Association Between Interleukin-18 Level and Left Ventricular Mass Index in Hypertensive Patients

BACKGROUND AND OBJECTIVES: In clinical trials, hypertensive patients tend to have higher interleukin-18 (IL-18) concentrations than normotensive groups, but the relationship between IL-18 and left ventricular hypertrophy (LVH), which is a marker of end-organ damage, is not well studied. We aimed to investigate the relationship between IL-18 and LVH in apparently healthy subjects free of clinically significant atherosclerotic disease. SUBJECTS AND METHODS: We enrolled 198 subjects (102 women and 96 men) between May 2006 and March 2007, who were free of cardiovascular or immune diseases, but were suspected to have hypertension. Twenty-four-hour ambulatory blood pressure monitoring and two-dimensional echocardiography were performed. Lipid profiles, high-sensitivity CRP (hs-CRP), IL-18, and whole blood cell counts were measured for all subjects. RESULTS: White blood cell count, hs-CRP, left ventricular mass, left ventricular mass index (LVMI), and IL-18 were higher in the hypertensive group than in the normotensive group (p=0.045, p=0.004, p<0.0001, p=0.001, and p=0.017 respectively). Twenty-four hour day and night systolic and diastolic blood pressure averages were positively correlated with IL-18 level in the entire study population. In multivariate regression analysis, left ventricular mass index and hs-CRP level were independently associated with IL-18 level in both the hypertensive group and the entire study population (β=0.154, β=0.149 p=0.033, p=0.040 and β=0.151, β=0.155 p=0.036, p=0.032 respectively) CONCLUSION: We found that IL-18 level independently predicted LVMI in both the general population and in newly diagnosed hypertensive patients.