Thyroid autoimmunity in Type 1 diabetes: systematic review and meta-analysis

Area of Science:

• Endocrinology
• Metabolic Disorders
• Autoimmune Diseases

Background:

• Type 1 diabetes (T1D) is an autoimmune condition characterized by pancreatic beta-cell destruction.
• Individuals with T1D have an increased predisposition to other autoimmune disorders, notably thyroid autoimmunity.
• Thyroid dysfunction, including autoimmune thyroid disease, is a common comorbidity in T1D.

Purpose of the Study:

• To systematically review the incidence of thyroid autoimmunity and dysfunction in individuals with T1D.
• To evaluate the existing evidence for screening protocols for thyroid autoimmunity and dysfunction in T1D.
• To assess the association between thyroid autoimmunity and dysfunction and the cost-effectiveness of screening.

Main Methods:

• Systematic review and meta-analysis of prospective cohort studies.
• Inclusion criteria focused on screening for thyroid autoimmunity and/or dysfunction in T1D patients.
• Data synthesis using random effects models for meta-analysis.

Main Results:

• 14 studies involving 2972 young people and 789 adults with T1D were analyzed.
• Incidence rates for thyroid dysfunction varied widely (27-246 per 10,000 patient-years).
• Thyroid autoimmunity incidence ranged from 13 to 326 per 10,000 patient-years; risk of dysfunction was 25 times higher with autoimmunity, particularly in children.

Conclusions:

• There is a substantially elevated risk of thyroid dysfunction in individuals with T1D and co-existing thyroid autoimmunity.
• The optimal screening strategy (method and frequency) for thyroid dysfunction in T1D cannot be established from current data.
• Further research is needed to determine if screening T1D patients for thyroid dysfunction improves clinical outcomes.