Acute and chronic pancreatitis, active component, U.S. Armed Forces, 2004-2018.

Pancreatitis is an inflammatory disease of the pancreas resulting from the premature activation of digestive enzymes within the pancreas. Pancreatitis occurs in both acute and chronic forms. During 2004-2018, a total of 6,471 U.S. active component service members received incident diagnoses of acute pancreatitis (AP), for a crude overall incidence rate of 31.8 per 100,000 person- years (p-yrs). Compared to their respective counterparts, overall rates of AP diagnoses were highest among females, those in older age groups, non-Hispanic blacks, Army members, and those working in healthcare occupations. Crude annual rates of AP diagnoses increased by 25.5% over the 15-year period; this trend was driven largely by a rise in outpatient rates. Of the total incident cases of AP, 9.0% received a subsequent incident diagnosis of chronic pancreatitis (CP) during the surveillance period. Between 2004 and 2018, the crude overall incidence rate of CP was 4.4 per 100,000 p-yrs. Patterns of overall rates of CP by demographic and military characteristics were generally similar to those for AP. Crude annual rates of CP fluctuated between 3.7 per 100,000 p-yrs and 5.7 per 100,000 p-yrs during the surveillance period, with no pronounced overall trend over time. To inform preventive and therapeutic strategies, continued research is needed to understand the factors that increase risk of progression from AP to CP and the importance of the interaction between genetic and environmental factors in this transition.