Chronic constipation not associated with colorectal cancer, study finds

Sweden: A population study by Dr. Kyle Staller and the team revealed that chronic constipation is not associated with later colorectal cancer (CRC). The findings of the study are published in the journal Clinical Gastroenterology and Hepatology.

In India, the annual incidence rates (AARs) for colon cancer and rectal cancer in men are 4.4 and 4.1 per 100000, and colon cancer in women is 3.9 per 100000. Prolonged colon transit times are known to increase the contact time between potential carcinogens in the stool and the colonic mucosa. previous studies have reported conflicting results connecting chronic constipation with the risk of colorectal cancer (CRC).

Dr. Staller and the team aimed to assess the association between chronic constipation and later CRC in a nationwide case-control study. 

The researchers identified 41,299 CRC cases by colorectal biopsy in Sweden between July 2007 and December 2016 and matched them to 203,181 age- and sex-matched controls from the general population. They compared odds of earlier chronic constipation (defined as ≥2 laxative prescriptions in the Prescribed Drug Register with ≥6 months between first-last prescription) between CRC cases and controls using logistic regression. 

In separate analyses, we compared odds of earlier constipation between CRC cases and sibling comparators, but also examined the earlier risk of having an inpatient/outpatient specialty diagnosis of chronic constipation prior to CRC.

 A total of 3,943 patients with CRC met the study criteria for chronic constipation prior to CRC.

The results of the study were

• The crude proportion of chronic constipation in CRC patients was 9.5% compared to 8.8% in controls.

• After multivariable adjustment, there was a modest association between chronic constipation and later CRC (OR=1.10) that vanished using sibling comparators to control for residual confounding (OR=1.04).

• In a sensitivity analysis of 126,650 CRC patients diagnosed 1989-2016, we found no association with earlier chronic constipation diagnosed in inpatient/outpatient specialty clinics (OR=0.88).

Dr. Staller and the team concluded that "In a nationwide case-control study, chronic constipation was not associated with later CRC."

Reference:

DOI:https://doi.org/10.1016/j.cgh.2021.10.024