Incidence of Contrast Induced Nephropathy Among Different Stroke Subtypes After Adoption of New Emergency Brain Imaging Protocol for Acute Stroke - A Single Center Perspective.

Introduction: Studies demonstrating benefits of mechanical thrombectomy for large vessel occlusion (LVO) in acute ischemic stroke (AIS) has led to increased use of CT angiogram (CTA). Similarly, CTA is frequently performed to diagnose cerebrovascular pathology after intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH). Such contrast-enhanced CT (CECT) studies in stroke population are often associated with contrast induced nephropathy (CIN). However, incidence of CIN after adoption of increased use of CTA to diagnose LVO for possible mechanical thrombectomy is largely unknown. Hypothesis: We investigated the incidence of CIN in acute stroke population after adoption of CECT protocol to diagnose LVO and compared it to patients undergoing CECT study for other indications. Methods: Single-center retrospective chart review of patients presenting to the emergency room and investigated with CECT between January 2015 and December 2017. A rise in serum creatinine (SCr) 1.5 times the presenting SCr within first 72 hours of CECT defined CIN. Non-parametric Chi-squared tests were used to make intergroup comparison and a p-value of <0.05 was considered significant. Results: Nine hundred and forty-seven charts of patients undergoing CECT were reviewed. Patients with ICH [30/132 (22.7%)] and SAH [17/126 (13.5%)] had significantly higher incidence of CIN as compared to those with AIS [11/150 (7.3%)] and non-stroke [36/494 (6.8%)] etiologies. Patients developing CIN had increased length of stay in all groups with it being statistically significant in non-stroke (p<0.0001) and ICH (p<0.004). Diabetes mellitus was identified as a significant risk factor for CIN in AIS (p=0.0094) and non-stroke population (p=0.0002). Use of antihypertensives during the first 72 hours of admission was significantly associated with CIN (p=0.0025) among non-stroke patients whereas it was not identified to be a risk factor for CIN in stroke cohort. Intravenous hydration was not associated with prevention of CIN in any of the study groups. Conclusion: Our study results demonstrate higher incidence of CIN among patients with hemorrhagic stroke and reports risk for developing CIN in AIS is comparable to non-stroke population undergoing CECT in emergency circumstances.