Endocrine Abstracts

Subclinical thyroid dysfunction associated with a poor lipid profile and cardiac dysfunction. Patients with DM2 suffer from a greater risk of vascular disease, often in association dislipidemia. Thyroid dysfunction might either contribute to these factors or make them worse.

Objective: To assess the prevalence of thyroid dysfunction among patients with diabetes and the relationship between that condition the control of diabetes and lipid profile.

Methods: Retrospective study of files of DM2 patients who had been treated in the diabetes clinic of an endocrine department since 1999. 499 such patients were observed during this period. Mean age was 62.6 years, 58% were males. Data analysis included: anthropometric characteristics, duration of diabetes, HbA1c, lipids and thyroid function. Continuous variables were compared across groups by Student's t-test and frequencies by the chi-square test. All statistical tests were carried out two-sided, at a 5% level of significance.

Results: Thyroid function was found in 298 patients. 38 (12.7%) suffered from thyroid dysfunction, 10,7% had hypothyroidism (68.7% subclinical) and 2% had hyperthyroidism. In 31 cases (10.4%) the diagnosis was performed 'de novo'. The lipid profile of patients with thyroid dysfunction did not differ significantly from that of diabetics patients with euthyroidism. Nor did HbA1c levels, duration of diabetes or length of treatment differ significantly from one group to another. Thyroid disease was more prevalent among female and older patients.

Conclusions: There are few studies on DM2 and thyroid dysfunction; they seem to indicate a higher occurrence of thyroid dysfunction among diabetics when compared with the general population. Our work led us to the same conclusion (12.7% of diabetics had thyroid dysfunction). Hypothyroidism was the most common type of dysfunction. We found no significant differences between these patients' lipid profile and that of euthyroid patients with DM2. Unlike other studies, we did not find any relationship between metabolic control and thyroid function. The high percentage of patients whose thyroid dysfunction was diagnosed 'de novo' may justify routine thyroid function assessments of DM2.