Prospective study of dilated cardiomyopathy in dogs eating nontraditional or traditional diets and in dogs with subclinical cardiac abnormalities

Abstract

Background Recent studies have investigated dogs with presumed diet‐associated dilated cardiomyopathy (daDCM), but prospective studies of multiple breeds are needed. Hypothesis/Objectives To evaluate baseline features and serial changes in echocardiography and cardiac biomarkers in dogs with DCM eating nontraditional diets (NTDs) or traditional diets (TDs), and in dogs with subclinical cardiac abnormalities (SCA) eating NTD. Animals Sixty dogs with DCM (NTD, n = 51; TDs, n = 9) and 16 dogs with SCA eating NTDs. Methods Echocardiography, electrocardiography, and measurement of taurine, cardiac troponin I, and N‐terminal pro‐B‐type natriuretic peptide were performed in dogs with DCM or SCA. Diets were changed for all dogs, taurine was supplemented in most, and echocardiography and cardiac biomarkers were reassessed (3, 6, and 9 months). Results At enrollment, there were few differences between dogs with DCM eating NTDs or TDs; none had low plasma or whole blood taurine concentrations. Improvement in fractional shortening over time was significantly associated with previous consumption of a NTD, even after adjustment for other variables (P = .005). Median survival time for dogs with DCM was 611 days (range, 2‐940 days) for the NTD group and 161 days (range, 12‐669 days) for the TD group (P = .21). Sudden death was the most common cause of death in both diet groups. Dogs with SCA also had significant echocardiographic improvements over time. Conclusions and Clinical Importance Dogs with DCM or SCA previously eating NTDs had small, yet significant improvements in echocardiographic parameters after diet changes.

Metabolomic profiling in dogs with dilated cardiomyopathy eating non-traditional or traditional diets and in healthy controls

“…Plasma samples from 75 dogs at baseline were analyzed. The commercial diets eaten by the dogs were categorized as NT if they were grain-free or included pulses or potatoes in the top 10 ingredients and T if they were grain-inclusive and had no pulses or potatoes in the top 10 ingredients 10 , 15 , 26 . We assessed the following groups: Dogs with DCM eating NT diets (DCM-NT [n = 38]), dogs with DCM eating T diets (DCM-T [n = 8]), healthy control dogs eating NT diets (C-NT [n = 12]), and healthy control dogs eating T diets (C-T [n = 17]).…”

“…Dogs with diet-associated DCM are clinically different from and have a different response to treatment compared to dogs with primary DCM 12 – 15 , 19 , supporting a different etiology of disease (i.e., diet, rather than genetic cause). Therefore, we next sought to understand whether pathways that distinguished (1) dogs with DCM from healthy dogs (regardless of baseline diet) differed from pathways that distinguished (2) dogs with DCM based on diet.…”

“…The cause of this current episode of secondary DCM is unknown but could be the result of a nutritional deficiency, a toxicity, or a combination of nutritional factors. Taurine deficiency, which can cause DCM in dogs and cats, appears to be uncommon in dogs with this form of DCM 12 – 15 . Deficiencies of other nutrients, such as thiamine, magnesium, choline, vitamin E, selenium, taurine, and L-carnitine, also have been associated with secondary DCM in humans or animal models 3 , 16 – 18 , but these nutrients do not appear to be deficient in the diets associated with this problem or in the small number of affected dogs that have been tested 15 .…”

“…The diets fed to dogs with diet-associated DCM are often "grain-free" and typically contain one or more pulses or pulse fractions (e.g., pea protein, fiber, starch) and, to a lesser degree, potatoes and sweet potatoes 12 – 15 , 19 . One study of nine diets commonly fed to dogs with diet-associated DCM and nine control diets identified four ingredients that significantly differentiated these two groups: peas and lentils (more common in the associated diets) and chicken/turkey and rice (less common in the associated diets) 20 .…”

“…One study of nine diets commonly fed to dogs with diet-associated DCM and nine control diets identified four ingredients that significantly differentiated these two groups: peas and lentils (more common in the associated diets) and chicken/turkey and rice (less common in the associated diets) 20 . While standard nutritional analyses have not identified a causative factor 15 , a recent small molecules “foodomics” analysis of diets identified 122 biochemical compounds that were higher and 27 biochemical compounds that were lower in diets associated with DCM compared to those that were unassociated 20 . Random forest analysis identified the top 30 compounds that distinguished the diet groups with 100% accuracy 20 .…”