[Photoplethysmographic evaluation of microcirculation in patients with overt and latent hyperthyroidism or hypothyroidism].

Alterations in the finger microcirculation in patients with disturbed function of the thyroid gland was evaluated with planimetric photoplethysmography. One-hundred forty-one patients with disturbed thyroid function (31 overt hyperthyreoidism, 10 latent hyperthyreoidism, 79 overt hypothyreoidism, 22 latent hypothyroidism) and 30 healthy individuals were investigated. Serum free thyroxine and thyreotropine level were determined in all investigated subjects. The systolic-diastolic index (SDI) was measured in all individuals with photopletysmography. A decrease in SDI was found in the patients with hyperthyroidism (overt 0.121; latent 0.158) and an inverse in SDI was shown in hypothyroid patients (overt 0.617; latent 0.471) was compared with the controls (0.345). SDI correlated with serum free thyroxine and thyreotropine levels and clinical symptoms.