By Bruce Miller
Dementia is a collection of symptoms caused by a number of different disorders, including neurodegenerative diseases like Alzheimer’s disease and frontotemporal dementia. The term dementia describes a progressive decline in memory or other cognitive functions that interferes with the ability to perform your usual daily activities (driving, shopping, balancing a checkbook, working, communicating, etc.). One of the major risk factors for developing dementia is age, meaning the older you are, the more likely you are to develop it. Age-related risk applies to many other conditions like heart disease and vascular problems, which means a single person may have two or more concurrent health problems leading to cognitive, behavioral, or motor symptoms. This co-morbidity can make both diagnosis and treatment more complicated.
In the recent study by Michael Hurd of RAND, the estimated prevalence of dementia in people over age 70 in the US in 2010 was 14.7%. They calculated “that dementia leads to total annual societal costs of $41,000 to $56,000 per case, with a total cost of $159 billion to $215 billion nationwide in 2010.” Furthermore, the “aging of the US population will result in an increase of nearly 80% in total societal costs per adult by 2040.” This means an anticipated $73,800–100,800 per adult in 2040. In 2050, the oldest-old are projected to grow from 5.8 million in 2010 to 19 million, with people 85 and over accounting for 4.3% of the of the population (US Census Bureau). As there is no cure for dementia yet, these costs are largely driven by the costs involved in helping people live their daily lives—something that dementia makes progressively harder to do. “The main component of the costs attributable to dementia is the cost for institutional and home-based long-term care rather than the costs of medical services — the sum of the costs for nursing home care and formal and informal home care represent 75 to 84% of attributable costs” (Hurd et al. 2013).
How would a cure change this gloomy forecast? Without attempting to quantify any improvement in quality of life, a cure would have a major impact on these numbers. It is projected that a treatment that could merely delay the onset of symptoms for five years and “began to show its effects in 2015 would decrease the total number of Americans age 65 and older with Alzheimer’s disease from 5.6 million to 4 million by 2020” (Alzheimer’s Association). This delay would obviously have a huge impact on both the national economy and individual families. A prevention, cure, or reversal of symptoms would have an even larger impact.
There have been many clinical trials for potential Alzheimer’s treatments so far. Sadly, all have failed. Speculation on why these trials have failed has ranged from testing on patients that are too late in the disease to show any improvement to targeting the wrong molecular component of the disease. Scientists from public institutions and universities are currently collaborating through privately-funded consortia to investigate different targets (accumulated tau protein, accumulated beta-amyloid protein, or protein-clearing pathways) and patients with an earlier diagnosis (or even undiagnosed but carrying a gene that means they will develop the disease). If these groups can prove the principle behind a particular therapeutic in a small study, then a larger drug company might be able to take on the complexity and cost of adequate testing for safety and efficacy to develop a widely used therapy. While some of that investment will ultimately be passed back to the patient, the overall benefit should be profound at both the national and individual level.
For the first time, the health care providers for patients with dementia are hopeful and enthusiastic about the trials coming down the pipeline. The research is close; it just needs support to go the last mile.
Bruce L. Miller, MD is Professor of Neurology at the University of California, San Francisco (UCSF) where he holds the A.W. & Mary Margaret Clausen Distinguished Chair, teaches extensively and directs the busy UCSF dementia center. He is a behavioral neurologist focused in dementia with special interests in brain and behavior relationships as well as the genetic and molecular underpinnings of disease, and the author of Frontotemporal Dementia.
Image credit: Provided by the author. All rights reserved.