title: Insulin resistance is associated with a poor response to intravenous thrombolysis in acute ischemic stroke.
abstract: OBJECTIVE
  Insulin resistance (IR) may not only increase stroke risk, but could also contribute to aggravate stroke prognosis. Mainly through a derangement in endogenous fibrinolysis, IR could affect the response to intravenous thrombolysis, currently the only therapy proved to be efficacious for acute ischemic stroke. We hypothesized that high IR is associated with more persistent arterial occlusions and poorer long-term outcome after stroke thrombolysis.
  
  
  METHODS
  We performed a prospective, observational, longitudinal study in consecutive acute ischemic stroke patients presenting with middle cerebral artery (MCA) occlusion who received intravenous thrombolysis. Patients with acute hyperglycemia (≥155 mg/dL) receiving insulin were excluded. IR was determined during admission by the homeostatic model assessment index (HOMA-IR). Poor long-term outcome, as defined by a day 90 modified Rankin scale score ≥ 3, was considered the primary outcome variable. Transcranial Duplex-assessed resistance to MCA recanalization and symptomatic hemorrhagic transformation were considered secondary end points.
  
  
  RESULTS
  A total of 109 thrombolysed MCA ischemic stroke patients were included (43.1% women, mean age 71 years). The HOMA-IR was higher in the group of patients with poor outcome (P = 0.02). The probability of good outcome decreased gradually with increasing HOMA-IR tertiles (80.6%, 1st tertile; 71.4%, 2nd tertile; and 55.3%, upper tertile). A HOMA-IR in the upper tertile was independently associated with poor outcome when compared with the lower tertile (odds ratio [OR] 8.54 [95% CI 1.67-43.55]; P = 0.01) and was associated with more persistent MCA occlusions (OR 8.2 [1.23-54.44]; P = 0.029).
  
  
  CONCLUSIONS
  High IR may be associated with more persistent arterial occlusions and worse long-term outcome after acute ischemic stroke thrombolysis.
authors.affiliation: Department of Neurology, Stroke Unit, Hospital Clínico Universitario de Valladolid, University of Valladolid, Valladolid, Spain. aicsanz@hotmail.com
authors.forename: Ana I
authors.initials: AI
authors.lastname: Calleja
authors.forename: Pablo
authors.initials: P
authors.lastname: García-Bermejo
authors.forename: Elisa
authors.initials: E
authors.lastname: Cortijo
authors.forename: Rosa
authors.initials: R
authors.lastname: Bustamante
authors.forename: Esther
authors.initials: E
authors.lastname: Rojo Martínez
authors.forename: Enrique
authors.initials: E
authors.lastname: González Sarmiento
authors.forename: Rosa
authors.initials: R
authors.lastname: Fernández-Herranz
authors.forename: Juan F
authors.initials: JF
authors.lastname: Arenillas
mesh_terms: D000368:Aged; D001157:Arterial Occlusive Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000453:epidemiology; D004562:Electrocardiography; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D005500:Follow-Up Studies; D006801:Humans; D006943:Hyperglycemia / Q000188:drug therapy; D007333:Insulin Resistance; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012306:Risk; D020521:Stroke / Q000150:complications* / Q000188:drug therapy*; D015912:Thrombolytic Therapy / Q000009:adverse effects*; D016896:Treatment Outcome; D017585:Ultrasonography, Doppler, Transcranial
chemical_list: D005343:Fibrinolytic Agents