The effect of obesity and subsequent weight reduction on cardiac structure and function in dogs

Overweight and obese body condition in ∼4.9 million dogs and ∼1.3 million cats seen at primary practices across the USA: Prevalences by life stage from early growth to senior

Adult dogs and cats in overweight or obese condition are common, but prevalence data for different life stages, especially growth, are limited, and may help inform when preventative measures may be most effective. In this retrospective observational study, prevalences of overweight and obese condition were determined from the electronic medical records of dogs and cats of all life stages visiting Banfield Pet Hospital in the USA between 2020 and 2023. Animals were identified either by body condition score (BCS; overweight 6-7; obese 8-9) or from a clinical diagnosis of overweight condition or obesity when recorded. Life stages (early growth, late growth, young adult, adult, mature, and senior) were defined by age range, adjusted for species and breed size in dogs. Individuals could only be included once within each life stage, with the maximum BCS used. Prevalence was determined for the 4-year period and for each calendar year. The evolution of BCS was also assessed for animals with multiple records. In total, 4933,916 unique dogs and 1341,118 unique cats were included. In dogs, prevalences of overweight or obese condition were: 0.9 % and < 0.0 % (early growth), 9.5 % and 0.3 % (late growth), 24.4 % and 1.9 % (young adult); 44.5 % and 8.4 % (adult), 50.1 % and 12.6 % (mature); 46.4 % and 11.3 % (senior). In cats, prevalences of overweight or obese condition were: 0.8 % and < 0.0 % (early growth); 10.7 % and 0.4 % (late growth); 36.2 % and 3.6 % (young adult); 47.2 % and 13.9 % (adult); 44.8 % and 21.7 % (mature); and 32.0 % and 12.6 % (senior). From 2020-2021 and 2021-2022 prevalences of overweight and obese condition in dogs and overweight condition in cats increased in most life stages. The prevalence of overweight condition in dogs and obese condition in cats and dogs significantly decreased between 2022 and 2023 for some life stages. The odds ratio of an overweight or obese condition in adulthood was 1.85 (95 % confidence interval [CI]: 1.81, 1.86); P ≤ 0.001) for dogs and 1.52 (95 % CI: 1.48, 1.56; P ≤ 0.001) for cats where an overweight or obese condition was recorded during growth. In conclusion, both overweight and obese condition are prevalent throughout adult life, peaking during the mature life stage in dogs and cats, with overweight or obese condition during growth persisting into adulthood in most affected animals. Veterinarian-led prevention strategies are recommended from growth onwards, including the use of growth standard charts.

Prevalence and factors associated with overweight and obesity in dogs presenting to French university veterinary teaching hospitals during the COVID-19 pandemic

Pet obesity is still a major health issue, which is considered an epidemic by some researchers. Prevention is one of the cornerstones of veterinary care, emphasizing the importance of proactive measures. Human lifestyle was affected during the COVID-19 pandemic, resulting in an increased overweight prevalence in the population. The prevalence of overweight and obesity in dogs during this period has been poorly explored. This study's objectives were to assess the percentage of the French dog population with overweight and obesity, compare the results with a study conducted before the COVID-19 pandemic, and investigate any potential changes in the risk factors. The study collected data through a survey completed by dog owners during their pets' vaccination visits at university veterinary hospitals of Maisons-Alfort (Paris) and Toulouse, in France, between 2020 and 2022. The veterinarian recorded the dog's weight and the body condition score using a 9-point scale. The study included a total of 309 dogs. Of these, 1.6 % were underweight, 63.1 % had an ideal body condition, and 35.3 % were overweight, including 2.3 % of all dogs classified as obese. During the pandemic, French dog diets shifted towards increased commercial food consumption and twice-daily feedings compared to a 2003 study. Factors positively associated with overweight were being female (OR = 3.55; 95 % CI: 1.65-8.01; P=0.002), being senior (OR=4.91; 95 % CI: 2.07-12.2; P<0.001) or geriatric (OR=5.81; 95 % CI: 2.04-17.0; P=0.001) and having an owner underestimating dog's body condition (OR=74.1; 95 % CI: 29.8-215; P<0.001). Recognizing the impact of owner perception enables early intervention strategies, such as educating owners during consultations and conducting teaching sessions at the clinic. This proactive approach could contribute to improved health outcomes and help prevent the onset of obesity-related issues in dogs. The new trends in dogs' diets may have global relevance due to the pandemic's widespread impact. Although no immediate impact on overweight is evident, ongoing research is crucial to understand the pandemic's long-term effects.

The effect of obesity and subsequent weight reduction on cardiac morphology and function in cats

BACKGROUND

In people, obesity is a risk factor for cardiovascular disease, associated with systemic hypertension, cardiac remodelling and systolic and diastolic dysfunction. Weight reduction can reverse myocardial remodelling and reduce risk of subsequent cardiovascular disease. In cats, far less is known regarding the effects of obesity and subsequent weight reduction on cardiovascular morphology and function. This prospective study aimed to assess cardiac morphology and function, heart rate variability, cardiac biomarkers and body composition before and after controlled weight reduction in cats with obesity. Body composition analysis (by dual energy x-ray absorptiometry, DEXA) and cardiovascular assessment (echocardiography, systemic arterial systolic blood pressure, electrocardiography, plasma cardiac biomarkers) were performed prior to weight management in twenty cats with obesity. These investigations were repeated in eleven cats that reached target weight.

RESULTS

At baseline, systemic hypertension was not documented, but the majority of cats with obesity (15 out of 19) showed echocardiographic evidence of diastolic dysfunction. Eleven of 20 cats had increased maximal end-diastolic septal or left ventricular free wall thickness (≥ 6.0 mm) at baseline. Median (interquartile range) percentage of weight lost in the cats reaching target weight was 26% (17-29%), with a median reduction in body fat mass of 45% (26-64%). Both the end-diastolic left ventricular free wall (median magnitude of change -0.85 mm, IQR -0.05 mm to -1.55 mm, P = 0.019; median percentage reduction 14.0%) and end-diastolic interventricular septum (median magnitude of change -0.5 mm, IQR -0.2 mm to -1.225 mm, P = 0.047; median percentage reduction 7.9%) thickness decreased after weight reduction. Following weight reduction, pulsed wave tissue Doppler imaging of the left ventricular free wall was consistent with improved diastolic function in 4 out of 8 cats, however there was no significant difference in overall diastolic function class. Further, there was no change in heart rate variability or cardiac biomarkers with weight reduction.

CONCLUSION

An increase in left ventricular wall thickness and diastolic dysfunction were common echocardiographic features in cats with obesity within our study and may be reversible with successful weight and fat mass loss. Further studies are required to clarify the clinical consequences of these findings.

Different Diet Energy Levels Alter Body Condition, Glucolipid Metabolism, Fecal Microbiota and Metabolites in Adult Beagle Dogs

Diet energy is a key component of pet food, but it is usually ignored during pet food development and pet owners also have limited knowledge of its importance. This study aimed to explore the effect of diet energy on the body condition, glucolipid metabolism, fecal microbiota and metabolites of adult beagles and analyze the relation between diet and host and gut microbiota. Eighteen healthy adult neutered male beagles were selected and randomly divided into three groups. Diets were formulated with three metabolizable energy (ME) levels: the low-energy (Le) group consumed a diet of 13.88 MJ/kg ME; the medium-energy (Me) group consumed a diet of 15.04 MJ/kg ME; and the high-energy (He) group consumed a diet of 17.05 MJ/kg ME. Moreover, the protein content of all these three diets was 29%. The experiment lasted 10 weeks, with a two-week acclimation period and an eight-week test phase. Body weight, body condition score (BCS), muscle condition score (MCS) and body fat index (BFI) decreased in the Le group, and the changes in these factors in the Le group were significantly higher than in the other groups (p < 0.05). The serum glucose and lipid levels of the Le and He groups changed over time (p < 0.05), but those of the Me group were stable (p > 0.05). The fecal pH of the Le and He groups decreased at the end of the trial (p < 0.05) and we found that the profiles of short-chain fatty acids (SCFAs) and bile acids (BAs) changed greatly, especially secondary BAs (p < 0.05). As SCFAs and secondary BAs are metabolites of the gut microbiota, the fecal microbiota was also measured. Fecal 16S rRNA gene sequencing found that the Me group had higher α-diversity indices (p < 0.05). The Me group had notably higher levels of gut probiotics, such as Faecalibacterium prausnitzii, Bacteroides plebeius and Blautia producta (p < 0.05). The diet-host-fecal microbiota interactions were determined by network analysis, and fecal metabolites may help to determine the best physical condition of dogs, assisting pet food development. Overall, feeding dogs low- or high-energy diets was harmful for glucostasis and promoted the relative abundance of pathogenic bacteria in the gut, while a medium-energy diet maintained an ideal body condition. We concluded that dogs that are fed a low-energy diet for an extended period may become lean and lose muscle mass, but diets with low energy levels and 29% protein may not supply enough protein for dogs losing weight.

Causal effect of central obesity on left ventricular structure and function in preserved EF population: A Mendelian randomization study

Background

Observational studies have shown that central obesity is associated with adverse cardiac structure and function. However, causal association between central obesity and left ventricular (LV) structure and function in preserved ejection fraction (EF) population is still uncertain.

Methods

Genome-wide association studies summary data of waist circumference adjusted for body mass index (WCadjBMI) and waist-to-hip ratio adjusted for body mass index (WHRadjBMI) were selected as instrumental variables from the Genetic Investigation of Anthropometric Traits (GIANT) Consortium (n = 224,459). Outcome datasets for LV parameters including LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV ejection fraction (LVEF), LV mass (LVM), and LV mass-to-end-diastolic volume ratio (LVMVR) were obtained from the participants without prevalent myocardial infarction or heart failure (LVEF ≥ 50%) in UK Biobank Cardiovascular Magnetic Resonance sub-study (n = 16,923). Two-sample Mendelian randomization (MR) was performed with the inverse-variance weighted (IVW) method as the primary estimate and with the weighted median and MR-Egger as the supplemental estimates. Sensitivity analysis was used to assess the heterogeneity and pleiotropic bias in the MR results.

Results

In the IVW analysis, every 1-standard deviation (SD) higher WHRadjBMI was significantly associated with higher LVMVR (β = 0.4583; 95% confidence interval [CI]: 0.2921 to 0.6244; P = 6.418 × 10^-8) and lower LVEDV (β = -0.2395; 95% CI: -0.3984 to -0.0807; P = 0.0031) after Bonferroni adjustment. No heterogeneity and horizontal pleiotropy were detected in the analysis. No association of WCadjBMI was found with LVEF, LVEDV, LVESV, LVM, or LVMVR.

Conclusion

Our findings provide evidence of significant causal association between WHRadjBMI and adverse changes in LV structure and function in preserved EF population.