Evidence map›Paper›PMID 20573208›Full record

SynthesisBMC geriatrics2010

Subnormal vitamin B12 concentrations and anaemia in older people: a systematic review.

Wendy P J den Elzen, Gerda M van der Weele, Jacobijn Gussekloo, Rudi G J Westendorp, Willem J J Assendelft

Open access · goldAbstract readComparative StudySystematic Review
In one paragraph

Synthesis in BMC geriatrics, 2010. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 6 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
6citing papers in PubMed, 1 pooled it
2.0field-weighted citation impact, top 14% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

6 citing papers in PubMed, 1 synthesis or guideline pooled it, 30 citations in OpenAlex.

  1. Pooled it
  2. Vitamin BBMC geriatrics · 2024
    Article
  3. Vitamin BNutrients · 2020
    Article
  4. Article
  5. Proton pump inhibitors: Review of reported risks and controversies.Laryngoscope investigative otolaryngology · 2018
    Review
  6. Not so benign haematology: anaemia of the elderly.British journal of haematology · 2012
    Review
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors at 1 institution in 1 country.

Wendy P J den ElzenDepartment of Public Health and Primary Care, Leiden University Medical Center, Leiden, The Netherlands. w.p.j.den_elzen@lumc.nl
Gerda M van der Weele
Jacobijn Gussekloo
Rudi G J Westendorp
Willem J J Assendelft
Leiden University Medical Center · NL

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundPernicious anaemia is undeniably associated with vitamin B12 deficiency, but the association between subnormal vitamin B12 concentrations and anaemia in older people is unclear. The aim of this systematic review was to evaluate the association between subnormal vitamin B12 concentrations and anaemia in older people.

methodsClinical queries for aetiology and treatment in bibliographic databases (PubMed [01/1949-10/2009]; EMBASE [01/1980-10/2009]) were used. Reference lists were checked for additional relevant studies. Observational studies (> or =50 participants) and randomized placebo-controlled intervention trials (RCTs) were considered.

results25 studies met the inclusion criteria. Twenty-one observational cross-sectional studies (total number of participants n = 16185) showed inconsistent results. In one longitudinal observational study, low vitamin B12 concentrations were not associated with an increased risk of anaemia (total n = 423). The 3 RCTs (total n = 210) were well-designed and showed no effect of vitamin B12 supplementation on haemoglobin concentrations during follow-up in subjects with subnormal vitamin B12 concentrations at the start of the study. Due to large clinical and methodological heterogeneity, statistical pooling of data was not performed.

conclusionsEvidence of a positive association between a subnormal serum vitamin B12 concentration and anaemia in older people is limited and inconclusive. Further well-designed studies are needed to determine whether subnormal vitamin B12 is a risk factor for anaemia in older people.

Indexed as

AgedAge FactorsCross-Sectional StudiesDementiaHumansLongitudinal StudiesRandomized Controlled Trials as TopicVitamin B 12Vitamin B 12 DeficiencyVitamin B 12

Identifiers

PMID20573208
PMCPMC2900261
OpenAlexW2059695155

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.