Objective: To investigate the incidence of coutrast media iodixanol-induced delayed adverse reaction with the risk factors in general clinical practice.
Methods: A total of 20,185 patients with contrast iodixanol were recruited from 95 medical centers in China. The risk factors for adverse drug reaction as hypertension, asthma, previous contrast reaction were assessed;the administrative processes as route, injection manner, lfow rate of injection, prior heating of iodixanol were monitored and the demographic information was documented. The immediate adverse reaction within 1 hour of media administration and the delayed adverse reaction from 1 hour to 7 days after administration were recorded. The risk factors for iodixanol-induced delayed adverse reaction were studied by singlevariate and multivariate logistic regression analysis.
Results: The overall iodixanol-induced adverse reaction rate was 1.52%, of which the immediate reaction was 0.58%and delayed reaction was 0.97%. The major delayed reaction was mild and it mostly happened in skin (0.68%) including rash, pruritus and urticaria. Multivariate logistic regression analysis revealed that male gender (OR=0.71, P=0.036), age (OR=0.82, P=0.001), route of administration (OR=0.21, P<0.001), prior heating of iodixanol (OR=1.44, P=0.036), lfow rate of injection (OR=1.28, P=0.001) and previous contrast reaction (OR=16.04, P<0.001) were the independent risk factors for delayed adverse reactions.

Acute coronary syndrome is a group of clinical syndromes based on the pathological basis of complete or incomplete occlusion of coronary artery caused by the rupture or invasion of coronary atherosclerotic plaque. It is a serious type of coronary heart disease. Acute coronary syndrome is clinically characterized by an acute onset of action and rapid pathological changes. Its prognosis differs greatly among patients with different categories of acute coronary syndrome and patients with the same category of acute coronary syndrome. Therefore, it is particularly important to reasonably use the risk score for risk stratification in patients with acute coronary syndrome, and select the optimized clinical treatment strategy according to the risk stratification, so as to reduce complications, reduce mortality and improve prognosis. This paper reviews the application of risk score in acute coronary syndrome.