Lymphopenia, Infectious Complications, and Outcome in Spontaneous Intracerebral Hemorrhage

Lymphopenia is increasingly recognized as a consequence of acute illness and may predispose to infections. We investigated whether admission lymphopenia (AL) is associated with increased risk of infectious complications and poor outcome in patients with spontaneous intracerebral hemorrhage (ICH). We retrospectively analyzed a prospectively collected cohort of ICH patients ascertained between 1994 and 2015. We identified subjects with lymphocyte count obtained within 24 h from onset, and AL was defined as lymphocyte count < 1000/mu L. Infectious complications were assessed through retrospective chart review. Association between AL, infections, and mortality was investigated using multivariable logistic regression. Of the 2014 patients meeting inclusion criteria, 548 (27.2%) had AL and 605 (30.0%) developed an infectious complication. Case-fatality at 90 days was 36.9%. Patients with AL had larger hematoma volumes, higher frequency of intraventricular hemorrhage, and lower Glasgow Coma Scale score on presentation (all p < 0.001). AL was independently associated with increased risk of pneumonia [odds ratio (OR) 1.97, 95% confidence interval (CI) 1.50-2.58, p < 0.001] and multiple infections (OR 1.84, 95% CI 1.24-2.71, p = 0.003). AL was also an independent predictor of 90-day mortality (OR 1.55, 95% CI 1.18-2.04, p = 0.002) after adjusting for confounders. AL is common in ICH patients and independently associated with increased risk of infectious complications and poor outcome. Further studies will be needed to determine whether prophylactic antibiotics in ICH patients with AL can improve outcome.