title: Acute kidney injury and risk of deep vein thrombosis and pulmonary embolism in Taiwan: A nationwide retrospective cohort study.
abstract: BACKGROUND
  Chronic kidney disease (CKD) increases risk for deep vein thrombosis (DVT) and pulmonary embolism (PE). However, few studies have investigated the relationship between acute kidney injury (AKI) and risk of DVT and PE. Therefore, we conducted a nationwide longitudinal cohort study to determine whether patients with AKI are associated with increased risk of developing DVT and PE.
  
  
  METHODS
  We included >30years-old inpatients (n=4734) receiving the diagnosis of AKI from 2000 to 2006 and their age-and sex-matched non-AKI inpatients using medical service in the same year (n=47.340). Diagnosis of DVT and PE was recorded within 5-year after the AKI event or index use of medical service. The hazard ratios were analyzed using Cox regression model and adjustments were made for demographic factors, selected comorbidities and treatments. A time-dependent covariate survival analysis was performed for variations of some comorbidities, treatments and hospitalization. Competing risk regression (CRR) model was also used to adjust the risk for death. Propensity score matching was used to minimize potential selection bias. We also performed sensitivity analysis to examine the effect of other possible residual confounding factors.
  
  
  RESULTS
  After adjusting for demographic characteristics, selected comorbidities and treatment, AKI remained a predisposing factor with a 1.44-fold (95% CI, 1.04-2.01) and 1.49-fold (95% CI, 1.12-1.97) increase in patients who were at a risk for developing DVT within 3 and 5years. AKI also remained a significant predisposing factor with a 2.66-fold (95% CI, 1.49-3.20) increase in patients who were at a risk for developing PE within 3years. However, there were no significant results for PE within 5years. The hazard ratios of time-dependent covariate survival analysis and CRR model showed the similar results.
  
  
  CONCLUSIONS
  Risk of DVT and PE is higher in patients with AKI than in the general population.
authors.affiliation: Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Department of Emergency, National Cheng Kung University Hospital, Tainan, Taiwan.
authors.forename: Tsung-Hang
authors.initials: TH
authors.lastname: Kuo
authors.affiliation: Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
authors.forename: Hsin-Yang
authors.initials: HY
authors.lastname: Li
authors.affiliation: Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan; Biostatistics Consulting Center, National Cheng Kung University Hospital, Tainan, Taiwan; Department of Public Health, College of Medicine, National Cheng-Kung University, Tainan, Taiwan. Electronic address: shlin922@mail.ncku.edu.tw.
authors.forename: Sheng-Hsiang
authors.initials: SH
authors.lastname: Lin
mesh_terms: D058186:Acute Kidney Injury / Q000150:complications* / Q000453:epidemiology; D000328:Adult; D015897:Comorbidity; D005260:Female; D006760:Hospitalization; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011655:Pulmonary Embolism / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013624:Taiwan / Q000453:epidemiology; D020246:Venous Thrombosis / Q000453:epidemiology*
keywords: Acute kidney injury; Cohort study; Deep vein thrombosis; National health insurance; Pulmonary embolism; Venous thromboembolism