Plasma homocysteine is a sensitive marker for tissue deficiency of both cobalamines and folates in a psychogeriatric population

The concentration of blood folates was decreased and the concentration of p lasma homocysteine was increased in a psychogeriatric population, whereas t he concentrations of methylmalonic acid or serum cobalamins were not change d compared with healthy subjects, The highest frequency of abnormal values was shown by plasma homocysteine concentration, which was increased in 88 o f 168 patients, In 29 of these 88 patients increased concentration of plasm a homocysteine could possibly be attributed to tissue cobalamin deficiency, One patient had only a lowered concentration of blood folate, Thirteen pat ients had elevated concentrations of serum creatinine which could explain i ncreased plasma homocysteine concentration, Even if the remaining patients (n = 45) had normal vitamin levels in circulation, the increased plasma hom ocysteine concentration in most cases must be attributed to tissue deficien cy of cobalamins and/or folates, Thus, many patients with increased plasma homocysteine concentrations need further vitamin supplementation despite th eir normal vitamin levels in serum and blood, Copyright (C) 1999 S. Karger AG, Basel.