title: Aging in cats: Common physical and functional changes.
abstract: Aged pets comprise a significant proportion of the small animal veterinarian's patient population; in the USA, for example, it was estimated that over 20% of pet cats were 11 years of age or older in 2011. Certain changes associated with aging are neither positive nor negative, but others are less desirable, associated with illness, changes in mobility or the development of unwanted behaviors. These changes can greatly affect the health and wellbeing of the cat and have a tremendous impact on the owner.
  
  
  
  Regular veterinary examinations are essential for evaluating the health of older patients and for providing owners with guidance regarding optimal care. With the exception of overt disease, however, it is difficult to definitively determine if a cat is displaying changes that are appropriate for age or if they reflect an abnormal process or condition.
  
  
  
  This is the first of two review articles in a Special Issue devoted to feline healthy aging. The goals of the project culminating in these publications included developing a working definition for healthy aging in feline patients and identifying clinical methods that can be used to accurately classify healthy aged cats. This first review provides a thorough, systems-based overview of common health-related changes observed in cats as they age.
  
  
  
  There is a paucity of research in feline aging. The authors have drawn on expert opinion and available data in both the cat and other species.
authors.affiliation: All Pets Dental, Weston, Florida, USA.
authors.forename: Jan
authors.initials: J
authors.lastname: Bellows
authors.affiliation: Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, New York, USA.
authors.forename: Sharon
authors.initials: S
authors.lastname: Center
authors.affiliation: The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA L Daristotle's current address is: The Blue Buffalo Co, Wilton, CT, USA.
authors.forename: Leighann
authors.initials: L
authors.lastname: Daristotle
authors.affiliation: University of Florida, College of Veterinary Medicine, Department of Small Animal Clinical Sciences, Gainesville, FL, USA.
authors.forename: Amara H
authors.initials: AH
authors.lastname: Estrada
authors.affiliation: The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA EA Flickinger's current address is: Kent Pet Group, 2905 N Hwy 61, Muscatine, IA, USA.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Flickinger
authors.affiliation: Veterinary Behavior Consultations, St Louis, MO, USA.
authors.forename: Debra F
authors.initials: DF
authors.lastname: Horwitz
authors.affiliation: North Carolina State University, College of Veterinary Medicine, Department of Clinical Sciences, Raleigh, NC, USA.
authors.forename: B Duncan X
authors.initials: BD
authors.lastname: Lascelles
authors.affiliation: The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA.
authors.forename: Allan
authors.initials: A
authors.lastname: Lepine
authors.affiliation: The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA Sally.Perea@royalcanin.com.
authors.forename: Sally
authors.initials: S
authors.lastname: Perea
authors.affiliation: catsINK, Vancouver, BC, Canada.
authors.forename: Margie
authors.initials: M
authors.lastname: Scherk
authors.affiliation: The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA AK Shoveller's current address is: Department of Animal BioSciences, University of Guelph, ON, Canada.
authors.forename: Anna K
authors.initials: AK
authors.lastname: Shoveller
mesh_terms: D000375:Aging; D000818:Animals; D002415:Cats / Q000502:physiology*; D010808:Physical Examination / Q000662:veterinary