategies to prevent delirium may offer a promising avenue to explore for ameliorating cognitive deterioration in AD.

Infrared pupillometry helps to detect and predict delirium in the post-anesthesia care unit

“…Delirium, in general, is associated with a worsening of dementia [1], increased hospital costs [2], and increased mortality [3]. Postoperative delirium (POD), occurring in the days to weeks after surgery, has also been linked to cognitive decline and increases in mortality, particularly in elderly patients [4][5][6].…”

Cognitive Dysfunction after Surgery: An Emergent Problem

“…In the SAGES (Successful Aging after Elective Surgery) study, Inouye et al reported biphasic behaviour in patients with and without cognitive decline: major cognitive decline occurred after one month, a comparable recovery of function was observed after two months, but, most importantly, an accelerated decline was observed, in patients, 36 months after anaesthesia or surgery [9]. Gross et al confirm that POCD, following delirium, can accelerate the cognitive decline in Alzheimer's patients [10].…”

Alzheimer’s Disease Legislation And Policy—Now And In The Future

“…For example, a person who was able to function at home but then requires hospitalization because of an injury may experience a persistent reduction in cognitive ability that continues beyond the initial hospitalization. 9 The reduction of preventable hospitalizations or emergency department visits is therefore often cited as an important quality goal for the patient and the health system overall. These quality guidelines remain largely aspirational, however, because of the immense challenges involved in meeting them.…”