HYPERHOMOCYSTEINAEMIA - A COMMON FINDING IN A PSYCHOGERIATRIC POPULATION

Plasma homocysteine concentration is a sensitive marker for cobalamin and folate deficiency. The previously reported high incidence of incre ased plasma homocysteine in psychogeriatric patients and the associati on between reduced concentrations of cobalamin, folate and neuropsychi atric symptoms led to the present study on 741 consecutive psychogeria tric patients. The concentrations of plasma homocysteine correlated si gnificantly with blood folate, serum cobalamin and serum creatinine bo th in demented (n = 295) and in non-demented patients with other psych iatric disorders (n = 215). Plasma homocysteine concentrations were si gnificantly increased in both the demented and the non-demented patien ts, whereas only the demented patients had lower blood folate and seru m creatinine concentrations than 163 control subjects. Almost all of t he different diagnostic groups of demented and nondemented patients ex hibited significantly increased plasma homocysteine concentrations com pared with control subjects. Significantly decreased blood folate conc entrations were mainly found in the different diagnosis groups of deme nted patients. Plasma homocysteine concentrations in both demented and nondemented patients with serum cobalamin and blood folate above the lower 20th percentile of these vitamins in the control subjects were a lso studied. Despite these vitamin concentrations, both groups of pati ents still exhibited significantly higher plasma homocysteine concentr ations than the control subjects, which may indicate an increased freq uency of impaired genetic capacity to metabolize homocysteine in these patients. Patients with either dementia of vascular cause or a histor y of other occlusive arterial disease had a significantly higher plasm a homocysteine concentration than those without a history of vascular disease.