Our rate of OIC is consistent with previously published figures [3–9]. However, we demonstrate for the first time that prophylactic laxatives are prescribed infrequently and unsuccessfully in the inpatient setting. This is consistent with prescribing rates in the outpatient setting [9,25]. Furthermore, we observed a higher rate of constipation in those treated with prophylactic laxatives compared to those that did not receive prophylactic laxatives. Pottegard et al similarly demonstrated an increased rate of constipation in those utilizing laxative therapy [25]. This is likely secondary to providers recommending prophylactic laxatives to those patients most likely to develop constipation. Despite being able to recognize high-risk patients, providers are unable to prevent OIC as little is known regarding optimal laxative strategies. Previous studies comparing treatment regimens for the relief of constipation in the palliative care population have been largely inconclusive [26]. There have been no studies to date comparing different prophylactic laxatives in the inpatient setting.
Future directions for research in this area would ideally take the form of randomized controlled trials investigating efficacy of different prophylactic laxatives in the inpatient setting. These trials would ideally include well-defined patient groups receiving specific narcotics for specific reasons. These studies would be best if powered to assess the effect of narcotic dosage and duration of therapy as well. Alternatively, larger retrospective chart reviews could be performed including narcotic dosage, type, and duration of therapy with a planned logistic regression model attempting to account for likely independent variables.
Conclusion
Our study demonstrates for the first time that prophylactic laxatives are not being prescribed frequently to patients on opioid analgesia in the inpatient general medicine setting. Additionally, while providers seem to be identifying patients at higher risk of constipation, they are still unable to prevent constipation in a high percentage of patients. Further research into this area would be beneficial to prevent this uncomfortable, costly, and preventable complication of opioid analgesia.
Corresponding author: Roger Yu, MD, Mayo Clinic, 200 First St. SW, Rochester, MN 55905, Yu.Roger@mayo.edu.
Funding/support: This research was supported by the Mayo Clinic Return to Work program nurses for data abstraction.
Financial disclosures: None.