Assessment of Primary Hemostasis by Platelet Function Analyzer-100 and its Relation with TSH and FT₄ Levels in Newly Diagnosed Overt and Subclinical Hypothyroid Patients

Various abnormalities of coagulation such as primary hemostasis, secondary hemostasis and fibrinolysis have been reported in patients with subclinical and overt hypothyroidism. Platelets are major elements of primary hemostasis and endothelial repair. Platelet size, shape and number are the determinant of platelet function. The objective of this study was to assess primary hemostasis by PFA-100 (Platelet Function Analyzer-100) and its relation with TSH and FT₄ levels in newly diagnosed overt and subclinical hypothyroid patients. This cross-sectional study was conducted in the Department of Physiology, Dhaka Medical College, Bangladesh from January 2016 to December 2016. Twenty overt and 20 subclinical hypothyroid patients with age ranging from 18 to 55 years were selected as study group and twenty age and sex matched healthy subjects were considered as control group. Patients were selected from Outpatients Department of Endocrinology and Nuclear Medicine & Allied Sciences of Dhaka Medical College Hospital, Dhaka on the basis of exclusion and inclusion criteria. For assessment of primary hemostasis, PFA-100 was analyzed by SIEMENS-INNOVANCE-PFA-200. For statistical analysis Unpaired Student's 't' test, Chi square test and Pearson's correlation co-efficient (r) test were performed. PFA-100 was significantly higher (p<0.001) in overt and subclinical hypothyroid patients as compared to healthy adult subjects. In overt and subclinical hypothyroidism using PFA-100, we found that the existence of a hypocoagulable state is due to a defect in primary hemostasis. Moreover, PFA-100 may replace the in-vivo bleeding time as a screening test for primary hemostasis in routine clinical practice.