title: Effect of antiplatelet and anticoagulant agents on risk of hospitalization for bleeding among a population of elderly nursing home stroke survivors.
abstract: OBJECTIVE
  Anticoagulants and antiplatelet agents are underutilized in the nursing home setting, perhaps because trials demonstrating treatment efficacy excluded people resembling those with long-term care needs. We sought to quantify the effect of antiplatelet and anticoagulant agents on risk of hospitalization for bleeding among an elderly nursing home population.
  
  
  METHODS
  We used a case-control design and identified first hospitalizations for bleeds using Medicare claims data from 1992 to 1997 as potential cases. Cases had at least one minimum data set (MDS) assessment within the 6 months before that hospitalization and a diagnosis of stroke. We identified up to 5 controls residing in the same facility during the same year and quarter as the case with a diagnosis of stroke. Our sample consisted of 3433 cases and 13 506 controls. Using the MDS, we identified standing orders for aspirin, dipyridamole, ticlopidine, or warfarin and used conditional logistic regression modeling to estimate the effect of these agents on risk of hospitalization for a bleed.
  
  
  RESULTS
  After adjustment, use of warfarin (odds ratio [OR], 1.26; 95% CI, 1.11 to 1.43) and combination therapy (OR, 1.34; 95% CI, 0.99 to 1.82) were associated with an increased risk of hospitalization for a bleed compared with nonusers. The odds of aspirin use was greater among cases than controls (OR, 1.07; 95% CI, 0.96 to 1.18) after adjustment.
  
  
  CONCLUSIONS
  Although present, the risk associated with use of these agents is small. The numbers needed to treat to harm 1 resident with aspirin and warfarin were 467 and 126, respectively.
authors.affiliation: Department of Community Health, Brown University, Providence, RI 02912, USA.
authors.forename: B J
authors.initials: BJ
authors.lastname: Quilliam
authors.forename: K L
authors.initials: KL
authors.lastname: Lapane
authors.forename: C B
authors.initials: CB
authors.lastname: Eaton
authors.forename: V
authors.initials: V
authors.lastname: Mor
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D000925:Anticoagulants / Q000009:adverse effects*; D001241:Aspirin / Q000009:adverse effects; D044383:Black People; D016022:Case-Control Studies; D016208:Databases, Factual; D004359:Drug Therapy, Combination; D004363:Drug Utilization / Q000706:statistics & numerical data; D005260:Female; D006470:Hemorrhage / Q000209:etiology*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D016015:Logistic Models; D008297:Male; D009735:Nursing Homes / Q000706:statistics & numerical data; D016017:Odds Ratio; D010975:Platelet Aggregation Inhibitors / Q000009:adverse effects*; D018570:Risk Assessment; D017678:Sex Distribution; D020521:Stroke / Q000188:drug therapy / Q000517:prevention & control*; D014859:Warfarin / Q000009:adverse effects; D044465:White People
chemical_list: D000925:Anticoagulants; D010975:Platelet Aggregation Inhibitors; D014859:Warfarin; D001241:Aspirin