title: The association between obesity and urinary tract infection.
abstract: BACKGROUND
  Few studies examined the relationship between obesity and urinary tract infection (UTI), showing inconsistent results. This study aims to examine the association between obesity and UTI, and to assess whether this association is independent of diabetes mellitus and 25(OH)D level.
  
  
  METHODS
  Using the computerized database of the largest healthcare provider in Israel, we identified a cohort of subjects ≥18years old with available BMI and serum 25(OH)D level measurements between January 2009 and December 2009. The cohort was followed for the first UTI diagnosis from January 2010 through June 2011. Cox proportional hazard model was used to test the relationship between obesity and UTI.
  
  
  RESULTS
  During follow-up, 25,145/110,736 (22.7%) females, and 4032/42,703 (9.4%) males had UTI. The crude HR for UTI in those with BMI≥50 compared to BMI<25 was 2.54 (95% CI, 1.50-4.30) in males and 1.39 (1.14-1.69) in females. After adjusting for age, 25(OH)D level, and history of diabetes mellitus, the HR for UTI in those with BMI≥50 compared to BMI<25 was 2.38 (1.40-4.03) in males and 1.25 (1.03-1.52) in females. The HR for those in the lowest quartile of serum 25(OH)D compared to the highest quartile was 1.23 (1.13-1.35) in males and 0.98 (0.95-1.02) in females. The HR for subjects with diabetes was 1.23 (1.16-1.32) in males, and 1.25 (1.20-1.28) in females.
  
  
  CONCLUSIONS
  Obesity is independently associated with UTI particularly in males. Low serum 25(OH)D levels are associated with increased risk of UTI in males.
authors.affiliation: Department of Community Medicine and Epidemiology, Carmel Medical Center, Clalit Health Services, and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel. saliba_wa@clalit.org.il
authors.forename: Walid
authors.initials: W
authors.lastname: Saliba
authors.forename: Ofra
authors.initials: O
authors.lastname: Barnett-Griness
authors.forename: Gad
authors.initials: G
authors.lastname: Rennert
mesh_terms: D017677:Age Distribution; D015992:Body Mass Index; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000453:epidemiology; D011159:Population Surveillance; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D012737:Sex Factors; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000209:etiology*