Inadequate management of opioid-induced constipation in European cancer pain patients: results of a real-world, multicentre, observational study ("E-StOIC").

Purpose: The objectives of the study were to determine the prevalence of (uncontrolled) OIC, relevant medications / interventions employed by healthcare professionals, and the additional strategies utilised by patients, amongst European patients with cancer pain.

Methods: This study was a prospective observational study conducted at 24 research sites in ten European countries. Cancer patients receiving opioid analgesics for at least a week were recruited, and asked to complete a questionnaire including background information, single question (Are you constipated?), Rome IV diagnostic criteria for OIC, Bowel Function Index (BFI), and Patient Assessment of Constipation Quality of Life questionnaire (PAC-QOL). Participants were characterised as having / not having OIC on the basis of the Rome IV diagnostic criteria.

Results: 1200 participants completed the study. 59.5% met the Rome IV diagnostic criteria for OIC: only 61.5% that met these criteria self-reported constipation. 72% participants were prescribed a regular conventional laxative / peripherally acting mu-opioid receptor antagonist (PAMORA). However, only 66% took their prescribed laxatives every day. Many participants had utilised other strategies / interventions to manage their OIC. Furthermore, 27% had needed to use suppositories, 26.5% had needed to use an enema, and 8% had had a manual evacuation. The use of PAMORAs, and other novel effective medications, was relatively uncommon.

Conclusion: The results of this study suggest that management in Europe is often inadequate, and this undoubtedly relates to a combination of inadequate assessment, inappropriate treatment, and inadequate reassessment.