A Narrative Review of Adhesive Capsulitis with Diabetes

Background/Objectives: To update the perspectives of the association between diabetes (DM) and adhesive capsulitis (AC). Methods: Our findings were summarized in a narrative review. We searched PubMed, Embase, and Consensus databases, using keywords such as "diabetes", "adhesive capsulitis", and "frozen shoulder", for articles published from January 2015 to June 2024, covering both type 1 and type 2 DM. Results: After compiling relevant articles on DM-related AC published since 2015, we found that most studies show an increased prevalence of AC in DM patients, ranging from 3 to 10 times. A longer duration of DM is a risk factor for AC. Whether T1DM or prolonged insulin use will increase the risk of AC is still controversial. Poor blood sugar control seems to increase the risk of AC. Recent studies also show a correlation between blood sugar levels and the prevalence of AC. Cytokines, such as IL-6, IL-8, TNF-α, VEGF, and AGEs, related to inflammation and fibrosis may contribute to the pathophysiological processes of AC. Conclusions: Recent research findings have revealed new perspectives divergent from past notions, while also presenting some topics worthy of exploration. Due the close relationship between DM and AC, clinicians need to be alert to the presence of AC, especially early stage, in DM cases, and control the blood glucose level to reduce the risk of AC. Further research is still needed to provide better prevention and management for DM patients with AC.