Trajectories of Pain Processing in Recurrent Acute and Chronic Pancreatitis: A Longitudinal Quantitative Sensory Testing Study.

backgroundRecurrent acute and chronic pancreatitis are often associated with severe abdominal pain. Notably, the presence and intensity of pain often show little correlation with structural pancreatic changes, suggesting a role for altered peripheral and central pain processing. To investigate these mechanisms, a pancreas-specific quantitative sensory testing protocol (P-QST) has been developed to characterise pain processing. However, how P-QST patterns evolve over time remains unclear.

methodsWe conducted a three-year prospective observational study at two Danish hospitals, enrolling patients with recurrent acute or chronic pancreatitis. Participants underwent annual P-QST assessments and filled in questionnaires focused on clinical pain and life quality. P-QST phenotypes were classified into P-QST subgroups based on established normative criteria: (i) no hyperalgesia, (ii) segmental hyperalgesia, or (iii) widespread hyperalgesia. Changes in P-QST phenotypes were investigated over time, and their associations with patient-reported outcomes were examined.

resultsEighty-four patients were included (35 recurrent acute pancreatitis and 49 chronic pancreatitis). The mean age was 48.8 years, and 71% were male. At baseline, 47 (56%) had no hyperalgesia, 21 (25%) had segmental hyperalgesia, and 16 (19%) had widespread hyperalgesia. P-QST phenotypes changed in 46% of patients within the first year; 23% improved (less hyperalgesia), and 23% worsened (worse hyperalgesia). Patients with worsening hyperalgesia reported greater declines in quality of life and greater increases in pain interference scores than those with stable or improving P-QST phenotypes (all p < 0.03).

conclusionP-QST phenotypes in recurrent acute and chronic pancreatitis are dynamic and associated with pain and quality of life outcomes. SIGNIFICANCE STATEMENT: Pain in recurrent acute pancreatitis and chronic pancreatitis often cannot be explained by structural pancreatic changes, indicating altered pain processing. This prospective three-year study demonstrates that pancreas-specific quantitative sensory testing (P-QST) phenotypes are dynamic rather than stable traits. Importantly, changes in P-QST phenotypes were associated with clinically meaningful changes in pain interference and quality of life. These findings support longitudinal assessment of pain processing and highlight P-QST as a potential tool for phenotyping pain.