Folate testing in hospital inpatients.
Since Canada began fortifying grain products with folic acid in 1998, the rate of folate deficiency in outpatients has decreased substantially. Limited data exist on the prevalence of folate deficiency in Canadian hospital inpatients. The electronic patient record at a large urban academic institution was reviewed for all red blood cell folate and vitamin B12 level tests performed on inpatients between January 1 and December 31, 2010. Chart reviews were performed on patients found to have folate deficiency to determine the indication for folate testing and the etiology of deficiency. There were 2563 red blood cell folate and 3154 vitamin B12 level tests performed in 2010. Of these, only 4 (0.16%) red blood cell folate levels were in the deficient range (<254 nmol/L), compared with 98 (3.1%) and 426 (13.5%) vitamin B12 levels that were in the deficient (<138 pmol/L) and intermediate (138-221 pmol/L) range, respectively. Of the 4 patients with folate deficiency, the etiology appeared to be alcohol abuse in one, a malabsorption syndrome in the second, decreased oral intake due to schizophrenia in the third, with the final low folate level appearing to be spurious. At a cost of $12.54 per test, $32,140 could be saved each year at this institution if red blood cell folate testing on inpatients was restricted. Folate deficiency in inpatients is nearly nonexistent, while an appreciable number of patients have low/intermediate vitamin B12 levels. Significant savings could be achieved by eliminating folate testing on inpatients.