Dementia: A Public Health Priority

This blog post is the first part of a two part series on dementia. Click here to read the next post.

Dementia is a growing and important public health issue. Dementia is a disease that causes a progressive decline in brain function. The communication system of the brain runs on neurotransmitters. There are more neurotransmitters in the human brain than there are stars in the entire galaxy.[ref]G.E. Healthcare, Untangling Alzheimer’s[/ref] Neurotransmissions become impeded by dementia, causing a decline in cognitive and, eventually, physical capabilities. To date, there is neither an effective treatment to stop the progression of dementia nor a cure for the disease. This blog post presents dementia statistics and explores diagnosis, societal and economic impacts, and methods to delay onset and slow progression.

The World Health Organization estimates that 47.5 million people worldwide have dementia. The growing senior population and increased life expectancy, combined with declining birthrates throughout the world, suggest that the global burden of dementia and associated care conundrum will be even more daunting in the future. Alzheimer’s Disease International projects that the number of new dementia cases is expected to nearly double every twenty years. The number of those with Alzheimer’s disease, the most common form of dementia, is estimated to be twenty seven to thirty six million.[ref]NIH Dementia: a public health priority, 2012[/ref]

Global Dementia Occurrence Chart-2
Infographic by Christina Manng.

Dementia occurrence rates vary from country to country, due in part to differences in diagnosing and reporting methods. Alzheimer’s Disease International estimates that between 2013 and 2050, the rates of dementia diagnosis are predicted to increase by ninety percent in Europe, 226 percent in Asia, 248 percent in America, and 345 percent in Africa. Countries with low and middle incomes account for an estimated fifty eight percent of all people with dementia; those numbers are projected to increase to sixty three percent in 2030 and sixty eight percent by 2050.[ref]Alzheimer’s Disease International[/ref] The fastest growing population of seniors is those eighty five and older. They are also the sickest segment of the elderly population.[ref]rand.org/labor/popmatters; Congressional Budget Office, 2013[/ref] Nations around the world do not have health systems that are able to sustain the rising need for caregivers, the mounting costs of treatment, and the long term care needs associated with dementia.

In the United States, dementia is a growing cause of both death and disability.[ref]Alzheimer’s Association, 2014 Alzheimer’s Disease Facts and Figures[/ref] In 2014, the US government recognized the expanding problem of dementia by granting forty five million dollars for innovative studies of Alzheimer’s disease, while increasing the funding allocation for Alzheimer’s research, education, outreach, and caregiver support by 122 million dollars.[ref]Alzheimer’s Association. Record $122 million increase for Alzheimer’s disease signed into law by President Obama.[/ref]

Dementia is not one disease. There are various types of dementia and many conditions that put an individual at risk for developing dementia. Alzheimer’s is considered the most common type of dementia. Other fairly common types are vascular dementia, frontotemporal dementia, and Lewy body dementia. It is not uncommon for Alzheimer’s and vascular dementia to coexist, nor is it unusual for people with different types of dementia to exhibit similar signs and symptoms. Alzheimer’s represents fifty to seventy percent of dementia cases, depending on the definitions used for inclusion. Knowing which type of dementia is present is necessary to identify the right medical treatment. For example, cognitive enhancer drugs do not work in all types of dementia. It is important to have an accurate diagnosis and not assume that a potential treatment for one type will work for another.

Diagnosis

Researchers need to find methods to screen for and diagnose the disease before symptoms occur. Like many diseases, by the time a dementia diagnosis is made, the disease has already advanced in the brain, causing cognitive decline and brain damage. Amyloid plaques and neurofibrillary tangles that occur in the brain can begin accumulating up to ten years before the symptoms of Alzheimer’s disease present themselves.[ref]G.E. Healthcare, Untangling Alzheimer’s[/ref]

Researchers contend that specific protein detection in cerebrospinal fluid and blood, genetic risk profiling, and brain imaging may eventually be able to predict the presence of Alzheimer’s in its early stages. One of the most recent advances in these studies is the discovery of a link between the protein TDP-43 and cognitive decline and Alzheimer’s. The research showed that those with the TDP-43 protein in their brains were ten times more prone to having cognitive impairment at death.[ref]McDonald, I. (2014). Day 4 AAIC2014 highlights: the latest research in dementia diagnosis, treatment, risk reduction and care. Alzheimer’s Australia Dementia Research Foundation.[/ref]

Today, detection occurs only after the disease has already caused damage. This delay in diagnosis greatly hampers the effectiveness of preventative interventions. The problem is further compounded by the current treatments available, which are aimed solely at the symptoms, and not the cause.

We are very much in need of new innovations for early detection, treatment, and prevention. Seventy five percent of those living with dementia in the United States are undiagnosed.[ref]Steenhuysen, J. (2011). Most cases of dementia are not diagnosed: report. Reuters.[/ref] According to the Organisation for Economic Co-operation and Development, fewer than half of those with dementia in England have been diagnosed.[ref]Department of Health, 2013[/ref] In Germany, that statistic is 44.5 percent.[ref]OECD, (2015), Addressing Dementia The OECD Response, OECD Health Policy Studies, OECD Publishing, Paris.[/ref]

Societal, Emotional, and Economic Impact

In 2015, the estimated global societal cost of all dementias was 818 billion dollars, a thirty four percent increase from 2010. This number is predicted to rise to two trillion US dollars by 2030.[ref]Alzheimer’s Disease International World Alzheimer’s Report 2015[/ref] Those costs include informal caregivers – unpaid caregivers that may include family, friends, neighbors, and volunteers – professional caregivers, and medical care. Although most people with dementia live in lower and middle income countries, nearly ninety percent of global dementia costs occur in high income countries.[ref]WHO Dementia: a public health priority, 2012[/ref] In the US, seventy five percent of those aged eighty and above with dementia live in a nursing home, compared to four percent of the general population in the same age group.[ref]Alzheimer’s Association, 2014 Alzheimer’s Disease Facts and Figures[/ref] Twenty five percent live with relatives or at home. It is projected that by 2040, dementia will represent twenty five percent of all Medicare spending in the US.[ref]Gillespie, L. (2015). Advocate for Alzheimer’s research says aging baby boomers face big threat from disease. Kaiser Health News.[/ref]

Studies show that people with dementia experience more hospitalizations and emergency department visits than those who do not have dementia.[ref]Feng, Z., Coots, L., Kaganova, Y., & Weiner, J. (2014). Hospital and ED use among Medicare beneficiaries with dementia varies by setting and proximity to death. Health Affairs;33(4):683-90[/ref] One study estimated that patients with dementia have six times more hospitalization days than those with asthma, hypertension, and diabetes combined.[ref]Integrated Model of Dementia Care. Champlain Dementia Network. Champlain 2020: Making Choices Matter[/ref] The cost of treating an episode for a dementia patient is significantly higher than the cost of treating an episode of other diseases.[ref]Ibid.[/ref] Patients with dementia incur a more expensive delivery of care and treatment, which can include treatment of often recurring coexisting illnesses.

The cost of housing those with dementia is a strain on families, elders, and governments around the world. Because of the unaffordable costs of skilled nursing care, many families have made the heartbreaking choice of sending their loved ones to be cared for abroad, in less expensive skilled nursing facilities.

Methods to Prevent or Delay Onset and Progression

Creative activities such as art, music, and dance can bypass the impairments of dementia. The film, “I Remember Better When I Paint” profiles programs from around the world that engage those who have dementia with art and music. The film portrays the power of connection that art can create in a person with dementia. Long after other memories have faded, long term memory of music remains. Aside from patients remembering lyrics and music, oftentimes, music can stimulate reactive emotions and memories. Researchers at the Max Planck Institute in Leipzig and the University of Amsterdam have discovered that the part of the brain that remembers music is less likely to lose motor neurons that other parts, when affected by Alzheimer’s.[ref]Long Term Musical Memory Spared Alzheimer’s Patients, (2015). Neuroscience News[/ref] These activities can reduce the risk or slow down the progression of dementia.[ref]Karkou, V. & Meekums, B. (2014). Dance movement therapy for dementia. Cochrane Database of Systematic Reviews, Issue 3, doi: 10.1002/14651858.CD011022[/ref][ref]Jayes, J. & Povey, S. (2011). The creative arts in dementia care: practical person-centered approaches and ideas. London: Jessica Kingsley.[/ref][ref]Vink, A.C., Birks, J., Bruinsma M.S. & Sholten R.J.P.M. (2011). Music therapy for people with dementia. Cochrane Database of Systematic Reviews, Issue 4, doi: 10.1002/14651858.CD003477.pub2[/ref] One longitudinal study linked participating in leisure activities, such as ballroom dancing, tennis, golf, reading, doing crossword puzzles, and playing musical instruments, to lower incidence of dementia. [ref]Verghese, J., Lipton, R., Katz, M., Hall, C., Derby, C., Kuslansky, G., Ambrose, A., Silwinski, M. & Buschke, H. (2003). Leisure activities and the risk of dementia in the elderly. The New England Journal of Medicine; 348:2508-2516[/ref] Creative activities do not involve costly medications or highly skilled care and can deliver improved quality of life, connection to community, and mental engagement and should be included in all care models.

Lack of social engagement has been linked to cognitive decline.[ref]National Institute of Health. Preventing Alzheimer’s disease: what do we know?[/ref] It is important to keep seniors connected to their communities to prevent loneliness and the associated cognitive decline. As the global senior population continues to grow, a focus on connection and contact should be a multi sectoral priority and include families, neighborhoods, cities, and state programs, along with local, state, and federal policy.

Lifestyle can affect one’s chances of developing dementia. Social determinants are often a factor. Dementia is linked with vascular issues caused by specific lifestyle choices. Smoking is associated with a higher risk of dementia.[ref]Rusanen, M., Kivipelto, M., Quesenberry, C.P., Zhou, J. & Whitmer, R.A. (2011). Heavy smoking in midlife and long-term risk of Alzheimer disease and vascular dementia. Archives of Internal Medicine Journal, 171(4): 333-339.[/ref][ref]Alzheimer’s Association 2015 Alzheimer’s Disease Facts and Figures.[/ref] Other lifestyle related dementia risk factors include midlife hypertension[ref]Duron, E. & Hanon O. (2008). Vascular risk factors, cognitive decline, and dementia. Vascular Health and Risk Management, 4(2):241-260.[/ref][ref]Kenelly, S.., Lawlor B.A. & Kenny R.A. (2009). Blood pressure and dementia-a comprehensive review. Therapeutic Advances in Neurological Disorders 2(4):241-260.[/ref][ref]Paganini-Hill, A. (2012). Hypertension and dementia in the elderly: The Leisure World cohort study. International Journal of Hypertension, doi 10.1155[/ref] and midlife high cholesterol.[ref]Meng, X.F., Yu, J.T., Wang H.F., Tan, M.S., Wang, C., Tan, C.C. & Tan, L. (2014). Midlife vascular risk factors and the risk of Alzheimer’s disease: A systematic review and beta-analysis. Journal of Alzheimer’s Disease 42(4):1295-1310.[/ref] As the years of formal education increase, the risk for Alzheimer’s disease declines.[ref]Stern, Y. (2012). Cognitive reserve in ageing and Alzheimer’s disease. The Lancet Neurology 11(11):1006-1012.[/ref][ref]Alzheimer’s Association. Stay Mentally Active.[/ref] Some researchers assert that education increases the connections within the brain. These additional connections are referred to as “cognitive reserve.”[ref]Stern, Y. (2012). Cognitive reserve in ageing and Alzheimer’s disease. The Lancet Neurology 11(11):1006-1012.[/ref]

In 1958, the National Institute on Aging began conducting the longest running study of human aging in the US, the Baltimore Longitudinal Study on Aging, led by Dr. Madhav Thambisety. The study was conducted over a period of fourteen years with 1,394 participants. The study looked at the relationship of obesity or excess weight in midlife to earlier onset of Alzheimer’s disease. The study found that each unit of increase in body mass index (BMI) at age fifty accelerated the onset of Alzheimer’s disease by almost seven months for those who developed the disease. The study also found that a higher midlife BMI led to a higher level of neurofibrillary tangles and amyloid proteins in the brain for participants who both did and did not develop Alzheimer’s disease.[ref]Chuang, Y.F., An, Y., Bilgel, M. Wong, D.F., Troncoso, J.C., O’Brien, R.J., Breitner, J.C., Ferruci, L., Resnick, S.M., & Thanbisetty, M. (2015). Midlife adiposity predicts earlier onset of Alzheimer’s dementia, neuropathology and presymptomatic cerebral amyloid accumulation. Molecular Psychiatry. Doi: 10.1038/p. 129.[/ref]

Type 1 and Type 2 diabetes mellitus also increase the likelihood of developing dementia. Almost half of the US population has pre diabetes or diabetes.[ref]Glatter, R. (2015). Half of adults in the U.S. have diabetes or pre-diabetes, study finds. Forbes/Pharma & Healthcare.[/ref] Rachel Whitmer, a senior scientist at Kaiser Permanente in Oakland, California conducted a study of the link between diabetes and the development of dementia in seniors. The study found that those with type 1 and type 2 diabetes had an eighty three percent greater likelihood of developing dementia. [ref]Gordon, S. (2015). Type 1 diabetes linked to higher risk of dementia. U.S. News and World Report Health.[/ref] This study supports a link but does not conclude that diabetes is a direct cause of dementia. Type 1 diabetes is not a preventable disease.

Those with type 2 diabetes have almost twice the risk for dementia.[ref]Anderlson, P. (2015). Type 2 diabetes linked to Tau tangles in brain. Medscape Medical News/Neurology.[/ref] Higher levels of the tau protein are found in the cerebral spinal fluid of people with type 2 diabetes, and elevated levels of this protein contribute to the buildup of neurofibrillary tangles.[ref]Ibid.[/ref] According to the World Health Organization, in 2014, the global prevalence of diabetes was nine percent. Ninety percent of those cases are type 2, which is preventable. The cost of treating diabetes and related chronic diseases, including dementia, is overwhelming health systems around the world.

One study found that nearly one third of global Alzheimer’s cases might be caused by modifiable risk factors, including access to education and healthier lifestyles.[ref]Norton, S., Matthews, F., Barnes, D., Yaffee, K. & Brayne, C. (2014). Potential; for primary prevention of Alzheimer’s disease: an analysis of population-based data. The Lancet Neurology, 13(8), 788-794.[/ref] Cardiovascular exercise has shown to be one of the most effective deterrents to the disease.[ref]Ahlskog, J., Geda, Y., Graff-Radford, N. & Peterson, R. (2011). Physical exercise as a preventive or disease-modifying treatment of dementia and brain aging. Mayo Clinic Porceedings, 86(9): 876-884.[/ref] Studies have also shown that cardiovascular exercise improves the cognitive function of those who already have dementia.[ref]Ibid.[/ref]

Initiatives that incentivize health and wellness are quickly becoming standard practice for health insurers, public and private enterprises, and employers. Exercise has proven to reduce the risk of dementia in those age sixty five and older[ref]Larson, E.B., Wang, L., Bowen, J.D., McCormic, W.C., Teri, L., Crane, P. & Kukull, W., (2006) Exercise is associated with reduced risk for incident dementia among persons 65 years of age and older. Annals of Internal Medicine, Vol 144, No. 2.[/ref] and decrease the likeliness of high cholesterol and hypertension. Programs that increase access to education, build healthy communities, deter smoking and consumption of sugary beverages offer an opportunity to improve the quality of population health and prevent or delay the onset of dementia.

Now that I have discussed some of the challenges posed by dementia, stay tuned for part two of this blog series, which will look at promising clinical and policy solutions to meet these challenges.