Furosemide-related thiamine deficiency in hospitalized hypervolemic patients with renal failure and heart failure.

Background: We aimed to describe the thiamine status in hospitalized hypervolemic heart failure (HF) and/or renal failure (RF) patients treated with furosemide and to investigate whether there was a difference in furosemide-related thiamine deficiency between patients with RF and HF.Methods: Patients who were diagnosed as hypervolemia and treated with intravenous furosemide (at least 40 mg/day) were included in this prospective observational study. Whole blood thiamine concentrations were measured 3 times during hospital follow-up of patients.Results: We evaluated 61 hospitalized hypervolemic patients, of which 22 (36%) were men and 39 (64%) were women, with a mean age of 69.00 & PLUSMN; 10.39 (45-90) years. The baseline and post-hospital admission days 2 and 4 mean thiamine levels were 51.71 & PLUSMN; 20.66 ng/ml, 47.64 & PLUSMN; 15.43 ng/ml and 43.78 & PLUSMN; 16.20 ng/ml, respectively. Thiamine levels of the hyperv-olemic patients decreased significantly during the hospital stay while furosemide treatment was continuing (p = 0.029). There was a significant decrease in thiamine levels in patients who had HF (p = 0.026) and also, thiamine was significantly lower in HF patients who had previously used oral furosemide before hospitalization. However, these findings were not present in patients with RF.Conclusions: Thiamine substantially decreases in most hypervolemic patients receiving intravenous furosemide treatment during the hospital stay. Thiamine levels were signifi-cantly decreased with furosemide treatment in especially HF patients, but the decrease in thiamine levels did not detected at the same rate in RF patients. Diuretic-induced thiamine loss may be less likely in RF patients, probably due to a reduction in excretion.& COPY; 2021 Sociedad Espa n & SIM;ola de Nefrologi & PRIME;a. Published by Elsevier Espa n & SIM;a, S.L.U. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/ by-nc-nd/4.0/)