Aims: Several treadmill exercise testing prognostic parameters have been identified in various populations. However, despite the widespread use of treadmill exercise testing, the prognostic value in very elderly patients has not been well characterized. The aim of this study was to assess the results of treadmill exercise testing in octogenarians, and to examine various parameters in order to identify a prognostic marker of mortality.
Methods and results: This study included 97 consecutive octogenarians (age, 81.1 ± 1.8 years; 66% male) who were referred for treadmill exercise testing. During the follow-up period (2.6 ± 1.6 years), all-cause death occurred in 20 patients (21%). Univariate Cox proportional hazard regression analysis showed that abnormal heart rate recovery (HRR) (defined as a decreased heart rate of ≤ 18 beats per minute after peak exercise) [hazard ratio (HR), 2.82; 95% confidence interval (CI), 1.06-7.47; P = 0.037] and ischaemic ST-segment change (HR, 2.56; 95% CI, 1.01-6.46; P = 0.047) were significantly associated with all-cause mortality. After adjusting for age and sex, multivariate Cox proportional hazard analysis showed that abnormal HRR was the only independent predictor of all-cause death (HR, 2.86; 95% CI, 1.01-8.11; P = 0.048).
Conclusion: Attenuated HRR is a significant prognostic marker for all-cause death among octogenarians. The results may provide helpful support for risk stratification in clinical practice.