The Efficacy of Ascorbic Acid in Suboptimal Responsive Anemic Hemodialysis Patients Receiving Erythropoietin: A Meta-Analysis
Brad Einerson PharmD*, ** Nathorn Chaiyakunapruk PharmD, PhD *,**,***, Chagriya Kitiyakara MBBS, MRCP****, Sirada Maphanta PharmD, MSBCPS*, Visanu Thamlikitkul MD, MS*****
Affiliation : * Center of Pharmaceutical Outcomes Research, Department of Pharmacy Practice, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok, Thailand. ** School of Pharmacy, University of Wisconsin, Madison, USA *** School of Population Health, University of Queensland, Australia **** Department of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand ***** Department of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
Background : To determine the impact of adjuvant ascorbic acid therapy on erythropoietin-hyporesponsive, anemic patients
undergoing hemodialysis.
Data Sources: The online databases of PubMed, Cochrane library, IPA, CINAHL, EMBASE, clinicaltrial.gov, WHO trial
registry and PyschINFO were used.
Study Selection: Studies comparing ascorbic acid to a control, with participants receiving erythropoietin and hemodialysis,
and reported outcomes for hemoglobin or transferring saturation.
Data Extraction: Two independent researchers reviewed titles and abstracts to determine relevance and extracted study
design, dose, duration, baseline values, and outcomes.
Data Synthesis: Five studies met all the criteria and were used for final analysis. The calculated weighted mean difference
between hemoglobin in the ascorbic acid group versus the control group was 0.96 g/dL (95% CI, 0.78 to 1.14). The calculated
weighted mean difference between transferrin saturation in the ascorbic acid treatment group versus the control was 8.26%
(95% CI, 6.59 to 9.94).
Conclusion : Adjuvant ascorbic acid significantly raises hemoglobin levels in patients with erythropoietin hyporesponsiveness
undergoing hemodialysis. The significant rise in transferrin saturation indicates that this positive effect on erythropoietin
response may be due to increased iron utilization.
Keywords : Ascorbic acid, Erythropoietin hyporesponsiveness, Hemodialysis, Anemia, Meta-analysis
