The Burden of AD

Alzheimer’s disease (AD) is a progressive, neurogenerative disease responsible for at least two-thirds of dementia cases in people age 65 and older, making it the most common cause of cognitive decline, affecting around 24 million adults worldwide.¹ About 1 in 9 persons in the US older than 65 years has Alzheimer’s dementia, with AD accounting for a leading cause of death among Americans, surpassing conditions such as diabetes, influenza and pneumonia.^2,3

This debilitating condition tends to affect those over 65, with less than 10% of cases occurring in younger people; before age 65, the incidence of AD is less than 1% per year.¹ After the age of 65, however, this number increases almost exponentially, doubling every 5 years.¹ Researchers are uncertain whether the incidence continues to climb with age or reaches a plateau.⁴ Some studies suggest that the incidence of AD in women may be slightly higher, especially with age greater than 85 years.¹

So, what is the cause of Alzheimer’s and dementia? It is believed that AD develops as a consequence due to multiple factors, with the exception of the presence of certain genes/genetic mutations which can significantly increase risk.² Apolipoprotein E (APOE) isoform e4, associated with sporadic/familial forms of AD, does not always result in the development of AD; however, higher risk is associated with two present alleles (90%) than with one allele (50%).¹ Notably, a mutation in the genes for presenilin (PSEN) 1 or 2 or the amyloid precursor protein (APP) provides a virtual certainty for AD development within a normal life span.^1,2 These inherited mutations are autosomal dominant with near complete penetrance, and account for 5%-10% of all AD cases as well as the majority of early-onset AD (before the age of 65).^1,2,5 It is believed that certain risk factors can be the causes of Alzheimer’s and dementia. Risk factors for developing AD include^1,2,5:

Increasing age

Traumatic brain injury (TBI)

Depression

Cardiovascular disease

Cerebrovascular disease

Increased homocysteine levels

Alzheimer’s disease places a heavy emotional and economic burden on families and society due to the need for ongoing therapy and support,⁴ with Alzheimer’s caregivers typically taking on the majority of care. In the US alone, about 11 million people provide unpaid care for their loved ones with AD or other forms of dementia.² Lifetime healthcare costs associated with dementia care are staggering, with individual estimates approaching $400,000 in 2021; caregivers bear a large burden of this, with 70% of cost due to unpaid caregiving and related out-of-pocket expenses such as food and medication.² Many caregivers work while providing care, and have reported delaying or not participating in their own health maintenance.2 Detect Alzheimer’s understands what patients and caregivers face. We have compiled a list of patient and Alzheimer’s caregiver support networks here.

References

Kumar A, Sidhu J, Goyal A, et al. Alzheimer Disease. StatPearls. 2022. https://www.ncbi.nlm.nih.gov/books/NBK499922/
Alzheimer’s Association^®. 2022 Alzheimer’s disease facts and figures: special report. More than normal aging: understanding mild cognitive impairment. Alzheimer’s Dement. 2022;18. https://www.alz.org/media/Documents/alzheimers-facts-and-figures.pdf
Centers for Disease Control and Prevention. (CDC). Leading Causes of Death. Last reviewed 9/6/22. https://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm
Qiu, C, Kivipelto, M, & von Strauss, E. Epidemiology of Alzheimer’s Disease: Occurrence, Determinants, and Strategies Toward Intervention. Dialogues in Clinical Neuroscience. 2009; 11:111-128.
Wolk, DA & Dickerson, BC. Clinical Features and Diagnosis of Alzheimer Disease. UpToDate. https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-alzheimer-disease