title: Predicting the probability of survival in acute paraquat poisoning.
abstract: BACKGROUND
  Paraquat (PQ) concentration-time data have been used to predict prognosis for 3 decades. The aim of this study was to find a more accurate method to predict the probability of survival.
  
  
  METHODS
  This study included 788 patients with PQ poisoning who were diagnosed using plasma PQ concentration between January 2005 and August 2012. We divided these patients into 2 groups (survivors vs. nonsurvivors), compared their clinical characteristics, and analyzed the predictors of survival.
  
  
  RESULTS
  The mean age of the included patients was 57 years (range, 14-95 years). When we compared clinical characteristics between survivors (n = 149, 19%) and nonsurvivors (n = 639, 81%), survivors were younger (47 ± 14 years vs. 59 ± 16 years) and had lower plasma PQ concentrations (1.44 ± 8.77 μg/mL vs. 80.33 ± 123.15 μg/mL) than nonsurvivors. On admission, serum creatinine was lower in survivors than in nonsurvivors (0.95 ± 0.91 mg/dL vs. 1.88 ± 1.27 mg/dL). In multivariate logistic regression analysis, age and logarithmically converted serum creatinine [ln(Cr)], [ln(time)], and [ln(PQ)] were assessed as prognostic factors to predict survival in PQ poisoning. The predicted probability of survival using significant prognostic factors was exp (logit)/[1 + exp(logit)], where logit = -1.347 + [0.212 × sex (male = 1, female = 0)] + (0.032 × age) + [1.551 × ln(Cr)] + [0.391 × ln(hours since ingestion)] + [1.076 × ln(plasma PQ μg/mL)]. With this equation, the sensitivity and specificity were 86.5% and 98.7%, respectively.
  
  
  CONCLUSIONS
  Age, ln(Cr), ln(time), and ln(PQ) were important prognostic factors in PQ poisoning, and our equation can be helpful to predict the survival in acute PQ poisoning patients.
authors.affiliation: Division of Nephrology & Toxicology, Department of Internal Medicine, Presbyterian Medical Center, Jeonju, Korea.
authors.forename: In O
authors.initials: IO
authors.lastname: Sun
authors.affiliation: Department of Biochemistry, Christian Medical Research Center, Jeonju, Korea.
authors.forename: Sung Hye
authors.initials: SH
authors.lastname: Shin
authors.affiliation: Division of Nephrology & Toxicology, Department of Internal Medicine, Presbyterian Medical Center, Jeonju, Korea.
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Yoon
authors.affiliation: Division of Nephrology & Toxicology, Department of Internal Medicine, Presbyterian Medical Center, Jeonju, Korea; Department of Biochemistry, Christian Medical Research Center, Jeonju, Korea.
authors.forename: Kwang Young
authors.initials: KY
authors.lastname: Lee
keywords: Creatinine; Logistic models; Paraquat; Prognosis