Inappropriate Drug Use in Elderly Patients is Associated with Prolonged Hospital Stay and Increased Postoperative Mortality After Colorectal Cancer Surgery: a Population-based Study

Aim: The study aimed to investigate whether continuing potentially inappropriate medication (PIM) is associated with length of hospital stay (LOS) and postoperative mortality in elderly people undergoing colorectal cancer surgery.

Method: The Swedish National Colorectal Cancer Register and the Swedish Prescribed Drug Register provided matched data on 7279 patients aged 75 years or more who had undergone bowel resection for colorectal cancer between 2007 and 2010. Patients were divided into two groups depending on whether or not they were taking PIM at the time of surgery. The primary efficacy variables were the LOS and 30-day postoperative mortality.

Results: Of the 7279 patients, 22.5% (1641) of the patients were exposed to at least one PIM and the total number of drugs taken in this group was six, compared with three in the non-PIM group (P < 0.001). Postoperative mortality was higher in the PIM group (7.1% vs 4.5%, P < 0.001), and LOS was longer (10 days vs 9, P = 0.001). When adjusted for independent predictors, the differences in LOS (odds ratio 1.14; 95% confidence interval 1.00-1.29, P = 0.046) and postoperative mortality (odds ratio 1.43; 95% confidence interval 1.11-1.85, P = 0.006) remained significant.

Conclusion: The use of PIM prior to surgery is associated with increased postoperative mortality and prolonged hospital stay. Although no causal relationship is proved, the results add a further aspect to preoperative optimization of elderly patients about to have major colorectal surgery.