ABSTRACT
Objective To explore the change in plasma B-type natriuretic peptide (BNP) concentration and its potential influencing factors in elderly patients with hypertension.Methods A total of 137 patients with hypertension [75 males,62 females,aged (78.3±7.5) years] were enrolled in this study.Patients were divided into 3 groups:simple hypertension (SH) group (n=36),hypertension combined with cardiac structural changes (HCSC) group (n=31),and hypertension combined with systolic heart failure (HHF) group (n=70).Plasma BNP concentration was measured by immunofluorescence antibody method.Cardiac structure and function parameters in patients were detected by echocardiography within 24-48 hours after taking blood samples.Data was analyzed by SPSS 16.0.Results There were significant differences in the value of lgBNP among HHF,HCSC and SH groups (2.8±0.4,2.0±0.5,1.9±0.5,respectively,F 61.69,P＜0.05).Multiplelinear regression analysis showed that left atrial diameter (LAD),left ventricular ejection fraction (LVEF),age,LVMI (left ventricular mass index) and pulse pressure (PP) were the five effective variables of the lgBNP (F=58.69,P＜0.05) in HCSD group and SH group.The regression equation was:lgBNP=0.010X1 +0.007X2-0.054X3 +0.049X1 +0.013X5 +2.635 (X1 represented as PP,X2 as age,X3 as LVEF,X4 as LAD and X5 as LVMI).The standardized regression coefficient of X1 to X5 was0.446,0.235,-0.621,0.574 and 0.457,respectively.The value of lgBNP in patients with normal contractile function was higher in patients with late diastolic mitral flow velocity ratio (E/A)＜1 than in those with E/A＞1 (2.42±0.35 vs.2.25±0.16,t=0.94,P＜0.05).Conclusions The plasma BNP concentration is negatively correlated with LVEF and positively correlated with LAD,PP,age and LVMI in elderly patients with hypertension.The effect degree from great to little in line was LVEF,LAD,LVMI,PP and age.In addition,there is a negative correlation between plasma BNP concentration and E/A ratio in patients with normal contractile function.