Patients aged 65 years or older with end-stage kidney disease may experience stabilization or improvement in their symptom number and burden after starting dialysis, according to a large European study.
Investigators led by Esther N.M. de Rooij, MD, of Leiden University Medical Center in The Netherlands, hypothesize that their findings may help better inform older patients with kidney failure about what to expect regarding the development of their symptom burden during the first year after starting dialysis.
The team analyzed data from 456 incident dialysis patients (75% men) in the European Quality (EQUAL) study, an ongoing, prospective multicenter study of patients aged 65 years or older with an incident estimated glomerular filtration rate (eGFR) of 20 mL/min per 1.73 m2 or less. At dialysis initiation, patients had a mean age of 76 years and a mean eGFR of 8 mL/min per 1.73 m2. Of the cohort, 44% had diabetes and 46% had cardiovascular disease.
The investigators used the dialysis symptom index (DSI) questionnaire to analyze 30 symptoms every 3 to 6 months from 2012 to 2021. Symptom scores ranged from 0 to 30 and symptom burden ranged from 0 to 150, with higher scores indicating greater severity. The most common symptoms with the highest burden were “fatigue” (81%, burden 2.7), “decreased interest in sex” (69%, burden 2.4), and “difficulty becoming sexually aroused” (68%, burden 2.3) at dialysis initiation.
In the year before dialysis, symptom number increased by 3.6 and burden number increased by 13.3. In the year after dialysis, the symptom number stabilized or decreased by 0.9 and symptom burden decreased by 5.9. At dialysis initiation, “fatigue,” “decreased interest in sex,” and “difficulty becoming sexually aroused” had the highest prevalence. Fatigue improved somewhat after dialysis initiation, whereas the prevalence and burden of sexual symptoms further increased.
The authors wrote that inquiring about sexual symptoms may help patients to address these sensitive and burdensome problems. “As patient-reported outcome measures, such as symptom questionnaires, are becoming more frequently incorporated in routine nephrology clinical care, individual symptom burden can now be measured in a standardized manner,” the authors concluded.
Dr de Rooij and colleagues acknowledged the study’s limitations. They could not include all EQUAL patients on dialysis because DSI questionnaires were only available for 77% of all patients on dialysis during the year before and after dialysis initiation. In addition, DSI questionnaires were missing in 32% of all study visits during follow-up.
“I think this is an important study that addresses an area that has not received enough attention, the impact of kidney failure on symptoms, and whether dialysis significantly improves those symptoms,” said Michael Heung, MD, Professor of Medicine at the University of Michigan in Ann Arbor. “The traditional assumption has been that of course dialysis improves symptoms, but there hasn’t been much formal study to prove this.”
Typically, studies have focused on “hard” outcomes such as survival, and Dr Heung said that tends to emphasize quantity over quality of life. “Kudos to the authors for examining the issue of symptoms in a rigorous manner. Unfortunately, I was surprised that there was not a more significant improvement in symptoms or symptom burden after initiation of dialysis,” he said.
Dr Heung cautioned, however, that the study cohort consisted of older predominantly White European patients. “Whether the same findings apply to the US population cannot be assumed, as there can be differences in culture, diet, etc.,” he said.
Future research, he said, should try to identify which patients benefit the most from dialysis initiation and by extension which patients are unlikely to see significant symptom improvement. “That would further help clinicians to counsel patients on what to expect and provide a more informed basis for the decision to pursue dialysis therapy,” Dr Heung said.
Sara Davison, MD, Professor of Medicine at the University of Alberta in Edmonton, Canada, echoed that view, noting that prospective, randomized trials are warranted to better understand which patients may feel better than others based not only on age and initial symptom burden but also factors such as comorbidity and physical and cognitive function.
As with nearly all symptom studies, she said, Dr de Rooij and colleagues reported mean data, “which does not help us understand who will do well with dialysis and who will not.”
Dr Davison added, “Symptom studies should include responder analyses, so we can better understand what proportion and hopefully who will improve and vice versa. This is ultimately what we need to help patients with shared decision-making.”
de Rooij ENM, Meuleman Y, de Fijter JW, et al. Symptom burden before and after dialysis initiation in older patients. Clin J Amer Soc Nephrol. Published online November 10, 2022. doi:10.2215/CJN.09190822