title: Addition of theophylline or increasing the dose of inhaled corticosteroid in symptomatic asthma: a meta-analysis of randomized controlled trials.
abstract: OBJECTIVE
  Low-dose theophylline has anti-inflammatory effects. The aim of this study was to evaluate the effects of adding theophylline compared with increasing the dose of inhaled corticosteroid (ICS) on symptomatic asthma.
  
  
  METHODS
  The associated literature was acquired through deliberate searching and selected based on the established inclusion criteria for publications. The extracted data were further analyzed by a meta-analysis.
  
  
  RESULTS
  Four randomized, controlled, parallel studies were selected. Addition of theophylline produced a greater increase of forced expiratory volume in one second as %predicted (FEV₁pred) by 2.49% [95% confidence interval (CI) 1.99-3.00; z = 9.70; p < 0.001], compared with increasing the dose of ICS. There was no difference between the two treatments in terms of peak expiratory flow (PEF).
  
  
  CONCLUSIONS
  Addition of theophylline to ICS has similar therapeutic effects on improving lung function as increasing the dose of ICS in the treatment of symptomatic asthma.
authors.affiliation: Institute of Respiratory Diseases, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, China. wangyanflower@163.com
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Kexiong
authors.initials: K
authors.lastname: Lin
authors.forename: Changzheng
authors.initials: C
authors.lastname: Wang
authors.forename: Xiuqing
authors.initials: X
authors.lastname: Liao
mesh_terms: D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000627:therapeutic use*; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy*; D005541:Forced Expiratory Volume / Q000187:drug effects; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D013806:Theophylline / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000305:Adrenal Cortex Hormones; D018927:Anti-Asthmatic Agents; D013806:Theophylline