Endocrine Abstracts

Aim: Mean platelet volume (MPV) is considered a new indicator of atherosclerosis. Activated platelets and subclinical inflammation predispose to create for atherosclerotic heart disease. Larger platelets are metabolically more active than smaller ones and have more protrombotic potential. We have recently demonstrated that MPV levels in Hashimoto’s patients tend to be higher than healthy controls even if in euthyroid state. In present study we aimed to investigate a relationship between MPV and autoimmune thyroid disease.

Materials and method: patients with Hashimoto thyroiditis (HASH) (58 euthroid Hashimoto thyroiditis (EHASH) (mean age 43.4±12.4 year)) and 42 hypothyroid (HPHASH) (mean age 46.7±15.5 year)) and 81 patients with Graves disease (GD) (mean age 38.8±13.5 year) who referred our endocrinology outpatient clinic due to high thyroid autoantibodies as antithyroid peroksidase (Anti-TPO) and/or antithyroglobuline (Anti-Tg) and/or TSH receptor antibody were included in the study. 57 (age-matched 46.4±11.6 year) euthyroid control subjects were taken into the study. All study population were evaluated by hormonal and platelet parameters.

Results: Serum Anti-TPO levels in all study groups (EHASH, HPHASH, GD) were significantly higher than those control subjects (P=0.01, P=0.0001, P=0.0001 respectively). The MPV in patients with EHASH, HPHASH, GD were also found significantly higher than control group (P=0.046, P=0.044, P=0.002 respectively). No statistically significant differences were found between the other parameters such as the platelet count, platelet distribution width and plateletcrit. We found that MPV increased independently of presence of age, sex and TSH in chronic autoimmune thyroid diseases (β=0.074, P=0.007). There was a significant correlation between MPV and anti-TPO levels (r=0.145, P=0.027).

Discussion: Our findings suggest that change of autoimmunity in thyroid gland in patients with chronic autoimmune disease may be effect on MPV level as well as tend to create cardiovascular risk because of large platelets have more metabolically active.