title: Elevated inflammatory markers predict mortality in long-term ischemic stroke-survivors: a population-based prospective study.
abstract: OBJECTIVE
  High levels of inflammatory markers shortly after an ischemic stroke are associated with a worse prognosis. Whether inflammatory markers predict long-term mortality in stroke-survivors is less clear. We examined whether a persisting inflammatory response (levels of inflammatory markers >1 year after the stroke event) was associated with long-term mortality.
  
  
  METHODS
  We recruited participants from the Tromsø Study, Norway, in a nested case-control design. At baseline in 1997, white blood cell count (WBC), serum levels of fibrinogen, interleukin 6 (IL-6) and high sensitive C-reactive protein (hs-CRP) were analysed in 187 stroke-survivors, a median of 7.0 years (range 1-43) after the first-ever ischemic stroke, and in 243 stroke-free subjects. Cox proportional hazard regression model was used to examine whether inflammatory markers predicted all-cause mortality in both groups from 1997 to 2013.
  
  
  RESULTS
  During an average of 16 years follow-up, 117 (62.5 %) stroke-survivors and 107 (44.0 %) stroke-free subjects deceased (p for differences 0.005). In stroke-survivors, fibrinogen and log IL-6 predicted all-cause mortality after adjustment for age, sex, BMI, smoking, Frenchay activity index, comorbidity and use of statins (HRs 1.26; 9 5 % CI 1.05-1.51 and 2.02; 95 % CI 1.12-3.64, respectively). In stroke-free subjects log hs-CRP predicted all-cause mortality after additionally accounting for levels of cholesterol, blood pressure and use of blood pressure lowering drugs (HR 1.95; 95 % CI 1.26-2.99).
  
  
  CONCLUSIONS
  Fibrinogen and IL-6 were independent predictors of mortality in long-term stroke-survivors, whereas elevated hs-CRP predicted mortality in stroke-free subjects. Mortality risk prediction in stroke-survivors differed from that of stroke-free subjects.
authors.affiliation: Department of Internal Medicine, University Hospital of North Norway, Harstad, Norway. hanne.froyshov@unn.no.|Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway. hanne.froyshov@unn.no.
authors.forename: Hanne M
authors.initials: HM
authors.lastname: Frøyshov
authors.affiliation: Department of Health and Care Sciences, UiT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Åshild
authors.initials: Å
authors.lastname: Bjørnerem
authors.affiliation: Department of Geriatric Medicine, University Hospital of North Norway, Tromsø, Norway.|Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway.
authors.forename: Torgeir
authors.initials: T
authors.lastname: Engstad
authors.affiliation: Department of Clinical Medicine, UiT The Arctic University of Norway, Tromsø, Norway.|Department of Internal Medicine, University Hospital of North Norway, Tromsø, Norway.
authors.forename: Dag Seeger
authors.initials: DS
authors.lastname: Halvorsen
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D016022:Case-Control Studies; D015897:Comorbidity; D005260:Female; D005340:Fibrinogen / Q000032:analysis*; D005500:Follow-Up Studies; D006801:Humans; D007249:Inflammation / Q000097:blood*; D015850:Interleukin-6 / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000097:blood* / Q000401:mortality*; D017741:Survivors
chemical_list: D015415:Biomarkers; C508600:IL6 protein, human; D015850:Interleukin-6; D005340:Fibrinogen; D002097:C-Reactive Protein
keywords: CRP; High sensitive-CRP; Inflammatory markers; Interleukin-6; Mortality; Stroke