Association between serum vitamin B12 level and frailty in older adults

Frailty is associated with recurrent falls, fractures, limitation of daily living activities, cognitive impairment, increase in hospitalization, placement in nursing home, and mortality rate in older adults. Although malnutrition is one of the most important etiological factors, role of micronutrients is unclear. The aim of this study was to investigate association between frailty and vitamin B12, which has been demonstrated to be related to numerous geriatric syndromes.

Total of 335 patients who presented at geriatric outpatient clinic and underwent comprehensive geriatric assessment were included in this study. All patients were evaluated with both Fatigue, Resistance, Ambulation, Illnesses, and Loss of Weight (FRAIL) scale and Fried criteria for frailty. Vitamin B12 deficiency was defined as serum vitamin B12 level of less than 400 pg/mL.

In total of 335 patients, 88 (26.3%) were assessed as frail, 156 (46.6%) were prefrail, and 91 (27.2%) were robust. When the 3 groups were compared, it was found that patients in frail group had highest average age and lowest education level (p<0.001) and that complaints of urinary incontinence, balance disorders, recurrent falls, sleep disorders, amnesia, chronic pain, and constipation were more frequent in this group (p<0.05). Albumin and 25-hydroxy vitamin D levels decreased as frailty level increased (p<0.05), but no association between vitamin B12 levels and frailty was found. Patients were divided into 2 groups: vitamin B12 level above and below 400 pg/mL. Groups were then compared in terms of subparameters of both the FRAIL and Fried criteria, and no significant difference between groups was found (p>0.05).

Results of this study determined no association between vitamin B12 level and frailty in geriatric population; however, longitudinal studies are needed to clarify relationship.