Cause of increased canine, feline DCM incidence remains a mystery

The following story by Phyllis Entis first appeared in Food Safety News and is reposted here with permission.

Between Jan. 1, 2014, and Nov. 30, 2018, the Food and Drug Administration received reports of 325 cases of dilated cardiomyopathy (DCM) involving dogs, and 10 involving cats, according to an investigation update released Feb. 19. Two of the cats died, as did 74 of the dogs.

In some cases, more than one pet in a household was affected. 

In July 2018, FDA announced that it had begun investigating reports of DCM in pets who were fed certain pet foods containing high proportions of peas, lentils, pulses and/or potatoes. Many of the implicated pet foods are advertised as “grain-free.” Most of the reports, 276 out of 300, were received following the FDA’s announcement.

The investigation update does not include data from December 2018 or January 2019, as the partial government shutdown prevented FDA from continuing its investigation during that time period.

DCM is a recognized genetic condition in some dog breeds, including doberman pinschers, great danes, and Irish wolfhounds. It also has been reported in cocker spaniels.

Animals suffering from DCM develop an enlarged heart and may display symptoms such as decreased energy, cough, difficulty breathing and episodes of collapse. If caught early, the condition can be partially reversed with appropriate treatment and diet modifications.

The current spate of DCM reports is not limited to dog breeds known to have a genetic predisposition to the disease, but includes the following breeds, in descending order by frequency of reports: golden retrievers, mixed breed dogs, Labrador retrievers, great danes, Australian shepherds, German shepherds, pit bulls, boxers, doberman pinschers, mastiffs, American cocker spaniels, standard poodles, Shetland sheepdogs, weimaraners, French bulldogs, Australian cattle dogs, Boston terriers, bulldogs, samoyeds, and shih-tsus.

Other breeds with more than one case report include: Afghan hound, beagle, dalmatian, English springer spaniel, flat-coated retriever, unspecified hounds, Maltese, miniature schnauzer, pomeranian, Portuguese water dog, pug, unspecified retriever, Rhodesian ridgeback, rottweiler, saluki, vizsla, and Yorkshire terrier.

Ages of affected dogs range between less than 6 months to 16 years. Dogs suffering from DCM weighed between 8 pounds and 212 pounds. More male dogs than female dogs have been affected.

In contrast, genetically related DCM tends to involve middle-aged to older aged male dogs of large and giant breeds.

The majority of cases reported to FDA, 269 of 325, involved dogs fed dry foods, approximately 90 percent of which were reported to be “grain-free.” Although most of the diets included an animal protein, such as fish, eggs, lamb or chicken, no single source predominated.

Since beginning its investigation, FDA’s Veterinary Laboratory Investigation and Response Network (Vet-LIRN), has tested various products for minerals and metals including calcium, magnesium, phosphorus, iron, cobalt, copper, zinc, selenium and iodine. They also tested for amino acids, including taurine, cysteine and methionine. Cysteine and methionine are required for the body to manufacture taurine.

In addition, Vet-LIRN has tested both grain-free and grain-containing products for protein, fat, moisture, crude fiber, total dietary fiber, soluble fiber, insoluble fiber, total starch, and resistant starch. Grain-free products were higher in fiber and lower in starch than grain-containing products. Otherwise, there was very little difference between the grain-free and grain-containing products.

FDA has received lab reports, diagnostic records such as echocardiograms, and necropsy reports from some of the affected dogs. In addition, the agency is collaborating with Chesapeake Veterinary Cardiology Associates (CVCA) on a prospective study of DCM-diagnosed dogs. 

CVCA is collecting medical records, owner interviews, diagnostic samples from each of the diagnosed animals, and is archiving feces and DNA samples for possible future testing.

FDA also has been working with Drs. Lisa Freeman of Tufts University, Joshua Stern of the University of California-Davis, and Darcy Adin of the University of Florida. Stern has been studying the increases in DCM cases in golden retrievers. Many of these cases are associated with taurine deficiency.

The FDA reported it is not aware of similar DCM illness reports or investigations in other countries, according to a spokesperson for the agency, adding that FDA would welcome the opportunity to collaborate with international counterparts on diet-related DCM. 

A number of researchers in Canada and the United States, led by W.D. Mansilla of the University of Guelph in Ontario, Canada, recently issued a report on the association between DCM and pulse ingredients in pet food. They suggested L-carnitine deficiency as another possible avenue of investigation into the cause of non-hereditary DCM.

L-carnitine, an amino acid, occurs naturally in animal protein, but is absent from plant protein. It is present at highest concentration in red meats such as lamb and beef, and at a lower level in pork, poultry and fish.

When asked whether FDA was examining the possible effect of L-carnitine on the development of DCM, an agency spokesperson said the agency and its investigative partners “. . . are considering or open to considering any science and evidence-backed theory.”

Guidance to pet owners and veterinarians
If a dog is showing possible signs of DCM or other heart conditions, including decreased energy, cough, difficulty breathing and episodes of collapse, contact your veterinarian as soon as possible. If the symptoms are severe and your veterinarian is not available, you may need to seek emergency veterinary care. Be prepared to provide your veterinarian with a thorough dietary history, including all the foods (including treats) the dog has eaten.

The FDA encourages veterinary professionals to report well-documented cases of DCM in dogs suspected of having a link to diet by using the electronic Safety Reporting Portal or calling their state’s FDA Consumer Complaint Coordinators.

The more information veterinarians provide, particularly feeding history, medical records, and diagnostic testing, the better. Detailed instructions can be found on “How to Report a Pet Food Complaint.” Technical veterinary information that may aid veterinarians can be found in the agency’s Vet-LIRN Update – February 2019.


FDA continues to review possible link between pet diets and canine heart disease

This story by Phyllis Entis first appeared in Food Safety News and is reposted here with permission

A diet rich in legumes or potatoes might be linked to an increased risk of canine dilated cardiomyopathy (DCM), according to the Food and Drug Administration.

Prior to issuing a public notice on July 12, the FDA had received sporadic reports involving 30 dogs and 7 cats over a three-year period. During that same period, the veterinary cardiology community received about 150 similar reports. In dogs, the disease results in an enlarged heart.

Some of the dogs exhibited signs of heart disease, including decreased energy, cough, difficulty breathing, and episodes of collapse. Reports received by FDA identified a range of brands and formulas. 

The common element in these foods appears to be the presence of legumes (including peas, beans, lentils, chickpeas, soybeans, peanuts), pulses (seeds of legumes), and/or potatoes as main ingredients in the pet foods. The list also encompasses protein, starch or fiber derived from legumes.

Since the July 12 notification, FDA has received additional reports, which it is in the process of evaluating. None of these reports involve cats. According to a spokesperson from FDA, the agency is not able to provide an accurate accounting at this time, as the number of reports is continuing to rise and the information is being analyzed as it is received.

Some dog breeds are genetically susceptible to developing DCM. However, at least some of the initial reports to FDA involved other breeds of dog not typically prone to this disease. FDA is evaluating various possible dietary causes of DCM in dogs, including, nutritional makeup of the main ingredients or how dogs process them, main ingredient sourcing, processing, and amount used.

At this point in its investigation, FDA is not advising dog owners to make any dietary changes. Pet owners whose dogs are showing any symptoms of DCM or other heart conditions should contact their veterinarian.

FDA is encouraging pet owners and veterinary professionals to report cases of DCM in dogs suspected of having a link to diet by using the electronic Safety Reporting Portal or calling their state’s FDA Consumer Complaint Coordinators.

FDA warns of possible link between food, canine heart disease

This article by Phyllis Entis first appeared in Food Safety News and is reposted here with permission. 

Pet foods containing peas, lentils, other legume seeds or potatoes as main ingredients may be linked to cases of canine dilated cardiomyopathy (DCM) in dogs, according to an alert to pet owners this week from the Food and Drug Administration.

Certain large and giant breed dogs, including great danes, boxers, Newfoundlands, Irish wolfhounds, saint bernards and doberman pinschers, are thought to have a genetic predisposition to DCM. Atypically, cases of DCM reported to FDA have been of mixed breeds and of smaller breeds that were not thought to be predisposed to this condition, including: golden and Labrador retrievers, whippets, a Shih Tzu, a bulldog and miniature schnauzers.

Canine DCM is a disease of the heart muscle, resulting in an enlarged heart, which can lead to congestive heart failure if not treated successfully. Dogs suffering from DCM may show symptoms of heart disease, such as decreased energy, cough, difficulty breathing and episodes of collapse.

In June 2017, Dr. Joshua Stern,  associate professor of cardiology in the School of Veterinary Medicine at the University of California-Davis, alerted the veterinary community to reports of  DCM in golden retrievers that were taurine-deficient.

Taurine is an amino acid, which is a building block of protein, necessary for heart health. It is normally found in animal tissue, including red meats, poultry and seafood. Taurine is not present in plant tissue. Although it is not considered to be an “essential” amino acid in the canine diet, some dry dog foods are supplemented with taurine.

Dogs that receive an adequate amount of the amino acids cysteine and methionine are able to produce taurine for themselves. Both cysteine and methionine are found in significant concentrations in meats, poultry, seafood and dairy products. These essential amino acids tend to be found at relatively lower concentrations in most edible plants, including peas, potatoes and lentils.

In four atypical cases of DCM reported to FDA, three golden retrievers and one Labrador retriever, blood tests revealed low whole blood levels of taurine. The Labrador retriever is recovering under veterinary treatment, including taurine supplementation and a change in diet.

Four other atypical DCM cases in a miniature schnauzer, a Shiuh Tzu and two Labrador retrievers, had normal blood taurine levels.

FDA has contacted pet food manufacturers to discuss the reports and to help further the investigation.

The FDA encourages pet owners and veterinary professionals to report cases of DCM in dogs suspected of having a link to diet by using the electronic Safety Reporting Portal or calling their state’s FDA Consumer Complaint Coordinators. See “How to Report a Pet Food Complaint” for additional instructions.