Low Borderline Levels of Serum Vitamin B12 May Predict Cognitive Decline in Elderly Hip Fracture Patients

The progression from cognitive impairment to dementia is a multifactorial process that involves genetic and environmental factors. Vitamin B12 deficiency can be an important factor in the progress from cognitive decline to dementia.

To examine the relationship between borderline low level of vitamin B12 (≤ 350 pg/ml) and cognitive decline among a group of elderly hip fracture patients.

This retrospective chart review study was conducted in a geriatric rehabilitation ward of a university-affiliated referral hospital. It comprised 91 elderly hip fracture patients. Cognition was assessed by the Mini-Mental State Examination (MMSE) tool. Fasting serum vitamin B12 levels were measured within 24 hours after admission to the rehabilitation ward.

Twenty-two of the patients had vitamin B12 levels ≤ 350 pg/ml. In a multiple linear regression analysis, after adjusting for confounding variables, serum vitamin B12 levels ≤ 350 pg/ml were linked to a higher risk of developing cognitive decline (ß coefficient = -0.28, P = 0.008).

In our study, serum vitamin B12 levels ≤ 350 pg/ml, were independently associated with lower MMSE scores in elderly hip fracture patients. Serum vitamin B12 may assist in identifying patients in the early stages of cognitive decline. This study joins others that have reported on the association of low normal range vitamin B12 blood levels and conditions like dementia, falls, fractures and frailty. We suggest a reexamination of what is currently considered as the normal range of vitamin B12 in the elderly.