Persistent cognitive impairment, hippocampal atrophy and EEG changes in sepsis survivors
- Alexander Semmler1,6,
- Catherine Nichols Widmann1,
- Thorsten Okulla1,
- Horst Urbach2,
- Markus Kaiser3,7,
- Guido Widman4,
- Florian Mormann4,8,
- Julia Weide1,
- Klaus Fliessbach4,
- Andreas Hoeft3,
- Frank Jessen5,
- Christian Putensen3,
- Michael T Heneka1
- 1Department of Neurology, University of Bonn, Bonn, Germany
- 2Department of Radiology/Neuroradiology, University of Bonn, Bonn, Germany
- 3Department of Anaesthesiology and Intensive Care Medicine, University of Bonn, Bonn, Germany
- 4Department of Epileptology, University of Bonn, Bonn, Germany
- 5Department of Psychiatry, University of Bonn, Bonn, Germany
- 6Department of Neurology, University of Zurich, Zurich, Switzerland
- 7Department of Anaesthesiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- 8Division of Biology, California Institute of Technology, USA
- Correspondence to Professor Michael T Heneka, Department of Neurology, University of Bonn, Clinical Neurosciences, Sigmund-Freud Street 25, Bonn 53127, Germany;
- Received 24 April 2012
- Revised 24 August 2012
- Accepted 28 August 2012
- Published Online First 7 November 2012
Objectives The objective of this preliminary study was to explore long-term changes in neurobehavioral parameters, brain morphology and electroencephalography of sepsis patients who received intensive care compared to non-septic intensive care unit (ICU) patients.
Methods Two-centre follow-up study 6–24 months after discharge from hospital using published norms and existing databases of healthy controls for comparison. Patients included 25 septic and 19 non-septic ICU survivors who were recruited from two ICUs of a university and community hospital. Measurements used include brain morphology, standard electroencephalography, cognition and psychiatric health and health-related quality of life.
Results Sepsis survivors showed cognitive deficits in verbal learning and memory and had a significant reduction of left hippocampal volume compared to healthy controls. Moreover, sepsis and to some extent non-septic ICU patients had more low-frequency activity in the EEG indicating unspecific brain dysfunction. No differences were found in health-related quality of life, psychological functioning or depressive symptoms, and depression could be ruled out as a confounding factor.
Conclusions This study demonstrates permanent cognitive impairment in several domains in both septic and non-septic ICU survivors and unspecific brain dysfunction. In the sepsis group, left-sided hippocampal atrophy was found compared to healthy controls. Further study is needed to clarify what contribution sepsis and other factors at the ICU make to these outcomes. Specific neuroprotective therapies are warranted to prevent persisting brain changes in ICU patients.