Is Dementia Preventable?
Science has long known about primary dementia, as a degenerative, progressive disease. Variants of primary dementia (now referred to as major neurocognitive disorder) include Alzheimer’s disease, vascular dementia, lewy-body disease, and fronto-temporal dementia, among others. But is dementia preventable? Until now, less attention has been paid to what are called secondary dementias, however. These are dementing conditions that are triggered by other, reversible factors, such as nutritional deficiency, traumatic stress, and even depression (sometimes referred to as pseudodementia, or false dementia).
Many of the clinical signs and symptoms are similar between the primary and secondary dementias. These include impaired reasoning, learning and memory, orientation, concentration, language, and executive functioning. But the distinguishing feature is that the secondary dementias, by definition, are reversible. My early work experience as a psychologist responsible for assessment in an inpatient geropsychiatric unit frequently turned up these cases of secondary dementia. And after proper medical treatment, good hygiene, healthy meals, and medication, these dementias often “cleared.”
New Spotlight on Modifiable Risks
Though research continues to seek to understand the causes and treatment of primary degenerative dementia, a new spotlight seems to be directed toward modifiable risks of dementia. “These are things we know how to change,” says Dr. Julio Rojas at the University of California at San Francisco. “If we can focus on behaviors and interventions that are widely available and for which there is strong evidence, we change our understanding of the ways dementia develops,” says Dr. Rojas.
A study was recently published in JAMA Neurology. It estimated that approximately 62% of dementia cases in the U.S. across all risk factors were possibly preventable. Vision impairment, one factor studied in this research, accounted for 1.8%, or 100,000 cases of preventable dementias. According to Dr. Joshua Ehrlich, ophthalmologist and lead author of the study, posits that this is a fixable, preventable condition through healthy vision practices. These include eye exams, eyeglass prescriptions, and cataract surgery. Eighty to 90% of vision impairment and blindness is avoidable through early detection and intervention.
For example, what are the connections between some of these risks like hearing and vision loss and cognitive decline? Neurologists explain that our neural system functions through stimulation from sensory organs. Without this stimulation, the neurons are inactive, and the brain gets reconfigured. Other risks for dementia exist due to a loss of “cognitive reserve.”
Scientists Identify 12 Risk Factors
In London in 2017, the Lancet Commission on Dementia Prevention, Intervention and Care identified nine risk factors accounting for much of the world’s dementia. The list includes high blood pressure, low education levels, impaired hearing, smoking, obesity, depression, physical inactivity, diabetes, and low levels of social contact. Three more were added in 2020: excessive alcohol consumption, traumatic brain injuries, and air pollution.
Key messages from the Commission’s report:
- Modifying these 12 risk factors may prevent or delay up to 40% of dementias
- Health practitioners should be ambitious about prevention
- It is never too early or too late to start mitigating dementia risk
Summary
In summary, the Lance Commission argues that focusing on these modifiable risk factors can offer reassurance for older adults. “These are things people can do in the communities where they live.”
An upcoming Living to 100 Club Podcast explores this very topic, with our guest, Dr. Paula Hartman-Stein. Paula will be discussing her chapter, Preventing What’s Preventable in Dementia. The chapter is included in a new text, Handbook of Evidence-based Prevention of Behavioral Disorders in Integrated Care. Look for this upcoming program.
Dr. Joe Casciani is the owner and Chief Curator for the Living to 100 Club, a source of solutions to living longer and healthier, with a special focus on mindset and attitudes about aging. He has a 40-year history as a psychologist and manager of mental health practices specializing in behavioral health services with older adults. In addition to his work as a clinical consultant, he is an engaging and inspiring speaker, and helps audiences move beyond their questions and concerns about aging to create a vision of what is possible in the years ahead. He strongly believes there is value in helping people feel inspired about their future.