Dementia not only affects memory and quality of life, it can be fatal. A report released Thursday by the National Center for Health Statistics shows that the rate of Americans who died from dementia has more than doubled from 30.5 deaths per 100,000 people in 2000 to 66.7 in 2017.
The term dementia encompasses disease states that impair memory and result in a decline in cognitive function. These conditions seem to be affecting more of the population as it is expected to affect 14 million people age 65 and older by 2060, according to the US Centers for Disease Control and Prevention.
Dr. Ellen Kramarow, lead author of the new report and a health statistician for the Aging and Chronic Disease Statistics Branch for the National Center for Health Statistics, part of the CDC, explained that one cause of the rising number of deaths due to dementia in the United States is most likely because of the aging population. "If people live longer, they don't die of other causes, so they live to the point where the risk for dementia is higher," she said.
Researchers used data from death certificates from all 50 states and the District of Columbia. They examined four types of dementia recognized by the International Classification of Diseases: Alzheimer's disease, vascular dementia, unspecified dementia and other degenerative diseases of the nervous system. The authors adjusted for age which allowed them to compare people of different ages.
Alzheimer's disease accounted for 46% of the 261,914 deaths due to dementia in the United States in 2017. A finding which supports the need for ongoing research regarding Alzheimer's disease, Kramarow said.
Although the cause of Alzheimer's disease is not completely understood, researchers are gaining a better understanding of how it affects the brain. The disease destroys neurons, cells responsible for communication throughout the brain.
Dr. Chad Hales, assistant professor in the Emory University School of Medicine Department of Neurology, who was not involved in the report, explained that diagnosing dementia begins with a good clinical history and exam, brain imaging and lab studies to ensure that no other conditions are causing the symptoms.
Unfortunately, however, "the current gold standard is postmortem diagnosis with neuropathological confirmation," he said. Alzheimer's disease can be definitively diagnosed after a patient dies by looking at sections of the brain under a microscope which can reveal the presence of amyloid plaques and neurofibrillary tangles, structures in the brain unique to this disease.
As with any disease, the progression varies. "Alzheimer's disease causes degeneration of brain cells, and this leads to the outward symptoms you see on a day-to-day basis," Hales said. "This includes problems early on with short-term memory and later problems with speaking and executive dysfunction, like managing cell phones, medications, and finances. Patients can also have depression or other neuropsychiatric symptoms, like delusions or hallucinations."
As the disease progresses, symptoms usually become more apparent. According to the National Institute on Aging, it starts with parts of the brain responsible for memory, like the hippocampus, and works its way to the cerebral cortex, which is responsible for critical thinking and perceiving information. The symptoms of Alzheimer's disease typically appear in patients in their mid-60s and often first present as memory loss.
"Age is the greatest risk factor," Hales said, noting that as people age, they are more at risk of developing dementia.
The death rates associated with dementia more than doubled in 85- to 89-year-olds, compared with 90- to 94-year-olds, according to the report. Reflective of the population affected, 60.4% of deaths due to dementia in 2017 occurred in long-term care facilities, nursing homes or hospice facilities designed for end-of-life care.
The authors note that death certificate data alone is not completely comprehensive. "The only information we have is what is written on the death certificate. It's not connected to the person's medical record. They may have other conditions. There's no way to know from the death certificate alone," Kramarow said.
This report highlights that, although Alzheimer's disease contributes to many deaths in the United States, the other types of dementia should not be forgotten.
Regardless of the form, Hales said, "the most important thing to recognize is that you're not alone. There are so many people affected by this disorder, yet at times, patients and families feel isolated. We have to get past the stigma of this disease and recognize there there are others out there who may be able help or provide insight on the disease and symptoms that it causes."