The impact of cannabis use disorder on urologic oncologic surgery morbidity, length of stay, and inpatient cost: analysis of the National Inpatient Sample from 2003 to 2014.

PURPOSE: This study examined the impact of cannabis use disorder (CUD) on inpatient morbidity, length of stay (LOS), and inpatient cost (IC) of patients undergoing urologic oncologic surgery.

METHODS: The National Inpatient Sample (NIS) from 2003 to 2014 was analyzed for patients undergoing prostatectomy, nephrectomy, or cystectomy (n = 1,612,743). CUD was identified using ICD-9 codes. Complex-survey procedures were used to compare patients with and without CUD. Inpatient major complications, high LOS (4th quartile), and high IC (4th quartile) were examined as endpoints. Univariable and multivariable analysis (MVA) were performed to compare groups.

RESULTS: The incidence of CUD increased from 51 per 100,000 admissions in 2003 to 383 per 100,000 in 2014 (p < 0.001). Overall, 3,503 admissions had CUD. Patients with CUD were more frequently younger (50 vs. 61), male (86% vs. 78.4%), Black (21.7% vs. 9.2%), and had 1st quartile income (36.1% vs. 20.6%); all p  0.05). However, CUD patients had higher LOS (3 vs. 2 days; p < 0.001) and IC ($15,609 vs. $12,415; p < 0.001). On MVA, CUD was not an independent predictor of major complications (p = 0.6). Conversely, CUD was associated with high LOS (odds ratio (OR) 1.31; 95% CI 1.08-1.59) and high IC (OR 1.33; 95% CI 1.12-1.59), both p < 0.01.

CONCLUSION: The incidence of CUD at the time of urologic oncologic surgery is increasing. Future research should look into the cause of our observed phenomena and how to decrease LOS and IC in CUD patients.