Effectiveness of bioimpedance spectroscopy on dry weight (DW) measurement in haemodialysis patients: a systematic review

Aim To review the effects of bioimpedance spectroscopy (BIS) to measure dry weight (DW) in haemodialysis (HD)patients when compared to clinical examination. Methods The review was conducted according to the Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument (JBI-MasARI). Meta-analysis was performed using Review Manager 5 software. The search was limited to English language papers published from 2005 to 2017. A standard JBI three-step search strategy was used. We searched all quantitative studies from major databases for investigations of the BIS for measuring DW in HD patients. Results A total of four randomised controlled trials (RCTs) met the inclusion criteria. These studies all involved patients with end-stage kidney disease (ESKD) receiving HD and the comparison of BIS versus physician’s clinical judgement using cardiovascular parameters and mortality outcomes. The meta-analysis of BIS when compared with clinical judgement found no significant differences in the reduction of the mortality rate, hospitalisation rate or other cardiovascular parameters after 12 months of the intervention; only significant improvement in pre-dialysis systolic BP (WMD –5.41, 95% CI –9.00 to –1.82; p=0.003) was reported. However, individual RCTs found that BIS is an effective intervention for HD patients in the reduction of the mortality rate (HR 0.100, 95% CI, 0.013 to 0.805; p=0.04) after 2.5 years of the intervention. Conclusion The small number of participants and restricted participant selection criteria all has considerable impact with regard to generalising these findings to wider HD populations.