Endocrine Abstracts

Introduction: Metabolic syndrome is a multifactorial disease with multiple risk factors that arises from insulin resistance accompanying abnormal adipose deposition and function, increasing the risk of type 2 diabetes, one of the most common endocrine pathologies. Abundant evidence suggests an association between TSH levels, insulin resistance and some markers of the metabolic syndrome, without foreseeing the kind of this link. The aim of our study was to search if there was a link between type 2 diabetes with metabolic syndrome and hypothyroidism, and to explore the markers that are specially correlated with thyroid status.

Materials and methods: Retrospective study including 100 patients with type 2 diabetes showing criteria of metabolic syndrome, carried within the diabetology department ‘A‘ of the National Institute of Nutrition in Tunis.

Results: 70% of patients had a normal thyroid balance (euthyroid group (G0)) and 30% presented a clinical hypothyroidism (hypothyroid group (G1)). The average age in G0 was 57,8 years compared to 60,8 years in G1 (P=NS). All G1 patients were female (100%) compared to 82% in G0 (P=0,01). Median diabetes duration was 9,78 years in G0 compared to 11,76 years in G1 (P=NS). 51,43% of patients were on insulin in G0 vs 66,66% in G1 (P=NS). The average BMI of G0 patients was 35,9 kg/m² compared to 36,48 kg/m² in G1 (P=NS). Mean fasting blood glucose was significantly higher in G1 than G0 (12,19 mmol/l vs 10,36 mmol/l; P=0,04). The hypothyroid patients had more often low levels of HDLcholesterol and high levels of triglycerides (respectively 60% vs 57,14% in G0; P=NS and 30% vs 28,57% in G0; P=NS). Hypercholesterolemia was significantly more common in G1 than G0 (63,33% vs 25,71%; P=0,0003). The occurrence of cardiovascular events was observed in 11,43% of patients in G0 compared to 6,66% in G1 (P=NS). Thyroid status didn’t have any influence on blood pressure control (mean systolic and diastolic blood pressures were 137 mmHg and 79 mmHg, respectively in both groups).

Conclusion: The prevalence of hypothyroidism among our patients with type 2 diabetes was much higher than in the common population. Our hypothyroid patients had significantly higher fasting blood glucose levels and were more likely to be treated with insulin and to have low levels of HDLcholesterol and high levels of triglycerides. The recommendation for systematic exploration of thyroid status in patients with type 2 diabetes with metabolic syndrome requires larger-scale studies.