Invasive management of acute coronary syndrome: Interaction with competing risks

• Published in: International journal of cardiology 2018-10, Vol.269, p.13-18
• Main Authors: Chuang, Anthony (Ming-yu), Hancock, David G., Halabi, Amera, Horsfall, Matthew, Vaile, Julian, De Pasquale, Carmine, Sinhal, Ajay, Jones, Dylan, Brogan, Richard, Chew, Derek P.
• Format: Article
• Language: English
• Subjects: Acute Coronary Syndrome - diagnosis; Acute Coronary Syndrome - mortality; Acute Coronary Syndrome - surgery; Acute coronary syndromes; Aged; Aged, 80 and over; Disease Management; Female; Flexible parametric; Follow-Up Studies; Humans; Male; Middle Aged; Mortality - trends; Percutaneous coronary intervention; Percutaneous Coronary Intervention - methods; Percutaneous Coronary Intervention - trends; Propensity score; Prospective Studies; Registries; Risk Factors
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/j.ijcard.2018.07.078

The aim of this study was to characterise the interaction between ACS- and non-ACS-risk on the benefits of invasive management in patients presenting with acute coronary syndrome (ACS). Consecutive patients admitted to a tertiary hospital's Cardiac Care Unit in the months of July–December, 2003–2011 with troponin elevation (>30 ng/L) were included. “ACS-specific-risk” was estimated using the GRACE score and “non-ACS-risk” was estimated using the Charlson-Comorbidity-Index (CCI). Inverse-probability-of-treatment weighting was used to adjust for baseline differences between patients who did or did not receive invasive management. A multivariable flexible parametric model was used to characterise the time-varying hazard. In total, 3057 patients were included with a median follow-up of 9.0 years. Based on CCI, 1783 patients were classified as ‘low-non-ACS risk’ (CCI ≤ 1; invasive management 81%; 12-month mortality 5%), 820 as ‘medium-non-ACS risk’ (CCI 2–3; invasive management 68%; 12-month mortality 13%), and 468 as ‘high-non-ACS risk’ (CCI ≥ 4; invasive management 47%; 12-month mortality 29%). After adjustment, invasive management was associated with a significant reduction in one-year overall-mortality in the ‘low-risk’ and ‘medium-risk’ groups (HR = 0.38, 95%CI:0.26–0.56; HR = 0.46, 95%CI:0.32–0.67); but not in the ‘high-risk’ group (HR = 1.02, 95%CI:0.67–1.56). The absolute benefit of invasive management was greatest with higher baseline ACS-risk, with a non-linear interaction between ACS- and non-ACS-risk. There is a complex interaction between ACS- and non-ACS-risk on the benefit of invasive management. These results highlight the need to develop robust methods to objectively quantify risk attributable to non-ACS comorbidities in order to make informed decisions regarding the use of invasive management in individuals with numerous comorbidities. •Benefits of invasive management for ACS not clear if significant comorbidities•ACS risk and non-ACS risk on benefits of invasive management evaluated•Invasive management beneficial if low and medium non-ACS risk, but not if high•Benefit diminished over time and modified by non-linear interaction with ACS risk•Tools to robustly model non-ACS risk to guide treatment decision needed