A study on estimating the prevalence of vitamin B12 deficiency in elderly population with dementia

Abstract

Aim & Objective: The aim of our study was to determine the prevalence of major types of dementia in our population and to specifically look at the prevalence of B12 deficient dementias.Methodology: A prospective cohort study involving 100 elderly patients with dementia.Results: In our study population, vascular dementia (38%) was more common than Alzheimers (20%) probably due to the high prevalence of diabetes and hypertension.The proportion of reversible dementias were much higher (25%) than other earlier studies and the most common among these was B12 deficiency (19%).bThe average duration to presentation was much shorter in B12 deficiency (10 months). MMSE was much lower in B12 deficiency (13) compared to irreversible causes (16).Thus shorter duration, severe dementia, focal neurological signs and vegetarian diet was significantly associated with development of B12 deficiency. In the diagnosis of B12 deficiency, MCV, peripheral blood smear and LDH had relatively low sensitivities (62.5%, 71% &72.4% respectively) but very high specificities (98.7%, 96.9% &97.5% respectively). B12 deficiency seems to affect more of registration and calculation whereas Alzheimer‘s seems to affect more of orientation and recall. There was a significant and marked improvement in MMSE after treatment in pure B12 deficient patients (by 10 points) if they presented within 1 year of symptoms. There was improvement in other neurological parameters except myelopathy. Multi-infarct state was significantly associated with risk factors- diabetes, hypertension, dyslipidemia, non-vegetarian diet and alcohol intake.Conclusion: Considering this marked improvement and a high prevalence of B12 deficiency in elderly population, we recommend that B12 levels to be done for all elderly dementia patients as it is a potentially treatable cause which can make marked improvement in a patient‘s memory and quality of life.