Increasing age
The Burden of AD
Alzheimer’s disease (AD) is a progressive, neurodegenerative disease affecting about one in nine people in the US 65 years of aged and older.1,2 AD is responsible for 60% to 80% of dementia cases in people aged 65 and older.1 Additionally, AD is a leading cause of death among Americans, surpassing conditions such as diabetes, influenza, and pneumonia (Figure 1).3
This debilitating condition generally occurs in people over 65 years of age, with a prevalence rate of less than 10% before 65 years of age (Figure 2).1 After the age of 65, however, prevalence 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 among those aged greater than 85 years.1
So, what causes Alzheimer’s and dementia? It is believed that AD develops as a consequence of multiple risk factors (Figure 3). However, in rare cases (1% or less) the disease is related to the presence of certain genes/genetic mutations that can significantly increase risk. Apolipoprotein E (APOE) isoform e4, associated with sporadic/familial forms of AD that present after age 65, does not always result in the development of AD; however, carrying two ε4 alleles confers substantially higher risk (typically 10–15 times the general population risk, or up to 15-fold) than carrying one allele (typically 3-fold, or approximately 2–4 times).1 Notably, a mutation in the genes for presenilin (PSEN) 1 or 2 provides near certainty for AD development within a normal life span. These inherited mutations are autosomal dominant with near complete penetrance, and account for most familial early-onset AD (before age 65), though they represent only 5%–10% of all AD cases overall.1 Other risk factors for developing AD include1:
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,2,4 with caregivers (often family members) taking on the majority of care. In the US alone, nearly 12 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 at approximately $405,262 in 2024 dollars; caregivers often bear the bulk of this, with about 70% of costs due to unpaid caregiving and related out-of-pocket expenses ranging from medications to food for the person with dementia.2 Many caregivers work while providing care and report delaying or not participating in their own health maintenance.2 Costs associated with health care and long-term care of patients with AD or other dementias are expected to increase from $384 billion in 2025 to nearly $1 trillion in 2050 (in 2025 dollars).2
Detect Alzheimer’s understands what patients and caregivers face. We have compiled a list of patient and caregiver support networks here.
References
- Kumar A, Sidhu J, Lui F, Tsao JW. Alzheimer Disease. StatPearls. Last Update: February 12, 2024. https://www.ncbi.nlm.nih.gov/books/NBK499922/
- Alzheimer’s Association®. 2025 Alzheimer’s Disease Facts and Figures. https://www.alz.org/getmedia/ef8f48f9-ad36-48ea-87f9-b74034635c1e/alzheimers-facts-and-figures.pdf
- Centers for Disease Control and Prevention. (CDC). Leading Causes of Death. Last reviewed September 17, 2025. 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 Clin Neurosci. 2009;11:111-128. https://doi.org/10.31887/dcns.2009.11.2/cqiu
- Wolk DA, Dickerson BC. Clinical features and diagnosis of Alzheimer disease. UpToDate. Last update: September 30, 2024.https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-alzheimer-disease
All URLs accessed February 28, 2026
