Is type 2 diabetes a chronic inflammatory/autoimmune disease?

Area of Science:

• Endocrinology
• Immunology
• Metabolic Diseases

Background:

• Distinguishing Type 1 diabetes (T1DM) from Type 2 diabetes (T2DM) relies on insulin therapy needs and immunologic markers, but overlap exists.
• Islet cell autoimmunity, typical of T1DM, is found in 10-15% of clinically diagnosed T2DM patients, suggesting a misclassified subgroup.
• UK Prospective Diabetes Study (UKPDS) data shows autoantibodies like GAD and ICA predict insulin need in T2DM, similar to childhood diabetes studies.

Discussion:

• The presence of islet cell autoimmunity in T2DM may explain insulin secretion defects and insulin resistance.
• A pronounced acute phase response observed in a subset of T2DM patients is associated with islet cell autoimmunity.
• This autoimmune component in T2DM could affect up to two million Americans, mirroring recent-onset childhood diabetes prevalence.

Key Insights:

• Autoantibodies (GAD, ICA) and inflammatory markers can identify a subgroup of T2DM patients with underlying autoimmunity.
• This autoimmune T2DM subgroup may represent a significant portion of misdiagnosed cases, potentially impacting treatment strategies.
• Early identification of autoimmune T2DM could lead to timely immunomodulatory interventions.

Outlook:

• Public health interest lies in identifying at-risk individuals for accurate diabetes classification.
• Immunomodulatory therapies could be initiated early in diagnosed T2DM patients with autoimmune markers.
• Intervention may delay insulin requirement and reduce long-term hyperglycemia-related complications in this subgroup.