Association between salt sensitivity and target organ damage in essential hypertension

Cardiovascular events occur more frequently in sodium-sensitive patients wi th essential hypertension; recently, sodium sensitivity was shown to be a c ardiovascular risk factor independently of other classic factors such as bl ood pressure and cigarette smoking This study examined the relationship bet ween salt sensitivity status and target organ damage in hypertensive patien ts. Ninety-six patients (35 men, 61 women) with moderate essential hyperten sion were studied for salt sensitivity status and the presence of target or gan damage, including hypertensive retinopathy, serum creatinine, creatinin e clearance, and urinary albumin excretion (UAE). Four different patterns o f left ventricular anatomic adaptation were identified by categorizing pati ents according to the values of left ventricular mass index and relative wa ll thickness by the means of echocardiography. Forty-five (47%) patients we re shown to be salt-sensitive, in contrast to 51 (53%) salt-resistant subje cts. Serum creatinine and UAE were significantly higher in the group of sal t-sensitive hypertensives (P < .05 and P < .001, respectively). Left ventri cular mass index (LVMI), relative wall thickness (RWT), and left atrial ind ex (LAI) were all significantly higher in the group of salt-sensitive hyper tensive patients. Concentric hypertrophy was significantly more prevalent i n the salt-sensitive group (37.8% v 11.8%; P < .01). The prevalence of hype rtensive retinopathy in the salt-sensitive group was 84.4%, in contrast to 59.6% in the salt-resistant group (P < .01). Multivariate regression analys is revealed salt sensitivity as a significant predictor of LVMI, RWT, and U AE, independently of age, body mass index, and mean blood pressure. In conc lusion, salt-sensitive hypertensive patients are more prone to develop seve re hypertensive target organ damage that may enhance their risk of renal an d cardiovascular morbidity. (C) 2000 American Journal of Hypertension, Ltd.