The Alzheimer's Disease Mortality Rate May Be Higher Than Officially Reported
Studies show that Alzheimer’s disease may be killing more than 500,000 people in the United States each year, which would make Alzheimer’s disease the third leading killer behind heart disease and cancer. More than 5 million people have a diagnosis of Alzheimer’s disease in the United States. That number is expected to triple by 2050 with the aging of the “Baby Boom” generation if there are no significant medical breakthroughs until then.
Under-reporting of Alzheimer’s as a cause of death on death certificates is not a surprise to many Alzheimer’s experts. Alzheimer’s disease is, in many cases, the disease that initiates a train of events that lead directly to death. However, death certificates often list an acute condition, such as pneumonia as the primary cause of death without including the Alzheimer’s disease diagnosis as the underlying or contributory cause of death. The Centers for Disease Control (CDC) data from 2013 reported that 84,767 people died with an Alzheimer’s disease diagnosis- based on death certificates, ranking it as the sixth leading cause of death and the fifth leading cause of death in people over the age of 65.
Death certificates require a single, primary cause of death, such as pneumonia. While there is room on the form to record underlying or contributory causes, several things may get in the way of accurate documentation. For example, the doctor who signs the death certificate may not know the person’s medical history or the person may not have been properly diagnosed even though it was evident that they had some form of dementia prior to the time of their death.
When a person dies, the cause or causes of death are listed on death certificates, by a physician, and filed with the state’s Bureau of Vital Statistics. This information is then forwarded to the National Center for Health Statistics of the Centers for Disease Control and Prevention (CDC), which compiles and reports the totals each year as the official U.S. mortality figures and leading causes of death. Other leading causes of death, such as cancer, heart disease, stroke and HIV have decreased since the year 2000, Alzheimer’s disease and related dementias have increased by an estimated seventy-one percent, according to the National Center for Health Statistics. According to Medicare data, approximately one-third of all seniors die with an Alzheimer’s disease diagnosis. Great strides have been made in research and treatment of cancer which gets about ten times as much funding as Alzheimer’s research does each year but is responsible for only three times as many deaths and a decline in the number of deaths each year.
In 2014, two groups of investigators at Rush University, Chicago, wanted to examine this phenomenon to gain a clearer picture of the full burden of Alzheimer’s disease now and in the decades to come. While their estimates of deaths due to Alzheimer’s in 2010 vary slightly, both groups determined that Alzheimer’s related mortality rates were several times higher than the official figures that had been reported.
In one study, the researchers combined data from the Chicago Health and Aging Project (CHAP) with U.S. census data to estimate the number of deaths of older Americans with Alzheimer’s 1. In a random sample of 1,913 CHAP participants age 65 and older, 990 people died over the course of 6 years. Data from this sample were used to calculate national Alzheimer’s mortality rates.
These findings, reported in the March 2014 issue of Alzheimer’s and Dementia, showed that an estimated 600,000 people age 65 and older with Alzheimer’s died in 2010. The researchers estimate that this number will rise to 900,000 in 2030 and to 1.6 million by 2050. This is an increase from 32 percent of deaths in people age 65 and older attributed to Alzheimer’s in 2010 to an estimated 43 percent in this population in 2050.
A study, published online on March 5, 2014, in Neurology, found that the number of deaths due to Alzheimer’s disease in people 75 and older could be six times higher than the official count 2. Researchers’ estimate of 503,400 deaths due to Alzheimer’s in 2010 among people in that age group would have made the disease the third leading cause of death in 2010, behind heart disease and cancer.
Researchers followed 2,566 participants in the ongoing Religious Orders Study and the Rush Memory and Aging Study 3 for 8 years. All participants, age 65 and older, were cognitively normal when they entered the studies. Over the course of the research, 22 percent of the volunteers developed an Alzheimer’s type dementia. About 72 percent of the people with Alzheimer’s disease died during that time frame, compared with 34 percent of those who remained symptom-free. Based on autopsy findings, the researchers concluded that death certificates do not reflect the large number of Alzheimer’s-related deaths 2.
Under-reporting the number of deaths due to Alzheimer’s disease isn’t a new problem and it isn’t just a statistical problem. By under-reporting the number of deaths due to Alzheimer’s disease and other forms of dementia, the burden of Alzheimer’s disease and other forms of dementia is understated, perpetuating the misconception that Alzheimer’s disease in not fatal.
Recording accurate numbers of deaths due to Alzheimer’s disease and other dementias is critical to demonstrate the true impact of these diseases and justify the need to increase funding for support programs and research.
Although there has been an increased effort to fund Alzheimer’s research and programs to benefit those impacted by Alzheimer’s disease and other dementias in the United States at the federal level with the passage of the National Alzheimer’s Project Act in 2011 and at the state level as many states have created a state plan; significantly increased funding is needed for research and programs to improve care, quality of life and reduce the emotional and financial burden of these diseases. As the Alzheimer’s mortality rate rises, so do our personal costs as well as the cost to our government. As a nation, we cannot afford to ignore or incorrectly report the statistics or under-fund Alzheimer’s disease and related dementias research and programs. References
1. Weuve J, et al. Deaths in the United States among persons with Alzheimer’s disease (2010–2050). Alzheimer’s & Dementia. 2014;10:e40-46.
2. James, Bryan, et al. Contribution of Alzheimer’s disease to mortality in the United States. Neurology. 2014 March; 82(12): 1045-50.
3. Religious Order Study conducted by the Rush University Medical Center, ongoing since 1993