Temporal trends and inequalities in coronary angiography utilization in the management of non-ST-Elevation acute coronary syndromes in the U.S.

Coronary angiography (CA) is the basis of an invasive management strategy in non-ST elevation acute coronary syndromes (NSTEACS). There are limited contemporary data on national temporal trends in utilization of CA in different patient subgroups. We sought to investigate temporal trends, predictors and clinical outcomes associated with the use of CA in the US. Using the Nationwide Inpatient Sample (NIS) from 2004–2014, we identified all inpatient admissions, age ≥18, with a primary diagnosis of NSTEACS. Descriptive statistics and multivariable logistic regression models were used to investigate temporal trends, predictors and clinical outcomes associated with CA. From a total of 4,380,827 patients, 57.5% received CA during the study period and were more likely to be male, younger and less comorbid as defined per Charlson comorbidity index. The proportion of patients receiving CA increased from 48.5% to 68.5%, however, higher proportional increase was observed in males (53.9% to 69.4% P(trend) < 0.001) and those age ≤60 years (59.0% to 77.9% P(trend) < 0.001). Prior history of CABG (OR 0.33 95%CI 0.35–0.36), previous PCI (OR 0.84 95%CI 0.83–0.86) and previous AMI (OR 0.65 95%CI 0.64–0.67) were inversely related with receipt of CA. Receipt of CA was strongly associated with decreased odds of in-hospital mortality (OR 0.38 95%CI 0.36–0.40). In this national analysis, we observed a temporal increase in utilization of CA albeit slower adoption was noted in older, women and more comorbid patients. The risk-treatment paradox wherein patients who are most likely to benefit were less likely to receive CA persists even in contemporary practice.