Thin body condition and weight loss are common in cats with chronic kidney disease (CKD). However, the time course and progression of weight loss before and after diagnosis have not been thoroughly evaluated. To describe weight loss in cats with CKD before and after diagnosis and its relationship to survival. A total of 569 cats (55.5% females and 44.5% males) with CKD from 6 US veterinary practices for which International Renal Interest Society (IRIS) stage, age, date of CKD diagnosis, and at least two body weight measurements were available. Body weight measurements were analyzed by time windows and polynomial growth curve analysis. Survival analysis was performed by Kaplan–Meier curves and log-rank tests. Median age at diagnosis was 14.9 years (range, 5.0–22.8 years). Cats were categorized at diagnosis as IRIS stage 1 (n = 34 [6%]), stage 2 (n = 345 [61%]), stage 3 (n = 141 [25%]), and stage 4 (n = 49 [9%]). Median body weight at diagnosis was 4.2 kg (range, 1.6–9.9 kg). Cats lost a median of 8.9% of body weight in the 12 months before diagnosis, but weight loss was already present 3 years before diagnosis and accelerated after diagnosis of CKD. Cats <4.2 kg at the time of diagnosis had significantly shorter survival time compared to cats ≥ 4.2 kg at diagnosis (P < .0001). Weight loss can be detected in cats before diagnosis of CKD, accelerates after diagnosis, and is associated with shorter survival. Tracking body weight may help clinicians in earlier diagnosis of CKD.

Objective—To evaluate clinically applicable methods of assessing lean body mass in dogs and compare muscle mass and inflammatory markers in healthy young and old dogs. Animals—9 healthy young (1 to 5 years old) and 10 old (> 8 years old) Labrador Retrievers with a body condition score of 5 to 6 of 9. Procedures—Radiography of the thoracolumbar region was performed for measurement of epaxial muscle height at the level of T13–L1. Computed tomographic images were obtained for the measurement of the epaxial and temporal muscles. Ultrasonography also was performed for regional muscle measurements at these same sites and the quadriceps muscle. Serum C-reactive protein, insulin-like growth factor-1, and tumor necrosis factor-α concentrations also were measured, and dogs' activity for 14 days was assessed with an activity monitor. Results—Mean epaxial muscle area measured by ultrasonography was significantly lower in the old group, compared with the young group, whereas epaxial muscle area measured by CT was only significantly lower in the old group after normalization for vertebral height. Neither temporal and quadriceps muscle measurements nor serum C-reactive protein or insulin-like growth factor-1 concentrations were significantly different between age groups. Tumor necrosis factor-α concentrations were undetectable in all dogs. Conclusions and Clinical Relevance—This study documented reduced epaxial muscle area in healthy old Labrador Retrievers, consistent with the syndrome of sarcopenia. Ultrasonography and CT were feasible methods of measuring epaxial muscle area, but much additional research is required to assess this method. A better understanding of underlying mechanisms of sarcopenia as well as methods for slowing progression is needed.

Feline Hypertrophic Cardiomyopathy: A Spontaneous Large Animal Model of Human HCM