Psychological outcomes in critically ill patients receiving renal replacement therapy: a matched-pairs analysis

We conducted a single-centre observational study over fiveyears to assess the impact of renal replacement therapy on the psychological health of survivors of critical illness. We hypothesised that the added burden of renal replacement would increase the prevalence and severity of anxiety, depression and stress reactions in these patients, compared with matched pairs (matched for age, sex and APACHE II score) who did not receive renal replacement. Participants completed postal questionnaires. A total of 342 patients with acute kidney injury received renal replacement. One hundred and seventy-nine (52.3%) survived to hospital discharge, and 161 (47.1%) were alive at 90days. Seventy-seven (47.8% of survivors) completed questionnaires. We found 77 matches for the Hospital Anxiety and Depression Scale analysis and 72 for the Impact of Events Scale analysis. Clinically relevant symptoms of psychiatric morbidity were common, with anxiety and depression affecting 49 (63.6%) patients and stress reactions affecting 24 (33.3%) patients. Mean scores (95% CI) were 11.4 (9.6-13.2) and 20.1 (15.7-24.6), respectively. On multivariate analysis, we found no significant differences between renal replacement patients and controls, in either the frequency or severity of these symptoms.