Background and aim: Twenty-percentage of acute pancreatitis (AP) cases is labeled as idiopathic. Cannabis remains the most frequently used illicit drug in the world. The aim of this study was to identify the prevalence of cannabis use among all patients with a first episode of AP, particularly in those labeled as idiopathic etiology, and determine any effect on AP severity.
Methods: Retrospective cohort of all consecutive patients admitted with a first episode of AP at a large tertiary referral hospital from 01/2013 through 12/2014. AP was identified by ICD9 code, or lipase ≥ 3 times the upper limit of normal and abdominal pain consistent with AP. Cannabis users (CU) were identified via history or urine toxicology.
Results: Four hundred and sixty patients were included. 54% were men, with a mean age of 48 years (range 17-89 years). Forty-eight patients (10%) were identified as CU. After adjusting for admission SIRS, age, and gender, cannabis use was not found to be an independent risk factor for persistent SIRS, AKI, ARDS, pancreatic necrosis, mortality, ICU admission, length of stay, in-hospital infections, nor recurrent AP. Of note, AKI was least common among non-CU compared to CU (OR 0.4; p = 0.02; CI 0.2-0.9) and non-CU had a higher admission BISAP score (≥ 2) compared to CU (OR 2.5; p = 0.009; CI 1.2-4.9).
Conclusion: This is the largest study to date examining cannabis use in AP. Cannabis use was found across almost all etiologies of AP with a prevalence of 10% (48 cases), and in 9% (9 cases) of so-called idiopathic AP cases in this cohort, which could account as an association for approximately 2% of all AP cases. Cannabis use did not independently impact AP severity or mortality.
Keywords: Acute pancreatitis; Cannabis; Diagnosis; Marijuana; Prevalence.