Study of the prevalence of isolated vitamin B12 deficiency related dementia in patients presenting to a tertiary care hospital


  • Patirla Devendra Reddy Department of General Medicine, Konaseema Institute of Medical Sciences, Amalapuram, Andhra Pradesh, India
  • Pranavendra Nath Seela Department of General Medicine, Konaseema Institute of Medical Sciences, Amalapuram, Andhra Pradesh, India
  • Pravin Gulab Rao Maske Department of General Medicine, Konaseema Institute of Medical Sciences, Amalapuram, Andhra Pradesh, India



Dementia, Diet, Mean corpuscular volume, Mini-Mental State Exam score, Vitamin B12 deficiency


Background: Objective of the study was to determine the prevalence of Isolated B12deficient dementia in patients presenting to a tertiary care hospital. The MMSE was much lower in B12 deficiency compared to irreversible causes Thus, shorter duration, severe dementia, focal neurological signs, and a vegetarian diet were significantly associated with the development of B12 deficiency.

Methods: Based on exclusion and inclusion criteria 100 patients were included in this study, a detailed history of the patient were taken with respect to duration of dementia and its symptoms, type and treatment. Study in terms of the correlation of the clinical features with investigations and diet. Estimation of the prevalence of dementia with reference to B12 deficiency. Mean MMSE analysis, assessment of the improvement in MMSE after treatment with B12 injections after a6-8 wks period.

Results: In this study most of our patients were in the 60-69 age groups across all causes of dementia, 22out of 26, B12 deficient patients were vegetarians. This value was in keeping with the known fact that a vegetarian diet predisposes a person to develop B12 deficiency. The association between B12 deficiency, high MCV and megaloblastic blood picture in peripheral blood smear was significant. The MMSE scores were significantly lower 13.42 in patients with B12 deficiency as compared to those with Alzheimer's 14.3 means and those with multi-infarct state 17.3 means.

Conclusions: The duration of the presentation in B12 deficiency was10-12months averagely. There was a significant improvement in MMSE after treatment in pureB12 deficient patients (by 9 points) if they presented within one year of symptoms. Except for myelopathy, there was an improvement in other neurological symptoms and signs. Early diagnosis and proper treatment can make improvements in a patient's memory and quality of life.


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