OP-035 CHANGE IN APELIN LEVEL IN RESPONSE TO TREATMENT AND RELATION WITH DIASTOLIC FUNCTION IN PATIENTS WITH NEWLY DIAGNOSED HYPERTENSION

Abstract

Objective: Apelin is a novel endogenous peptide which has different functions in cardiovascular system. In this study we aimed to investigate the change in apelin levels in patients with newly diagnosed hypertension after one month of drug therapy and identify the relation between apelin level and improvement in left ventricular diastolic function. Methods: This study included 45 patients (26 men, 19 women) who were diagnosed as stage 1 and 2 hypertension based on Eurepean Society of Cardiology guidelines. Patients who had coronary artery disease, diabetes mellitus, severe valvular disease, body mass index above 30 kg/ m, left ventricle ejection fraction below 45% and creatinine level above 1.6mg/dl were excluded. Patients were randomized to treatment groups of 80mg telmisartan and 10mg amlodipine. At baseline, blood samples for apelin level were obtained and transthoracic echocardiography was performed. In addition to routine echocardiographic measurements, lateral and septal annular e′ wave velocities were measured using tissue Doppler method and their mean were used in statistical analysis. Transmitral flow propagation velocity (Vp) was measured by M-mode echocardiography. After 1 month of treatment, plasma apelin level measurement and echocardiography were repeated. Results: There were 24 patients in the telmisartan and 21 patients in the amlodipine group. Mean age, gender, baseline blood pressure and apelin levels were similar between the groups (p > 0.05). There was a significant increase in apelin levels for all patients after one month of treatment (0.41±0.06 vs 0.46±0.07ng/dl, p = 0.003). When each group were evaluated separately, apelin was significantly increased in both telmisartan (0.39±0.06 vs 0.46±0.08ng/ dl, p = 0.04) and amlodipine groups (0.42±0.05 vs 0.46±0.06ng/dl, p = 0.02). Left atrial volume (38.8±6.9 vs 35.8±6.0ml, p < 0.001), isovolumetric relaxation time (98±15ms vs 90±12ms, p < 0.001) and E/e′ ratio (8.6±1.7 vs 7.0±1.4, p < 0.001) were decreased; Vp (43.4±8.2 vs 47.0±8.3 cm/s, p< 0.001) and mean e′ velocity (8.2±1.8 vs 9.8±1.9 cm/s, p < 0.001) were increased significantly. Similar results were obtained when telmisartan and amlodipine groups were analyzed separately. After treatment, apelin levels showed a significant reverse correlation with mitral deceleration time (r = −0.39, p = 0.02). Conclusion: Apelin levels were increased in newly diagnosed hypertensive patients after antihypertensive therapy. Apelin may be a useful marker for evaluating the efficacy of antihypertensive treatment. Further studies are needed to establish the relation between apelin levels and diastolic indices.