OP3 Retrospective evaluation of systemic hypertension in dogs with non-associative (primary) immune-mediated haemolytic anaemia

Abstract

Background Immune-mediated haemolytic anaemia (IMHA) is a common autoimmune condition in dogs associated with a high rate of morbidity and mortality. Further work is required to understand the systemic consequences of IMHA and identify novel therapeutic targets. Hypertension is a negative prognostic indicator in people with autoimmune disease. There is increasing evidence that hypertension has an inflammatory aetiopathogenesis and responds favourably to immunosuppressive treatment. However, the prevalence and clinical signifiance of hypertension in canine IMHA has not been investigated. Study Aims Determine the prevalence of hypertension in dogs with IMHA, and the relationships of systolic blood pressure (SBP) and hypertension with short-term mortality. Design and Methods Retrospective study in university teaching veterinary hospital intensive care unit. Dogs with IMHA were compared with a control group of dogs with idiopathic epilepsy. Hypertension was defined as SBP ≥160 mmHg and severe hypertension as SBP ≥180 mmHg. Patient data, treatments and within-hospital mortality were recorded. Comparisons between IMHA and control groups were made for SBP (independent t-test) and hypertension (Fisher’s exact test). In-patient mortality was compared between hypertensive and normotensive IMHA dogs by Fisher’s exact test. Results SBP was increased in 26 dogs with IMHA (161 mmHg SD 21) compared to 23 control dogs (138 mmHg SD14; P Conclusion IMHA is a risk factor for hypertension but hypertension does not predict short-term mortality in IMHA. Hypertension in dogs may also have an inflammatory aetiology and canine IMHA has translatable potential as a naturally occurring model of hypertension in autoimmune disease.