Cardiovascular effects of dietary salt intake in aged healthy cats: a 2-year prospective randomized, blinded, and controlled study

• Published in: PloS one 2014-06, Vol.9 (6), p.e97862-e97862
• Main Authors: Chetboul, Valérie, Reynolds, Brice Stéphane, Trehiou-Sechi, Emilie, Nguyen, Patrick, Concordet, Didier, Sampedrano, Carolina Carlos, Testault, Isabelle, Elliott, Jonathan, Abadie, Jérôme, Biourge, Vincent, Lefebvre, Hervé Pierre
• Format: Article
• Language: English
• Subjects: Aging; Aging - physiology; Animal models; Animals; Biology and Life Sciences; Blood; Blood Flow Velocity - drug effects; Blood Flow Velocity - physiology; Blood pressure; Blood Pressure - drug effects; Blood Pressure - physiology; Calcium; Calcium (urinary); Cardiomyopathy; Cardiovascular disease; Cats; Chlorides; Diastole; Diet; Dietary intake; Doppler effect; Echocardiography; Female; Food science; Geriatrics; Health care; Heart; Heart - drug effects; Heart - physiology; Hypertension; Kidney diseases; Laboratory animals; Life Sciences; Male; Medicine and Health Sciences; Nutrition research; Older people; Oxalates; Pressure measurement; Randomization; Salts; Septum; Sodium; Sodium Chloride, Dietary - pharmacology; Studies; Systematic review; Systole; Ultrasonic imaging; Urinary tract diseases; Urine; Urogenital system; Ventricle; Ventricular Function, Left - drug effects; Ventricular Function, Left - physiology; Veterinary colleges; Veterinary medicine; Water intake; Water intakes
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0097862

High salt dry expanded diets are commercially available for cats to increase water intake and urine volume, as part of the prevention or treatment of naturally occurring urinary stone formation (calcium oxalates and struvites). However, chronic high salt intake may have potential cardiovascular adverse effects in both humans, especially in aging individuals, and several animal models. The objective of this prospective, randomized, blinded, and controlled study was to assess the long-term cardiovascular effects of high salt intake in healthy aged cats. Twenty healthy neutered cats (10.1 ± 2.4 years) were randomly allocated into 2 matched groups. One group was fed a high salt diet (3.1 g/Mcal sodium, 5.5 g/Mcal chloride) and the other group a control diet of same composition except for salt content (1.0 g/Mcal sodium, 2.2 g/Mcal chloride). Clinical examination, systolic and diastolic arterial blood pressure measurements, standard transthoracic echocardiography and conventional Doppler examinations were repeatedly performed on non-sedated cats by trained observers before and over 24 months after diet implementation. Radial and longitudinal velocities of the left ventricular free wall and the interventricular septum were also assessed in systole and diastole using 2-dimensional color tissue Doppler imaging. Statistics were performed using a general linear model. No significant effect of dietary salt intake was observed on systolic and diastolic arterial blood pressure values. Out of the 33 tested imaging variables, the only one affected by dietary salt intake was the radial early on late diastolic velocity ratio assessed in the endocardium of the left ventricular free wall, statistically lower in the high salt diet group at 12 months only (P = 0.044). In conclusion, in this study involving healthy aged cats, chronic high dietary salt intake was not associated with an increased risk of systemic arterial hypertension and myocardial dysfunction, as observed in some elderly people, salt-sensitive patients and animal models.