Improving Patient Assessment After Acute Kidney Injury (AKI) (IMPACT-AKI)

The goal of this clinical trial is to improve patient care after acute kidney injury (AKI). It has three related parts. The main questions it aims to answer are:

1. Is creatinine or cystatin a more reliable assessment of kidney function after AKI?
2. What are the experiences of patients after AKI?
3. What interventions should be recommended to improve assessment and support of patients after AKI?

Participants will be asked to do one or more of:

• blood tests to measure kidney function in different ways
• have measurement of their body composition
• complete questionnaires about their symptoms
• have an interview with a researcher about their experiences
• discussion to develop an action plan based on findings

Study Overview

• Status: Recruiting
• Conditions: Acute Kidney Injury
• Intervention / Treatment: Diagnostic test: Iohexol renal clearance measurement; Diagnostic test: Cystatin C; Diagnostic test: Creatinine; Diagnostic test: Metagenome analysis; Diagnostic test: Bioimpedance analysis; Other: Patient reported outcome measures; Other: Measurement of physical performance; Other: Semi structured interview; Other: Participatory workshop

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Kerry Horne Dr, BMBCh; Phone Number: +44 01332 788262; Email: kerry.horne@nottingham.ac.uk

Study Locations

• United Kingdom
  • Derbyshire
    • Derby, Derbyshire, United Kingdom, DE22 3DT
      • Recruiting
      • University Hospitals of Derby and Burton NHS Foundation Trust
      • Contact: Kerry Horne Dr; Phone Number: 01332788262; Email: kerry.horne@nottingham.ac.uk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Observational study workstream: secondary care nephrology clinics Qualitative interview workstream: secondary care nephrology clinics, hospitalised patients with AKI not followed up in nephrology clinic, participants of other aspects of the study.

Participatory workshop workstream: Organisational and professional organisations with interest in acute kidney injury, professional networks, public and patient involvement and engagement groups

Description

Inclusion Criteria:

Observational study workstream

• Age 18-85 years
• AKI stage 2 or 3 during hospital admission OR AKI stage 1 of at least 7 days duration during hospital admission
• 60-90 days after peak creatinine Qualitative interview workstream
• Age 18-85 years
• AKI during hospital admission
• 60-90 days after peak creatinine Participatory workshop workstream
• Age 18-85 years
• Relevant experience (as assessed by the investigator) which could include personal experience of an episode of hospitalised AKI as a patient of carer, experience of managing AKI or related problems in a professional capacity or knowledge of a particular community.

Exclusion Criteria:

Observational study workstream

• Inability to give informed consent
• No baseline creatinine available in previous 12 months
• Pregnancy or breastfeeding
• Current treatment with dialysis
• Renal transplant
• Pacemaker in situ
• Previous amputation
• Allergy to Omnipaque contrast agent (WP1 only)
• Manifest thyrotoxicosis (WP1 only)
• Ascites or significant (grade 3 to 4) peripheral oedema, defined as ≥6 mm pit, lasting for >1 minute after 5-second compression over tibia or medial malleolus (WP1 only) Qualitative interview workstream
• Inability to give informed consent
• No baseline creatinine available in previous 12 months
• Current treatment with dialysis
• Renal transplant
• Receiving palliative care Participatory workshop workstream
• Inability to give informed consent
• Inability to communicate in English (the qualitative workshops will be held in English)

Study Plan

How is the study designed?

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Observational study; Patients 3 months after hospitalised acute kidney injury	Diagnostic test: Iohexol renal clearance measurement; Gold standard measurement of glomerular filtration rate.; Diagnostic test: Cystatin C; Estimated GFR using serum cystatin C; Diagnostic test: Creatinine; eGFR from serum creatinine level; Diagnostic test: Metagenome analysis; Analysis of the metagenome using faecal samples of participants after acute kidney injury; Diagnostic test: Bioimpedance analysis; Estimation of body composition; Other: Patient reported outcome measures; EQ-5D-5L, KSQ, WHO-DAS 2.0, K10; Other: Measurement of physical performance; Hand grip, Short physical performance battery
Qualitative study; Patients 3 months after hospitalised acute kidney injury	Other: Semi structured interview; Semi structured interview to explore patient experiences. Purposive sampling will be used to explore a wide range of perspectives and transcripts will be analysed using thematic analysis to develop codes and themes.
Participatory workshops; Individuals with personal or professional experience of acute kidney injury	Other: Participatory workshop; Group workshop using qualitative methods. Purposive sampling will be used to explore a wide range of perspectives and transcripts will be analysed using thematic analysis to develop codes and themes. These will be used to develop consensus recommendations.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The proportion of eligible patients who agree to participate		3 months
The proportion of participants who have all three measurements (eGFR-cystatin, eGFR-creatinine and measured GFR)		3 months
Standard deviation of the difference between measured GFR and eGFR-creatinine and eGFR-cystatin		3 months
The proportion of patients with eGFR <60ml/min/1.73m2 from eGFR-cystatin compared with eGFR creatinine		3 months
Gut microbiome composition	Assessed through metagenomics	3 months
Codes and themes related to patient experience after AKI, identified from systematic qualitative analysis of interview transcripts		3 - 12 months
Production of a document of recommended next steps through MDT development during participatory workshops		At completion of third workshop 3 years after enrolment

Secondary Outcome Measures

Outcome Measure	Time Frame
The mean difference between eGFR-cystatin and eGFR-creatinine	3 months
The mean difference between iohexol measured GFR and each estimated GFR method (creatinine and cystatin)	3 months
Correlation between eGFR creatinine and eGFR cystatin	3 months
Correlation between iohexol measured GFR and each estimated GFR method (creatinine and cystatin)	3 months
Bias between iohexol measured GFR and each estimated GFR method (creatinine and cystatin)	3 months
Accuracy of eGFR creatinine and eGFR cystatin compared with iohexol measured GFR as assessed by the percentage of estimated values within 30% of measured GFR (P30)	3 months
Correlation of muscle mass with the percentage difference between eGFR-cystatin and eGFR-creatinine	3 months
Correlation of physical function with the percentage difference between eGFR-cystatin and eGFR-creatinine	3 months
Correlation of patient reported outcomes with the percentage difference between eGFR-cystatin and eGFR-creatinine	3 months
Barriers to implementation of recommendations as identified through MDT discussion at participatory workshops	At completion of third workshop 3 years after enrolment

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Safety Outcomes	Adverse events spontaneously reported during the study; Discontinuation due to adverse events	From enrolment until the end of study visits (from 3 to 12 months)

Collaborators and Investigators

• Sponsor: University of Nottingham
• Collaborators: University Hospitals of Derby and Burton NHS Foundation Trust
• Investigators: Principal Investigator: Nicholas Selby, University of Nottingham

Study record dates

Study Major Dates

• Study Start (Actual): February 16, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): October 1, 2029

Study Registration Dates

• First Submitted: January 29, 2026
• First Submitted That Met QC Criteria: May 1, 2026
• First Posted (Actual): May 6, 2026

Study Record Updates

• Last Update Posted (Actual): May 6, 2026
• Last Update Submitted That Met QC Criteria: May 1, 2026
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: chronic kidney disease; acute kidney injury; patient reported outcome measures
• Additional Relevant MeSH Terms: Urogenital Diseases; Pathologic Processes; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Chronic Disease; Disease Attributes; Renal Insufficiency; Pathological Conditions, Signs and Symptoms; Acute Kidney Injury; Renal Insufficiency, Chronic; Health Services Administration; Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Data Collection; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Health Care Economics and Organizations; Outcome Assessment, Health Care; Outcome and Process Assessment, Health Care; Surveys and Questionnaires; Health Planning; Health Care Surveys; Health Services Research; Patient Outcome Assessment; Patient Reported Outcome Measures
• Other Study ID Numbers: 25019

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: IPD sharing will be available on request through the study team and individual applications will be considered.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No