Thyroid autoimmunity in children and adolescents with type 1 diabetes: a multicenter survey.
OBJECTIVE
To investigate thyroid autoimmunity in a very large nationwide cohort of children and adolescents with type 1 diabetes.


METHODS
Data were analyzed from 17,749 patients with type 1 diabetes aged 0.1-20 years who were treated in 118 pediatric diabetes centers in Germany and Austria. Antibodies to thyroglobulin (anti-TG) and thyroperoxidase (anti-TPO) were measured and documented at least once in 7,097 patients. A total of 49.5% of these patients were boys, the mean age was 12.4 years (range 0.3-20.0 years), and the mean duration of diabetes was 4.5 years (range 0.0-19.5 years). A titer exceeding 100 units/ml or 1:100 was considered significantly elevated.


RESULTS
In 1,530 patients, thyroid antibody levels were elevated on at least one occasion, whereas 5,567 were antibody-negative during the observation period. Patients with thyroid antibodies were significantly older (P < 0.001), had a longer duration of diabetes (P < 0.001), and developed diabetes later in life (P < 0.001) than those without antibodies. A total of 63% of patients with positive antibodies were girls, compared with 45% of patients without antibodies (P < 0.001). The prevalence of significant thyroid antibody titers increased with increasing age; the highest prevalence was in the 15- to 20-year age group (anti-TPO: 16.9%, P < 0.001; anti-TG: 12.8%, P < 0.001). Thyroid-stimulating hormone (TSH) levels were higher in patients with thyroid autoimmunity (3.34 microU/ml, range 0.0-615.0 microU/ml) than in control subjects (1.84 microU/ml, range 0.0-149.0 microU/ml) (P < 0.001). Even higher TSH levels were observed in patients with both anti-TPO and anti-TG (4.55 microU/ml, range 0.0-197.0 microU/ml).


CONCLUSIONS
Thyroid autoimmunity seems to be particularly common in girls with diabetes during the second decade of life and may be associated with elevated TSH levels, indicating subclinical hypothyroidism.
Kordonouri
Olga
O
Clinic for General Pediatrics, Otto-Heubner Centrum, Charité, Campus Virchow-Klinikum, Humboldt University, Berlin, Germany. olga.kordonouri@charite.de
Klinghammer
Albrecht
A
Lang
Egbert B
EB
Grüters-Kieslich
Annette
A
Grabert
Matthias
M
Holl
Reinhard W
RW
D000293:Adolescent; D000328:Adult; D001827:Body Height; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy / Q000453:epidemiology* / Q000276:immunology*; D006801:Humans; D006943:Hyperglycemia / Q000453:epidemiology / Q000276:immunology; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007223:Infant; D007231:Infant, Newborn; D007328:Insulin / Q000627:therapeutic use; D016036:Seroepidemiologic Studies; D013961:Thyroid Gland / Q000502:physiology; D013967:Thyroiditis, Autoimmune / Q000188:drug therapy / Q000453:epidemiology* / Q000276:immunology*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000627:therapeutic use
D007004:Hypoglycemic Agents; D007328:Insulin; D013972:Thyrotropin; D013974:Thyroxine