In people aged >85 years, anemia was associated with increased risk for death independent of comorbidity.
Prevalent anemia in people aged older than 85 years and
incident anemia in the subsequent years were associated with an elevated risk
for death, even after adjustment for comorbid conditions, according to the
results of a study published in the Canadian Medical Association
Wendy P.J. den Elzen, MSc, and colleagues from
University Medical Center, in the Netherlands, analyzed data from 562
participants from the Leiden 85-plus Study, a population-based, prospective,
follow-up study of inhabitants of Leiden aged 85 years. Participants were
followed for five years.
Associations between anemia and mortality and functional
status, including disability in basic and instrumental activities of daily
living, cognitive function and the presence of depressive symptoms, were
Anemia was defined according to World Health
Organization criteria: hemoglobin level <120 g/L for women and <130 g/L
At baseline, the prevalence of anemia was 26.7%.
Participants with anemia had a higher risk for death than those without anemia
(HR=1.71; 95% CI, 1.40-2.10). After adjustment for variables, including
comorbid illnesses, those with anemia remained at higher risk (HR=1.41; 95% CI,
Additionally, a dose-response relationship was observed
between severity of anemia and mortality risk when participants were divided by
mild, moderate or severe anemia, according to researchers.
There was no difference in functional decline between
those with and without anemia; however, in adjusted analysis, anemia was linked
to increased disability in basic activities, and instrumental activities of
During the follow-up period, incident anemia developed
in 24.0% of participants who did not have anemia at baseline. In unadjusted
(HR=2.16; 95% CI, 1.68-2.77) and adjusted analysis (HR=2.08; 95% CI,
1.60-2.70), participants who developed anemia had a twofold risk for mortality
compared with those who did not develop anemia.
Incident anemia was associated with increased disability
in basic activities of daily living (P<.01). In adjusted analysis,
incident anemia remained a risk factor for increased disability in basic
activities of daily living.
“For unexplained anemia in elderly patients, we may
never be able to disentangle whether the underlying cause or the anemia is
responsible for death,” Ora Paltiel, MSc, and A. Mark Clarfield,
MD, wrote in an accompanying editorial.
Paltiel is an associate professor in the department of
hematology and school of public health at Hadassah-Hebrew University,
Jerusalem. Clarfield is a professor, faculty of health sciences at
Ben-Gurion-University of the Negev, Israel.
“In their study, den Elzen and colleagues corrected
for as many factors as possible, but the risk for residual confounding by
underlying disease remains,” they wrote.
To determine the true and independent effect of the
treatment of anemia on mortality and functional decline in the elderly
population, randomized, controlled trials are necessary, according to the
Elzen PJ. CMAJ. 2009;doi:10.1503/cmaj.090040.
Paltiel O. CMAJ. 2009;doi:10.1503/cmaj.091199.