Effect of olmesartan medoxomil on cystatin C level, left ventricular hypertrophy and diastolic function

Serum cystatin C concentration is an alternative measure of kidney function that is less affected by age, sex or muscle mass, and is a more sensitive indicator of early renal dysfunction than creatinine-based estimations of glomerular filtration rate. Cardiovascular sequela increases progressively with the increase in left ventricular mass. Our goal was to evaluate the effect of olmesartan medoxomil on cystatin C levels and left ventricular hypertrophy (LVH) in patients with hypertension. Forty-four newly diagnosed hypertensive patients (27 women and 17 men) were recruited in the study. Olmesartan medoxomil (20mg/day) was started and the patients were followed up for 6 months. Baseline echocardiographic findings (i.e. left ventricular mass index), serum creatinine, urine albumin/creatinine ratio (ACR) and serum cystatin C levels were compared with the levels of these variables measured at the end of 6-month follow-up period. After 6 months of treatment with olmesartan medoxomil, there was a significant reduction in systolic and diastolic blood pressure (p<0.001) and in urine ACR (p=0.04). Mean serum cystatin C levels decreased from 1.61+/-0.24 mg/l to 1.31+/-0.29 mg/l (p<0.001). Olmesartan medoxomil treatment also reduced left ventricular mass index (p<0.001) and LVH (p<0.001). Our findings indicate that olmesartan medoxomil decreases serum cystatin C levels, urine ACR and reduces LVH in patients with hypertension. To our knowledge, this study is the first to show that olmesartan medoxomil decreases serum cystatin C levels, indicating that in patients with essential hypertension it may counteract end organ damage.