With the help of a non-invasive method of monitoring human activity, doctors and researchers at Columbia University Medical Center are shedding new light on a syndrome affecting nearly 40 percent of older adults with heart failure: anergia.
Anergia, or lack of energy, is a newly delineated, criterion-based geriatric syndrome that is often overlooked or dismissed by doctors and patients alike as simply a natural tiredness associated with "old age."
Whether anergia is a result of heart failure or perhaps a potential underlying contributing factor is not entirely clear. However, one thing is certain, researchers say: Fatigue has been shown to have independent long-term prognostic implications in patients with heart failure, suggesting that fatigue needs to be effectively evaluated not only because symptom alleviation is a target for treatment, but also because of the potential for the treatment of fatigue to influence the prognosis in patients with heart failure.
Mathew Maurer, M.D., associate professor of clinical medicine at Columbia University Medical Center, is the senior author of the study being published in the March 2009 edition of the Journal of Cardiac Failure.
As part of the nine-month prospective cohort study, heart failure patients were provided an actigraph - a device worn on the wrist like a watch that was used to assess physical activity, energy expenditures and sleep by measuring and recording limb movement.
Participants were instructed to wear it continuously on their non-dominant wrist for the nine months of the study. At baseline and at every three months for a total of four visits, each subject underwent a targeted physical exam including review of concomitant medications, co-morbid diagnoses, measurement of heart failure severity and distance walked during a six-minute hall walk as well as other mediating factors that might influence activity levels.
An earlier study by Dr. Maurer and the Stroud Center for the Studies of Quality of Life at Columbia University showed that anergia may stem from many conditions, including heart and kidney dysfunction, arthritis, lung disease, anemia and depression.
In the current study, Dr. Maurer, together with Susan Delisle, NP, and the Healthcare Innovation and Technology Lab at Columbia University, found significant discrepancies between self-reported fatigue and actigraphy readings, suggesting that these readings provide complimentary and important information about the link between heart failure, sleep disorders and impairments in health-related quality of life that may be operative through anergia.
Encouraged by the results, Maurer and his team have applied for a $2 million NIH grant to gather more data to further study the origins and challenges of treating anergia.
"The overall goal of our current research efforts is to develop methods to evaluate and assess the causal or contributing factors of anergia in order to develop interventions to decrease morbidity and mortality due to this syndrome," Dr. Maurer says.
Source: Columbia University Medical Center (news : web)
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