Correlation between Exercise Stress Test and Echocardiographic Parameters in Elderly Individuals

Abstract Background: Maximum oxygen consumption (VO2 max) in healthy individuals decreases approximately 10% per decade of life, and such decrease is more pronounced after the seventh decade. Objectives: To assess functional capacity of individuals aged 75 years or older, submitted to ergometric test and transthoracic echocardiogram exam, by means of metabolic equivalent (MET) and VO2 max measurements. Methods: A total of 381 patients (205 women; 79 ± 3.7 years) were evaluated. Exclusion criteria were: presence of left ventricular (LV) systolic dysfunction, LV diastolic dysfunction grade II and III, significant valve disease, or coronary artery disease with systolic LV dysfunction or dilatation. Associations between quantitative variables were analyzed by Pearson and Spearman correlation coefficients, and comparisons of quantitative data by Student's t-test for independent samples. Results: Increasing age was associated with a progressive decrease in the distance covered (p = 0.021), in the expected increase in HR (p < 0.001), in VO2 max (p < 0.001), and METs (p < 0.001) in both genders. There was no correlation of exercise test parameters with the echocardiographic parameters. Conclusions: Relatively healthy older individuals, with global systolic and diastolic functions of the left ventricle preserved, presented a progressive decrease in their functional capacity due to their natural aging process, comorbidities related to their age range and physical deconditioning.

摘要

背景：健康个体的最大摄氧量（VO2 max）每十年约下降10%，且70岁以后这种下降趋势更为显著。

目的：通过代谢当量（MET）与最大摄氧量测量，评估75岁及以上接受运动负荷试验与经胸超声心动图检查个体的功能能力。

方法：共纳入381例受试者（女性205例；年龄79±3.7岁）进行评估。排除标准包括：左心室（LV）收缩功能障碍、Ⅱ级及Ⅲ级左心室舒张功能障碍、显著瓣膜病变，或合并左心室收缩功能障碍或扩张的冠状动脉疾病。定量变量间的关联采用Pearson相关系数与Spearman相关系数分析，定量数据的组间比较采用独立样本Student t检验。

结果：在两性群体中，年龄增长均与运动完成距离、预期心率增幅（p<0.001）、最大摄氧量（p<0.001）及代谢当量（p<0.001）的进行性下降相关（p=0.021）。运动试验参数与超声心动图参数未发现显著相关性。

结论：左心室整体收缩与舒张功能保留的相对健康老年个体，其功能能力会因自然衰老过程、年龄相关合并症及身体失健状况而出现进行性下降。