title: Canadian cost- utility analysis of intravenous immunoglobulin for acute childhood idiopathic thrombocytopenic purpura.
abstract: BACKGROUND
  Idiopathic thrombocytopenic purpura (ITP) is a hematological disorder and can be classified as acute or chronic. The main goal of treatment for acute childhood ITP is the prevention of potentially fatal bleeding complications, the most serious of which is intracranial hemorrhage (ICH). Treatment options for acute childhood ITP include splenectomy, corticosteroids, and blood products such as intravenous immunoglobulin.
  
  
  OBJECTIVE
  The objective was to evaluate, from a Canadian perspective, the cost-effectiveness of intravenous immunoglobulin (IVIG) compared to alternative inpatient treatments for acute childhood idiopathic thrombocytopenic purpura (ITP).
  
  
  METHODS
  A Markov model with a lifelong time horizon was used to evaluate the costs and quality-adjusted life years (QALYs) for 5 treatments for children hospitalized for ITP: 1) no treatment; 2) IVIG; 3) Anti-D; 4) prednisone; and 5) methylprednisolone. The model predicted the probability of intracranial hemorrhage for each treatment strategy based on the time children spent with platelet counts <20,000µL. The time patients spent with platelet counts <20,000µL with each treatment was estimated by pooling data from published randomized clinical trials. In the basecase analysis, the cohort was assumed to weigh 20kg. Cost and utility model variables were based upon various literature sources. Parameter uncertainty was assessed using probabilistic sensitivity analysis.
  
  
  RESULTS
  The treatment strategies that comprised the efficiency frontier were prednisone, Anti-D and IVIG. The incremental cost per QALY was $53,333 moving from prednisone to Anti-D and $53,846 moving from Anti-D to IVIG. Results were sensitive to patient weight. If patient weight is 10kg, IVIG dominates all other strategies and if weight is increased to 30kg, the cost per QALY of IVIG is $163,708.
  
  
  CONCLUSIONS
  Based on common willingness to pay thresholds, IVIG might be considered a cost effective treatment for acute childhood ITP. Cost effectiveness is highly dependent on patient weight.
authors.affiliation: Programs for Assessment of Technology in Health (PATH) Research Institute, McMaster University, Hamilton, Ontario, Canada. blackhou@mcmaster.ca
authors.forename: Gord
authors.initials: G
authors.lastname: Blackhouse
authors.forename: Feng
authors.initials: F
authors.lastname: Xie
authors.forename: Mitchell A H
authors.initials: MA
authors.lastname: Levine
authors.forename: Kaitryn
authors.initials: K
authors.lastname: Campbell
authors.forename: Nazila
authors.initials: N
authors.lastname: Assasi
authors.forename: Kathryn
authors.initials: K
authors.lastname: Gaebel
authors.forename: Daria
authors.initials: D
authors.lastname: O'Reilly
authors.forename: Jean- Eric
authors.initials: J
authors.lastname: Tarride
authors.forename: Ron
authors.initials: R
authors.lastname: Goeree
mesh_terms: D000208:Acute Disease; D000305:Adrenal Cortex Hormones / Q000191:economics / Q000627:therapeutic use; D000367:Age Factors; D001835:Body Weight; D002170:Canada; D002648:Child; D003362:Cost-Benefit Analysis; D016527:Drug Costs; D017721:Hospital Costs; D006760:Hospitalization / Q000191:economics; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000191:economics* / Q000627:therapeutic use*; D007155:Immunologic Factors / Q000191:economics* / Q000627:therapeutic use*; D020300:Intracranial Hemorrhages / Q000191:economics / Q000209:etiology / Q000517:prevention & control; D008390:Markov Chains; D018803:Models, Economic; D010976:Platelet Count; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000097:blood / Q000150:complications / Q000188:drug therapy* / Q000191:economics*; D019057:Quality-Adjusted Life Years; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D000305:Adrenal Cortex Hormones; D016756:Immunoglobulins, Intravenous; D007155:Immunologic Factors