Blood thiamine and its phosphate esters as measured by high-performance liquid chromatography: levels and associations in diabetes mellitus patients with varying degrees of microalbuminuria.

BACKGROUND: Thiamine deficiency has been linked to microvascular complications in patients with diabetes mellitus (DM). In this study, we aim to assess blood and urine thiamine status by high performance liquid chromatography (HPLC) in patients with DM Type 1 and Type 2 (DMT1, DMT2) and to identify associations with markers of incipient nephropathy and kidney dysfunction.

SUBJECTS AND METHODS: A total of 205 subjects (43 DMT1 and 162 DMT2) with and without microalbuminuria and 26 non-diabetic controls were included. Fasting blood samples were collected and anthropometric parameters were measured. Fasting blood, lipid and renal profile were determined routinely. Blood thiamine concentration, its phosphate esters and urine thiamine were quantified using HPLC.

RESULTS: Blood thiamine concentrations (ng 1-1) were decreased by 75.7% and 49.6% in patients with DMT1 and DMT2, respectively [controls (54.8+/-11.4); DMT1 (41.5+/-17.9); DMT2 (27.2+/-12.7), p<0.001]. Among those with normo-albuminuria, urinary excretion of thiamine was significantly increased to 390.1 microg/ml and 1212.4 microg/ml in DMT1 and DMT2 respectively, as compared to controls (326.4 microg/ml). DMT1 and DMT2 patients with micro- albuminuria on the other hand had 2.5- and 3.4-fold increase in urinary excretion of thiamine compared to controls.

CONCLUSION: Low levels of blood thiamine are present in patients with DMT1 and DMT2, and are associated with increased thiamine clearance.