OBJECTIVE: To investigate the prevalence of thyroid
dysfunction and autoimmunity in type 2 diabetic patients.
METHODS: The study was conducted at the National Center
for Diabetes, Endocrinology and Genetics, Jordan
University Hospital, Amman, Jordan, between March
2000 and September 2000. A group of 908 type 2 diabetic patients
(T2DM) were recruited in the study and underwent investigations
for thyroid functions; free thyroxine (FT4), free tri-iodothyronine
(FT3) and thyroid stimulating hormone (TSH). Six hundred had
performed thyroid autoantibodies, thyroid peroxidase antibodies
(TPOab) or antimicrosomal antibodies (AMA) and thyroglobulin
antibodies (Tgab). They were compared with 304 non-diabetics, of
those 282 had performed thyroid antibodies.
RESULTS: Fifty-three (5.9%) of diabetic patients were
known to have thyroid disease. As a direct result of screening,
new thyroid disease cases were diagnosed in 6.6% of the
patients. Thus, the overall prevalence of thyroid disease was
found to be 12.5%. The most common was subclinical
hypothyroidism (4.1%). In the control group, the prevalence of
thyroid disease was 6.6%. The most common was subclinical
hypothyroidism (5%). There was a significant difference between
diabetics and control subjects p=0.0064. Positive TPOab was
found in 8.3% of T2DM patients (N=600) versus 10.3% in the
control group (N=282) p=0.412. Positivity for both TPOab and
Tgab was found to be 2.5% of T2DM versus 6% of the control
CONCLUSION: This study suggests that diabetic patients
should be screened for asymptomatic thyroid dysfunction.
National Center of Diabetes, Endocrinology and Genetics,
Jordan University of Science and Technology,
School of Medicine, Irbid, Jordan.