Is Sarcopenia Reversible in Systolic Heart Failure?
Description: Sarcopenia is the age-related loss in fat-free body mass and deterioration in skeletal muscle function. Dual energy absorption X-ray (DXA) is the gold standard for sarcopenia diagnosis in the general population, with a standard diagnostic threshold of appendicular muscle mass index >2 standard deviations below the mean of a healthy young adult reference group. However, it is uncertain whether DXA is an appropriate method for sarcopenia assessment in patients with systolic heart failure (HF), due to abnormalities in extracellular water content in HF patients. HF patients are thought to be at additional risk of sarcopenia due to poor nutritional intake and physical activity, although the prevalence, pathophysiology and prognostic implications in this population are poorly defined. Many advanced HF patients who undergo implantation of a left ventricular assist device (LVAD) gain weight and experience improvement in the insulin resistant state of advanced HF. Changes in body composition, specifically fat-free mass (FFM), after LVAD implantation have not been published. This study seeks to determine the best method for body composition assessment in the advanced HF population and ascertain the degree of change in FFM during the months after LVAD implantation. We plan to recruit 40 subjects and determine body composition pre-LVAD, and 3 and 6 months post-LVAD implantation, using both DXA and stable isotope dilution techniques. Deuterium dilution will measurement of total body water and bromide dilution to measure extracellular water, which can be fluctuant in HF. We will evaluate whether DXA has sufficient agreement to the dilution technique in HF to implement DXA derived FFM as an endpoint in future studies, as well as to clinically target HF patients meeting sarcopenia criteria for additional management. We also plan to collect exploratory data about food intake, physical activity and resting energy expenditure, which may have mechanistic roles in FFM and body weight changes post-LVAD. The longer-term goal is to incorporate sarcopenia diagnosis and future nutritional therapies into the management of the wider HF population with an aim to improve quality of life and clinical outcomes.
Funder: American Heart Association
Amount: $230,000
Funding type: fellowship
Funder scheme: Scientist Development Grant
Start date: 2017-07-01
End date: 2020-06-30
Investigators: Amanda Vest, Amanda Vest
Institution: Tufts Medical Center
Funded outputs count: 2
Funder award ID: 17SDG33660279
OpenAlex ID: G6145504545