原发性高血压患者摄氧效率斜率与体质量指数的相关性

The Relationship Between Oxygen Uptake Efficiency Slope and Body Mass Index in Patients with Essential Hypertension

目的探讨原发性高血压(EH)患者摄氧效率斜率(OUES)与体质量指数(BMI)的相关性。方法入选健康成人32例和EH患者56例,按BMI将EH患者分为3个亚组:体质量正常组(BMI18.5～23.9kg/m2,18例),超重组(BMI24.0～27.9kg/m2,18例)和肥胖组(BMI≥28.0kg/m2,20例)。采用症状限制性标准Bruce分级平板运动方案,同时测定气体代谢指标摄氧量、二氧化碳排出量、峰值摄氧量(VO2peak)、每分通气量(VE)、呼吸气体交换率(RER)。根据心肺运动试验的实测数据,采用对数曲线拟合的方法,分析递增负荷运动试验中摄氧量与VE的关系,建立回归方程,摄氧量=a×lgVE+b,计算a为OUES值。运动过程中摄氧量为75%VO2peak,90%VO2peak和100%VO2peak时的OUES值分别表示为OUES75、OUES90、OUES100。采用Hollenberg等提出的预测公式计算OUES100的预计值(preOUES100)。结果递增负荷运动试验中,EH超重组和EH肥胖组的OUES100、OUES90、OUES75均高于对照组及EH体质量正常组,EH肥胖组与EH超重组之间比较无统计学差异。EH肥胖组preOUES100高于其他各组。BMI与OUES100呈正相关(r=0.414,P<0.01),与preOUES100、OUES90和OUES75之间也呈正相关。结论EH患者BMI与OUES呈正相关,随着BMI增加,OUES得到一定改善,但伴有肥胖的EH患者OUES未比超重者有进一步改善。

Objective To investigate the relationship between the oxygen uptake efficiency slope （OUES） and body mass index （BMI） in patients with essential hypertension （EH）.MethodsExercise tests following a symptom-limited standard Bruce protocol with simultaneous respiratory gas-exchange measurements were performed on a treadmill in 32 healthy adults free of clinically recognized cardiovascular disease, and 56 patients with EH, in which 18 patients were in normal weight, 18 overweight and 20 obesity. The OUES was derived from the relation between oxygen uptake （VO2） and minute ventilation （VE） during incremental exercise and was determined by VO2= a lg VE＋b, where a=OUES.The OUES was calculated from data of the first 75%（OUES75）, 90% （OUES90） and 100%（OUES100） of exercise duration.Predicted OUES100（preOUES100） was calculated according to the Hollenberg equations.ResultsThe OUES100, OUES90 and OUES75 were higher in EH overweight group and EH obese group than control group and EH normal weight group. However, they were not different between EH obese group and overweight group. The preOUES100 was higher in EH obese group than that in other groups. There was a significant correlation between BMI and the OUES100 （r=0.414,P〈0.01）, and a correlation between BMI and the preOUES100, OUES90 or the OUES75.ConclusionOUES correlates with BMI in EH. The OUES appears to be improved with body weight in EH patients, but it does not appear to be improved in obese patients with EH.