title: Irritable bowel syndrome subtypes: Clinical and psychological features, body mass index and comorbidities.
abstract: BACKGROUND
  Irritable bowel syndrome (IBS) is classified into subtypes according to bowel habit.
  
  
  OBJECTIVE
  To investigate whether there are differences in clinical features, comorbidities, anxiety, depression and body mass index (BMI) among IBS subtypes.
  
  
  METHODS
  The study group included 113 consecutive patients (mean age: 48 ± 11 years; females: 94) with the diagnosis of IBS. All of them answered a structured questionnaire for demographic and clinical data and underwent upper endoscopy. Anxiety and depression were assessed by the Hospital Anxiety and Depression scale (HAD).
  
  
  RESULTS
  The distribution of subtypes was: IBS-diarrhea (IBS-D), 46%; IBS-constipation (IBS-C), 32%, and mixed IBS (IBS-M), 22%. IBS overlap with gastroesophageal reflux disease (GERD), functional dyspepsia, chronic headache and fibromyalgia occurred in 65.5%, 48.7%, 40.7% and 22.1% of patients, respectively. Anxiety and/or depression were found in 81.5%. Comparisons among subgroups showed that bloating was significantly associated with IBS-M compared to IBS-D (odds ratio-OR-5.6). Straining was more likely to be reported by IBS-M (OR 15.3) and IBS-C (OR 12.0) compared to IBS-D patients, while urgency was associated with both IBS-M (OR 19.7) and IBS-D (OR 14.2) compared to IBS-C. In addition, IBS-M patients were more likely to present GERD than IBS-D (OR 6.7) and higher scores for anxiety than IBS-C patients (OR 1.2). BMI values did not differ between IBS-D and IBS-C.
  
  
  CONCLUSIONS
  IBS-M is characterized by symptoms frequently reported by both IBS-C (straining) and IBS-D (urgency), higher levels of anxiety, and high prevalence of comorbidities. These features should be considered in the clinical management of this subgroup.
authors.affiliation: Gastroenterology Unit, State University of Campinas, Brazil.
authors.forename: Cristiane
authors.initials: C
authors.lastname: Kibune Nagasako
authors.affiliation: Gastroenterology Unit, State University of Campinas, Brazil.
authors.forename: Ciro
authors.initials: C
authors.lastname: Garcia Montes
authors.affiliation: Gastroenterology Unit, State University of Campinas, Brazil.
authors.forename: Sônia Letícia
authors.initials: SL
authors.lastname: Silva Lorena
authors.affiliation: Gastroenterology Unit, State University of Campinas, Brazil.
authors.forename: Maria Aparecida
authors.initials: MA
authors.lastname: Mesquita
mesh_terms: D000328:Adult; D001007:Anxiety / Q000175:diagnosis / Q000209:etiology; D015992:Body Mass Index; D001938:Brazil / Q000453:epidemiology; D015897:Comorbidity; D003248:Constipation / Q000209:etiology; D003863:Depression / Q000175:diagnosis / Q000209:etiology; D003967:Diarrhea / Q000209:etiology; D004415:Dyspepsia / Q000453:epidemiology; D005260:Female; D005356:Fibromyalgia / Q000453:epidemiology; D005764:Gastroesophageal Reflux / Q000453:epidemiology; D006261:Headache / Q000453:epidemiology; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales