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., Walker, A., Winter, A., Simpson, A. J., Newton, J., Wroe, C., & 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.