How many UK adults developed kidney failure since the year 2000? What treatments did they receive and what were their health outcomes?

Date of Approval
Application Number
21_000459
Technical Summary

The UK Kidney Association is extending quality assurance to all individuals reaching kidney failure. Dialysis and transplantation are nationally audited, but the population that does not receive dialysis/transplantation is not captured. The characteristics, healthcare and outcomes for this latter group are poorly documented in the UK. Studies in Canada and Australia suggested as many reach kidney failure and die as those who start dialysis or receive a transplant. This work will provide vital data to inform national kidney service planning, by capturing and describing the population of individuals in CPRD who reach kidney failure, and by unpacking the associations between patient factors and access to specialist services.

Aim:
• Use CPRD and HES to describe the demographic, clinical and treatment characteristics of the population within CPRD that developed kidney failure since 31st December 1999.

Population:
• Individuals in CPRD Gold/Aurum incident to kidney failure, defined by kidney function (eGFR) <15, initiation of dialysis, or kidney transplantation.

Objectives:
• Estimate the total UK population incident to kidney failure.
• Compare treatment and outcomes of individuals stratified by specialist review, and by receipt of dialysis/transplantation.
• Analyse the association between patient factors and review by a kidney specialist; and initiation of dialysis/transplantation.

The first two objectives involve descriptive statistics only. Primary analysis will be conducted using all CPRD-registered practices. Secondary analyses will restrict to individuals with HES linkage. Incidence rates by age/sex/ethnicity from the CPRD data will be applied to the UK population (from the UK census) to estimate UK-wide incidence.
The final objective will apply logistic regression to assess the hypotheses that the likelihood of ever receiving specialist review, or ever receiving dialysis/transplantation [co-primary outcomes] are associated with the age, sex, ethnicity, index of multiple deprivation, Charlson comorbidity index, and electronic frailty index of an individual reaching kidney failure [exposures].

Health Outcomes to be Measured

Kidney specialist review;
Dialysis receipt;
Kidney transplantation;
All cause mortality, cause and date of death;
Hospital admissions and total hospital days;
Primary care attendance;
Diabetology review;
Palliative care input;
Blood pressure control;
HbA1c;
Markers of renal anaemia: haemoglobin level, ferritin;
Markers of renal bone disease: calcium, phosphate and parathyroid hormone;
Serum potassium;
Medications prescribed.

Collaborators

Fergus Caskey - Chief Investigator - University of Bristol
Barnaby Hole - Corresponding Applicant - University of Bristol
Ailish Nimmo - Collaborator - University of Bristol
Lucy Plumb - Collaborator - University of Bristol
Tim Jones - Collaborator - University of Bristol

Linkages

HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data;Patient Level Index of Multiple Deprivation