title: Recent surgery or invasive procedures and the risk of stroke.
abstract: OBJECTIVE
  A recent surgery may be one of the trigger factors precipitating stroke and transient ischemic attack (TIA). While stroke in cardiac and carotid surgery has been well studied, less is known on stroke risk after surgery outside the heart and brain supplying arteries. We tested the hypothesis that preceding non-neurosurgical, non-cardiothoracic, and non-carotid surgery and other interventions temporarily increase the risk of stroke and transient ischemic attack (TIA) and investigated the risk related to different time periods between interventions and stroke/TIA.
  
  
  METHODS
  In the Ludwigshafen Stroke Study, a population-based stroke registry, we assessed surgery and other interventions within the year preceding stroke and TIA. The risk factor profiles of patients with and without prior intervention were compared and rate ratios (RR) were calculated for different time periods with 91-365 days before stroke and TIA serving as reference period.
  
  
  RESULTS
  In 2006 and 2007, 803 patients without and 116 patients with non-neurosurgical, non-cardiothoracic, and non-carotid intervention within the preceding year were identified. Elective (n = 21) and posttraumatic orthopedic (n = 14), eye (n = 14), and visceral surgery (n = 11) dominated. Interventions within 0-30 days (n = 34; RR 4.72; 95% confidence interval (CI) 2.70-8.26) but not within 31-60 or 61-90 days before stroke/TIA were observed more often than in the reference period. Interventions were more common within day 8-30 before stroke/TIA (RR 3.26; 95% CI 1.66-6.39), particularly common within the preceding week (RR 9.52; 95% CI 3.77-24.1) and most common in the preceding 2 days (RR 27.1; 95% CI 5.97-123) as compared to the reference period. Atrial fibrillation (AF) but not other risk factors was more common in patients with interventions within 30 days (n = 15; 44.1%) as compared to patients with more antecedent interventions (n = 19; 23.2%, p = 0.022) and those without surgery (n = 222; 27.6%, p = 0.031). Interventions within 30 days before stroke/TIA, were associated with total ischemic stroke (RR 6.11; 95% CI 3.32-11.2), first-ever in a lifetime ischemic stroke (RR 5.62; 95% CI 2.83-11.1) and recurrent ischemic stroke (RR 7.50; 95% CI 2.88-19.6).
  
  
  CONCLUSIONS
  Recent non-cardiothoracic, non-carotid, and non-neurosurgical interventions are associated with an increased risk of stroke lasting for about 1 month and being particularly high within the first days. AF may be among the mechanisms linking interventions and stroke besides induction of a procoagulant state and interruption of medication.
authors.affiliation: Department of Neurology, University of Heidelberg, Heidelberg, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Urbanek
authors.forename: Frederick
authors.initials: F
authors.lastname: Palm
authors.forename: Florian
authors.initials: F
authors.lastname: Buggle
authors.forename: Joachim
authors.initials: J
authors.lastname: Wolf
authors.forename: Anton
authors.initials: A
authors.lastname: Safer
authors.forename: Heiko
authors.initials: H
authors.lastname: Becher
authors.forename: Armin J
authors.initials: AJ
authors.lastname: Grau
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000601:surgery; D016893:Carotid Stenosis / Q000601:surgery; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012306:Risk; D012307:Risk Factors; D020521:Stroke / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome