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Published on: October 15, 2021
Lymphopenia, Infectious Complications, and Outcome in Spontaneous Intracerebral Hemorrhage
Andrea Morotti1,2, Sandro Marini3,4, Michael J Jessel4
1Division of Neurocritical Care and Emergency Neurology, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. amorotti@mgh.harvard.edu.
Insights
Admission lymphopenia (AL) in patients with intracerebral hemorrhage (ICH) is common and linked to a higher risk of infections and mortality. This finding highlights the importance of monitoring lymphocyte counts in ICH patients for better outcomes.
Area of Science:
- Neurology
- Infectious Diseases
- Critical Care Medicine
Background:
- Lymphopenia, a low lymphocyte count, is a recognized complication of acute illness.
- Its role in spontaneous intracerebral hemorrhage (ICH) and subsequent complications requires further investigation.
Purpose of the Study:
- To determine if admission lymphopenia (AL) is associated with an increased risk of infectious complications.
- To assess the impact of AL on patient outcomes, including mortality, in spontaneous ICH.
Main Methods:
- Retrospective analysis of a prospectively collected cohort of 2014 ICH patients (1994-2015).
- AL defined as lymphocyte count <1000/μL within 24 hours of onset.
- Infectious complications assessed via chart review; outcomes analyzed using multivariable logistic regression.
Main Results:
- 27.2% of ICH patients had AL; 30.0% developed infections.
- AL was independently associated with higher risks of pneumonia (OR 1.97) and multiple infections (OR 1.84).
- AL independently predicted increased 90-day mortality (OR 1.55) and was linked to larger hematoma volumes and lower GCS scores.
Conclusions:
- Admission lymphopenia is prevalent in ICH patients.
- AL is an independent predictor of infectious complications and poor 90-day outcomes.
- Further research is needed to explore prophylactic antibiotic strategies for ICH patients with AL.
Background:
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).
Methods:
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/μL. Infectious complications were assessed through retrospective chart review. Association between AL, infections, and mortality was investigated using multivariable logistic regression.
Results:
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.
Conclusions:
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.
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