title: Higher dose of warfarin for patients with pulmonary embolism complicated by obstructive sleep apnea hypopnea syndrome.
abstract: BACKGROUND
  The concomitant prevalence of obstructive sleep apnea hypopnea syndrome (OSAHS) and pulmonary embolism (PE) is strikingly high, and therefore we studied the patients with PE to determine whether those who had OSHAS required greater warfarin doses to achieve a therapeutic international normalized ratio (INR).
  
  
  METHODS
  By using computer tomographic pulmonary angiography or pulmonary angiography, we identified and recruited 97 patients with PE and all underwent polysomnography. Warfarin was initiated at a dose of 3 mg/day and modified to adjust the INR to the range of 2.0-3.0.
  
  
  RESULTS
  OSAHS patients (n = 32) required a significantly higher dose of warfarin than their non-OSAHS counterparts (5.01 mg vs 3.61 mg, P < .001). This difference still existed between the two groups after adjusting for covariates (achieved INR value and weight). Logistic analysis suggested that OSAHS was an independent risk factor for high dose warfarin (OR 5.715, P < .001). On admission, OSAHS patients had a lower mean value of INR and prothrombin time but higher plasminogen (PLG) activity compared to non-OSAHS patients. Other coagulation indices were not significantly different between the two groups. Except for the PLG activity (r = .273, P = .026), the correlation between the warfarin dose and the baseline coagulating indices wasn't significant.
  
  
  CONCLUSIONS
  Our findings indicate that factors associated with OSAHS, such as hypercoagulation, may explain the need for higher doses of warfarin in treating patients with PE.
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Xie
authors.initials: X
authors.lastname: Jiang
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Yongxiang
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Wei
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Zhang
authors.initials: Z
authors.lastname: Xiangfeng
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Li
authors.initials: L
authors.lastname: Jie
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China.
authors.forename: Rehmatullah
authors.initials: R
authors.lastname: Achakzai
authors.affiliation: Pulmonary-heart Center of Beijing An Zhen Hospital, Capital Medical University, Beijing, China. Electronic address: 34447278@qq.com.
authors.forename: Liu
authors.initials: L
authors.lastname: Shuang
mesh_terms: D000368:Aged; D001835:Body Weight; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D011446:Prospective Studies; D011655:Pulmonary Embolism / Q000150:complications / Q000188:drug therapy*; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000150:complications*; D014859:Warfarin / Q000008:administration & dosage*
chemical_list: D014859:Warfarin
keywords: Obstructive sleep apnea hypopnea syndrome; Pulmonary embolism; Warfarin