Abstract W P332: Ratio of Blood Urea Nitrogen to Serum Creatinine Predicts Primary Intracerebral Hemorrhage Volume

Abstract

Background&Purpose: Dehydration is associated with poor outcomes in stroke patients. A common marker of hydration status is the calculated blood urea nitrogen (BUN) to serum creatinine (SCr) ratio. Few studies in primary ICH patients have focused on intravascular volume depletion and ICH volume. We examined if dehydration (BUN/SCr > 15) predicted admission ICH volume. Subjects&Methods: Consecutive patients (2008 – 2013) who presented with a spontaneous ICH to our academic stroke center in the Southeast US were retrospectively analyzed. Demographics, initial lab values, ICH volumes, and ICH scores were recorded. Patients with INR <= 1.5 were divided into two groups: BUN/SCr <= 15 and > 15. ICH volumes were compared between groups. Statistical significance was determined using linear regression adjusting for admission systolic blood pressure (SBP) and ICH score. Results: We identified 326 patients who met inclusion criteria (mean age 63; SD=15, 43% women, 45% black). Patients with ratio >15 were older (68 vs.60 years, p<0.001). In addition, a higher proportion were white (63% vs.40%, p <0.001) and female (56% vs. 36%, p<0.001). The average SBP on arrival was similar between groups (176 vs.181 mmHg, p=0.159). The average initial ICH volumes for those with BUN/SCr > 15 were higher than patients with BUN/SCr <= 15 (29.6 mL vs. 20.6 mL, p = 0.022). After adjusting for SBP and ICH score, patients with elevated BUN/SCr had an average of 9 mL larger ICH volumes on admission. Conclusions: Elevated BUN/SCr ratio is linked to larger initial ICH volumes even after controlling for ICH score and SBP. This simple ratio is an independent predictor of ICH volume, may reflect poor hydration status, and can potentially be used in the early evaluation and treatment of ICH patients. Future studies to determine if correction impacts functional outcomes are warranted.