Validity and reliability of the Patient-Reported Outcomes Measurement Information System (PROMIS®) using computerized adaptive testing in patients with advanced chronic kidney disease.

BACKGROUND: The Patient-Reported Outcomes Measurement Information System (PROMIS®) has been recommended for computerized adaptive testing (CAT) of health-related quality of life. This study compared the content, validity, and reliability of seven PROMIS CATs to the 12-item Short-Form Health Survey (SF-12) in patients with advanced chronic kidney disease. METHODS: Adult patients with chronic kidney disease and an estimated glomerular filtration rate under 30 mL/min/1.73 m2 who were not receiving dialysis treatment completed seven PROMIS CATs (assessing physical function, pain interference, fatigue, sleep disturbance, anxiety, depression, and the ability to participate in social roles and activities), the SF-12, and the PROMIS Pain Intensity single item and Dialysis Symptom Index at inclusion and 2 weeks. A content comparison was performed between PROMIS CATs and the SF-12. Construct validity of PROMIS CATs was assessed using Pearson's correlations. We assessed the test-retest reliability of all patient-reported outcome measures by calculating the intraclass correlation coefficient and minimal detectable change. RESULTS: In total, 207 patients participated in the study. A median of 45 items (10 minutes) were completed for PROMIS CATs. All PROMIS CATs showed evidence of sufficient construct validity. PROMIS CATs, most SF-12 domains and summary scores, and Dialysis Symptom Index showed sufficient test-retest reliability (intraclass correlation coefficient ≥ 0.70). PROMIS CATs had a lower minimal detectable change compared with the SF-12 (range, 5.7-7.4 compared with 11.3-21.7 across domains, respectively). CONCLUSION: PROMIS CATs showed sufficient construct validity and test-retest reliability in patients with advanced chronic kidney disease. PROMIS CATs required more items but showed better reliability than the SF-12. Future research is needed to investigate the feasibility of PROMIS CATs for routine nephrology care.

Nocturnal Hemodialysis Leads to Improvement in Physical Performance in Comparison with Conventional Hemodialysis.

End-stage kidney disease patients treated with conventional hemodialysis (CHD) are known to have impaired physical performance and protein-energy wasting (PEW). Nocturnal hemodialysis (NHD) was shown to improve clinical outcomes, but the evidence is limited on physical performance and PEW. We investigate whether NHD improves physical performance and PEW. This prospective, multicenter, non-randomized cohort study compared patients who changed from CHD (2−4 times/week 3−5 h) to NHD (2−3 times/week 7−8 h), with patients who continued CHD. The primary outcome was physical performance at 3, 6 and 12 months, assessed with the short physical performance battery (SPPB). Secondary outcomes were a 6-minute walk test (6MWT), physical activity monitor, handgrip muscle strength, KDQOL-SF physical component score (PCS) and LAPAQ physical activity questionnaire. PEW was assessed with a dietary record, dual-energy X-ray absorptiometry, bioelectrical impedance spectroscopy and subjective global assessment (SGA). Linear mixed models were used to analyze the differences between groups. This study included 33 patients on CHD and 32 who converted to NHD (mean age 55 ± 15.3). No significant difference was found in the SPPB after 1-year of NHD compared to CHD (+0.24, [95% confidence interval −0.51 to 0.99], p = 0.53). Scores of 6MWT, PCS and SGA improved (+54.3 [95%CI 7.78 to 100.8], p = 0.02; +5.61 [−0.51 to 10.7], p = 0.03; +0.71 [0.36 to 1.05], p < 0.001; resp.) in NHD patients, no changes were found in other parameters. We conclude that NHD patients did not experience an improved SPPB score compared to CHD patients; they did obtain an improved walking distance and self-reported PCS as well as SGA after 1-year of NHD, which might be related to the younger age of these patients.

Effects of Conversion to a Bicarbonate/Lactate-Buffered, Neutral-pH, Low-GDP PD Regimen in Prevalent PD: A 2-Year Randomized Clinical Trial.

♦ BACKGROUND: The use of pH-neutral peritoneal dialysis (PD) fluids low in glucose degradation products (GDP) may better preserve the peritoneal membrane and have fewer systemic effects. The effects of conversion from conventional to neutral-pH, low-GDP PD fluids in prevalent patients are unclear. Few studies on the role of neutral-pH, low-GDP PD have studied residual renal function, ultrafiltration, peritonitis incidence and technique failure, transport characteristics, and local and systemic markers of inflammation in prevalent PD patients. ♦ METHODS: In a multi-center open-label randomized clinical trial (RCT), we randomly assigned 40 of 78 stable continuous ambulatory PD (CAPD) and automated PD (APD) patients to treatment with bicarbonate/lactate, neutral-pH, low-GDP PD fluid (Physioneal; Baxter Healthcare Corporation, Deerfield, IL, USA) and compared them with 38 patients continuing their current standard lactate-buffered PD fluid (PDF) (Dianeal; Baxter Healthcare Corporation, Deerfield, IL, USA) during 2 years. Primary outcome was residual renal function (RRF) and ultrafiltration (UF) during peritoneal equilibration test (PET); peritonitis incidence was a secondary outcome. Furthermore, clinical parameters as well as several biomarkers in effluents and serum were measured. ♦ RESULTS: During follow-up, RRF did not differ between the groups. In the Physioneal group ultrafiltration (UF) during PET remained more or less stable (-20 mL [confidence interval (CI): -163.5 - 123.5 mL]; p = 0.7 over 24 months), whereas it declined in the Dianeal group (-243 mL [CI: -376.6 to -109.4 mL]; p < 0.0001 over 24 months), resulting in a difference of 233.7 mL [95% CI 41.0 - 425.5 mL]; p = 0.017 between the groups at 24 months. The peritonitis rate was lower in the Physioneal group: adjusted odds ratio (OR) 0.38 (0.15 - 0.97) p = 0.043. No differences were observed between the 2 groups in peritoneal adequacy or transport characteristics nor effluent markers of local inflammation (cancer antigen [CA]125, hyaluronan [HA], vascular endothelial growth factor [VEGF], macrophage chemo-attractant protein [MCP]-1, HA and transforming growth factor [TGF]ß-1). ♦ CONCLUSION: In prevalent PD patients, our study did not find a difference in RRF after conversion from conventional to neutral-pH, low-GDP PD fluids, although there is a possibility that the study was underpowered to detect a difference. Decline in UF during standardized PET was lower after 2 years in the Physioneal group.

A peritoneal dialysis regimen low in glucose and glucose degradation products results in increased cancer antigen 125 and peritoneal activation.

BACKGROUND: Glucose and glucose degradation products (GDPs) in peritoneal dialysis fluids (PDFs) are both thought to mediate progressive peritoneal worsening. METHODS: In a multicenter, prospective, randomized crossover study, incident continuous ambulatory peritoneal dialysis patients were treated either with conventional lactate-buffered PDF (sPD regimen) or with a regimen low in glucose and GDPs: Nutrineal×1, Extraneal×1, and Physioneal×2 (NEPP regimen; all solutions: Baxter Healthcare, Utrecht, The Netherlands). After 6 months, patients were switched to the alternative regimen for another 6 months. After 6 weeks of run-in, before the switch, and at the end of the study, 4-hour peritoneal equilibration tests were performed, and overnight effluents were analyzed for cells and biomarkers. Differences between the regimens were assessed by multivariate analysis corrected for time and regimen sequence. RESULTS: The 45 patients who completed the study were equally distributed over both groups. During NEPP treatment, D(4)/D(0) glucose was lower (p < 0.01) and D/P creatinine was higher (p = 0.04). In NEPP overnight effluent, mesothelial cells (p < 0.0001), cancer antigen 125 (p < 0.0001), hyaluronan (p < 0.0001), leukocytes (p < 0.001), interleukins 6 (p = 0.001) and 8 (p = 0.0001), and vascular endothelial growth factor (VEGF, p < 0.0001) were increased by a factor of 2-3 compared with levels in sPD effluent. The NEPP regimen was associated with higher transport parameters, but that association disappeared after the addition of VEGF to the model. The association between NEPP and higher effluent levels of VEGF could not be attributed to glucose and GDP loads. CONCLUSIONS: Study results indicate preservation of the mesothelium and increased peritoneal activation during NEPP treatment. Whether the increase in VEGF reflects an increase in mesothelial cell mass or whether it points to another, undesirable mechanism cannot be determined from the present study. Longitudinal studies are needed to finally evaluate the usefulness of the NEPP regimen for further clinical use.

Initiating CAPD with a regimen low in glucose and glucose degradation products, with icodextrin and amino acids (NEPP) is safe and efficacious.

BACKGROUND: The high Levels of glucose, glucose degradation products (GDPs), and lactate buffer present in standard peritoneal dialysis (PD) solutions contribute to peritoneal damage, malnutrition, and dyslipidemia. Therefore, we studied the feasibility of a PD regimen as low as possible in glucose and GDPs. METHODS: In a prospective 30-week study, patients new to continuous ambulatory PD (CAPD) were randomized to either a standard PD regimen (SPD; 4 dwells glucose-/lactate-based) or a low glucose-GDP regimen (NEPP; 1 dwell amino acids, 1 dwell icodextrin, and two dwells bicarbonate/lactate-buffered glucose-based solution). RESULTS: Results obtained during a 30-week study period for 63 new CAPD patients (30 NEPP, 33 SPD) were analyzed. Intraperitoneal glucose load was lower in the NEPP group (111 +/- 76 vs 159 +/- 40 g/day at 30 weeks, p < 0.001). Dialysis efficacy, ultrafiltration, weight, blood pressure, and laboratory results were similar in the groups, whereas, in the NEPP group, cancer antigen 125 in dialysate effluents decreased less but dialysate-to-plasma ratios were slightly higher. CONCLUSION: Short-term treatment of new CAPD patients with a PD regimen low in glucose and GDPs is feasible. Dialysis efficacy, ultrafiltration, and metabolic consequences are similar to those during a standard glucose-lactate-based regimen, whereas peritoneal transport seems slightly higher and preservation of mesothelial cell mass better during NEPP.