Postoperative delirium is associated with grey matter brain volume loss

Abstract

Delirium is associated with long-term cognitive dysfunction and with increased brain atrophy. However, it is unclear whether these problems result from or predispose to delirium. We aimed to investigate preoperative to postoperative brain changes, as well as the role of delirium in these changes over time. We investigated the effects of surgery and postoperative delirium with brain MRIs made before and three months after major elective surgery in 299 elderly patients, and an MRI with a three months follow-up MRI in 48 non-surgical control participants. To study the effects of surgery and delirium, we compared brain volumes, white matter hyperintensities, and brain infarcts between baseline and follow-up MRIs, using multiple regression analyses adjusting for possible confounders. Within the patients group, 37 persons (12%) developed postoperative delirium. Surgical patients showed a greater decrease in grey matter volume than non-surgical control participants (linear regression: B (95% Confidence Interval) = -0.65% of intracranial volume (-1.01 to -0.29, p < 0.005). Within the surgery group, delirium was associated with a greater decrease in grey matter volume (B (95% Confidence Interval): -0.44% of intracranial volume (-0.82 to -0.06, p = 0.02). Furthermore, within the patients, delirium was associated with a non-significantly increased risk of a new postoperative brain infarct (logistic regression: odds ratio (95% Confidence Interval): 2.8 (0.7 to 11.1), p = 0.14). Our study was the first to investigate the association between delirium and preoperative to postoperative brain volume changes, suggesting that delirium is associated with increased progression of grey matter volume loss.

Structural disconnectivity in postoperative delirium: A perioperative two‐center cohort study in older patients

“…We have shown that episodes of POD might be detrimental for white matter integrity. Together with the loss of gray matter volume after episodes of POD, 36 our findings could represent the structural correlate of worsening cognitive trajectories in POD patients. 37 Future studies need to investigate whether this white and gray matter depletion after episodes of delirium may lead to cognitive decline and eventually the development of dementia.…”

How to manage catatonia, Parkinson and dementia in ICU

“…impaired blood flow and tissue perfusion). These pathways may contribute to increased progression of grey matter volume loss and long-lasting decreased brain functional connectivity that were observed after delirium [45 ▪ ,46 ▪ ].…”

Postoperative Delirium and the Older Adult: Untangling the Confusion

“…20,21 Preoperative cortical brain infarcts, complex white matter hyperintensity, brain atrophy, and glymphatic system changes are examples of brain areas that could be used as surrogate markers for brain vulnerability. 22,23 In addition, hypointense areas in the cholinergic system were related to POD, possibly representing areas of iron deposition and calcifications, also seen in a range of neurodegenerative diseases. 24 Challenges such as diagnostic assessment method, frequency of evaluation, and constraints related to the collection of biomarkers all make this task difficult.…”

“…Other promising biomarkers relate to imaging studies, some of which have identified specific brain lesions that might predispose at-risk populations for developing POD 20,21 . Preoperative cortical brain infarcts, complex white matter hyperintensity, brain atrophy, and glymphatic system changes are examples of brain areas that could be used as surrogate markers for brain vulnerability 22,23 . In addition, hypointense areas in the cholinergic system were related to POD, possibly representing areas of iron deposition and calcifications, also seen in a range of neurodegenerative diseases 24 …”