Does feline hypertension raise your blood pressure?

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Systemic hypertension is a common, often underdiagnosed issue in cats that can have devastating effects on the brain, eyes, kidneys, and heart. Causes of hypertension can be classified as idiopathic (primary), secondary, or situational.^1-3 Because the risk of hypertension increases with age and comorbidities, screening for systemic hypertension is recommended annually for any patient over age 7.^4-6 

Systemic hypertension is diagnosed when systolic blood pressure readings are >160 mmHg. In these cases, the patient should return for a separate visit to repeat measurements and determine if the hypertension is situational.¹ Situational hypertension is something we all understand as a response to acute excitement or anxiety that resolves once the stimulus is removed. Additionally, generalized anxiety and chronic pain conditions such as osteoarthritis and periodontal disease can contribute and should be addressed.¹ Using a feline friendly handling technique, in a calm, quiet environment, the risk of situational hypertension is reduced.^1,5,7

Once systemic hypertension is confirmed, the next step is to determine whether it is secondary or idiopathic. Diagnostics including complete blood cell count, biochemistry, TT4, urinalysis, and thoracic radiography/echocardiogram should be evaluated to screen for renal insufficiency, hyperthyroidism, diabetes and cardiomyopathy, as these are common causes of secondary hypertension.^1-3,5,6 Other methods of identifying risk factors for secondary hypertension include genetic testing to identify markers for hypertrophic cardiomyopathy or polycystic kidney disease. Additionally, a new, noninvasive, oral swab-based screening tool that evaluates the oral microbiome and associated risk of developing kidney disease is currently in development.⁸

Idiopathic hypertension should be suspected if lab work and imaging are unremarkable. Idiopathic hypertension accounts for approximately 13% to 20% of hypertension cases and is a diagnosis of exclusion.^2,3,5 It is important to note that chronic hypertension may induce polyuria secondary to pressure diuresis, resulting in a low urine specific gravity (<1.030) and this finding can make it difficult to establish whether underlying kidney disease is present.³

In conclusion, regardless of the cause, a diagnosis of systemic hypertension should always be confirmed with repeat blood pressure measurements at a separate visit, prior to starting medical therapy.¹ The exception would be when there is evidence of target organ damage particularly involving the eyes (blindness, retinal edema, hemorrhage, or detachment), neurologic system (disorientation, seizures, ataxia, depression, or vestibular signs), and/or heart (arrhythmias or congestive heart failure).^2,5 In these emergency cases, treatment should be initiated without delay, and the patient closely monitored. Several published guidelines and toolkits are available with more guidance on the diagnosis and treatment of feline hypertension.^1,3,5

References:

1. Hypertension Educational Toolkit. AAFP. 2021. Accessed March 8, 2023. https://catvets.com/hypertension-toolkit
2. Maggio F, DeFrancesco TC, Atkins CE, et al. Ocular lesions associated with systemic hypertension in cats: 69 cases (1985-1998). J Am Vet Med Assoc. 2000 Sep 1;217(5):695-702.
3. Acierno MJ, Brown S, Coleman AE, et al. ACVIM consensus statement: guidelines for the identification, evaluation, and management of systemic hypertension in dogs and cats. J Vet Intern Med 2018; 32: 1803–1822.
4. Quimby J, Gowland S, Carney HC, et al. 2021 AAHA/AAFP Feline Life Stage Guidelines. J Feline Med Surg. 2021;23(3):211-233.
5. Taylor SS, Sparkes AH, Briscoe K, et al. ISFM Consensus Guidelines on the Diagnosis and Management of Hypertension in Cats. J Feline Med Surg. 2017;19(3):288-303.
6. Bijsmans ES, Jepson RE, Chang YM., et al. Changes in systolic blood pressure over time in healthy cats and cats with chronic kidney disease. J Vet Intern Med. 2015; 29: 855–861.
7. Rodan I, Dowgray N, Carney HC, et al. 2022 AAFP/ISFM Cat Friendly Veterinary Interaction Guidelines: Approach and Handling Techniques. J Feline Med Surg. 2022;24(11):1093-1132.
8. "Chronic Kidney Disease Research in Cats." Basepaws, October 26, 2021. Accessed February 14, 2023. https://basepaws.com/blogs/news/chronic-kidney-disease-research-at-basepaws