老年心力衰竭患者体重指数与心率变异性关系的研究

Correlation between body mass index and heart rate variability in senile patients with heart failure

目的探讨体重指数(BMI)对老年心力衰竭患者的心率变异性(HRV)及临床指标的影响。方法选取老年慢性心力衰竭(CHF)患者55例(左心室射血分数<45%),根据BMI分为3组:轻-正常体重组,超重组和肥胖组,对3组患者进行HRV的时域指数、B型尿钠肽(BNP)和肺动脉压力检查,所得结果与BMI进行相关性分析。结果 HRV各测值均随BMI的下降而呈递减性下降,在3组间差异均有统计学意义(P<0.05或0.01)。BMI与SDNN呈正相关(r=0.40,P<0.01),SDNN与肺动脉压力呈负相关(r=-0.388,P<0.05),BNP与BMI呈负相关(r=-0.421,P<0.01)。结论老年心力衰竭患者存在自主神经功能的受损和失衡,与BMI的下降密切相关。BMI的测定有助于老年心力衰竭患者的严重程度与预后的评估以及治疗的指导。

Objective To investigate the correlation of body mass index（BMI） with heart rate variability（HRV） in senile pa-tients with heart failure. Methods Clinical data of 55 consecutive senile patients with symptomatic left ventricular systolic heart failure（ejection fraction〈45%） were retrospectively analyzed. Patients were classified into lean, overweight and and obese groups according to BMI. Serum brain natriuretic peptide（BNP） level and pulmonary artery pressure（PAP） were measured, and time- domain HRV indices were determined on Holter electrocardiogram. The relationship of BMI with HRV and PAP was analyzed. Results The indicators of HRV decreased gradual y with the decreasing of BMI, and there were significant differences in indicators of HRV among three groups（P〈0.05 or 0.01）. BMI was positively correlated with the decrease of SDNN（r=0.40, P〈0.01）;the decrease of SDNN was negatively correlated with PAP （r=- 0.388, P〈0.05）, serum BNP level was negatively correlated with BMI （r=- 0.421, P〈0.01）. Conclusion The impairment and imbalances of automatic nervous system in senile patients with CHF are closely correlated with BMI decrease. Determination of BMI is helpful for evaluations of severity, prognosis and treatments of heart failure in senile patients.