title: Systematic review with meta-analysis: the gastrointestinal benefits of COX-2 selective inhibitors with concomitant use of low-dose aspirin.
abstract: It is uncertain whether concurrent use of low-dose aspirin removes the gastrointestinal benefit displayed by COX-2 selective inhibitors (coxibs) when compared to traditional nonsteroidal anti-inflammatory drugs (NSAIDs).
  
  
  
  To evaluate the gastrointestinal risks associated with coxibs and traditional NSAIDs and the interaction with concurrent use of low-dose aspirin.
  
  
  
  We searched MEDLINE, EMBASE and the Cochrane Library through April 2016 to identify randomised trials comparing the gastrointestinal risk between coxibs and traditional NSAIDs in patients taking or not taking low-dose aspirin. Results were combined using random effects meta-analysis. Subgroup analyses by concurrent use of aspirin were undertaken.
  
  
  
  Eleven trials (84 150 participants) were included. The overall relative risk (RR) of coxibs vs. traditional NSAIDs for complicated gastrointestinal events was 0.54 (95% CI, confidence interval 0.32-0.92), with a significant subgroup difference (P = 0.04) according to concurrent use of aspirin (used: RR = 0.96, 95% CI 0.66-1.24; not used: RR = 0.33, 95% CI 0.14-0.83). The overall RR for clinical gastrointestinal events was 0.59 (95% CI 0.47-0.75), with a significant subgroup difference according to aspirin usage (P = 0.008; used: RR = 0.77, 95% CI 0.62-0.95; not used: RR = 0.50, 95% CI 0.39-0.64). Overall coxibs were associated with significantly lower risk of symptomatic ulcers (RR = 0.60, 95% CI 0.50-0.72) and endoscopic ulcers (RR = 0.29, 95% CI 0.16-0.53) than traditional NSAIDs; a significant subgroup difference was shown for endoscopic ulcers (P = 0.05) but not for symptomatic ulcers (P = 0.27).
  
  
  
  Concomitant use of low-dose aspirin reduces but does not completely eliminate the gastrointestinal benefit of coxibs over traditional NSAIDs.
authors.affiliation: School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.|Municipal Key Laboratory for Health Risk Analysis, Shenzhen Research Institute of the Chinese University of Hong Kong, Shenzhen, Guangdong, China.|School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: J Q
authors.initials: JQ
authors.lastname: Yuan
authors.affiliation: Department of Gastroenterology, Songgang Hospital, Shenzhen, Guangdong, China.
authors.forename: M
authors.initials: M
authors.lastname: Yang
authors.affiliation: School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.
authors.forename: D E
authors.initials: DE
authors.lastname: Threapleton
authors.affiliation: Department of Gastroenterology, General Hospital of Shenyang Military Region, Liaoning, China.
authors.forename: X S
authors.initials: XS
authors.lastname: Qi
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, Anhui, China.
authors.forename: D Q
authors.initials: DQ
authors.lastname: Ye
authors.affiliation: School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong. maochen@cuhk.edu.hk.|Municipal Key Laboratory for Health Risk Analysis, Shenzhen Research Institute of the Chinese University of Hong Kong, Shenzhen, Guangdong, China. maochen@cuhk.edu.hk.
authors.forename: C
authors.initials: C
authors.lastname: Mao
authors.affiliation: School of Public Health and Primary Care, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong. jltang@cuhk.edu.hk.|Municipal Key Laboratory for Health Risk Analysis, Shenzhen Research Institute of the Chinese University of Hong Kong, Shenzhen, Guangdong, China. jltang@cuhk.edu.hk.
authors.forename: J L
authors.initials: JL
authors.lastname: Tang
authors.affiliation: School of Social and Community Medicine, University of Bristol, Bristol, UK.
authors.forename: J P T
authors.initials: JP
authors.lastname: Higgins
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000009:adverse effects; D001241:Aspirin / Q000008:administration & dosage* / Q000009:adverse effects; D052246:Cyclooxygenase 2 Inhibitors / Q000008:administration & dosage* / Q000009:adverse effects; D005767:Gastrointestinal Diseases / Q000453:epidemiology; D006801:Humans; D016032:Randomized Controlled Trials as Topic
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D052246:Cyclooxygenase 2 Inhibitors; D001241:Aspirin