Association of serum brain-derived neurotrophic factor (BDNF) and tumor necrosis factor-alpha (TNF-α) with diagnosis of delirium in oncology inpatients

Abstract

Objective: To evaluate brain-derived neurotrophic factor (BDNF) and tumor necrosis factor-a (TNF-a) blood levels as disease biomarkers of delirium in oncology inpatients. Methods: Seventeen oncology inpatients with delirium, 28 oncology inpatients without delirium, and 25 non-oncology controls (caregivers) were consecutively recruited from a Brazilian cancer center. This sample was matched by age, sex, and education level. The Confusion Assessment Method, the Mini-Mental State Examination, and the Digit Span Test were administered to ascertain delirium diagnosis. BDNF and TNF-a levels were measured by the Sandwich-ELISA method and flow cytometry, respectively. Blood samples were collected immediately after clinical evaluation. Results: Oncology inpatients (with and without delirium) showed significantly lower BDNF levels compared with non-oncology controls (F = 13.830; p = 0.001). TNF-a levels did not differ between the three groups. Conclusion: A cross-sectional relationship of BDNF and TNF-a blood levels with delirium in oncology inpatients was not demonstrated. The association between cancer and reduced serum BDNF levels may be mediated by confounding factors.

The Association of Serum Levels of Brain-Derived Neurotrophic Factor with the Occurrence of and Recovery from Delirium in Older Medical Inpatients

“…A study in ICU patients [ 16 ] found that serum BDNF levels were significantly higher in delirious patients compared to nondelirious controls. In contrast, a study in oncology inpatients [ 17 ] did not find any significant differences in the serum levels of BDNF between delirious and nondelirious patients. Similarly, Tomasi et al [ 18 ] in a study of community-acquired pneumonia found that patients “with sepsis-associated encephalopathy (SAE)” had higher levels of BDNF compared to “delirious patients.” Another study examining outcomes in ICU patients reported that low levels of BDNF were associated with increased mortality [ 19 ].…”

Epigenetics of Delirium and Aging: Potential Role of DNA Methylation Change on Cytokine Genes in Glia and Blood Along With Aging

“…In fact, relationship between direct measurement of TNF-alpha level and delirium has been controversial. In patients with delirium, multiple study reported that TNF-alpha remain not significant (De Rooij et al, 2007 ; Çinar et al, 2014 ; Brum et al, 2015 ). Of note, sample sizes of delirium cases in these reports are less than 100 (64 cases, 15 cases, and 17 cases, respectively), thus the result might have been underpowered.…”

Delirium and Alzheimer disease: A proposed model for shared pathophysiology

“…Others have observed that at early stages of AD, BDNF significantly increased in comparison to control groups although levels then declined in later stages of the disease whereas another study found no change in BDNF 42 . BDNF has been found to be elevated in delirium in one study 28 and not elevated compared with controls in another study 43 . BDNF has not yet been studied as a resilience factor following an episode of delirium, which would correspond to its putative physiological role.…”

“…41 BDNF has been found to be elevated in delirium in one study 27 and not elevated compared with controls in another study. 42 BDNF has not yet been studied as a resilience factor following an episode of delirium, which would correspond to its putative physiological role.…”