Does online haemodiafiltration reduce intra-dialytic patient symptoms?

Patients often suffer from symptoms during dialysis. Haemodiafiltration (HDF) therapy has been suggested to be superior to standard haemodialysis (HD). To understand patients' experiences, we quantified the burden and duration of dialysis-associated symptoms to determine whether there was any difference between the modalities.

Symptom questionnaires (83.3%) were returned by 623 dialysis outpatients. Symptom scores were analysed using a visual analogue score. We compared symptom burdens during HD and HDF treatments and also whether the scores changed following a modality change to HDF.

Among the patients, 55.7% were men, the median age was 65 years, 39.7% were diabetic, 26.4% were treated by HDF and the median unadjusted Charlson co-morbidity score was 6 (IQR 4-8). Fatigue (77.3%), intra-dialytic hypotension (76.4%), cramps (74.3%) and dizziness (63%) were the commonest symptoms reported, followed by headache (53.6%) and pruritus (52.2%). Although most symptoms were reported less frequently with HDF [median headache frequency score: HD: 1 (IQR 1-4) vs. HDF: 0 (IQR 0-2), p < 0.005]. There was no evidence of a reduction in symptom scores in patients switching from HD to HDF compared to those remaining on HD.

Patient self-reporting shows that most patients frequently suffer symptoms. There was no evidence that switching to HDF improved symptoms in patients established on HD.