摘要
There is limited evidence regarding the prognostic value of the 6-minute walk test for patients with advanced heart failure (HF). Accordingly, we studied 260 patients presenting to inpatient cardiac rehabilitation (CR) with advanced HF. The primary outcome was 3-year all-cause mortality after discharge from CR. The association between 6-minute walk distance (6MWD) and the primary outcome was determined using the multivariable Cox regression analysis. To avoid collinearity, 6MWD at admission (6MWDadm) to CR and 6MWD at discharge (6MWDdisch) from CR were analyzed separately. At multivariable analysis, 4 baseline characteristics (age, ejection fraction, systolic blood pressure, and blood urea nitrogen) were identified as prognostic of the primary outcome (baseline risk model). After adjusting for the baseline risk model, the hazard ratios of 6MWDadm and 6MWDdisch modeled as per 50-m increase for the primary outcome were 0.92 (95% confidence interval [CI] 0.85 to 0.99, p = 0.035) and 0.93 (95% CI 0.88 to 0.99, p = −017), respectively. After adjusting for the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) score, the corresponding hazard ratios were 0.91 (95% CI 0.84 to 0.98, p = 0.017) and 0.93 (95% CI 0.88 to 0.99, p = 0.016). The addition of either 6MWDadm or 6MWDdisch to the baseline risk model or the MAGGIC score yielded a statistically significant increase in global chi-square and in the net proportion of survivors reclassified downward. In conclusion, our data suggest that the distance covered during a 6-minute walk test predicts survival and provides incremental prognostic information on the top of well-established prognostic factors and the MAGGIC risk score in advanced HF. There is limited evidence regarding the prognostic value of the 6-minute walk test for patients with advanced heart failure (HF). Accordingly, we studied 260 patients presenting to inpatient cardiac rehabilitation (CR) with advanced HF. The primary outcome was 3-year all-cause mortality after discharge from CR. The association between 6-minute walk distance (6MWD) and the primary outcome was determined using the multivariable Cox regression analysis. To avoid collinearity, 6MWD at admission (6MWDadm) to CR and 6MWD at discharge (6MWDdisch) from CR were analyzed separately. At multivariable analysis, 4 baseline characteristics (age, ejection fraction, systolic blood pressure, and blood urea nitrogen) were identified as prognostic of the primary outcome (baseline risk model). After adjusting for the baseline risk model, the hazard ratios of 6MWDadm and 6MWDdisch modeled as per 50-m increase for the primary outcome were 0.92 (95% confidence interval [CI] 0.85 to 0.99, p = 0.035) and 0.93 (95% CI 0.88 to 0.99, p = −017), respectively. After adjusting for the Meta-analysis Global Group in Chronic Heart Failure (MAGGIC) score, the corresponding hazard ratios were 0.91 (95% CI 0.84 to 0.98, p = 0.017) and 0.93 (95% CI 0.88 to 0.99, p = 0.016). The addition of either 6MWDadm or 6MWDdisch to the baseline risk model or the MAGGIC score yielded a statistically significant increase in global chi-square and in the net proportion of survivors reclassified downward. In conclusion, our data suggest that the distance covered during a 6-minute walk test predicts survival and provides incremental prognostic information on the top of well-established prognostic factors and the MAGGIC risk score in advanced HF. Should the Six-Minute Walk Test Be Added to the Vital Signs? Why Is Walking so Beneficial? Obesity Paradox?American Journal of CardiologyVol. 201PreviewVital signs have evolved slowly over the last century. Paul Dudley White aided the introduction of blood pressure during recruitment for World War I soldiers. At the time, the danger of hypertension was not known, and elevated blood pressure was labeled as essential. The most recent vital sign addition was oxygen saturation when technology made it affordable. Height, weight, calculated body mass index, pulse rate, temperature, and oxygen saturation are now recorded for every patient visit, and each has prognostic value. Full-Text PDF