Effect of Therapy with Vitamin B₁₂ and Folic Acid on Elderly Patients with Low Concentrations of Serum Vitamin B₁₂ or Erythrocyte Folate but Normal Blood Counts

Abstract

To help understand the haematological significance of the low concentrations of serum vitamin B₁₂ and erythrocyte folate occurring in elderly patients, 17 acute admissions to a geriatric unit with a low concentration of serum vitamin B₁₂ or erythrocyte folate but a normal blood count were treated with vitamin B₁₂ and folic acid for 3 months. Bone marrow deoxyuridine supression was abnormal in 3 of these 17 patients, 2 of whom also had megaloblastic change in the marrow. With treatment, the MCV fell in 13 of the 17, and the average MCV fell from 90.5 to 87.9 fl (p = 0.007), but the mean Hb did not change. Ten untreated similar patients showed no change in their MCV over the same period, but the mean Hb fell from 14.0 to 13.1 g/dl (p = 0.04). Thus the low concentrations of serum vitamin B₁₂ or erythrocyte folate found in approximately a quarter of acutely admitted elderly patients may indicate true tissue deficiency of these vitamins, even when the blood count is normal.

AGE-related differences in the hematological profile of Andalusian broodmares of Carthusian strain

“…This change of MCV with ageing has also been reported in elderly human patients with low concentrations of serum vitamin B12 or erythrocyte folate but a normal blood count (Matthews et al, 1988). These patients were treated with vitamin B12 and folic acid for three months and as a consequence, MCV decreased.…”

Bound vitamin B12 absorption in patients with low serum B12 levels

“…Most lacked hematological or neurological evidence of B , deficiency and resembled patients with gastritis and low serum B,, [18][19] or latent pernicious anemia [20], some of whom remained stable for years despite decreased free B,, absorption. It should also be noted that two of this group had megaloblastic blood findings that responded to sonable assumption that tissue vitamin B deficiency develops as a consequence of defective vitamin B,, absorption, although decreased dietary intake may be contributory [34,35], it would appear unlikely that a low serum vitamin B,, level with normal absorption of bound B,, in our patients reflects B , ? tissue deficiency.…”

Dietary deficiency of vitamin B12 is associated with low serum cobalamin levels in non‐vegetarians

“…The serum cobalamin was above 75 pmol/l (1.0 percentile) in all but 1 patient. Following a hydroxocobalamin injection, the MCV fell by 5 fl or more in 4 patients [ 3,4,9,101 and the RBC rose by 6% or more in 4 patients [ 1, 5, 9, lo]. The alcohol consumption of patients 3, 4 and 10 did not change during the follow-up period.…”

“…Dietary deficiency has been suspected previously as a cause for a low serum cobalamin in nonvegetarians, particularly in elderly patients (6,7,8,9) but in none of these series was a formal assessment of intake undertaken.…”

“…Macrocytosis may not be present even when the deoxyuridine suppression test indicates disturbed cobalamin metabolism (1 1). In some patients the response to hydroxocobalamin may be the only supporting evidence of deficiency (9). The degree of fall in MCV and rise in RBC which we have used to indicate tissue cobalamin deficiency is to some extent arbitrary but takes into account known physiological variation and the technical errors associated with automatic cell counters.…”