Renin-angiotensin system inhibitors linked to anemia: a systematic review and meta-analysis.
Cheungpasitporn W, Thongprayoon C, et al.Qjm 2015; 108(11): 879-884.
Aims
Evaluate risk of anaemia in patients who used renin-angiotensin system (RAS) inhibitors.
Interventions
A systematic review was carried out for published studies indexed in MEDLINE, EMBASE and the Cochrane database from inception through November, 2014. Studies that reported relative risks, odd ratios or hazard ratios comparing the anaemia risk in patients who received angiotensin-converting-enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) to those who did not were included.
Participants
Seven studies (2 cohort and 5 cross-sectional studies) with 29,061 patients were included in the data analysis.
Outcomes
Outcome of interest was risk of aneamia using ACEIs or ARBs. Anaemia was defined by heamoglobin levels.
Follow-up
Not described
CET Conclusions
This systematic review and meta-analysis examines the effect of RAS blockade on the risk of anaemia. Whilst the inclusion criteria did not limit to studies in renal transplant recipients, three of the seven included in the analysis were in transplant patients, and the results were presented separately. The authors reported a significant increase in the relative risk of anaemia with use of both ACEi and ARBs, a potentially important finding given the risk of sensitisation with repeat transfusion in transplant patients. What is most notable about this study are the paucity of data, and that all seven included studies were observational in nature. This possibly relates to the outcome used – many RCTs of ACEi/ARB record haemoglobin as a continuous outcome rather than anaemia as a binary measure. In a previous Cochrane review of antihypertensive therapy in renal transplant recipients, mean haemoglobin levels were 11.7 g/L lower in the ACEi group compared to placebo (http://onlinelibrary.wiley.com/doi/10.1002/14651858.CD003598.pub2/full). Thus the outcome chosen here may have limited the quality of the included evidence.
Quality notes
Quality assessment not appropriate
Trial registration
None