title: Postoperative complications after percutaneous nephrolithotomy: a contemporary analysis by insurance status in the United States.
abstract: OBJECTIVE
  No published data to date have assessed the insurance-related disparities among patients undergoing percutaneous nephrolithotomy (PCNL). Our objective was to examine whether being uninsured is associated with more perioperative complications after PCNL in the United States and to determine possible risk factors that influence PCNL outcomes.
  
  
  METHODS
  This retrospective cohort study evaluated 13,982 patients who underwent PCNL and were included in Nationwide Inpatient Sample from 1998 through 2010. The main outcome measure was ≥1 perioperative complication stratified by insurance status. Associations between this outcome and insurance status were examined using logistic regression models.
  
  
  RESULTS
  The overall percentage of patients with ≥1 perioperative complication after PCNL was 14.4% (n=2008). When stratified by insurance status, the unadjusted analysis showed significantly higher complication rates among Medicare (17.1%) and Medicaid (16.9%) beneficiaries than privately insured (12.3%) and uninsured (13.4%) patients (P<0.001). In a fully adjusted analysis of patients without medical comorbidity, however, these differences were no longer statistically significant, even when stratified by hospital teaching status. Multivariable-adjusted analysis of preoperative medical comorbidity showed that pulmonary disorders (odds ratio [OR], 7.77; 95% confidence interval [CI], 4.54-13.31), coagulopathy (OR, 6.16; 95% CI, 4.27-8.89), deficiency anemias (OR, 3.82; 95% CI, 3.29-4.44), and paralysis (OR, 2.16; 95% CI, 1.78-2.61) were the strongest predictors of ≥1 perioperative complication.
  
  
  CONCLUSIONS
  Perioperative morbidity after PCNL varied significantly with insurance status, but this variation was explained mostly by differences in overall health status.
authors.affiliation: Department of Urology, Mayo Clinic Hospital , Phoenix, Arizona.
authors.forename: Mark D
authors.initials: MD
authors.lastname: Tyson
authors.forename: Mitchell R
authors.initials: MR
authors.lastname: Humphreys
mesh_terms: D000328:Adult; D000368:Aged; D003365:Costs and Cost Analysis; D005260:Female; D006801:Humans; D015994:Incidence; D019458:Insurance Coverage; D007348:Insurance, Health / Q000191:economics*; D007669:Kidney Calculi / Q000191:economics / Q000601:surgery*; D016015:Logistic Models; D008297:Male; D008484:Medicaid / Q000191:economics; D017057:Medically Uninsured; D006278:Medicare / Q000191:economics; D008875:Middle Aged; D009403:Nephrostomy, Percutaneous / Q000009:adverse effects* / Q000191:economics; D016017:Odds Ratio; D011183:Postoperative Complications / Q000191:economics* / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D014481:United States / Q000453:epidemiology