What are we missing when colon preparation is inadequate?

The impact of opiate pain medications and psychoactive drugs on the quality of colon preparation in outpatient colonoscopy

BACKGROUND

Suboptimal colon preparation is a significant barrier to quality colonoscopy. The impact of pharmacologic agents associated with gastrointestinal dysmotility on quality of colon preparation has not been well characterized.

AIMS

Evaluate impact of opiate pain medication and psychoactive medications on colon preparation quality in outpatients undergoing colonoscopy.

METHODS

Outpatients undergoing colonoscopy at a single medical centre during a 6-month period were retrospectively identified. Demographics, clinical characteristics and pharmacy records were extracted from electronic medical records. Colon preparation adequacy was evaluated using a validated composite colon preparation score.

RESULTS

2600 patients (57.3 ± 12.9 years, 57% female) met the inclusion and exclusion criteria. 223 (8.6%) patients were regularly using opioids, 92 antipsychotics, 83 tricyclic antidepressants and 421 non-tricyclic antidepressants. Opioid use was associated with inadequate colon preparation both with low dose (OR = 1.4, 95%CI 1.0-2.1, p = 0.05) and high dose opioid users (OR = 1.7, 95%CI 1.1-2.9, p = 0.039) in a dose dependent manner. Other significant predictors of inadequate colon preparation included use of tricyclics (OR = 1.9, 95%CI 1.1-3.0, p = 0.012), non-tricyclic antidepressants (OR = 1.5, 95%CI 1.1-2.0, p = 0.013), and antipsychotic medications (OR = 2.2, 95%CI 1.4-3.4, p = 0.001).

CONCLUSIONS

Opiate pain medication use independently predicts inadequate quality colon preparation in a dose dependent fashion; furthermore psychoactive medications have even more prominent effects and further potentiates the negative impact of opiates with concurrent use.