Comparing Days Alive and Out of Hospital with Invasive vs Conservative Management in ISCHEMIA

A prespecified analysis of the ISCHEMIA trial has returned mixed results related to the impact of initial management strategy on days alive and out of the hospital in patients with stable ischemic heart disease (SIHD).

Results of the analysis suggest use of a conservative strategy resulted in greater days alive out of hospital at 1 month, 1 year, and 2 years, but investigators highlighted there was no difference was observed between the study arms at 4 years of follow-up and the early differences were mostly driven by protocol-assigned stays mandated within the invasive management approach.

“This analysis of DAOH in the ISCHEMIA trial showed that randomization to the conservative management group compared with the invasive management group was associated with significantly more DAOH during the first 2 years, with no significant difference beyond 2 years. The differences were small and no greater than 6.3 days at any analyzed time point,” wrote investigators.

With an interest in exploring the risks and benefits of initial invasive versus conservative management in patients with SIHD beyond traditional trial end points, ISCHEMIA investigators designed the current prespecified analysis to compare days alive out of hospital according to initial management strategy among patients within the landmark trial. Briefly, the ISCHEMIA trial was originally presented at AHA 2019 and concluded that an early invasive approach reduced angina among these patients but provided no overall benefit compared to conservative management.

For the current analysis, investigators hoped to compare days alive and out of hospital, including invasive protocol-assigned stays, at 1 month, 1 year, 2 years, and 4 years after randomization. For the purpose of analysis, stays included overnight stays in hospital or extended care facilities, such as a skilled nursing facility, rehabilitation, or a nursing home.

From the 5179 patients included in the analysis, investigators identified 5899 stays. Of the 5899 stays included in the analysis, 4002 occurred in the invasive management group and 1897 occurred in the conservative management group.

At 1 month, estimated cumulative mean days alive out of hospital was 2.4 days greater among those in the conservative group compared to those randomized to invasive management (30.8 vs 28.4; difference: 2.4; 95% CI, 2.2-2.6; P <.001). At 1 year, the mean additional days alive out of hospital for the conservative management group was 6.3 days greater than those randomized to invasive management (362.2 vs 355.9; difference: 6.3; 95% CI, 4.8-7.7; P <.001). At 2 years, the mean additional days alive out of hospital was 6.3 days greater among patients randomized to initial conservative management than invasive management (718.4 vs 712.1; difference, 6.3; 95% CI, 2.4-10.2; P=.001).

At 4 years, there was no significant difference in mean days alive out of hospital with 1412.2 and 1415.0 among patients randomized to invasive management and conservative management, respectively (P=.001). Further analysis indicated 2434 of 4002 stays among the invasive management group were protocol-assigned procedures. When excluding these stays, investigators were unable to identify clear differences at any time point based on management group.

Additionally, after exclusion of these stays, there were fewer stays among those randomized to an invasive approach (n=1568) than among those randomized to a conservative approach (n=1897; P=.001). When assessing cardiovascular says followed initial assigned procedures, investigators found a lower number of stays among those randomized to invasive rather than conservative management (685 of 4002 [17.1%] vs 1095 of 1897 [57.8%]; P >.001) and this was driven by decreased spontaneous myocardial infarction stays (65 [1.6%] vs 123 [6.5%]; P <.001) and unstable angina stays (119 [3.0%] vs 216 [11.4%]; P <.001).

“DAOH provides a patient-focused metric that can be used by clinicians and patients in shared decision-making for the management of stable coronary artery disease,” wrote investigators.

This study, "Comparison of Days Alive Out of Hospital With Initial Invasive vs Conservative Management,” was published in JAMA Cardiology.