Various abnormalities of coagulation may occur in patients with thyroid disorders and may range from subclinical laboratory abnormalities to clinically significant disturbances of coagulation. Tissue factor pathway inhibitor (TFPI) is a newly determined potent inhibitor of tissue factor dependent coagulation system. TFPI changes in various thyroid disorders has not been evaluated yet. In this study we have evaluated total TFPI (tTFPI), free TFPI (fTFPI), tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1 antigen (PAI-1) levels before treatment and after euthyroidism achieved in age and sex matched hyperthyroid (n: 10), hypothyroid (n: 10) and subclinical hypothyroid (n: 10) patients and compared the data with age and sex matched control subjects (n: 16). Plasma tTFPI and free-form TFPI antigen concentrations were measured using a sndwich enzyme immunoassy (EIA) kits commercially available. Measurement of tPA and PAI-1 Ag used an enzyme-linked immunosorbent assay. fT3, fT4, TSH levels were determined by non isotopic automated immunochemiluminometric system (ACS: 180, Chiron Diagnostics, UK). For TSH determination a third generation assay was used. In hyperthyroid status mean fTFPI level and PAI-1 levels were significantly higher in hyperthyroid patients compared to control subjects (p<0,05). There was no significant difference in tTFPI and tPA levels in basal status in huperthyroid patients (p>0,05). When hyperthyroid patiens were reevaluated in euthyroid status, t-TFPI, f-TFPI, tPAand PAI-1 levels were found to be significantly decreased (p<0,05). In hypothyroid and subclinical hypothyroid patients there was no significant difference in none of these coagulation parameters neither in basal status, nor in euthyroid status. When cumulative data was analaysed for correlations, fTFPI and tPA were significantly positively correlated with fT3, fT4, age, and negatively correlated with logarithmic value of TSH. In addition there was a significant positive correlation between fTFPI and tPA (p<0,05). These data suggest that fTFPI and PAI-1 levels were significantly effected especially in hyperthyroid state.
08 - 11 Apr 2002
British Endocrine Societies