Alzheimer's Patients May Have Symptoms of Depression Years Before Diagnosis
Dec. 9, 1999 (New York) -- Some key symptoms of depression such as lack of
interest, loss of energy, and poor concentration are increased in elderly
people in the years leading up to a diagnosis of Alzheimer's disease (AD),
according to a report in the Dec. 10 issue of the journal Neurology.
Unlike some previous reports suggesting that people who are depressed are more
likely to develop AD or that people with AD become depressed by their mental
deficits, the new study shows that the depressive symptoms are an early sign of
AD and could be important in obtaining the diagnosis.
"Treatment for Alzheimer's disease is becoming increasingly successful,
and the treatment is most likely to succeed if it's given early in the course
of the disease," study author Lars Backman, PhD, states in a press release
issued by the American Academy of Neurology. "Therefore, it is critically
important to diagnose Alzheimer's as early as possible. Looking for these
depression symptoms may be one way to identify who will develop Alzheimer's in
a few years."
Backman and colleagues from the Stockholm Gerontology Research Center in
Sweden examined 222 elderly individuals aged 74 years and older for presence of
depressive symptoms and dementia. After 3 years, 34 individuals had received a
diagnosis of AD.
Compared with nondemented individuals, those with AD were 50% more likely to
have depressive symptoms. Lack of interest, in particular, was three times more
common among people diagnosed with AD. There were no significant differences
between the groups in most mood-related symptoms such as unhappiness or
feelings of guilt, but those with AD tended to have more thoughts of death and
complained more about memory problems. The groups did not differ in rates of
another important depressive symptom, sleep disturbance.
An expert who reviewed the article for WebMD says the findings are
interesting and fit with similar work published earlier this year showing that
motivation-related depressive symptoms occurring prior to Alzheimer's are
likely the result of early changes in the structure of the brain. Doctors and
patients need to realize that there is a big difference between major
depression occurring in an elderly person and the emergence of depressive
symptoms that may be early signs of AD, says Eugene Rubin, MD, professor of
psychiatry at Washington University School of Medicine in St. Louis.