Association between Diabetes Mellitus, Hypothyroidism or Hyperadrenocorticism, and Atherosclerosis in Dogs

Abstract

The objective of this study was to determine whether dogs with atherosclerosis are more likely to have concurrent diabetes mellitus, hypothyroidism, or hyperadrenocorticism than dogs that do not have atherosclerosis. A retrospective mortality prevalence casecontrol study was performed. The study group included 30 dogs with histopathological evidence of atherosclerosis. The control group included 142 dogs with results of a complete postmortem examination, a final postmortem examination diagnosis of neoplasia, and no histopathological evidence of atherosclerosis. Control dogs were frequency matched for age and year in which the postmortem examination was performed. Proportionate changes in the prevalence of diabetes mellitus, hypothyroidism, and hyperadrenocorticism were calculated by exact prevalence odds ratios (POR), 95% confidence intervals (95% CI), and P values. Multiple logistic regression analysis was used to examine the combined effects of prevalence determinants while controlling for age and year of postmortem examination. Dogs with atherosclerosis were over 53 times more likely to have concurrent diabetes mellitus than dogs without atherosclerosis (POR ϭ 53.6; 95% CI, 4.6-627.5; P ϭ .002) and over 51 times more likely to have concurrent hypothyroidism than dogs without atherosclerosis (POR ϭ 51.1; 95% CI, 14.5-180.1; P Ͻ .001). Dogs with atherosclerosis were not found to be more likely to have concurrent hyperadrenocorticism than dogs that did not have atherosclerosis (POR ϭ 1.8; 95% CI, 0.2-17.6; P ϭ .59). Diabetes mellitus and hypothyroidism, but not hyperadrenocorticism, are more prevalent in dogs with atherosclerosis compared to dogs without atherosclerosis on postmortem examination.

The companion dog as a model for human aging and mortality

“…This is due at least in part to dogs having blood cholesterol profiles associated with a low risk of cardiovascular disease with elevated high‐density lipoprotein and reduced low‐density lipoprotein profiles (Tsutsumi, Hagi & Inoue, 2001). As a result, dogs do not develop atherosclerosis except in rare cases when a concurrent condition causes a dramatic increase in total cholesterol levels (e.g., diabetes and hypothyroidism) (Hess, Kass & Van Winkle, 2003). Given the lack of similarity between dogs and humans in patterns of cardiovascular disease and its attendant risks, some might argue that the dog is a less than ideal model for human vascular diseases.…”

Correspondência entre obesidade e hiperlipidemia em cães

“…Um estudo demonstrou que somente valores de colesterolemia superiores a 750mg dL -1 predispõe os cães a desenvolverem aterosclerose e animais nesse estado estão 53 vezes mais susceptíveis a desenvolverem Diabetes mellitus e 51 vezes mais predispostos ao hipotireoidismo (HESS et al, 2003 …”

Echocardiographic assessment of coronary artery flow in normal canines and model dogs with myocardial infarction

“…Changes in coronary blood flow are not only observed in cases of cardiovascular diseases such as hypertrophic cardiomyopathy [7,9,12,32] and mitral regurgitation [5,8,10,21,28,29], but also other pathologic conditions such as acute renal failure [18], chronic diabetes mellitus [13,15,31], and hypothyroidism [15,26]. In a previous study, dogs with acute renal failure had decreased or absent coronary flow reserve [18].…”

“…The risk of myocardial infarction is increased if elevated oxygen demand of the myocardium is not satisfied by the coronary blood supply due to endotherial dysfunction of the coronary artery [18]. A previous study reported that 20 out of 30 dogs with diabetes mellitus or hypothyroidism developed atherosclerosis in the coronary artery [15]. Another investigation found that coronary blood flow in dogs with hypothyroidism was reduced compared to that in normal dogs [26].…”