title: Breastfeeding and Risk of Rheumatoid Arthritis: A Systematic Review and Metaanalysis.
abstract: OBJECTIVE
  Previous studies have examined the association between breastfeeding and rheumatoid arthritis (RA), but their results were inconsistent. The aim of this study was to perform a metaanalysis to clarify the effect of breastfeeding on RA risk.
  
  
  METHODS
  The PubMed, EMBASE, Chinese National Knowledge Infrastructure, and Wanfang databases were searched for relevant studies published up to September 10, 2014. Data were extracted, and multivariable-adjusted OR with 95% CI were pooled in the random-effects model.
  
  
  RESULTS
  A total of 6 studies were included in the metaanalysis (RA cases: 1672, sample size: 143,670). Overall, an inverse association between breastfeeding and RA was observed (OR 0.675, 95% CI 0.493-0.924, p = 0.014). In the subgroup analysis, decreased RA risk was also found in both breastfeeding 1-12 months (OR 0.783, 95% CI 0.641-0.957, p = 0.015) and breastfeeding > 12 months (OR 0.579, 95% CI 0.462-0.726, p < 0.0005). Sensitivity analysis and cumulative analysis further strengthened the validity of the results. No publication bias was found in this metaanalysis.
  
  
  CONCLUSIONS
  This metaanalysis suggests that breastfeeding is associated with a lower risk of RA, no matter if breastfeeding time is longer or shorter than 12 months.
authors.affiliation: From the Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing; Department of Anatomy and Histoembryology, Xuzhou Medical College, Xuzhou; Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China.H. Chen, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University; J. Wang, MD, Department of Anatomy and Histoembryology, Xuzhou Medical College, and Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; W. Zhou, PhD; H. Yin, PhD, Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; M. Wang, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Chen
authors.affiliation: From the Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing; Department of Anatomy and Histoembryology, Xuzhou Medical College, Xuzhou; Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China.H. Chen, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University; J. Wang, MD, Department of Anatomy and Histoembryology, Xuzhou Medical College, and Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; W. Zhou, PhD; H. Yin, PhD, Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; M. Wang, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.affiliation: From the Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing; Department of Anatomy and Histoembryology, Xuzhou Medical College, Xuzhou; Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China.H. Chen, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University; J. Wang, MD, Department of Anatomy and Histoembryology, Xuzhou Medical College, and Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; W. Zhou, PhD; H. Yin, PhD, Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; M. Wang, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University.
authors.forename: Wang
authors.initials: W
authors.lastname: Zhou
authors.affiliation: From the Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing; Department of Anatomy and Histoembryology, Xuzhou Medical College, Xuzhou; Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China.H. Chen, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University; J. Wang, MD, Department of Anatomy and Histoembryology, Xuzhou Medical College, and Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; W. Zhou, PhD; H. Yin, PhD, Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; M. Wang, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University.
authors.forename: Huabin
authors.initials: H
authors.lastname: Yin
authors.affiliation: From the Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing; Department of Anatomy and Histoembryology, Xuzhou Medical College, Xuzhou; Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University, Shanghai, China.H. Chen, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University; J. Wang, MD, Department of Anatomy and Histoembryology, Xuzhou Medical College, and Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; W. Zhou, PhD; H. Yin, PhD, Department of Bone Tumor Surgery, Changzheng Hospital, Second Military Medical University; M. Wang, MM, Division of Rheumatology, Zhongda Hospital, School of Medicine, Southeast University. wmm3272142@163.com.
authors.forename: Meimei
authors.initials: M
authors.lastname: Wang
mesh_terms: D001172:Arthritis, Rheumatoid / Q000453:epidemiology*; D001942:Breast Feeding; D006801:Humans; D012306:Risk; D013997:Time Factors
keywords: BREASTFEEDING; METAANALYSIS; RHEUMATOID ARTHRITIS; RISK