Development of a Rat Clinical Frailty Index.
Rats are a commonly used model for aging studies, and a frailty assessment tool for rats would be of considerable value. There has been a recent focus on the development of preclinical models of frailty in mice. A mouse clinical frailty index (FI) was developed based on clinical frailty assessment tools. This FI measures the accumulation of clinically evident health-related deficits in mice. This paper aimed to develop a rat clinical FI. Male Fischer 344 rats were aged from 6 to 9 months (n = 12), and from 13 to 21 months (n = 41). A FI comprised of 27 health-related deficits was developed from a review of the literature and consultation with a veterinarian. Deficits were scored 0 if absent, 0.5 if mild, or 1 if severe. A FI score was determined for each rat every 3-4 months, and for the older group mortality was assessed up to 21 months. Mean FI scores significantly increased at each time point for the older rats. A high FI score measured at both 17 months of age and terminally was also associated with decreased probability of survival as assessed with Kaplan-Meier curves. The rat clinical FI has significant value for use in aging and interventional studies.
Physiology and Biophysics Department.
Amy
A
Yorke
Pharmacology Department, and.
Alice E
AE
Kane
Department of Surgery, Dalhousie University, Halifax, Nova Scotia, Canada.
Camille L
CL
Hancock Friesen
Pharmacology Department, and.
Susan E
SE
Howlett
Physiology and Biophysics Department.
Stacy
S
O'Blenes
D000368:Aged; D000375:Aging / Q000502:physiology*; D000818:Animals; D016330:Frail Elderly; D015577:Geriatric Assessment / Q000379:methods*; D006305:Health Status Indicators; D006801:Humans; D023421:Models, Animal; D009043:Motor Activity / Q000502:physiology; D010805:Physical Conditioning, Animal / Q000379:methods / Q000502:physiology / Q000592:standards; D051381:Rats; D012107:Research Design
Deficit accumulation; Frailty index; Preclinical models