title: Vitamin B12 deficiency in the institutionalized elderly: A regional study.
abstract: The prevalence of vitamin B12 deficiency increases with age and is suggested to be even higher in the elderly living in institutions. This retrospective study evaluated the vitamin B12 and folate status of 1996 institutionalized elderly residents aged over 65years. Among them, 34.9% had vitamin B12 deficiency (serum vitamin B12 <150pmol/L), 11.8% had folate deficiency (serum folate <6.8nmol/L), and 4.9% had both. The majority of vitamin B12 deficient residents (68%) had serum vitamin B12 between 100pmol/L and 149pmol/L. Macrocytosis was found in 24.2% of vitamin B12 deficient residents. A significant increase in macrocytosis was associated with a decrease in serum vitamin B12 below 100pmol/L. Macrocytosis was most common in those with vitamin B12 ≦69pmol/L (50.9%). Overall, vitamin B12 deficiency is common in the institutionalized elderly, however macrocytosis cannot predict deficiency. More liberal testing for vitamin B12 status in the institutionalized elderly may be warranted.
authors.affiliation: Caritas Medical Centre (Hospital Authority), Wing Hong Street, Shum Shiu Po, Kowloon, Hong Kong, China. Electronic address: chitwaiwong@hotmail.com.
authors.forename: C W
authors.initials: CW
authors.lastname: Wong
authors.affiliation: Caritas Medical Centre (Hospital Authority), Wing Hong Street, Shum Shiu Po, Kowloon, Hong Kong, China.
authors.forename: C Y
authors.initials: CY
authors.lastname: Ip
authors.affiliation: Caritas Medical Centre (Hospital Authority), Wing Hong Street, Shum Shiu Po, Kowloon, Hong Kong, China.
authors.forename: C P
authors.initials: CP
authors.lastname: Leung
authors.affiliation: Caritas Medical Centre (Hospital Authority), Wing Hong Street, Shum Shiu Po, Kowloon, Hong Kong, China.
authors.forename: C S
authors.initials: CS
authors.lastname: Leung
authors.affiliation: Caritas Medical Centre (Hospital Authority), Wing Hong Street, Shum Shiu Po, Kowloon, Hong Kong, China.
authors.forename: J N
authors.initials: JN
authors.lastname: Cheng
authors.affiliation: Caritas Medical Centre (Hospital Authority), Wing Hong Street, Shum Shiu Po, Kowloon, Hong Kong, China.
authors.forename: C Y
authors.initials: CY
authors.lastname: Siu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002681:China / Q000453:epidemiology; D004909:Erythrocyte Indices; D005260:Female; D005492:Folic Acid / Q000097:blood*; D005494:Folic Acid Deficiency / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D007326:Institutionalization / Q000706:statistics & numerical data*; D008297:Male; D015995:Prevalence; D012112:Residential Facilities / Q000706:statistics & numerical data; D012189:Retrospective Studies; D014805:Vitamin B 12 / Q000097:blood*; D014806:Vitamin B 12 Deficiency / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology
chemical_list: D005492:Folic Acid; D014805:Vitamin B 12
keywords: Anaemia; Elderly; Folate; Institution; Macrocytosis; Vitamin B(12); Vitamin B(12) deficiency