Cancer survivors have a lower frequency of dementia in the 95+ oldest‐old. (31st December 2021)

• Record Type: Journal Article
• Authors: Lachner, Christian; Camsari, Gamze Balci; Ertekin‐Taner, Nilufer; Thompson, E. Aubrey; Petersen, Ronald C.; Boeve, Bradley F.; Lucas, John A.; Reichard, Ross R.; Dickson, Dennis W; Knopman, David S.; Graff‐Radford, Neill R.; Murray, Melissa E
• Is Part Of: Alzheimer's & dementia. Volume 17(2021)Supplement 6
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-12-31
• Subjects: Alzheimer's disease -- Periodicals; Alzheimer Disease -- Periodicals; Dementia -- Periodicals; Démence; Maladie d'Alzheimer; Périodique électronique (Descripteur de forme); Ressource Internet (Descripteur de forme); 616.83
• DOI: 10.1002/alz.052376
• Languages: English
• ISSNs: 1552-5260

Abstract

Abstract: Background: Advancing age is an important risk factor for dementia and cancer. An inverse association between these conditions has been described, yet caution from potential biases/confounders is warranted. Dementia and cancer may represent a spectrum of opposing dysregulated degenerative (apoptosis) and growth (proliferative) pathways respectively (Driver, 2014). Risk or resiliency factors affecting these pathways may influence cognitive outcomes in the oldest‐old. We sought to investigate demographics, clinical characteristics, and the impact of medical comorbidity on possible risk‐resiliency factors for neurodegeneration in nondemented and demented oldest‐old who died and underwent autopsy. Method: Medical records of 161 decedents (female n=134) from the Mayo Clinic 95+ year‐old cohort (age range 95‐106 years‐old) were reviewed. Groups consisting of nondemented (n=72) and demented (n=89) decedents were stratified and compared according to demographics and clinical variables, including history of cancer. Autopsy and neuropathologic evaluation was also conducted. Result: Age at death, sex, race, and education showed no differences between nondemented and demented decedents. History of cancer was higher in nondemented (57%) compared to demented decedents (30%) (p=0.002). APOE ε4 allele presence did not differ amongst groups, while APOE ε2 allele was more common in the nondemented group (p=0.026). History of coronary artery disease was higher in the nondemented (p=0.033). No differences were observed in other vascular risk factors, alcohol use, or depression. Smoking history approached significance and was higher in nondemented compared to demented (p=0.068). MMSE scores were higher in the nondemented group (p<0.001). Neuropathology findings included a lower Braak tangle staging in nondemented (median=III) compared to demented (median=V) groups (p<0.001) and less frequent diffuse plaques observed in the nondemented (67%) compared with those demented (93%) (p<0.001). Conclusion: Dementia is less frequent among cancer survivors in the 95+ oldest‐old. Disease‐related mechanisms associated with malignancy and surviving it may be protective against neurodegeneration in the oldest old.