Balashov Konstantin, Feldman Debbie Ehrmann, Savard Sylvie, Houde Stéfanie, Frenette Marc, Ducharme Anique, Giannetti Nadia, Michel Caroline, Pilote Louise
University of Montreal, School of Rehabilitation, Montreal, Canada.
J Card Fail. 2008 Feb;14(1):75-81. doi: 10.1016/j.cardfail.2007.09.005.
The 6-minute walk test (6MWT) is a widely used measure of functional capacity in patients with chronic heart failure (CHF). Norm-referenced equations that predict the 6-minute walk distance (6MWD) according to age, height, weight, and gender have been proposed for healthy patients. We explored whether these equations apply to CHF patients.
The sample consisted of 213 patients newly admitted to specialized CHF clinics in Montreal, Canada. Percent predicted value (PPV) for 6MWD was calculated using norm-referenced equations. We explored correlations between different measures: PPV, 6MWD, Minnesota Living with Heart Failure Quality of Life score (MLHF-QOL). We compared severity among different age, gender, and BMI (body mass index) subgroups and assessed consistency using different measures of severity. Mean age was 65.5 years and 77.5% were men. Compared with the 6MWD, PPV had a slightly better correlation with MLHF-QOL score (-0.26 versus -0.20), and slightly more predictive power in linear regressions (adjusted r(2) = 6.5% versus 4.2%). When PPV was used to differentiate severity between different age, gender, and BMI subgroups, it consistently led to similar conclusions as the MLHF-QOL score, unlike 6MWD.
The 6MWD in meters may give misleading results when used as an indicator of severity of CHF condition to compare groups with different sex, age, and BMI distributions. It may be necessary to standardize it using norm-referenced equations.
6分钟步行试验（6MWT）是慢性心力衰竭（CHF）患者功能能力的一种广泛使用的测量方法。已针对健康患者提出了根据年龄、身高、体重和性别预测6分钟步行距离（6MWD）的常模参照方程。我们探讨了这些方程是否适用于CHF患者。
样本包括213名新入住加拿大蒙特利尔专门CHF诊所的患者。使用常模参照方程计算6MWD的预测值百分比（PPV）。我们探讨了不同测量值之间的相关性：PPV、6MWD、明尼苏达心力衰竭生活质量评分（MLHF-QOL）。我们比较了不同年龄、性别和BMI（体重指数）亚组之间的严重程度，并使用不同的严重程度测量方法评估一致性。平均年龄为65.5岁，77.5%为男性。与6MWD相比，PPV与MLHF-QOL评分的相关性略好（-0.26对-0.20），并且在线性回归中的预测能力略强（调整后的r² = 6.5%对4.2%）。当使用PPV区分不同年龄、性别和BMI亚组之间的严重程度时，与MLHF-QOL评分一致，它始终得出相似的结论，这与6MWD不同。
当将以米为单位的6MWD用作比较具有不同性别、年龄和BMI分布的组的CHF病情严重程度指标时，可能会产生误导性结果。可能有必要使用常模参照方程对其进行标准化。
