Delirium linked to tripled dementia risk in older adults, Australian study finds

Trending 2 weeks ago

In a caller study published successful BMJ, researchers explored nan narration betwixt delirium and new-onset dementia among older adults pinch nary dementia test astatine baseline.

​​​​​​​Study: Delirium and incident dementia successful infirmary patients successful New South Wales, Australia: retrospective cohort study. Image Credit: LightField Studios/


Delirium is simply a syndrome marked by inattention and nonaccomplishment of awareness, often caused by acute events specified arsenic sickness aliases surgery. It is predominant successful hospitals, peculiarly among individuals of precocious property pinch superior aesculapian problems.

Delirium is associated pinch adverse outcomes specified arsenic mortality, extended infirmary admissions, and semipermanent cognitive deterioration.

A broad reappraisal and meta-analysis reported an relation of delirium pinch new-onset dementia among individuals without dementia; however, these studies had mini sample sizes and did not relationship for nan important consequence of mortality successful this susceptible population. As nan worldwide dementia load grows, it is captious to place delirium's modifiable consequence factor.

About nan study

The coming study investigated whether delirium is associated pinch new-onset dementia successful older adults utilizing state-level infirmary information linked to nan New South Wales (NSW) Centre for Health Record Linkage.

The researchers conducted nan study from July 2001 to March 2020, extracting information for 650,590 patients aged 65 years and older, excluding those pinch dementia astatine study initiation, arsenic wished utilizing nan International Classification of Diseases, tenth revision (ICD-10) codes. They besides excluded individuals pinch inconsistent information and those aged complete 110 years.

The researchers matched delirium patients 1:1 to patient individuals utilizing objective (e.g., diagnoses and procedures) and individual (e.g., gender, commencement date, nationality, and residence) characteristics and followed them for complete 5 years.

They considered nan follow-up play arsenic nan long betwixt nan scale play (between January 2009 and December 2014) termination and that of nan dataset.

They performed Fine-Gray hazards and Cox proportional hazards and modeling to find nan associations betwixt delirium pinch mortality and new-onset dementia. Study covariates included age, HFRS scores, superior diagnosis, section duration, and intensive attraction portion admittance duration.

The squad calculated infirmary frailty consequence scores (HFRS) and quantified nan dose-response narration betwixt delirium and dementia incidence, stratifying information by sex.

They besides performed sensitivity analyses by extending nan landmark play from a twelvemonth to 2 and repeating analyses aft eliminating individuals who died aliases received a dementia test wrong 2 years of their scale episode.

Results and discussion

The researchers analyzed 55,211 pairs of delirium and non-delirium individuals (48% male, mean property of 83 years). Among nan participants, 63,929 (58%) died, and 19,117 (17%) developed incident dementia successful nan follow-up period.

Individuals pinch delirium showed a 39% accrued consequence of mortality [hazard ratio (HR), 1.4] and a three-fold higher consequence for processing dementia (sub-distribution HR, 3.0) than non-delirium individuals.

Among patients who knowledgeable astatine slightest 1 delirium section successful nan landmark period, each further delirium section related to a 10% accrued decease consequence (HR, 1.1).

The delirium-dementia relation was much robust for males than females (sub-distribution HR, 3.2 vs. 2.9). Each further delirium section was related to a 20% higher new-onset dementia consequence (sub-distribution HR, 1.2).

Sensitivity analyses yielded akin results, indicating nan robustness of nan superior findings. The persistent relationship betwixt delirium beingness and new-onset dementia years aft nan delirium section (and remission of nan triggering stresses) indicated that delirium is much than conscionable an epiphenomenon aliases a motion of undiagnosed dementia aliases a vulnerable brain.

Delirium and dementia person a dose-response association, which whitethorn lead to dementia done geriatric syndromes, aesculapian consequences, and constraints. Delirium whitethorn perchance origin neuronal harm and neurodegeneration by disrupting biologic systems.

The narration betwixt systemic inflammatory indicators, delirium, and dementia is multifaceted and impacted by dementia pathogenesis. Neuroinflammation indicators specified arsenic amyloid-beta (Aβ) and tau proteins are associated pinch some disorders.

The apolipoprotein (APOE) genotype has been linked to delirium, indicating a domiciled for familial profiles associated pinch systemic inflammation. Understanding nan pathophysiological processes of delirium dementia whitethorn lead to nan improvement of innovative therapies to forestall aliases slow neurodegeneration.


The study findings showed that delirium beingness was importantly associated pinch dementia incidence among older individuals pinch nary anterior dementia diagnosis. Patients pinch delirium but without baseline dementia had a three-fold accrued consequence of processing dementia.

The findings bespeak a causal nexus betwixt nan 2 disorders, necessitating nan improvement of caller treatments. The study besides emphasized nan request to see gender erstwhile examining nan narration betwixt delirium and incident dementia. Delirium prevention and curen tin thief little nan world dementia burden.

Men had a greater chance of incident dementia related to delirium, implying a poorer reserve of neuropathology. However, nan narration betwixt neuropathological load and objective dementia is non-linear, and location whitethorn beryllium gender disparities successful neuropathology patterns.

Men whitethorn person much terrible delirium, and location whitethorn beryllium underlying activity differences successful nan molecular underpinnings of delirium that origin encephalon demolition and hastened neurodegeneration. Future investigation should analyse these concepts to observe sex-specific involution targets.

Journal reference:

  • Emily H. Gordon, David D. Ward, Hao Xiong, Shlomo Berkovsky, and Ruth E. Hubbard. (2024) Delirium and incident dementia successful infirmary patients successful New South Wales, Australia: retrospective cohort study, BMJ, doi: