title: Change over time of bowel habit in irritable bowel syndrome: a prospective, observational, 1-year follow-up study (RITMO study).
abstract: BACKGROUND
  Evolution of bowel habit in irritable bowel syndrome (IBS) is not well known.
  
  
  OBJECTIVE
  To evaluate the change over time of bowel habit in IBS patients followed-up during 1 year.
  
  
  METHODS
  Five hundred and seventeen patients with IBS were prospectively included in an observational study with five evaluations over a 1-year period. Symptoms were recorded daily in diary cards during four 4-week periods along the study. Bristol Stool Scale (BSS) was used to define bowel habit.
  
  
  RESULTS
  Four-hundred patients completed the study. Rome II showed low-moderate agreement (42%) with BSS to define bowel habit. Frequency of constipation and diarrhoea showed little changes throughout the study. Over 50% of the patients had the same bowel habit when each diary was compared with the next one. A third of patients maintained the same habit throughout the study. Most changes occurred from/to mixed or unsubtyped IBS. Only 14% of cases changed from constipation to diarrhoea or vice versa. This change was associated to female gender (OR: 2.65).
  
  
  CONCLUSIONS
  The frequency of constipation and diarrhoea remains relatively stable over time. Changes in IBS subtypes are common, but changes between constipation and diarrhoea are rare. Alternating IBS is more frequent in women.
authors.affiliation: Digestive Medicine Department, Hospital Universitari La Fe, Valencia, Spain. garrigues_vic@gva.es
authors.forename: V
authors.initials: V
authors.lastname: Garrigues
authors.forename: F
authors.initials: F
authors.lastname: Mearin
authors.forename: X
authors.initials: X
authors.lastname: Badía
authors.forename: A
authors.initials: A
authors.lastname: Balboa
authors.forename: J
authors.initials: J
authors.lastname: Benavent
authors.forename: A
authors.initials: A
authors.lastname: Caballero
authors.forename: E
authors.initials: E
authors.lastname: Domínguez
authors.forename: M
authors.initials: M
authors.lastname: Díaz-Rubio
authors.forename: M
authors.initials: M
authors.lastname: Roset
authors.forename: M
authors.initials: M
authors.lastname: Figueras
authors.forename: M
authors.initials: M
authors.lastname: Cucala
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003248:Constipation / Q000209:etiology* / Q000503:physiopathology; D003672:Defecation; D003967:Diarrhea / Q000209:etiology* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013030:Spain; D013997:Time Factors