title: Obstructive sleep apnea syndrome is a risk factor of hypertension.
abstract: BACKGROUND
  Some studies investigated the association between obstructive sleep apnea syndrome (OSAS) and hypertension risk. However, the results remained inconclusive. Thus, we performed a meta-analysis to clarify the association of OSAS and hypertension risk.
  
  
  METHODS
  Online electronic databases (PubMed and EMBASE) was searched. The strength of association between the OSAS and hypertension risk was assessed by calculating OR with 95% CI.
  
  
  RESULTS
  A total of 6 articles with 20,637 patients on OSAS and hypertension risk met the study inclusion criteria, and were included in the meta-analysis. OSAS was associated with a significantly increased risk of hypertension (OR=1.41; 95%CI, 1.29-1.8855 I2=20%). In the race subgroup analysis, Caucasians with OSAS had increased hypertension risk (OR=1.43; 95%CI, 1.29-1.59; I2=20%). In the subgroup analysis according to gender, male OSAS patients were significantly associated with risk of hypertension (OR=1.59; 95%CI, 1.16-2.17; I2=0%), while female OSAS patients were not significantly associated with risk of hypertension (OR=1.18; 95%CI, 0.80-1.73; I2=0%). All of the different severities of OSAS patients had an increased hypertension risk (mild: OR=1.26; 95%CI, 1.17-1.35; I2=45%; moderate: OR=1.50; 95%CI, 1.27-1.76; I2=46%; severe: OR=1.47; 95%CI, 1.33-1.64; I2=63%).
  
  
  CONCLUSIONS
  In conclusion, this meta-analysis suggested that OSAS may be associated with hypertension risk.
authors.affiliation: Department of Cardiology, China-Japan Union Hospital of Jilin University, Changchun, China - linbaisong2014@163.com.
authors.forename: Fanbo
authors.initials: F
authors.lastname: Meng
authors.forename: Jianghong
authors.initials: J
authors.lastname: Ma
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.forename: Baisong
authors.initials: B
authors.lastname: Lin
mesh_terms: D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000209:etiology*; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000150:complications*