Association between chronic pancreatitis and pyogenic liver abscess: a nationwide population study.

Background: The relationship between chronic pancreatitis (CP) and subsequent pyogenic liver abscess (PLA) is not well understood.
Methods: We investigated the risk of PLA in patients with CP using inpatient claims data from the Taiwan National Health Insurance Program for the period 2000-2010. We identified 17,810 patients with chronic pancreatitis (CP group) and 71,240 patients without CP (non-CP group). Both cohorts were followed until a diagnosis of PLA, until they were censored from the study because of loss to follow-up, death, or termination of insurance, or until the study cut-off date of 31 December 2011. Incidence and risk factors for development of PLA, and the effects of comorbidities, were assessed.
Results: The incidence of PLA in the CP group was 12.9 times that in the non-CP group (38.3 vs. 2.89 events per 1000 person-years; 95% confidence interval [CI], 10.5-15.8). After adjusting for age, sex, and the comorbidities of hypertension, diabetes, hyperlipidemia, cerebral vascular accident, cirrhosis, heart failure, chronic obstructive pulmonary disease, chronic kidney disease, cancer, alcoholism, other diseases of the pancreas, cholecystitis, and cholelithiasis and other disorders of the biliary tract and endoscopic insertion of stent (tube) into the bile duct, the risk of PLA remained higher among CP patients than among the comparison cohort (adjusted hazard ratio, 6.40; 95% CI, 4.83-8.49). CP patients with five or more comorbidities had a significantly higher risk of PLA (adjusted hazard ratio, 24.9; 95% CI, 18.3-33.8).
Conclusion: CP was associated with increased risk of subsequent PLA. The risk of PLA was higher in patients with five or more comorbidities.