The absence of treatments to prevent or slow Alzheimer's coupled with a massive generation of aging baby boomers means there could be 7.7 million Alzheimer's patients age 65 and older by 2030. Unless effective interventions are introduced, rates of this disease as a cause of death are destined to increase.
Altzheimer's Basics
Alzheimer's is a progressive disorder in which brain cells degenerate and die. Its causes are unknown. According to the Alzheimer's Association, clinical symptoms include memory loss, language disorders and behavioral disturbances. Not everyone shows the same pattern of disorder, but Alzheimer's is a progressive and terminal illness.
Cause of Death Rankings
The CDC compiles annual rankings of the causes of deaths in the U.S. In its 2010 National Vital Statistics Reports examining the final 2007 data, Alzheimer's moved to sixth place surpassing diabetes. This CDC says this increase reflects a greater awareness of Alzheimer's patterns, changes in methods of reporting and increases in the actual number of deaths related to the aging population.
Death Rates
According to the Alzheimer's Association, people with Alzheimer's die an average of four to six years after diagnosis. A study of persons with dementia, 80 percent with Alzheimer's disease, reported in 2000, researchers found that after five years, 70 percent of those with dementia had died compared with 35 percent of those without dementia.
In addition, death rates among people with Alzheimer's increase significantly with age. A 2005 study published in the "Archives of Neurology" monitored nearly 1,700 people older than 15 years and found the mortality rate for persons with Alzheimer's age 75 to 84 was nearly 2.5 times greater than for those age 55 to 74.
The CDC reported a strong age-related death rate for Alzheimer's. In 2006, the death rate per 100,000 was 2.1 for persons 55 to 64, 20.2 for persons 65 to 74, 175.6 for persons 75 to 84 and 848.3 for persons older than 85.
Causes of Death
According to 2004 research published in the "Archives of Pathology and Laboratory Medicine," persons with Alzheimer's usually die from pneumonia, another respiratory illness or a cerebro-vascular condition. The pneumonia risk is tied to the loss of mobility and the extreme difficulty in swallowing common in late stage Alzheimer's. Cerebrovascular conditions are related to the significant deterioration of the brain tissue.
Reporting
The documentation of Alzheimer's deaths is problematic. The CDC's cause-of-death data follows the World Health Organization's regulations, which specify listing Alzheimer's on death certificates when it is the underlying cause. Researchers, however, have documented under-reporting of Alzheimer's. Studies of nursing home deaths reported in 1999 in the "Journal of Clinical Epidemiology," for example, show a significant under-reporting on death certificates even when individuals are in nursing homes due to Alzheimer's.
Other Illnesses
Persons with Alzheimer's often have co-occurring illnesses including heart disease, type 2 diabetes, cancer and stroke that may be contributing causes of death. In addition, it is common for persons with Alzheimer's to not have serious conditions diagnosed because of their Alzheimer's. This can blur the distinction between dying of Alzheimer's and having Alzheimer's but dying from another cause.
References
- CDC: National Vital Statistics Reports: May 2010.
- Alzheimer's Association: 2010 Alzheimer's Disease Facts and Figures.
- "Journal of Clinical Epidemiology": Dementia in Advanced Age Led to Higher Mortality Rates and Shortened Life: H. Agüero-Torres, L. Fratiglioni, Z. Guo, et al.. 1999.
- "Archives of Neurology": Altzheimer's Disease and Mortality, Mary Ganguli, MD; Hiroko H. Dodge, PhD; Changyu Shen, PhD; Rajesh S. Pandav; Steven T. DeKosky, MD: May 2005.
- "Archives of Pathology & Laboratory Medicine": Comorbidity in Dementia: Catherina Fu, Dennis J. Chute, Emad S. Farag, et al.: January 2004.
