title: Effects of coffee and tea consumption on urinary incontinence in female twins.
abstract: OBJECTIVE
  To assess the effect of coffee and tea consumption on symptoms of urinary incontinence.
  
  
  METHODS
  Population-based study.
  
  
  METHODS
  The Swedish Twin Register.
  
  
  METHODS
  In 2005, all twins born between 1959 and 1985 in Sweden (n = 42,852) were invited to participate in a web-based survey to screen for common complex diseases and common exposures. The present study was limited to female twins with information about at least one urinary symptoms and coffee and tea consumption (n = 14,031).
  
  
  METHODS
  The association between coffee and tea consumption and urinary incontinence, as well as nocturia, was estimated as odds ratios (ORs) with 95% confidence intervals.
  
  
  RESULTS
  Women with a high coffee intake were at lower risk of any urinary incontinence (OR 0.78, 95% CI 0.64-0.98) compared with women not drinking coffee. Coffee intake and incontinence subtypes showed no significant associations whereas high tea consumption was specifically associated with a risk for overactive bladder (OR 1.34, 95% CI 11.07-1.67) and nocturia (OR 1.18, 95% CI 1.01-1.38). Results from co-twin control analysis suggested that the associations observed in logistic regression were mainly the result of familial effects.
  
  
  CONCLUSIONS
  This study suggests that coffee and tea consumption has a limited effect on urinary incontinence symptoms. Familial and genetic effects may have confounded the associations observed in previous studies.
authors.affiliation: Department of Medical Epidemiology and Biostatistics, Danderyd Hospital, Karolinska Institutet, Stockholm, Sweden. giorgio.tettamanti@ki.se
authors.forename: G
authors.initials: G
authors.lastname: Tettamanti
authors.forename: D
authors.initials: D
authors.lastname: Altman
authors.forename: N L
authors.initials: NL
authors.lastname: Pedersen
authors.forename: R
authors.initials: R
authors.lastname: Bellocco
authors.forename: I
authors.initials: I
authors.lastname: Milsom
authors.forename: A N
authors.initials: AN
authors.lastname: Iliadou
mesh_terms: D000328:Adult; D003069:Coffee / Q000009:adverse effects; D016001:Confidence Intervals; D005260:Female; D006306:Health Surveys; D006801:Humans; D016015:Logistic Models; D008875:Middle Aged; D053158:Nocturia / Q000139:chemically induced; D016017:Odds Ratio; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires; D013548:Sweden; D013662:Tea / Q000009:adverse effects*; D053201:Urinary Bladder, Overactive / Q000139:chemically induced*; D014549:Urinary Incontinence / Q000139:chemically induced*
chemical_list: D003069:Coffee; D013662:Tea