Systematic Review and Meta-analysis: What is the Evidence for Oral Iron Supplementation in Treating Anaemia in Older People?

HS Tay1, RL Soiza1,2. 1NHS Grampian, Aberdeen, Scotland, UK, 2University of Aberdeen, Aberdeen, Scotland, UK

Introduction: Anaemia is common in elderly people. Oral iron supplementation is widely used to treat iron deficiency despite observational studies suggesting it is ineffective, potentially due to poor absorption from the aged gut or adverse drug effects. Therefore, this systematic review determined if oral iron therapy is effective in elderly people with anaemia due to iron deficiency or after acute blood loss.

Methods: The systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guideline. MEDLINE, Embase and the Cochrane library were searched from inception up to 23rd January 2014. Only randomised controlled trials comparing oral iron with no iron supplementation or placebo and measuring the change in haemoglobin levels in elderly people with anaemia were included.

Results: 6163 titles were screened but only three studies1-3 (total 440 participants, mean age 70-83y) met the inclusion criteria, all in an orthopaedics setting. Just one showed oral iron supplementation significantly raised haemoglobin level. However, meta-analysis showed oral iron supplementation was more effective than placebo or no treatment after 4-6 weeks of treatment (weighted mean difference 0.35g/dL, 95% CI 0.12-0.59, p=0.003). Oral iron supplementation did not significantly shorten the length of hospitalisation, change one month mortality nor improve quality of life.

Conclusion: Oral iron raises haemoglobin levels in elderly people with post-operative anaemia by about 0.35g/dL after 4-6 weeks. However, only 3 studies in an orthopaedics setting met inclusion criteria. It remains unclear if the widespread practice of prescribing oral iron supplements results in tangible benefits for older people with anaemia due to iron deficiency or blood loss.

References :

1. Sutton E et al. (2004). Journal of Bone and Joint Surgery 86(1):31.

2. Prasad N et al. (2009). Injury 40(10):1073.

3. Parker MJ (2010). J Bone Joint Surg Am 92:265.

Forest plot shows the increase in haemoglobin level with oral iron supplementation. The squares are given to the continuous outcome and the size of the squares depends on the weight of each studies. The diamond signifies the mean difference is in favour of the iron group. The direction is consistent in all studies.