Alzheimer's Disease Linked to Depression
May 19, 2003 -- Depression is a common early symptom of Alzheimer's disease, but it has been unclear whether a history of depression increases the likelihood of developing the degenerative brain disorder. Now new research offers some of the strongest evidence yet that it does.
Researchers found that people with a history of symptoms of depression were twice as likely to develop Alzheimer's disease. When the symptoms occurred within a year of the Alzheimer's diagnosis, there was a five-times stronger association between depression and Alzheimer's disease.
For families with a history of depression that occurred more than one year before the onset of Alzheimer's, the association was not as great but still significant. In families in which the symptoms of depression occurred more than 25 years before onset of Alzheimer's, the association was about 70% greater.
Lead investigator Robert C. Green, MD, MPH, tells WebMD the findings help to further clarify the risk factors associated with Alzheimer's, but are not meant to frighten people who have a history of depression.
"In terms of risk factors, this one appears to be pretty modest," the Boston University professor of neurology says. "But in the past five or six years we have been closing in on the factors that help define who is at lesser and greater risk for Alzheimer's, and this is another piece of the puzzle."
Other than age, emerging risk factors for Alzheimer's include family history and other genetic predispositions. Having high cholesterol, high blood pressure, and other risk factors for heart disease are also now believed to play a significant role in the development of Alzheimer's disease. Having a history of head trauma is also thought to be associated with increased risk, as is having low educational status.
"This is a very exciting time in Alzheimer's research because we are beginning to understand what is going on in people who get this disease," Alzheimer's Association director of medical and scientific affairs Jennie Ward Robinson, PhD, tells WebMD. "I am hopeful that within the next five to 10 years we will know the risk factors, and will have begun to identify treatments to prevent this disease and slow its progression."
Researchers found that people with a history of symptoms of depression were twice as likely to develop Alzheimer's disease. When the symptoms occurred within a year of the Alzheimer's diagnosis, there was a five-times stronger association between depression and Alzheimer's disease.
For families with a history of depression that occurred more than one year before the onset of Alzheimer's, the association was not as great but still significant. In families in which the symptoms of depression occurred more than 25 years before onset of Alzheimer's, the association was about 70% greater.
Lead investigator Robert C. Green, MD, MPH, tells WebMD the findings help to further clarify the risk factors associated with Alzheimer's, but are not meant to frighten people who have a history of depression.
"In terms of risk factors, this one appears to be pretty modest," the Boston University professor of neurology says. "But in the past five or six years we have been closing in on the factors that help define who is at lesser and greater risk for Alzheimer's, and this is another piece of the puzzle."
Other than age, emerging risk factors for Alzheimer's include family history and other genetic predispositions. Having high cholesterol, high blood pressure, and other risk factors for heart disease are also now believed to play a significant role in the development of Alzheimer's disease. Having a history of head trauma is also thought to be associated with increased risk, as is having low educational status.
"This is a very exciting time in Alzheimer's research because we are beginning to understand what is going on in people who get this disease," Alzheimer's Association director of medical and scientific affairs Jennie Ward Robinson, PhD, tells WebMD. "I am hopeful that within the next five to 10 years we will know the risk factors, and will have begun to identify treatments to prevent this disease and slow its progression."