Constipation is not associated with an increased rate of findings on colonoscopy: results from a national endoscopy consortium

Abstract

Background and study aims: There are no definite guidelines regarding colonoscopic evaluation for the indication of constipation, a common gastrointestinal complaint. The aim of our study was to determine the risk of finding significant lesions in patients undergoing colonoscopy for the indication of constipation alone compared with constipation with another indication or average-risk screening.

Patients and methods: A retrospective review of the Clinical Outcomes Research Initiative database was carried out for colonoscopies undertaken between 1 January 2000 and 30 June 2003. A total of 41,775 index colonoscopies performed for the indications of average-risk screening, constipation only or constipation with another indication were identified. Logistic regression analyses were performed for constipation alone versus constipation with another indication, and for constipation alone versus average-risk screening.

Results: Constipation alone did not show any increased risk of significant findings on colonoscopy. Constipation and the presence of another indication, however, had a statistically significant increased risk of a significant finding on colonoscopy. The indication of constipation alone had a lower risk of significant findings on colonoscopy compared with average-risk screening. Variations in the definition of constipation used was a limitation of the study.

Conclusions: Colonoscopy for constipation alone has a lower yield for significant findings compared with average-risk screening and constipation with another indication; hence, colonoscopy should not be done for constipation alone.

Figure 1

Odds ratio (OR) for significant finding on colonoscopy for constipation only versus average-risk screening. Forrest plot depicting logistic regression analysis. CI, confidence interval; ¹VA, Veteran’s Administration. *Other, Asian/Pacific Islander.

Figure 2

Adjusted relative risk (ARR) of significant Endoscopic finding based on demographic factors among different constipation groups (constipation alone or constipation along with anemia, hematochezia, positive FOBT or weight loss). Gender group is further divided based on age groups. Indication of endoscopy included constipation alone or constipation along with another indication. Except for constipation only, the remaining groups are not mutually exclusive. The logistic regression model was adjusted for age, gender, race/ethnicity and setting (Community, University or VA). ¹VA, Veteran’s administration; ²FOBT, Positive fecal occult blood test; ³CI, Confidence interval; ^¶Non-Hispanic; ⁴Other, Asian/Pacific Islander.