Influence of Various Factors on Circulating 25(OH) Vitamin D Concentrations in Dogs with Cancer and Healthy Dogs

Abstract

BackgroundLow blood 25‐hydroxyvitamin D (25(OH)D) concentrations have been associated with cancer in dogs. Little research has examined what other factors may affect 25(OH)D concentrations.Objectives(1) To determine whether the presence of cancer (lymphoma, osteosarcoma, or mast cell tumor [MCT]) in dogs is associated with plasma 25(OH)D concentrations and (2) identify other factors related to plasma 25(OH)D concentrations in dogs.AnimalsDogs newly diagnosed with osteosarcoma (n = 21), lymphoma (n = 27), and MCT (n = 21) presented to a tertiary referral oncology center, and healthy, client‐owned dogs (n = 23).MethodsAn observational study design was used. Dietary vitamin D intake, sex, age, body condition score (BCS), muscle condition score (MCS), and plasma concentrations of 25(OH)D, 24,25‐dihydroxyvitamin D (24,25(OH)2D) (a marker of CYP24A1 activity), as well as ionized calcium (ICa), parathyroid hormone, and parathyroid hormone‐related protein concentrations were measured. An analysis of covariance was used to model plasma 25(OH)D concentrations.ResultsCancer type (P = 0.004), plasma 24,25(OH)2D concentrations (P < 0.001), and plasma ICa concentrations (P = 0.047) had significant effects on plasma 25(OH)D concentrations. Effects of age, sex, body weight, BCS, MCS, and plasma PTH concentrations were not identified. A significant interaction between ICa and cancer was found (P = 0.005). Plasma 25(OH)D concentrations increased as ICa concentrations increased in dogs with cancer, whereas plasma 25(OH)D concentrations decreased as ICa concentrations increased in healthy dogs.Conclusions and Clinical ImportanceResults support a relationship between cancer and altered vitamin D metabolism in dogs, mediated by plasma ICa concentrations. The CYP24A1 activity and plasma ICa should be measured in studies examining plasma 25(OH)D concentrations in dogs.

Vitamin D metabolism in dogs and cats and its relation to diseases not associated with bone metabolism

“…Weidner et al (2017) observed that dogs with lymphoma (n = 27), osteosarcoma (n = 21) and mastocytoma (n = 21) had lower serum 25(OH)D concentrations compared to a control group of healthy dogs. In this study, it was possible to collect samples of the foods consumed by the majority of dogs that participated in the experiment to analyse vitamin D levels.…”

“…The relationship of vitamin D and diseases has also been investigated in dogs and cats, and some studies found association between low vitamin D status and some types of cancer (Selting, Sharp, Ringold, Thamm, & Backus, 2016;Wakshlag et al, 2011;Weidner et al, 2017), congestive heart failure (Kraus et al, 2014;Osuga et al, 2015), gastrointestinal diseases (Allenspach, Rizzo, Jergens, & Chang, 2017;Gow et al, 2011;Lalor et al, 2014;Titmarsh, Gow, Kilpatrick, Cartwright, et al, 2015;Titmarsh, Gow, Kilpatrick, Sinclair, et al, 2015), acute pancreatitis (Kim et al, 2017), acute polyradiculoneuritis (Laws, Kathrani, Harcourt-Brown, Granger, & Rose, 2018), chronic kidney disease (Cortadellas, Fernandez del Palacio, Talavera, & Bayón, 2010;Galler et al, 2012;Gerber, Hässig, & Reusch, 2003;Gerber, Hauser, & Reusch, 2004;Parker, Harjes, et al, 2017) and infectious diseases (Lalor et al, 2012;Rodriguez-Cortes et al, 2017;Rosa, Schoeman, Berry, Mellanby, & Dvir, 2013;. Although these studies do not prove a cause-effect relationship, they provide a basis for future studies to investigate possible positive effects of vitamin D supplementation on improving health status and reducing the risk of developing diseases.…”

Vitamin D Metabolism and Profiling in Veterinary Species

“…Numerous studies have shown that vitamin D deficiency is associated with skeletal and non-skeletal disease in companion animals [19][20][21][22][23][24][25][26][27][28][29] and reproductive outcomes in farm animals [30].…”

Effects of body fat mass and therapeutic weight loss on vitamin D status in privately owned adult dogs

“…Despite the prevalence of canine obesity and research demonstrating the occurrence of systemic inflammation in obese dogs, to our knowledge, the relationship between vitamin D status and obesity in dogs has not been investigated ( 27 – 29 ) . In a recently published study evaluating plasma 25(OH)D concentrations in sixty-nine dogs with cancer and twenty-three healthy control dogs, a significant relationship between body condition score (BCS) and vitamin D status was not found ( 30 ) . The majority of dogs in the study were in ideal body condition or overweight, and the number of obese subjects was not described ( 30 ) .…”

“…In a recently published study evaluating plasma 25(OH)D concentrations in sixty-nine dogs with cancer and twenty-three healthy control dogs, a significant relationship between body condition score (BCS) and vitamin D status was not found ( 30 ) . The majority of dogs in the study were in ideal body condition or overweight, and the number of obese subjects was not described ( 30 ) . One goal of the present study was to assess the relationship between adiposity and vitamin D status (as indicated by serum 25-hydroxyvitamin D 3 (25(OH)D 3 ) and 24,25-dihydroxyvitamin D 3 (24,25(OH) 2 D 3 ) concentrations) in otherwise healthy adult dogs in ideal, overweight or obese body condition.…”