Alzheimer's Disease May Increase Risk of Anemia and Seizures
- Global Impact Could Multiply As The Population Continues to Age -
HONOLULU, July 13 /PRNewswire-USNewswire/ -- Having Alzheimer's
disease may increase the risk of getting other potentially
disabling health conditions, including seizures and anemia,
according to new research presented today at the Alzheimer's
Association International Conference on Alzheimer's Disease 2010
(AAICAD 2010) in Honolulu, HI.
"Alzheimer's disease is a global health crisis with devastating
effects on individuals, families, and national healthcare systems,"
said William Thies, PhD, Chief Medical and Scientific Officer at
the Alzheimer's Association. "If, in fact, Alzheimer's also
increases risk of other disabling conditions, then its impact may
be more devastating than we've envisioned as the global population
ages and as more countries become westernized in their habits and
lifestyles."
According to the 2009 World Alzheimer Report from Alzheimer's
Disease International, a London-based nonprofit, international
federation of 71 national Alzheimer organizations including the
Alzheimer's Association, the number of people with Alzheimer's or
another dementia, currently 35 million, is expected to nearly
double every 20 years, to 65.7 million in 2030 and 115.4 million in
2050.
Worldwide, the economic cost of dementia has been estimated as
$315 billion annually. (Wimo, et al. "An Estimate of the Total
Worldwide Societal Costs of Dementia in 2005." Alzheimer's &
Dementia: The Journal of the Alzheimer's Association. Vol. 3, Issue
2, April 2007.)
Alzheimer's is Associated with Increased Incidence of
Seizures
Some small studies have shown Alzheimer's to be a risk factor
for seizures. H. Michael Arrighi, PhD, of Janssen Alzheimer
Immunotherapy Research & Development; Nicole Baker, MPH,
Pfizer; and colleagues conducted an observational study to estimate
the incidence rate of seizures among a large cohort of people with
Alzheimer's. The researchers used anonymized electronic medical
records from nearly 400 primary medical practices in the United
Kingdom. The study population included 14,838 people with
Alzheimer's aged 50 years or older and a comparison cohort of
14,838 randomly-selected, age- and sex-matched patients without
Alzheimer's. People with Alzheimer's were followed for an average
of 2.3 years; non-Alzheimer's patients were followed for an average
of 3.4 years.
Over that time period, the researchers found that the rate of
seizures, per 1,000 people per year, was 9.1 among patients with
Alzheimer's disease compared with 1.4 for those without Alzheimer's
- an incidence rate that was 6.4 times higher. In addition, they
found that the incidence rate of seizures was highest among the
youngest Alzheimer's patients, and that it decreased with age.
Incidence among non-Alzheimer's patients increased slightly with
age.
"The increased risk of seizures among patients with Alzheimer's
disease was seen in all age groups, but there was a substantial
increase among the youngest patients. It is especially important
for these patients and their caregivers to be aware of this risk,"
Baker said.
"The connection between Alzheimer's and seizures provides
additional avenues for research into the basic biology of both
diseases, and possibly interventions and therapies to respond to
the overall impact of Alzheimer's disease" Arrighi said.
Alzheimer's is Associated with Lower Hemoglobin Levels and
Anemia
Studies suggest that iron accumulates in the tau tangles in the
brains of people with Alzheimer's, and that overall levels of iron
are elevated in both Alzheimer's and Mild Cognitive Impairment
(MCI) brains. However, it is not clear from the scientific
literature if this altered brain iron profile is reflected in
plasma iron levels.
Noel Faux, PhD, of the Mental Health Research Institute,
Parkville, Australia, and colleagues examined hemoglobin, iron and
other blood-based measurements in the 1,112 participants (768
healthy controls, 133 MCI, 211 Alzheimer's) of the Australian
Imaging Biomarkers and Lifestyle (AIBL) study of Ageing.
Participants also completed questionnaires on diet and medication
intake (including supplements). Results were then correlated with
measures of short-term, long-term and total memory, and global
cognition.
The researchers found that people with Alzheimer's in the study
had significantly lower levels of hemoglobin, mean cell hemoglobin
concentration (MCHC), and packed cell volume compared with healthy
controls, after adjustment for age and gender. Consistent with
these data, the erythrocyte sedimentation rate (ESR) was
significantly higher in Alzheimer's compared to healthy
controls.
Participants with anemia in the study were found to have an
increased risk of Alzheimer's (odds ratio: 2.56). And people with
Alzheimer's in the study were found to have an increased risk of
being anemic (odds ratio: 2.61). Self reported iron intake was not
different in the two groups.
"In our population, we found that people with Alzheimer's
disease were more likely to be anemic, and this was not explained
by dietary iron deficiency," Faux said. "This suggests that
hemoglobin production is deficient in Alzheimer's patients."
"Alzheimer's had not previously been recognized as a risk factor
for anemia, which is a common clinical problem for the elderly and
can contribute to problems such as heart failure and renal
failure," Faux continued. "The cause of anemia in Alzheimer's is
still uncertain, but we speculate that Alzheimer's is a disease
that affects both brain and blood. We are currently investigating
this intriguing possibility."
About AAICAD
The Alzheimer's Association International Conference on
Alzheimer's Disease (AAICAD) is the world's largest conference of
it's kind, bringing together researchers from around the world to
report and discuss groundbreaking research and information on the
cause, diagnosis, treatment and prevention of Alzheimer's disease
and related disorders. As a part of the Alzheimer's Association's
research program, AAICAD serves as a catalyst for generating new
knowledge about dementia and fostering a vital, collegial research
community.
About the Alzheimer's Association
The Alzheimer's Association is the leading voluntary health
organization in Alzheimer care, support and research. Our mission
is to eliminate Alzheimer's disease through the advancement of
research, to provide and enhance care and support for all affected,
and to reduce the risk of dementia through the promotion of brain
health. Our vision is a world without Alzheimer's. Visit
www.alz.org or call 800-272-3900.
EMBARGOED FOR RELEASE UNTIL TUESDAY, JULY 13, 2010, 11:30 am HST
/ 5:30 pm ET
-- Nicole L. Baker, H. Michael Arrighi, et al. Alzheimer's disease is
associated with increased incidence of seizures among patients in the
United Kingdom, 1988-2009. (Funded by: Janssen Alzheimer
Immunotherapy, Research & Development, LLC; Pfizer)
-- Noel G. Faux, et al. Alzheimer's disease is associated with lower
hemoglobin levels and anemia: The Australian Imaging Biomarker
Lifestyle (AIBL) study of ageing. (Funded by: Australian Commonwealth
Scientific Industrial and Research Organization, National Health and
Medical Research Council, The University of Melbourne, Neurosciences
Australia, Edith Cowan Universality, The Mental Heath Research
Institute, Alzheimer's Australia, National Ageing Research Institute,
Austin Health, University of Western Australia, Pfizer)
Source: Alzheimer's Association
CONTACT: Alzheimer's Association media line:
+1-312-335-4078,
media@alz.org, AAICAD 2010 press room,
July 10-15: +1-808-792-6523
Web Site: http://www.alz.org/
Posted: July 2010
