Prognosis of the comorbid heart failure and Anemia: A systematic review and meta-analysis

Background

Anemia is found to be an independent risk factor of morbidity, mortality and hospitalization among patients with heart failure. The prevalence, as the potential treatment options of anemia in HF has received increasing clinical interest and epidemiological studies have indicated a variation in the prevalence of anemia in patients with HF.

Method

Electronic search took place in the databases: Pubmed, Cochrane and CINAHL to locate studies in English that investigated the effect of anemia in patients with HF. The overall pooled effect (relative risk, RR) of anemia as comorbid factor compared with HF patients without anemia was estimated by using a random effects analysis (95% confidence interval (CI) for the outcomes of HF — related mortality rate, re-hospitalization and physical condition.

Results

Twenty-six studies were selected. In the overall RR of mortality, re-hospitalization and extended hospitalization was 1.70, 95% CI (1.47–1.98), p < 0.00001, for readmission rate 1.57, 95% CI (1.17, 2.10), p = 0.003 and 1.25, 95% CI (0.59–1.90), p = 0.0002 respectively in behalf of heart failure patients without anemia. Likewise, patients with anemia tend to have worse functionality according to NYHA classification 1.23, 95% (CI 0.99–1.52), p = 0.06. A meta-regression analysis conducted in an effort to explain the heterogeneity of mortality.

Conclusion

The meta-analysis gives an outline profile of patients with the co-morbidity HF and anemia in terms of clinical outcomes. The results point out worse prognosis in HF patients with anemia. Nevertheless, the available data did not allow the extraction of a conclusion in which exact Hb levels anemia becomes a negative predictor of prognosis.