Health Status after Invasive or Conservative Care in Coronary and Advanced Kidney Disease

Abstract

Background: In the ISCHEMIA-CKD trial, the primary analysis showed no significant difference in the risk of death or myocardial infarction with initial angiography and revascularization plus guideline-based medical therapy (invasive strategy) as compared with guideline-based medical therapy alone (conservative strategy) in participants with stable ischemic heart disease, moderate or severe ischemia, and advanced chronic kidney disease (an estimated glomerular filtration rate of <30 ml per minute per 1.73 m² or receipt of dialysis). A secondary objective of the trial was to assess angina-related health status.

Methods: We assessed health status with the Seattle Angina Questionnaire (SAQ) before randomization and at 1.5, 3, and 6 months and every 6 months thereafter. The primary outcome of this analysis was the SAQ Summary score (ranging from 0 to 100, with higher scores indicating less frequent angina and better function and quality of life). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate the treatment effect with the invasive strategy.

Results: Health status was assessed in 705 of 777 participants. Nearly half the participants (49%) had had no angina during the month before randomization. At 3 months, the estimated mean difference between the invasive-strategy group and the conservative-strategy group in the SAQ Summary score was 2.1 points (95% credible interval, -0.4 to 4.6), a result that favored the invasive strategy. The mean difference in score at 3 months was largest among participants with daily or weekly angina at baseline (10.1 points; 95% credible interval, 0.0 to 19.9), smaller among those with monthly angina at baseline (2.2 points; 95% credible interval, -2.0 to 6.2), and nearly absent among those without angina at baseline (0.6 points; 95% credible interval, -1.9 to 3.3). By 6 months, the between-group difference in the overall trial population was attenuated (0.5 points; 95% credible interval, -2.2 to 3.4).

Conclusions: Participants with stable ischemic heart disease, moderate or severe ischemia, and advanced chronic kidney disease did not have substantial or sustained benefits with regard to angina-related health status with an initially invasive strategy as compared with a conservative strategy. (Funded by the National Heart, Lung, and Blood Institute; ISCHEMIA-CKD ClinicalTrials.gov number, NCT01985360.).

Figure 1.. Unadjusted Mean Health-Status Scores Over Time.

Shown are mean health-status scores among participants who were randomly assigned to undergo initial coronary angiography and revascularization plus receive guideline-based medical therapy (invasive strategy) or to receive guideline-based medical therapy alone (conservative strategy). Shading represents the 95% confidence interval. On the Seattle Angina Questionnaire (SAQ), the Summary score (Panel A) is an average of the Angina Frequency, Quality of Life, and Physical Limitation scores (Panels B, C, and D, respectively); SAQ scores range from 0 to 100, with higher scores indicating better health status. On the Rose Dyspnea Scale (Panel E), scores range from 0 to 4, with higher scores indicating shortness of breath with milder activities. On the European Quality of Life–5 Dimensions (EQ-5D) visual analogue scale (Panel F), scores range from 0 to 100, with higher scores indicating better health status.

Figure 2.. Distributions of Differences between Treatment Groups in SAQ Summary Scores.

Shown are posterior distributions of estimated mean differences between the invasive-strategy group and the conservative-strategy group in the SAQ Summary score, according to angina frequency at baseline (as assessed with the SAQ Angina Frequency score) and time point. Positive numbers on the x axis show the magnitude of benefits with an invasive strategy, and the y axis shows the probability of those benefits.