title: Patients with ankylosing spondylitis have been breast fed less often than healthy controls: a case-control retrospective study.
abstract: OBJECTIVE
  Ankylosing spondylitis (AS) is a chronic inflammatory disease affecting the spine and pelvis of young adults. On the HLA-B27 genetic background, the occurrence of AS is influenced by the intestinal microbiota. The goal of our study was to test whether breast feeding, which influences microbiota, can prevent the development of AS.
  
  
  METHODS
  First, 203 patients with HLA-B27-positive AS fulfilling the modified New York criteria were recruited in the Department of Rheumatology, Ste Marguerite hospital in Marseilles. A total of 293 healthy siblings were also recruited to make up a control group within the same families. Second, 280 healthy controls, and 100 patients with rheumatoid arthritis and their siblings were recruited. The data collected were age, gender, number of brothers and sisters, age at disease onset, type and duration of feeding (breast or bottle).
  
  
  RESULTS
  Patients with AS had been breast fed less often than healthy controls. In families where children were breast fed, the patients with AS were less often breast fed than their healthy siblings (57% vs 72%), giving an OR for AS onset of 0.53 (95% CI (0.36 to 0.77), p value=0.0009). Breast feeding reduced familial prevalence of AS. The frequency of breast feeding was similar in the AS siblings and in the 280 unrelated controls. However, patients with AS were less often breast fed compared with the 280 unrelated controls (OR 0.6, 95% CI (0.42 to 0.89), p<0.01).
  
  
  CONCLUSIONS
  Our study suggests a breastfeeding-induced protective effect on the occurrence of AS. To our knowledge, this is the first study of breastfeeding history in patients with AS.
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France.
authors.forename: J
authors.initials: J
authors.lastname: Montoya
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France.
authors.forename: N B
authors.initials: NB
authors.lastname: Matta
authors.affiliation: Departments of Nutrition, Obesity and Risk of Thrombosis, INSERM, UMR1062, Aix-Marseille University, Marseille, France Laboratory of Hematology, AP-HM, Hopital Timone, Marseille, France.
authors.forename: P
authors.initials: P
authors.lastname: Suchon
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France.
authors.forename: M C
authors.initials: MC
authors.lastname: Guzian
authors.affiliation: INSERM UMRs 1097, Aix Marseille Université, Marseille, France.
authors.forename: N C
authors.initials: NC
authors.lastname: Lambert
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France.
authors.forename: J P
authors.initials: JP
authors.lastname: Mattei
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France.
authors.forename: S
authors.initials: S
authors.lastname: Guis
authors.affiliation: INSERM U987 and Université de Versailles St.-Quentin-en-Yvelines, Montigny-le-Bretonneux, France Hôpital Ambroise Paré, AP-HP, and Université de Versailles St.-Quentin-en-Yvelines, Boulogne-Billancourt, France Laboratoire d'Excellence Inflamex, Université Paris Diderot, Sorbonne Paris Cité, Paris, France.
authors.forename: M
authors.identifier: http://orcid.org/0000-0002-6932-9395
authors.initials: M
authors.lastname: Breban
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France INSERM UMRs 1097, Aix Marseille Université, Marseille, France.
authors.forename: J
authors.initials: J
authors.lastname: Roudier
authors.affiliation: Department of Rheumatology, IML, AP-HM, Marseille, France INSERM UMRs 1097, Aix Marseille Université, Marseille, France.
authors.forename: N
authors.initials: N
authors.lastname: Balandraud
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000517:prevention & control; D001903:Bottle Feeding / Q000706:statistics & numerical data; D001942:Breast Feeding / Q000706:statistics & numerical data*; D005260:Female; D000069196:Gastrointestinal Microbiome; D020022:Genetic Predisposition to Disease; D015796:HLA-B27 Antigen / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D035781:Siblings; D013167:Spondylitis, Ankylosing / Q000235:genetics / Q000382:microbiology / Q000517:prevention & control*; D013997:Time Factors; D055815:Young Adult
chemical_list: D015796:HLA-B27 Antigen
keywords: Ankylosing Spondylitis; Epidemiology; Outcomes research