Assessment and Management of Declining Physical Function in Aging Dogs

Aging is the leading cause of disability, disease, and death in adult dogs. One major consequence of aging is diminishing physical function. For normal functioning, basic elements such as strength, balance, and energy must be present. These must then be integrated to enable higher levels of function, from simple walking and feeding to the complex demands of social roles, such as family companion or working search-and-rescue dog. Biological aging processes, such as loss of muscle strength, diminished cardiorespiratory function, chronic inflammation, and age-associated diseases, as well as the adverse effects of medical treatments, all contribute to physical dysfunction. Contextual elements, such as lack of opportunity for physical exercise or restricted access to veterinary care due to owner socioeconomic circumstances, also influence age-associated functional decline in dogs. In humans, well-established clinical assessments are available to evaluate physical function, and these can predict disability, morbidity, and mortality. There are also well-supported interventions that preserve and restore function and reduce the risk of death and disease in the elderly. Because the fundamental biology and the clinical phenotype of aging are very similar in humans and dogs, these assessments and interventions can likely be adapted for use in mitigating declining physical function in geriatric canines. This review evaluates the decline in physical function with age in dogs and the potential utility in this species of clinical assessment tools and interventions developed for humans.