Reduced thiamine phosphate, but not thiamine diphosphate, in erythrocytes in elderly patients with congestive heart failure treated with furosemide

OBJECTIVES: To measure the concentrations of thiamine and thiamine esters by high-pressure liquid chromatography (HPLC) in elderly patients treated with furosemide for heart failure and in a control group. DESIGN: A cross-sectional study of blood thiamine and thiamine ester concentrations. SUBJECTS: Forty-one patients admitted to hospital for heart failure and 34 elderly living at home. No vitamin supplementation was allowed. RESULTS: Compared with the healthy controls, furosemide-treated patients had significantly reduced whole blood thiamine phosphate (TP; 4.4 +/- 2.2 vs. 7.6 +/- 2.0 nmol L-1) and thiamine diphosphate (TPP; 76 +/- 21.5 vs. 91 +/- 19.8 nmol L-1) (mean +/- SD). When the thiamine concentrations were related to the haemoglobin concentrations, which were reduced in the heart failure patients, the levels of TP (nmol g-1 Hb) were 0.38 +/- 0.26 vs. 0.54 +/- 0.17 (P < 0.0001), and of TPP were 6.35 +/- 1.76 vs. 6.37 +/- 1.29 (P = 0.95). There were no differences in T and TP concentrations in plasma between the two groups. CONCLUSIONS: The elderly patients with heart failure treated with furosemide have not reduced the storage form of thiamine, TPP, but only TP. This change is most likely not an expression of a thiamine deficiency, but rather of an altered metabolism of thiamine, which is not understood at present.