The GERA-US study assessed societal costs associated with MCI and mild dementia, and caring for someone with Alzheimer disease, and was the first such study to show how the early stages of cognitive decline economically impact both patients and their caregivers.
Dorene M. Rentz, PsyD, professor of neurology, Harvard Medical School
Dorene M. Rentz, PsyD
Newly published results from the GERA-US study (NCT02951598) suggest that early Alzheimer disease poses a financial burden by which caregivers are significantly impacted, even among those with mild cognitive impairment (MCI) with higher rates of function. The major cost driver identified was patient clinical cognitive-functional status—not amyloid status—with differences mainly driven by an increasing need for caregiver support.1,2
The study assessed societal costs associated with MCI and mild dementia, and caring for someone with Alzheimer disease, and was the first such study to show how the early stages of cognitive decline economically impact both patients and their caregivers. It included 1327 patients, of which 679 had MCI and 650 had mild dementia.
"It is well known that caregiver costs increase with disease severity and this study demonstrates that those costs are incurred even earlier than we expected, at the stage of mild cognitive impairment. Clearly, memory loss in a loved one is not a benign event," coauthor Dorene M. Rentz, PsyD, professor of neurology, Harvard Medical School, said in a statement.2 "It has a detrimental impact on caregivers and families long before a diagnosis of AD dementia. This paper validates the importance of a timely diagnosis and reinforces the emerging science that treatment, even at the preclinical stage of disease, may benefit not only patients, but their caregivers as well."
Rentz and colleagues calculated cost with 2 methods: opportunity costs approach, which sums lost productive hours and multiplies them by national average annual gross hourly wage for workers and by lost leisure time for nonworkers; and replacement costs, which sums time associated with lost productivity and multiplies it by the market value of professional caregiver/aide hourly wage for all caregivers irrespective of working status of the study partner. They noted that in both methods, if a caregiver was paid for patient care, those hours were subtracted from the production loss time.
All told, those with mild dementia had higher total societal costs per month ($4243) compared with those with MCI ($2816; P <.001), which were not significantly different by amyloid status. Those with MCI who were amyloid positive (n = 300) had total (using opportunity costs) monthly costs of $2398 (replacement costs: $1745) while those who were amyloid negative (n = 283) had monthly costs of $3056 (replacement costs: $2218). Those with mild dementia who were amyloid positive (n = 317) and negative (n = 300) had monthly costs of $4001 (replacement costs: $2501) and $4337 (replacement costs: $2651), respectively.
These costs were not significantly different within each severity cohort by amyloid status. The largest fraction of overall costs were informal caregiver costs, accounting for 45.1%, for the mild dementia cohort, while direct medical patient costs were the largest for the MCI cohort, accounting for 39.0%. Caregiver time spent on basic activities of daily living (ADLs), instrumental ADLs, and supervision time was twice as high for those with mild dementia compared to MCI (P <.001 for all).
"It is important to recognize that Alzheimer disease represents a neurodegenerative continuum that shows, even in the earliest phase, cognitive deficits often lead to functional decline. This exacerbates the physical, emotional, and economic burden associated with progression into the early stages of dementia," co-author and US site investigator Ronald L. Schwartz, MD, said in a statement.2 "By using tools such as amyloid PET imaging, clinicians can improve diagnostic accuracy which allows for more focused management of both dementia as well as relevant co-morbidities which may influence neurocognitive changes associated with aging."
Those with mild dementia were also markedly more likely to fall below the 2016 federal poverty level (33%) compared to the MCI group (19%; P <.001), and less likely to report some college education (39.3% versus 63.8%, respectively; P <.001). Despite these differences, amyloid status did not result in differing measures for either severity cohort.
Additionally, those with mild dementia were less likely to work for pay (21.4%) versus those with MCI (9.4%; P <.001). They were also more likely to reduce their work hours due to Alzheimer disease (13.8% versus 3.2%, respectively; P = .007). A markedly higher percentage of amyloid-positive patients with mild dementia worked for pay (11.1%) compared to their amyloid-negative compatriots (7.7%; P  = .049).
"A timely and accurate diagnosis enables physicians to better manage their patients' medical comorbidities and assists caregivers' planning for present and future care needs," co-author Howard Fillit, MD, founding executive director and chief scientific officer, Alzheimer's Drug Discovery Foundation, said in a statement. "An early diagnosis also allows patients and loved ones to make choices about enrolling in a clinical trial as part of their plans."
1. Robinson RL, Rentz DM, Andrews JS, et al Costs of Early Stage Alzheimer’s Disease in the United States: Cross-Sectional Analysis of a Prospective Cohort Study (GERAS-US). J Alz Dis. 2020;75(2):437-450. doi: 10.3233/JAD-191212
2. Results of GERAS-US Study Demonstrate Societal Cost Burden for Patients and Caregivers During Early Stages of Alzheimer's Disease [press release]. Indianapolis, IN: Eli Lilly; Published May 19, 2020. Accessed June 4, 2020. biospace.com/article/releases/results-of-geras-us-study-demonstrate-societal-cost-burden-for-patients-and-caregivers-during-early-stages-of-alzheimer-s-disease