Patient Self-Testing of Kidney Function at Home, a Prospective Clinical Feasibility Study in Kidney Transplant Recipients

Murray, Jonathan S.; Williams, Cameron J.; Lendrem, Clare; Smithson, Joanne; Allinson, Clare; Robinson, Jennifer; Walker, Alycon; Winter, Amanda; Simpson, A John; Newton, Julia; Wroe, Caroline; Jones, William S.

Abstract

Introduction
People with long-term health conditions often attend clinics for kidney function tests. The Self-Testing Own Kidneys (STOK) study assessed feasibility of kidney transplant recipients using hand-held devices to self-test kidney function at home and investigated agreement between home self-test and standard clinic test results.

Methods
A prospective, observational, single-center, clinical feasibility study (TRN: ISRCTN68116915), with N = 15 stable kidney transplant recipients, investigated blood potassium and creatinine results agreement between index self-tests at home (patient self-testing of capillary blood, using Abbott i-STAT Alinity analyzers [i-STAT]) and reference tests in clinic (staff sampled venous blood, analyzed with laboratory Siemens Advia Chemistry XPT analyzer) using Bland-Altman and error grid analysis.

Results
The mean within-patient difference between index and reference test in creatinine was 2.25 μmol/l (95% confidence interval [CI]: −12.13, 16.81 μmol/l) and in potassium was 0.66 mmol/l (95% CI: −1.47, 2.79 mmol/l). All creatinine pairs and 27 of 40 (67.5%) potassium pairs were judged clinically equivalent. Planned follow-up analysis suggests that biochemical variables associated with potassium measurement in capillary blood were predominant sources of paired test result differences. Paired patient and nurse i-STAT capillary blood test potassium results were not statistically significantly different.

Conclusions
This small feasibility study observed that training selected patients to competently use hand-held devices to self-test kidney function at home is possible. Self-test creatinine results showed good analytical and clinical agreement with standard clinic test results. Self-test potassium results showed poorer agreement with standard clinic test results; however, patient use of hand-held devices to self-test at home was not a statistically significant source of paired potassium test result differences.

Citation

Murray, J. S., Williams, C. J., Lendrem, C., Smithson, J., Allinson, C., Robinson, J., …Jones, W. S. (2023). Patient Self-Testing of Kidney Function at Home, a Prospective Clinical Feasibility Study in Kidney Transplant Recipients. Kidney International Reports, 8(6), 1170-1182. https://doi.org/10.1016/j.ekir.2023.03.003

• Journal Article Type: Article
• Acceptance Date: Mar 6, 2023
• Online Publication Date: Mar 27, 2023
• Publication Date: Jun 1, 2023
• Deposit Date: Jul 26, 2023
• Publicly Available Date: Jul 27, 2023
• Journal: Kidney International Reports
• Print ISSN: 2468-0249
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 6
• Pages: 1170-1182
• DOI: https://doi.org/10.1016/j.ekir.2023.03.003
• Keywords: Creatinine; Home; Kidney; Point-of-care test; Potassium; Self-test
• Public URL: https://hull-repository.worktribe.com/output/4297869
• Publisher URL: https://www.kireports.org/article/S2468-0249(23)01216-0/fulltext
• Additional Information: This article is maintained by: Elsevier; Article Title: Patient Self-Testing of Kidney Function at Home, a Prospective Clinical Feasibility Study in Kidney Transplant Recipients; Journal Title: Kidney International Reports; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.ekir.2023.03.003; Content Type: article; Copyright: © 2023 Published by Elsevier, Inc., on behalf of the International Society of Nephrology.