You may or may not have heard rumblings about a hot topic in pet nutrition that was brought to light over the past few years. Diet-associated dilated cardiomyopathy (DCM) in dogs (but also in some cats) has caused quite a stir in veterinary medicine. In case you are unfamiliar with this phenomenon, we break down the basics below and provide an update on what is, and is not, yet known about this complex disease process. You are encouraged to pursue additional reading if you are interested using the links below from reputable sources or ask one of us at your next visit!
Dilated cardiomyopathy (DCM) is a disease of the heart muscle that makes the heart inefficient in pumping blood. This disease process can ultimately lead to congestive heart failure and death in certain cases. Signs of DCM can include lethargy, weakness, weight loss, cough, changes to breathing rate/effort, swollen belly, and sometimes even collapse or sudden death. In some cases of diet-associated DCM, the changes to the heart can improve once the pet’s diet is switched to a traditional diet and they are treated with medications, if warranted. In other cases, the changes are unfortunately irreversible or too far along to be responsive to interventions and the pet’s life may be cut short. Certain breeds of dogs are predisposed to a heritable form of this disease (such as Boxers, Great Danes, Doberman Pinschers, and Cocker Spaniels among others) but that is often considered a separate disease process.
When initial reports of diet-associated DCM were being reported, “BEG” diets were often involved. “BEG” diets include “boutique,” “exotic ingredient,” and “grain free” diets as a catch- all phrase. Given the correlation between grain free diets and this devastating heart disease in some pets, the recommendation had been to avoid grain free diets (and choose grain inclusive diets) until this correlation is better elucidated.
A lot of research has been done (and much is ongoing) to better understand these trends and we’ve made some progress, but we still have plenty of questions.
Some recent data has suggested a more common association between DCM and diets high in non-soy legumes, aka “pulses” (such as peas, lentils, chick peas, etc) and possibly potatoes/sweet potatoes. Although soy is considered a legume, it has not been implicated in an increased risk, unlike the above ingredients.
Since many grain-free diets had previously favored these alternative ingredients in place of grains, their incidence and association was likely automatically higher. Thus, the current trend for diet recommendations includes ensuring that pulses are not a large portion of the pet’s diet — whether grain free or not. Recommendations from the Petfoodology blog (written and maintained by board certified veterinary nutritionists at Tufts Cummings School of Veterinary Medicine) involve carefully considering diets with these ingredients listed in the top 10 on the back of the bag.
The FDA, veterinary researchers, and clinicians are still working hard to explore the exact connection between these diets and diet-related DCM, including what other factors may play a role in this devastating disease process (eg. genetics, concurrent medical conditions, etc). We’ll keep you posted as the veterinary community learns more!