Simple pre-procedure risk stratification tool for contrast-induced nephropathy

Abstract

Background: A few simple and pre-procedural risk models have been developed for predicting contrast-induced nephropathy (CIN), which allow for early administration of preventative strategies before coronary angiography (CAG). The study aims to develop and validate simple pre-procedure tools for predicting risk of CIN following CAG.

Methods: We retrospectively analyzed the data from 3,469 consecutive patients undergoing CAG, who were randomly assigned to a development dataset (n=2,313) and a validation dataset (n=1,156). CIN was defined as an increase in serum creatinine (SCr) ≥0.5 mg/dL from baseline within 72 hours after CAG. Multivariate logistic regression was applied to identify independent predictors of CIN to develop risk models. The possible predictors included age >75 years, hypotension, acute myocardial infarction (AMI), SCr ≥1.5 mg/dL, and congestive heart failure (CHF).

Results: The incidences of CIN were 3.20% and 3.55% in the training and validation dataset respectively. Compared to classical Mehran' and ACEF CIN risk score, the new score across the validation dataset exhibited similar discrimination and predictive ability on CIN (c-statistic: 0.829, 0.832, 0.812 respectively) and in-hospital mortality (c-statistic: 0.909, 0.937, 0.866 respectively) (all P>0.05).

Conclusions: The easy-to-use pre-procedural prediction model only containing 5 factors had similar predictive ability on CIN and mortality.

Keywords: Contrast-induced nephropathy (CIN); coronary angiography (CAG); percutaneous coronary intervention; risk score.

Figure 1

Incidence of contrast induced nephropathy according to the risk score. Increasing risk of CIN with increasing risk score is evident, Cochran Armitage chi-square, P<0.001. CIN, contrast-induced nephropathy.

Figure 2

Incidence of contrast induced nephropathy in the development and validation datasets according to risk strata.

Figure 3

Comparison of predictive accuracy of CIN risk score models between Chen score, Mehran score and ACEF score in CIN_0.5 (validation dataset). CIN, contrast-induced nephropathy.

Figure 4

Risk score and short-and long-term outcomes. Rates of in-hospital death and MACEs, 2- and 3-year all-cause mortality and MACEs, in the low-, moderate-, and high-risk groups were showed according to the Chen, Mehran, ACEF risk scores. MACE, major adverse clinical event.

Figure 5

Predictive ability of the risk scores for in-hospital death and MACEs, 2- and 3-year all-cause mortality and MACEs by Chen, Mehran, ACEF risk scores. MACE, major adverse clinical event.

Figure 6

Discrimination (c-statistic) and calibration (HosmereLemeshow test) for Chen score, Mehran score and ACEF score. a = Chen score; b = Mehran score; c = ACEF score.

Figure 7

Cumulative mortality as a function of time for patients with low, medium, and high present risk score. Chi-square =89.229, P<0.001.