Association between smoking status and inpatient outcomes of acute cholangitis in the United States: a propensity matched analysis

BACKGROUND: Acute cholangitis (AC) is an infection of the biliary tract superimposed on stasis. This study aimed to investigate the effects of smoking on inpatient outcomes of AC. METHODS: We identified primary AC hospitalizations using the National Inpatient Sample database (2017-2020). Using a 1:1 matching method, we created a matched comparison cohort of AC patients who were non-smokers, based on demographics, hospital characteristics and comorbidities. RESULTS: We matched 3960 smoker patients with 3960 non-smoker patients within the AC population. Non-smokers were older than smokers (70 vs. 59 years, P<0.001). Smokers had a stronger association with bile duct calculi (74.37% vs. 69.29%, P<0.001) and other bile duct disorders (clots, parasites, extrinsic compression and other rare disorders) (6.82% vs. 5.05%, P=0.011). No significant difference in inpatient mortality, median length of stay (LOS), or median inpatient cost (MIC) was found between the matched cohorts (P>0.05). However, smoking was associated with higher odds of complications, including sepsis without shock (0.88% vs. 0.51%, P=0.042), sepsis with shock (1.26% vs. 0.51%, P<0.001), biliary pancreatitis (6.57% vs. 4.42%, P<0.001) and myocardial infarction (6.19% vs. 3.54%, P<0.001), as well as a greater need for inpatient endoscopic retrograde cholangiopancreatography (ERCP) (72.85% vs. 63.76%, P<0.001) and early ERCP (50.76% vs. 42.32%, P<0.001) compared to non-smokers. CONCLUSIONS: This study found no difference in mortality, LOS, or MIC in acute cholangitis-related hospitalizations associated with smoking. However, smoking was associated with a higher risk of complications and a greater need for ERCP and early ERCP.