Oral iron supplementation in patients with heart failure: a systematic review and meta-analysis.
Study Goal
The researchers aimed to assess the safety and efficacy of oral iron supplementation in chronic heart failure patients with iron deficiency or mild anemia.
Results Summary
Oral iron supplementation increased serum iron levels but did not significantly improve transferrin saturation or exercise capacity (6MWT). It was found to be relatively safe with no significant increase in adverse events or mortality compared to placebo.
Population
Chronic heart failure patients with iron deficiency or mild anemia.
Effective Dosage
Not specified
Duration
Not specified
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
oral iron supplementation | no change | all-cause death | patients with HF | RR = 0.77; 95% confidence intervals (CI), 0.46-1.29, Z = 0.98; P = 0.33 | No significant difference was found | #1 |
oral iron treatment | no change | adverse events | patients with HF | RR = 0.83; 95% CI, 0.60-1.16, Z = 1.07; P = 0.28 | were not significantly higher | #2 |
iron complex administration | increase | ferritin levels | patients with HF | mean difference [MD] = 2.70, 95% CI, -2.41 to 7.81, Z = 1.04; P = 0.30 | were slightly increased | #3 |
iron complex administration | increase | Tsat | patients with HF | MD = 27.42, 95% CI, -4.93 to 59.78, Z = 1.66; P = 0.10 | were slightly increased | #4 |
oral iron supplementation | no change | exercise capacity | patients with HF | MD = 59.60, 95% CI, -17.89 to 137.08, Z = 1.51; P = 0.13 | No significant difference was found | #5 |
oral iron supplementation | increase | serum iron levels | patients with HF and ID or mild anaemia | MD = 28.87, 95% CI, 1.62-56.12, Z = 2.08; P = 0.04 | increased | #6 |
oral iron supplementation | no change | Tsat | patients with HF and ID or mild anaemia | - | does not improve | #7 |
oral iron supplementation | no change | 6MWT | patients with HF and ID or mild anaemia | - | does not improve | #8 |
AIMS: This review aimed to assess whether oral iron supplementation in a chronic heart failure (HF) population with iron deficiency (ID) or mild anaemia is safe and effective according to evidence-based medicine. METHODS: We retrieved 1803 records from the PubMed, Embase, and the Cochrane Library databases from 1 January 1991 to 15 September 2021. The clinical outcome of oral iron supplementation for ID anaemia in patients with HF was the primary endpoint. The primary safety measures included adverse events and all-cause mortality, and efficacy measures included transferrin saturation (Tsat), ferritin levels, and the 6-min walk test (6MWT). The rate ratio (RR) was used to pool the efficacy measures. RESULTS: Five randomized controlled trials that compared oral iron treatment for patients with the placebo group and included a combined total of 590 participants were analysed. No significant difference was found in all-cause death between oral iron treatment and placebo groups (RR = 0.77; 95% confidence intervals (CI), 0.46-1.29, Z = 0.98; P = 0.33). However, adverse events were not significantly higher in the iron treatment group (RR = 0.83; 95% CI, 0.60-1.16, Z = 1.07; P = 0.28). In addition, ferritin levels and Tsat were slightly increased after iron complex administration in patients with HF but were not statistically significant (ferritin: mean difference [MD] = 2.70, 95% CI, -2.41 to 7.81, Z = 1.04; P = 0.30; Tsat: MD = 27.42, 95% CI, -4.93 to 59.78, Z = 1.66; P = 0.10). No significant difference was found in exercise capacity, as indicated by the 6MWT results (MD = 59.60, 95% CI, -17.89 to 137.08, Z = 1.51; P = 0.13). We also analysed two non-randomized controlled trials with follow-up results showing that oral iron supplementation increased serum iron levels (MD = 28.87, 95% CI, 1.62-56.12, Z = 2.08; P = 0.04). CONCLUSIONS: Based on the current findings, oral iron supplementation can increase serum iron levels in patients with HF and ID or mild anaemia but does not improve Tsat and 6MWT. In addition, oral iron supplementation is relatively safe.