title: Opioid-induced constipation in patients with chronic noncancer pain in the USA, Canada, Germany, and the UK: descriptive analysis of baseline patient-reported outcomes and retrospective chart review.
abstract: BACKGROUND
  The characteristics of patients who suffer from noncancer pain and opioid-induced constipation are not well understood.
  
  
  METHODS
  Cross-sectional patient survey and chart review data from the baseline assessment of an ongoing longitudinal study in the USA, Canada, Germany, and the UK were evaluated via descriptive statistics. Participants had confirmation of daily opioid therapy ≥30 mg for ≥4 weeks and self-reported opioid-induced constipation. Response to laxatives was defined by classifying participants into categories of laxative use and evaluating the prevalence of inadequate response to one laxative agent and two or more agents from at least two different laxative classes. Outcomes included the Patient Assessment of Constipation-Symptoms, Work Productivity and Activity Impairment Questionnaire-Specific Health Problem, EuroQOL 5 Dimensions, and Global Assessment of Treatment Benefit, Satisfaction, and Willingness to Continue.
  
  
  RESULTS
  Patients reported a mean of 1.4 bowel movements not preceded by laxatives and 3.7 bowel movements with laxative use per week; 83% wanted at least one bowel movement per day. Most commonly reported on Patient Assessment of Constipation-Symptoms were straining/squeezing to pass bowel movements (83%), bowel movements too hard (75%), flatulence (69%), and bloating (69%). Eighty-four percent were taking natural or behavioral therapies; 60% were taking at least one over-the-counter laxative; and 19% were taking at least one prescription laxative. Prevalence of inadequate response to one laxative agent was 94%; inadequate response to two or more agents from at least two different laxative classes was 27%. Mean Work Productivity and Activity Impairment Questionnaire-Specific Health Problem values for percent work time missed, percent impairment while working, and percent activity impairment were 9%, 32% (equivalent of 14 hours of lost productivity per week), and 38%. Mean EuroQOL 5 Dimensions index and visual analog scale scores were 0.49 and 50.6, respectively. Forty-four percent reported being satisfied with their treatment for constipation.
  
  
  CONCLUSIONS
  Patients treated with opioids for noncancer pain commonly endure constipation symptoms that limit their work productivity and overall health-related quality of life while adhering to treatments that provide little relief. Further research is needed to identify more efficacious constipation therapies for this patient population.
authors.affiliation: Evidera, Bethesda, MD, USA.
authors.forename: Karin S
authors.initials: KS
authors.lastname: Coyne
authors.affiliation: AstraZeneca, Wilmington, DE, USA.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: LoCasale
authors.affiliation: AstraZeneca, Wilmington, DE, USA.
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Datto
authors.affiliation: Evidera, Bethesda, MD, USA.
authors.forename: Chris C
authors.initials: CC
authors.lastname: Sexton
authors.affiliation: UBC: an Express Scripts Company, Montreal, QC, Canada.
authors.forename: Karen
authors.initials: K
authors.lastname: Yeomans
authors.affiliation: University Hospital Gasthuisberg, Leuven, Belgium.
authors.forename: Jan
authors.initials: J
authors.lastname: Tack
keywords: constipation; laxatives; opioid; pain; quality of life