title: Comparison of the effect of mesalazine and sulfasalazine on laboratory parameters: a retrospective observational study.
abstract: OBJECTIVE
  Mesalazine and sulfasalazine are commonly used drugs for the treatment of inflammatory bowel disease. However, there have been few reports with a strict statistical analysis comparing the effects of mesalazine and sulfasalazine on laboratory test results. Therefore, we designed a retrospective cohort study to investigate whether or not differences in clinical laboratory parameters exist between mesalazine and sulfasalazine users.
  
  
  METHODS
  We used data from the Clinical Data Warehouse of Nihon University School of Medicine to identify cohorts of new mesalazine users (n = 303) and sulfasalazine users (n = 67). We used a multivariate regression model and regression adjustment with the propensity score to adjust for differences in baseline covariates between mesalazine and sulfasalazine users, and compared serum levels of creatinine, urea nitrogen, aspartate aminotransferase, alanine aminotransferase, and hematological parameters including red and white blood cell counts and platelet count.
  
  
  RESULTS
  After adjustment, in sulfasalazine users, the mean values for all tests showed no significant change between baseline and during the exposure period. In contrast, in mesalazine users, the mean WBC and platelet counts during the exposure period were significantly lower than those at baseline. Furthermore, mean serum urea nitrogen level during the exposure period was significantly higher than that at baseline. In terms of mean changes in laboratory test values during the exposure period compared with baseline, the reduction of platelet count in mesalazine users was significant in comparison to that in sulfasalazine users.
  
  
  CONCLUSIONS
  Our findings suggested that the hematological adverse effects of mesalazine treatment might be greater than those of sulfasalazine treatment.
authors.affiliation: Department of Surgery, Nihon University School of Medicine, 2-11-1 Hikarigaoka, Nerima-ku, Tokyo, 179-0072, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Masuda
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Yayoi
authors.initials: Y
authors.lastname: Nishida
authors.forename: Satoshi
authors.initials: S
authors.lastname: Asai
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects* / Q000627:therapeutic use; D056486:Chemical and Drug Induced Liver Injury / Q000097:blood / Q000503:physiopathology; D015331:Cohort Studies; D016208:Databases, Factual; D005260:Female; D005759:Gastroenteritis / Q000097:blood / Q000188:drug therapy*; D006801:Humans; D007958:Leukocyte Count; D007970:Leukopenia / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology; D008297:Male; D019804:Mesalamine / Q000009:adverse effects* / Q000627:therapeutic use; D008875:Middle Aged; D010976:Platelet Count; D051437:Renal Insufficiency / Q000097:blood / Q000139:chemically induced / Q000503:physiopathology; D012189:Retrospective Studies; D012720:Severity of Illness Index; D012460:Sulfasalazine / Q000009:adverse effects* / Q000627:therapeutic use; D013921:Thrombocytopenia / Q000097:blood / Q000139:chemically induced* / Q000503:physiopathology; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D012460:Sulfasalazine; D019804:Mesalamine