title: Effect of continuous positive airway pressure on insulin growth factor-1 in patients with obstructive sleep apnea: a meta-analysis.
abstract: OBJECTIVE
  Obstructive sleep apnea (OSA) has been recognized as being associated with low level of insulin growth factor-1 (IGF-1). However, the impact of OSA treatment using continuous positive airway pressure (CPAP) on IGF-1 remains controversial. We performed a meta-analysis to determine whether effective CPAP therapy could increase IGF-1 levels.
  
  
  METHODS
  Two reviewers independently searched PubMed, Cochrane library, Embase and Web of Science before September 2014. Information on characteristics of subjects, study design and pre- and post-CPAP treatment of serum IGF-1 was extracted for analysis. Standardized mean difference (SMD) was used to analyze the summary estimates for CPAP therapy.
  
  
  RESULTS
  Six articles with 168 patients were included in this meta-analysis, including five observational studies and one randomized controlled study. The meta-analysis showed that CPAP was associated with a statistically significant increase in IGF-1 in OSA patients (SMD=-0.436, 95% confidence interval=-0.653 to -0.218, P=0.000).
  
  
  CONCLUSIONS
  This meta-analysis suggested that CPAP therapy was associated with an increase in IGF-1 in patients with OSA. Further large-scale, well-designed interventional investigations are needed to clarify this issue.
authors.affiliation: Department of Respiratory Medicine, Zhangzhou Affiliated Hospital of Fujian Medical University, No. 59, Shenglixi Road, Xiangcheng District, Zhangzhou, Fujian Province 350005, People's Republic of China.
authors.forename: Li-Da
authors.initials: LD
authors.lastname: Chen
authors.affiliation: Department of Respiratory Medicine, Zhangzhou Affiliated Hospital of Fujian Medical University, No. 59, Shenglixi Road, Xiangcheng District, Zhangzhou, Fujian Province 350005, People's Republic of China.
authors.forename: Li
authors.initials: L
authors.lastname: Lin
authors.affiliation: Department of Respiratory Medicine, the First Affiliated Hospital of Fujian Medical University, No. 20, Chazhong Road, Taijiang District, Fuzhou, Fujian Province 350005, People's Republic of China.
authors.forename: Jie-Feng
authors.initials: JF
authors.lastname: Huang
authors.affiliation: Department of Respiratory Medicine, the First Affiliated Hospital of Fujian Medical University, No. 20, Chazhong Road, Taijiang District, Fuzhou, Fujian Province 350005, People's Republic of China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Respiratory Medicine, Zhangzhou Affiliated Hospital of Fujian Medical University, No. 59, Shenglixi Road, Xiangcheng District, Zhangzhou, Fujian Province 350005, People's Republic of China.
authors.forename: Qiao-Zhen
authors.initials: QZ
authors.lastname: Xu
authors.affiliation: Department of Respiratory Medicine, Zhangzhou Affiliated Hospital of Fujian Medical University, No. 59, Shenglixi Road, Xiangcheng District, Zhangzhou, Fujian Province 350005, People's Republic of China. Electronic address: ljnzzsy123@163.com.
authors.forename: Jian-Nan
authors.initials: JN
authors.lastname: Liu
mesh_terms: D000328:Adult; D000368:Aged; D045422:Continuous Positive Airway Pressure; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D064887:Observational Studies as Topic; D016032:Randomized Controlled Trials as Topic; D020181:Sleep Apnea, Obstructive / Q000097:blood* / Q000453:epidemiology / Q000628:therapy*
chemical_list: D007334:Insulin-Like Growth Factor I
keywords: Continuous positive airway pressure; Insulin growth factor-1; Meta-analysis; Obstructive sleep apnea