title: Can pretreatment serum calcium level predict the efficacy of methotrexate in the treatment of severe plaque psoriasis?
abstract: BACKGROUND
  The efficacy of methotrexate (MTX) varies in the treatment of psoriasis.
  
  
  OBJECTIVE
  We sought to identify an indicator from routine pretreatment tests to predict MTX efficacy in the treatment of psoriasis.
  
  
  METHODS
  In a retrospective analysis of 77 psoriatic patients, the correlation between MTX efficacy and pretreatment routine test results was analyzed with Spearman correlation. The potential risks were further evaluated with a linear regression model. Receiver operating characteristic analysis was performed to examine the effectiveness of serum total calcium (tCa) to predict the effect of MTX on psoriasis. The highest Youden index was used to determine the cutoff point, with which the positive and negative predictive values were calculated. Synergistic effects of MTX and calcium on keratinocyte growth and psoriasis-like mouse model were also investigated.
  
  
  RESULTS
  The pretreatment tCa level exhibited the closest association with MTX efficacy. The relative psoriasis improvement with tCa was 61.07% (95% confidence interval, 42.85-79.29; P < .001) and better improvements were observed in patients with higher tCa (r = 0.588; P < .002). MTX inhibited keratinocyte growth, which was enhanced synergistically by calcium. In a psoriasis-like mouse model, MTX strongly inhibited epidermis proliferation in the high-calcium group.
  
  
  CONCLUSIONS
  One limitation of our study is the relatively small sample size.
  
  
  CONCLUSIONS
  Pretreatment tCa level has the highest correlation with MTX efficacy, which might be useful in predicting beneficial treatment results in psoriasis. Larger studies are required to confirm our findings.
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Zhai
authors.affiliation: Department of Dermatology, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Chen
authors.affiliation: Institute of Toxicology, Third Military Medical University, Chongqing, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Trauma, Burns and Combined Injury, Research Institute of Surgery, Daping Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Yan
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Chunyou
authors.initials: C
authors.lastname: Wang
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Jinxin
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing, China.
authors.forename: Wenying
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing, China. Electronic address: zhushencq@hotmail.com.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Shen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D002118:Calcium / Q000097:blood*; D015331:Cohort Studies; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008297:Male; D008727:Methotrexate / Q000008:administration & dosage*; D051379:Mice; D008875:Middle Aged; D011237:Predictive Value of Tests; D011565:Psoriasis / Q000097:blood* / Q000188:drug therapy* / Q000473:pathology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D015415:Biomarkers; D002118:Calcium; D008727:Methotrexate
keywords: calcium; keratinocyte; methotrexate; predictor; psoriasis; treatment efficacy