Evidence cluster — nutrition & cognitive dysfunction syndrome in cats (peer-reviewed, Europe PMC + PubMed)

Representative peer-reviewed studies (verbatim abstracts)

The following studies were retrieved from Europe PMC / PubMed and are reproduced verbatim. Interpretive synthesis is left to the API user.

PMID:36504872 — Age-related brain atrophy in cats without apparent neurological and behavioral signs using voxel-based morphometry.

Source: Front Vet Sci 2022
Front Vet Sci. 2022 Nov 24;9:1071002. doi: 10.3389/fvets.2022.1071002.

eCollection 2022.

Age-related brain atrophy in cats without apparent neurological and behavioral signs using voxel-based morphometry.

Hamamoto Y(1)(2)(3), Yu Y(2), Asada R(2), Mizuno S(2), Hasegawa D(2)(3).

Author information: (1)Veterinary Medical Teaching Hospital, Nippon Veterinary and Life Science University, Musashino, Japan. (2)Laboratory of Veterinary Radiology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Musashino, Japan. (3)The Research Center for Animal Life Science, Nippon Veterinary and Life Science University, Musashino, Japan.

INTRODUCTION: Brain atrophy is observed with aging and may cause cognitive decline or dysfunction. Aging cats may demonstrate behavioral changes related to cognitive dysfunction. In the clinical veterinary field, although the conventional region of interest method by manual or semiauto tracing on magnetic resonance imaging is used to detect atrophy of regional structures, such as the hippocampus, it is difficult to assess atrophy globally. Voxel-based morphometry (VBM) has been developed to detect global and regional abnormalities in humans. The purpose of the present study investigates whether the feline brain volume decreases with aging using VBM analysis. MATERIALS: A total of 65 cats, aged 17-200 months, without apparent neurological and behavioral signs were included in the statistical analysis. RESULTS: We observed that the gray matter in the bilateral parietal lobes was decreased significantly with aging. The regions that showed decreased volume included the right postcruciate, cingulate gyrus, rostral suprasylvian/ectosylvian gyri, and the left postcruciate gyrus. No significant reduction in white matter was observed. Together, our results show that age-related brain atrophy can be detected using VBM analysis. DISCUSSION: The age-related atrophy of the parietal cortex may not cause neurological and behavioral signs in cats. Therefore, veterinarians should consider age when assessing the relation between morphometric and functional abnormalities of the parietal cortex in cats.

DOI: 10.3389/fvets.2022.1071002 PMCID: PMC9729775 PMID: 36504872

Conflict of interest statement: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Abstract (verbatim excerpt):

JOURNAL:Front Vet Sci 2022

Front Vet Sci. 2022 Nov 24;9:1071002. doi: 10.3389/fvets.2022.1071002.

eCollection 2022.

Age-related brain atrophy in cats without apparent neurological and behavioral

PMID:40078212 — A non-randomized pilot study to test the feasibility of developing a frailty scale for pet cats.

Source: Front Vet Sci 2025
Front Vet Sci. 2025 Feb 26;12:1549566. doi: 10.3389/fvets.2025.1549566.

eCollection 2025.

A non-randomized pilot study to test the feasibility of developing a frailty scale for pet cats.

Colleran EJ(1), Delgado MM(2), Ren Y(3), German AJ(4), Gruen ME(5), Gunn-Moore DA(6), Romanowski K(7), Simpson W(8), Kirnos C(9), Keefe Ternes K(10), Karnia J(11), Temples M(12), Taylor SL(3), Bain M(13), Buffington CAT(13).

Author information: (1)Chico Hospital for Cats, Chico, CA, United States. (2)Feline Minds Cat Behavior Consulting, Sacramento, CA, United States. (3)Department of Public Health Sciences, School of Medicine, University of California, Davis, Davis, CA, United States. (4)Institute of Life Course and Medical Sciences, Faculty of Health and Life Sciences, University of Liverpool, Neston, United Kingdom. (5)Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, United States. (6)The Royal (Dick) School of Veterinary Studies and The Roslin Institute, The University of Edinburgh, Easter Bush Veterinary Campus, Edinburgh, United Kingdom. (7)Department of Surgery, School of Medicine, University of California, Davis, Sacramento, CA, United States. (8)Morrisville Cat Hospital, Morrisville, NC, United States. (9)The Cat Hospital of Media, Media, PA, United States. (10)The Feline Hospital, Salem, MA, United States. (11)Scottsdale Cat Clinic, Scottsdale, AZ, United States. (12)Civic Feline Clinic, Walnut Creek, CA, United States. (13)Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, Davis, CA, United States.

INTRODUCTION: Human frailty has long been studied and dozens of "frailty scales" have been developed, but equivalent research is more limited in cats. This pilot study aimed to determine the feasibility of recruiting and retaining veterinary practices and owners, collecting study data, and analyzing results about frailty in older cats. METHODS: Participating feline-exclusive practice veterinarians recruited cats aged 11-20 years, of either sex and of any breed. Owners completed a questionnaire about their cat and estimated its frailty. Study veterinarians also estimated the cat's frailty after obtaining a history, conducting a physical examination, and completing a separate questionnaire. The derived variables were used to investigate the following domains of frailty: (1) cognitive function; (2) behavior; (3) activity; (4) body weight; (5) body condition score; (6) muscle condition score; (7) any unexplained changes in weight, cognitive function, or eating behavior; and (8) the number of chronic diseases identified in the cat. Some cats were followed prospectively for 6 months, and mortality during this period was compared with frailty status, as determined by the veterinarian. RESULTS: Half (6/12) of the veterinary practices invited to participate successfully recruited 273 owner-cat pairs, with baseline questionnaire results obtained from 189 owners (69%) and veterinarian questionnaires obtained for 210 cats (77%). Of 122 cats having both owner and veterinarian questionnaire results, 45 (37%) were classified as frail by the owner and 51 (42%) by the veterinarian, with 28 (23%) classified as frail on both questionnaires. Of the cats with follow-up data, 13 of the 64 cats (20%) reported by veterinarians to be frail died or were euthanased during the 6-month follow-up, compared with only 1 of 54 cats (2%) that were not reported to be frail (Fisher's exact test P = 0.003). DISCUSSION: Developing a brief feline frailty questionnaire (FFQ) was feasible, and the results of such assessments were associated with 6-month mortality. A larger definitive trial should be considered to explore further the (dis)agreement between owners and veterinarians and better understand which frailty signs owners might be missing.

DOI: 10.3389/fvets.2025.1549566 PMCID: PMC11897749 PMID: 40078212

Conflict of interest statement: AG is an employee of the University of Liverpool, but his position is financially supported by Royal Canin and also received financial remuneration and gifts for providing educational material, speaking at conferences, and consultancy work, all unrelated to the current study. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision.

Abstract (verbatim excerpt):

JOURNAL:Front Vet Sci 2025

Front Vet Sci. 2025 Feb 26;12:1549566. doi: 10.3389/fvets.2025.1549566.

eCollection 2025.

A non-randomized pilot study to test the feasibility of developing a frailty

PMID:27370391 — What is healthy aging?

Source: J Feline Med Surg 2016
J Feline Med Surg. 2016 Jul;18(7):531. doi: 10.1177/1098612X16649522.

What is healthy aging?

Perea S, Scherk M.

DOI: 10.1177/1098612X16649522 PMCID: PMC10816675 PMID: 27370391 [Indexed for MEDLINE]

Abstract (verbatim excerpt):

JOURNAL:J Feline Med Surg 2016

J Feline Med Surg. 2016 Jul;18(7):531. doi: 10.1177/1098612X16649522.

What is healthy aging?

Perea S, Scherk M.

DOI: 10.1177/1098612X16649522 PMCID: PMC10816675 P

PMID:34167339 — 2021 AAFP Feline Senior Care Guidelines.

Source: J Feline Med Surg 2021
J Feline Med Surg. 2021 Jul;23(7):613-638. doi: 10.1177/1098612X211021538.

2021 AAFP Feline Senior Care Guidelines.

Ray M(1), Carney HC(2), Boynton B(3), Quimby J(4), Robertson S(5), St Denis K(6), Tuzio H(7), Wright B(8).

Author information: (1)The Cat Clinic of Roswell, Roswell, GA, USA. (2)WestVet Emergency and Specialty Center, Garden City, ID, USA. (3)College of Veterinary Medicine, Western University of Health Sciences, Pomona, CA, USA. (4)The Ohio State University, Department of Veterinary Clinical Sciences, Columbus, OH, USA. (5)Senior Medical Director, Lap of Love Veterinary Hospice, Lutz, FL, USA. (6)Brantford, ON, Canada. (7)Forest Hills Cat Hospital, Middle Village, NY, USA. (8)Mistralvet, Johnstown, CO, USA.

Erratum in J Feline Med Surg. 2021 Oct;23(10):NP4. doi: 10.1177/1098612X211040404.

Comment in J Feline Med Surg. 2021 Jul;23(7):611. doi: 10.1177/1098612X211021537.

The '2021 AAFP Feline Senior Care Guidelines' are authored by a Task Force of experts in feline clinical medicine and serve as an update and extension of those published in 2009. They emphasize the individual patient evaluation and the process of aging, with references to other feline practice guidelines for a more complete discussion of specific diseases. Focusing on each cat encourages and empowers the owner to become a part of the cat's care every step of the way. A comprehensive discussion during the physical examination and history taking allows for tailoring the approach to both the cat and the family involved in the care. Videos and analysis of serial historical measurements are brought into the assessment of each patient. These Guidelines introduce the emerging concept of frailty, with a description and methods of its incorporation into the senior cat assessment. Minimum database diagnostics are discussed, along with recommendations for additional investigative considerations. For example, blood pressure assessment is included as a minimum diagnostic procedure in both apparently healthy and ill cats. Cats age at a much faster rate than humans, so practical timelines for testing frequency are included and suggest an increased frequency of diagnostics with advancing age. The importance of nutrition, as well as senior cat nutritional needs and deficiencies, is considered. Pain is highlighted as its own syndrome, with an emphasis on consideration in every senior cat. The Task Force discusses anesthesia, along with strategies to allow aging cats to be safely anesthetized well into their senior years. The medical concept of quality of life is addressed with the latest information available in veterinary medicine. This includes end of life considerations like palliative and hospice care, as well as recommendations on the establishment of 'budgets of care', which greatly influence what can be done for the individual cat. Acknowledgement is given that each cat owner will be different in this regard; and establishing what is reasonable and practical for the individual owner is important. A discussion on euthanasia offers some recommendations to help the owner make a decision that reflects the best interests of the individual cat.

DOI: 10.1177/1098612X211021538 PMCID: PMC10812122 PMID: 34167339 [Indexed for MEDLINE]

Conflict of interest statement: Hazel Carney is a speaker for Royal Canin. Jessica Quimby is a key opinion leader for Boehringer Ingelheim Animal Health USA, Inc., Dechra, Elanco, Gallant Health Care, Heska, Hill’s Pet Nutrition, Inc., IDEXX Laboratories, Inc., Kindred Biosciences, Inc., Purina ProPlan Veterinary Diets, Royal Canin, and Zoetis Petcare. Sheilah Robertson acts variously as a key opinion leader, speaker and consultant for Elanco, Zoetis Petcare, and Jurox. The other members of the Task Force have no conflicts of interest to declare. [Image: see text]

Abstract (verbatim excerpt):

JOURNAL:J Feline Med Surg 2021

J Feline Med Surg. 2021 Jul;23(7):613-638. doi: 10.1177/1098612X211021538.

2021 AAFP Feline Senior Care Guidelines.

Ray M(1), Carney HC(2), Boynton B(3), Quimby J(

PMID:27370393 — Evaluating aging in cats: How to determine what is healthy and what is disease.

Source: J Feline Med Surg 2016
J Feline Med Surg. 2016 Jul;18(7):551-70. doi: 10.1177/1098612X16649525.

Evaluating aging in cats: How to determine what is healthy and what is disease.

Bellows J(1), Center S(2), Daristotle L(3), Estrada AH(4), Flickinger EA(5), Horwitz DF(6), Lascelles BD(7), Lepine A(8), Perea S(9), Scherk M(10), Shoveller AK(11).

Author information: (1)All Pets Dental, Weston, Florida, USA. (2)Cornell University, College of Veterinary Medicine, Department of Clinical Sciences, Ithaca, New York, USA. (3)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. (4)University of Florida, College of Veterinary Medicine, Department of Small Animal Clinical Sciences, Gainesville, FL, USA. (5)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. (6)Veterinary Behavior Consultations, St Louis, MO, USA. (7)North Carolina State University, College of Veterinary Medicine, Department of Clinical Sciences, Raleigh, NC, USA. (8)The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA. (9)The Iams Company, Mars Pet Care, 6574 State Route 503 North, Lewisburg, OH, USA Sally.Perea@royalcanin.com. (10)catsINK, Vancouver, BC, Canada. (11)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.

PRACTICAL RELEVANCE: Many of the changes that occur with aging are not considered pathologic and do not negatively affect overall wellness or quality of life. Ruling out disease is essential, however, when attempting to determine whether an aged cat can be considered 'healthy'. A clear understanding of the normal and abnormal changes that are associated with aging in cats can help practitioners make decisions regarding medical management, feeding interventions and additional testing procedures for their aged patients. CLINICAL CHALLENGES: It can be difficult to determine if a cat is displaying changes that are appropriate for age. For example, healthy aged cats may have hematologic or serum biochemistry changes that differ from those of the general feline population. Assessment of behavioral health and cognitive changes, as well as auditory, olfactory and visual changes, can also be challenging in the aged patient. GOALS: This is the second 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 second review proposes criteria for assessing 'healthy aged cats'. EVIDENCE BASE: There is a paucity of research in feline aging. The authors draw on expert opinion and available data in both the cat and other species.

DOI: 10.1177/1098612X16649525 PMCID: PMC10816674 PMID: 27370393 [Indexed for MEDLINE]

Conflict of interest statement: JB, SC, AHE, DFH, BDXL and MS all were paid for their contributions by Procter & Gamble Pet Care. LD, EAF, AL, SP and AKS have financial and personal interest in the Procter & Gamble Company; LD and EAF were employees of the company at the time of coauthoring this review. SP is an employee of Royal Canin, Mars Incorporated.

Abstract (verbatim excerpt):

JOURNAL:J Feline Med Surg 2016

J Feline Med Surg. 2016 Jul;18(7):551-70. doi: 10.1177/1098612X16649525.

Evaluating aging in cats: How to determine what is healthy and what is disease.

Bellows J(

PMID:27370392 — Aging in cats: Common physical and functional changes.

Source: J Feline Med Surg 2016
J Feline Med Surg. 2016 Jul;18(7):533-50. doi: 10.1177/1098612X16649523.

Aging in cats: Common physical and functional changes.

Bellows J(1), Center S(2), Daristotle L(3), Estrada AH(4), Flickinger EA(5), Horwitz DF(6), Lascelles BD(7), Lepine A(8), Perea S(9), Scherk M(10), Shoveller AK(11).

PRACTICAL RELEVANCE: 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. CLINICAL CHALLENGES: 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. GOALS: 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. EVIDENCE BASE: 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.

DOI: 10.1177/1098612X16649523 PMCID: PMC10816677 PMID: 27370392 [Indexed for MEDLINE]

Abstract (verbatim excerpt):

JOURNAL:J Feline Med Surg 2016

J Feline Med Surg. 2016 Jul;18(7):533-50. doi: 10.1177/1098612X16649523.

Aging in cats: Common physical and functional changes.

Bellows J(1), Center S(2), Daristot

Evidence cluster — nutrition & cognitive dysfunction syndrome in cats (peer-reviewed, Europe PMC + PubMed)

Representative peer-reviewed studies (verbatim abstracts)

PMID:36504872 — Age-related brain atrophy in cats without apparent neurological and behavioral signs using voxel-based morphometry.

PMID:40078212 — A non-randomized pilot study to test the feasibility of developing a frailty scale for pet cats.

PMID:27370391 — What is healthy aging?

PMID:34167339 — 2021 AAFP Feline Senior Care Guidelines.

PMID:27370393 — Evaluating aging in cats: How to determine what is healthy and what is disease.

PMID:27370392 — Aging in cats: Common physical and functional changes.

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