Factors affecting glycemic control in diabetes mellitus complicated by autoimmune pancreatitis

AIMS/INTRODUCTION: To investigate factors influencing glycemic control in diabetes mellitus complicated by autoimmune pancreatitis. MATERIALS AND METHODS: This retrospective cohort study investigated 33 patients with diabetes mellitus complicated by autoimmune pancreatitis who had received steroid therapy at Toranomon Hospital between January 1, 2011, and December 31, 2020. The course of glycemic control at 12 months after starting steroids was classified into three groups: Improved, Unchanged, or Worsened. Factors affecting these groups were investigated. Furthermore, we created two scores: (1) time of diabetes mellitus onset and baseline body mass index; (2) time of diabetes mellitus onset and baseline C‐peptide index. Diabetes mellitus occurring at the same time as autoimmune pancreatitis, body mass index ≥22 kg/m(2), and C‐peptide index ≥1.1 were each worth 1 point. Scores were summed and totals of 0–2 were compared between groups. RESULTS: Ten patients were in the Improved group, 10 were in the Unchanged group, and 13 were in the Worsened group. The baseline body mass index and baseline C‐peptide index were lower in the Worsened group than in the Improved group (P < 0.05 each). In addition, the scores were lower in the Worsened group than in the other groups (P < 0.05). CONCLUSIONS: Patients with a lower baseline body mass index and a decreased baseline C‐peptide index may experience worse glycemic control on steroid therapy.