Abstract 1055: Physical Limitation Risk Score and Cardiovascular History Predict Death and MI in the COURAGE Trial
Background: Physical limitation (PL) has been associated with greater risk of cardiovascular events in stable coronary artery disease patients. This study developed a risk score for physical limitation and assessed its long-term prognostic value in COURAGE trial patients.
Method: Physical limitation was assessed by the Seattle Angina Questionnaire. Lower scores are associated with greater PL. Data were collected at baseline, 1, 3, 6 and 12 months and annually thereafter. A tree-based classification model was performed to search for a cut point for risk. Event rates (death or non-fatal MI) were analyzed by Cox proportional hazards regression.
Results: A PL score <45 was the optimal cut point established by baseline data. Nearly 25% of patients had PL scores <45. There was a statistically significant greater event rate in patients with PL score <45 at baseline compared with those with the score ≥45 (hazard ratio=1.97, P<0.001). At-risk patients at baseline and month 3 were 3.02 times more likely to experience an event than patients not at risk. However, patients not at risk were 1.67 times (P=0.02) more likely to suffer an event if their PL score declined more than 20 points from month 1 to 3. There was a significantly greater event rate in patients with one of previous CHF, CABG or PCI history plus PL risk than patients with the previous history but no PL risk, and patients with neither (Figure⇓).
Conclusions: Based on PL risk, serial measures of PL used to identify patients with persistent poor PL, or marked declines of PL score, combined with previous cardiovascular disease history, can improve prediction for the primary outcome in patients with stable coronary artery disease.