title: Inflammation, negative nitrogen balance, and outcome after aneurysmal subarachnoid hemorrhage.
abstract: OBJECTIVE
  To analyze the impact of inflammation and negative nitrogen balance (NBAL) on nutritional status and outcomes after subarachnoid hemorrhage (SAH).
  
  
  METHODS
  This was a prospective observational study of SAH patients admitted between May 2008 and June 2012. Measurements of C-reactive protein (CRP), transthyretin (TTR), resting energy expenditure (REE), and NBAL (g/day) were performed over 4 preset time periods during the first 14 postbleed days (PBD) in addition to daily caloric intake. Factors associated with REE and NBAL were analyzed with multivariable linear regression. Hospital-acquired infections (HAI) were tracked daily for time-to-event analyses. Poor outcome at 3 months was defined as a modified Rankin Scale score ≥ 4 and assessed by multivariable logistic regression.
  
  
  RESULTS
  There were 229 patients with an average age of 55 ± 15 years. Higher REE was associated with younger age (p = 0.02), male sex (p < 0.001), higher Hunt Hess grade (p = 0.001), and higher modified Fisher score (p = 0.01). Negative NBAL was associated with lower caloric intake (p < 0.001), higher body mass index (p < 0.001), aneurysm clipping (p = 0.03), and higher CRP:TTR ratio (p = 0.03). HAIs developed in 53 (23%) patients on mean PBD 8 ± 3. Older age (p = 0.002), higher Hunt Hess (p < 0.001), lower caloric intake (p = 0.001), and negative NBAL (p = 0.04) predicted time to first HAI. Poor outcome at 3 months was associated with higher Hunt Hess grade (p < 0.001), older age (p < 0.001), negative NBAL (p = 0.01), HAI (p = 0.03), higher CRP:TTR ratio (p = 0.04), higher body mass index (p = 0.03), and delayed cerebral ischemia (p = 0.04).
  
  
  CONCLUSIONS
  Negative NBAL after SAH is influenced by inflammation and associated with an increased risk of HAI and poor outcome. Underfeeding and systemic inflammation are potential modifiable risk factors for negative NBAL and poor outcome after SAH.
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY. nbadjatia@som.umaryland.edu.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Badjatia
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Aimee
authors.initials: A
authors.lastname: Monahan
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Amanda
authors.initials: A
authors.lastname: Carpenter
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Zimmerman
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Schmidt
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Jan
authors.initials: J
authors.lastname: Claassen
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: E Sander
authors.initials: ES
authors.lastname: Connolly
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Stephan A
authors.initials: SA
authors.lastname: Mayer
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: Wahida
authors.initials: W
authors.lastname: Karmally
authors.affiliation: From the Section of Neurocritical Care and Emergency Neurology, Program in Trauma, Department of Neurology (N.B.), University of Maryland School of Medicine, Baltimore; and the Neurological Institute of New York (A.M., A.C., J.Z., J.M.S., J.C., E.S.C., S.A.M.), Institute of Human Nutrition (W.K.), and Division of Preventive Medicine and Nutrition, Department of Internal Medicine (D.S.), Columbia University College of Physicians and Surgeons, New York, NY.
authors.forename: David
authors.initials: D
authors.lastname: Seres
mesh_terms: D002097:C-Reactive Protein / Q000378:metabolism*; D003428:Cross Infection / Q000150:complications / Q000175:diagnosis / Q000378:metabolism; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D007249:Inflammation; D002532:Intracranial Aneurysm / Q000150:complications / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009584:Nitrogen / Q000378:metabolism*; D011228:Prealbumin / Q000378:metabolism*; D011379:Prognosis; D011446:Prospective Studies; D012146:Rest; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000175:diagnosis / Q000378:metabolism* / Q000628:therapy
chemical_list: D011228:Prealbumin; D002097:C-Reactive Protein; D009584:Nitrogen