Introduction

Excessive alcohol consumption is a significant global health concern. Alcohol-related liver disease (ALD) and pancreatitis are two common digestive diseases caused by alcohol. The coexistence of ALD with acute or chronic pancreatitis is common, but with wide prevalence estimates of pancreatitis ranging from 1.4% to 70% in alcohol-related cirrhosis. Due to high variability, a better understanding of the overlap between these diseases is necessary. This nationwide study aims to estimate the incidence of acute pancreatitis (AP) in patients with ALD compared to the general population and identify risk factors for developing AP.

Aims & Methods

This was a nationwide population-based cohort study using data from the Swedish National Patient Register on 37,062 patients with ALD from 1969 to 2020. Patients were matched for sex, age, and municipality with 352,931 reference individuals from the general population. The diagnosis of AP and mortality data were derived from the National Patient Register and the Cause of Death Register, respectively. Logistic regression was employed to estimate the risk of ever having pancreatitis (either acute or chronic) at or prior to ALD diagnosis, and Cox regression was used to estimate rates for hospitalization related to AP after ALD diagnosis.

Results

A total of 389,993 persons were included in the study (median age at entry, interquartile range [IQR], 59 [56–67]; 72.1% male). Of patients with ALD, 7% have experienced at least one episode of pancreatitis before being diagnosed with ALD, which corresponded to 9-fold higher odds of pancreatitis (either acute or chronic) in ALD than in controls. During follow-up, 1,049 patients with ALD developed AP (4.3/1000 person-years) compared with 3,979 reference individuals (0.8/1000 person-years). The 10-year cumulative incidence of AP was 2.7% (95%CI=2.5–2.8) for patients with ALD and 0.6% [95%CI=0.58–0.63) for reference individuals. This corresponded to an adjusted HR of 6.3 (95%CI=5.8–6.9). The rate of AP was highest within the first year after ALD diagnosis (aHR 13.0, 95%CI=10.6–15.9) and was thereafter decreasing during follow up, but was always higher than in reference individuals, e.g., after 10 years (aHR 3.1, 95%CI=2.5–3.8). After excluding patients with gallstone related AP, the results did not change materially. Overall mortality was 74.7% in ALD comparing to 43.1% in the general population. Younger age, male sex, history of alcohol and tobacco consumption were independent risk factors for developing AP in ALD. In particular, drinking after ALD diagnosis was strongly associated with risk of future AP (aHR 8.6, 95%CI=6.7–11.2).

Conclusion

ALD diagnosis is associated with 9-fold increased odds of prior history of pancreatitis compared to the general population. The rate of AP following a diagnosis of ALD is 6-fold higher than in the general population, however only around 2.7% of patients with ALD develop AP within ten years. We identified possible risk factors that could be of clinical interest when trying to estimate AP risk in patients with ALD.