Clinical and laboratory findings and survival time associated with cardiac cachexia in dogs with congestive heart failure

Background: Cardiac cachexia, loss of muscle mass associated with congestive heart failure (CHF), is associated with increased morbidity and shorter survival times in people, but an association between cardiac cachexia and survival has not been reported in dogs.

Objectives: To determine the prevalence of cachexia and its associations with clinical, laboratory, and survival data in dogs with CHF.

Animals: Two hundred sixty-nine dogs with CHF.

Methods: Retrospective cohort study. Cachexia was defined by 1 of 2 definitions: (1) mild, moderate, or severe muscle loss or (2) weight loss of ≥5% in 12 months or less. Variables were compared between dogs with and without cachexia.

Results: One hundred thirty of 269 dogs (48.3%) had cardiac cachexia based on muscle loss, whereas 67 of 159 dogs (42.1%) with pre-evaluation body weights had cachexia based on weight loss. Dogs with cachexia (based on muscle loss) were significantly older (P = .05), more likely to have a cardiac arrhythmia (P = .02), had higher chloride concentrations (P = .04), and had a lower body condition score (P < .001), hematocrit (P = .006), hemoglobin (P = .006), and albumin (P = .004) concentrations. On multivariable analysis, cachexia (P = .05), clinically important tachyarrhythmias (P < .001), azotemia (P < .001), and being under- or overweight (both P = .003) were associated with shorter survival times.

Conclusions and clinical importance: Cardiac cachexia in common in dogs with CHF and is associated with significantly shorter survival. This emphasizes the importance of preventing, diagnosing, and treating muscle loss in dogs with CHF.