Many chronic disorders (eg, renal disease, cardiovascular disease, cancer) are associated with progressive weight loss.8-11 Affected patients may become cachexic, a state in which voluntary intake is poor and the body’s muscle proteins—rather than fat stores—are used to supply energy. The underlying disease process can increase metabolic rate, and weight loss can occur more rapidly than with simple starvation.
The impacts of unaddressed protein–energy malnutrition have been well established in human medicine, and intervention in affected humans may improve quality of life and longevity.12,13 Studies in companion animals with chronic kidney disease or heart failure have shown associations between BCS and longevity, and nutritional intervention may improve the well-being and outcome of these patients.8,9,11 If weight loss regardless of appetite is noted when a patient is diagnosed with a chronic disorder, an appetite stimulant should be included as part of the initial treatment plan. The stimulant can be adjusted or discontinued as appropriate and may prevent further decline in physical status.
In addition to the expected physiologic benefits of an improved energy balance, enhanced intake will likely reassure owners of their pet’s overall comfort and quality of life. Similarly, a consistent appetite supports compliance with complex medication plans; owners may become disheartened and frustrated by the effort needed to administer oral medications to a hyporexic pet. A full dietary history, including weight, BCS, and muscle condition score, should be obtained routinely in dogs and cats with chronic illness14 and an appetite stimulant prescribed as soon as concerns regarding intake are identified.