Risk Factors And Prediction Models For Contrast-induced Nephropathy Following Coronary Angiography

Contrast-induced nephropathy(CIN)is one of the most common complications following cardiac catherization,and is associated with worse prognosis.At present,there are multiple definitions of CIN,which has led to different reports on its incidence and prognosis.Moreover,the mechanism of CIN occurrence is still unclear.Therefore,it is critical to establish simple and reliable prediction models for high-risk patients to assess their risk in time.Objectives and significance:1.Through comparing the population attributable risks(PARs)of 4 commonly used CIN definitions,this study aimed to identify the most relevant definition of CIN regarding long-term prognosis and its independent risk factors.And by estimating the PARs of each risk factor,this study aimed to find out the most valuable intervention targets.2.To form a novel prediction model by analyzing high-risk CIN populations(patients with congestive heart failure/chronic kidney disease).Methods:Patients:3450 consecutive patients undergoing coronary angiography(CAG)or percutaneous coronary intervention(PCI)in Guangdong Provincial People’s Hospital.Endpoints:Primary endpoint:CIN,defined as the 4 following definitions:(1)CINa:defined as serum creatinine elevation≥0.3 mg/dL or 50%from baseline within the first 72 hours following the procedure;(2)CINb:≥0.5 mg/dL from baseline;(3)CINc:≥25%from baseline;(4)CINd:≥0.5 mg/dL or 25%from baseline;Secondary endpoints:all-cause deathStatistical analysis:Continuous variables were compared with an unpaired,2-tailed t test or Wilcoxon rank-sum test;Categorical variables were compared using theχ2 test or Fisher’s exact test;Univariable and multivariable COX regression analysis was used to evaluate the relationship between CIN and long-term prognosis and calculate hazard ratio(HR);Univariable and multivariable logistic regression were used to assess the relationship between risk factors and CIN and calculate the odds ratio(OR);PARs were calculated with their HR/OR and prevalence.Results:Finally,3450 patients were included in the analysis.In general,the average age was 62.94±11.13 years.There were 643(18.64%)patients complicated with chronic kidney disease,while 1876(54.85%)patients complicated with congestive heart failure.Overall,the incidence was 248(7.19%)for CINa,113(3.28%)for CINb,415(12.03%)for CINc,and 421(12.20%)for CINd.Regardless of the definition,patients with CIN demonstrated a worse long-term prognosis.In particular,among the four CIN definitions,CINa had the highest PAR(4.92%)and CINc had the lowest(3.71%).Among the independent risk factors for CINa,4 risk factors(congestive heart failure,hypoproteinemia,high contrast volume and hypotension)were deem modifiable.Also,among the 4 modifiable risk factors,congestive heart failure had the highest PAR value(38.06%),and hypotension had the lowest(4.21%).For patients with chronic kidney disease,the nomogram including age,heart rate,estimate glomerular filtration rate,acute myocardial infarction,PCI and beta-blocker demonstrated a better predictive value than the classic Mehran Score(area under curve:0.76 vs 0.68,P=0.025).The simple nomogram including four predictors(age,intra-aortic balloon pump,acute myocardial infarction and chronic kidney disease)demonstrated a similar predictive power as the Mehran score(area under curve:0.80 vs 0.75,P=0.061).Conclusions:1.All the four commonly used definitions of CIN are related to the long-term prognosis of patients undergoing cardiac catheterization,among which CINa has the highest PAR(4.92%);2.4 modifiable CIN risk factors identified in this article may be important and cost-effective targets for CIN prevention;3.This study established two CIN prediction models based on chronic kidney disease and congestive heart failure patients respectively,which can effectively estimate the risk.