title: Cigarette smoking and risk of hip fracture in women: a meta-analysis of prospective cohort studies.
abstract: OBJECTIVE
  Whether cigarette smoking can increase the risk of hip fracture in women is unclear. This meta-analysis, which pooled results from 10 prospective cohort studies, was performed to derive a more precise estimation between cigarette smoking and the risk of hip fracture in women.
  
  
  METHODS
  Pubmed, Cochrane Central Register of Controlled Trials and ISI Web of Science were systematically searched to identify relevant studies. A meta-analysis was performed to examine the association among 10 studies. The pooled risk estimates were calculated by using both random- and fixed-effects model. Heterogeneity among articles and their publications bias were also tested. All of the statistical analyses were performed using the software programs STATA (version 12.0).
  
  
  RESULTS
  Relative risk was significantly increased in current female smokers (pooled RR, 1.30; 95%CI, 1.16-1.45). The association was significant among the high-dose smokers (more than 15 cigarettes per day) while not among the low-does smokers (less than 15 cigarettes per day). Omission of any single study had little effect on the pooled risk estimate. Former smokers had a similar RR of hip fracture (RR, 1.02; 95%CI, 0.93-1.11) to published papers. Smoking cessation for ≥10 years leads to a significant decline in risk.
  
  
  CONCLUSIONS
  Smoking is associated with an increased hip fracture risk in women. Cessation of smoking for ≥10 years had a decreased impact on risk of hip fracture. Given the inconsistency among the studies in the choice of adjustments, the associations between cigarette smoking and risk of hip fracture in women await further investigation.
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: GuangSi_S@163.com.
authors.forename: Guang Si
authors.initials: GS
authors.lastname: Shen
authors.affiliation: Department of Image, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: Yong_L3@163.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, The Affiliated Hospital of Jiangsu University, Zhenjiang, China. Electronic address: GuoY_Z@163.com.
authors.forename: GuoYang
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: HBinZh@163.com.
authors.forename: Hai Bin
authors.initials: HB
authors.lastname: Zhou
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: ZongGangX@163.com.
authors.forename: Zong Gang
authors.initials: ZG
authors.lastname: Xie
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: WeiXu088@163.COM.
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: HaiN_Ch@126.com.
authors.forename: Hai Nan
authors.initials: HN
authors.lastname: Chen
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: QiRongD@163.com.
authors.forename: Qi Rong
authors.initials: QR
authors.lastname: Dong
authors.affiliation: Department of Orthopaedics, The Second Affiliated Hospital of Soochow University, Suzhou, China. Electronic address: YouJ_XU@163.com.
authors.forename: You Jia
authors.initials: YJ
authors.lastname: Xu
mesh_terms: D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006620:Hip Fractures / Q000453:epidemiology / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D010024:Osteoporosis / Q000097:blood / Q000453:epidemiology / Q000209:etiology*; D011446:Prospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000097:blood / Q000453:epidemiology; D000074606:Smoking Prevention; D014807:Vitamin D / Q000097:blood
chemical_list: D014807:Vitamin D
keywords: Hip fractures; Meta-analysis; Osteoporosis; Smoking; Women