Salford Kidney Study

The Salford Kidney Study (SKS, REC reference 15/NW/0818) commenced in 2002. It is one of the largest and longest running international renal cohorts. The cohort was initially known as CRISIS (Chronic Renal Insufficiency Standards Implementation Study). In 2016 it was renamed as SKS. The study has underpinned many epidemiologic and biomarker studies in non-dialysis CKD. Participants in the study have a mean follow-up of 5 years.

New referrals to the Salford Royal Renal Service are screened for recruitment to SKS, and other patients are recruited from existing follow-up clinics. The patients are managed according to national and international guidelines, representing real-world clinical practice. Patients are reviewed annually at routine visits until discharge, withdrawal from the study or death. Around 200-300 patients per year join the study.

 

The SKS has facilitated bio-sample and detailed phenotypic and outcome data collection in almost 4000 prospectively followed patients The consent procedure enables external collaboration for clinical data sharing, plasma and serum biomarker analysis and genomic studies. All phenotypic, laboratory and adjudicated event data is available and there are > 65,000 plasma/serum aliquots stored at -80oC with DNA stored off site.

The main cohort consists of non-dialysis CKD patients (3600) and more recently sub-collections of haemodialysis, peritoneal dialysis and kidney transplant patients have been added. Historically, most of the patients enrolled into SKS were from a White British background with only 3% from ethnic minority communities, but recent efforts have focused on recruitment of patients more representative of the department’s demographic footprint. Patients enrolled into the SKS represent all the main kidney disease aetiologies: Diabetic nephropathy (20%), glomerulonephritis (18%), hypertension/RVD(18%), chronic pyelonephritis (12%) and autosomal dominant polycystic kidney disease (ADPKD, 6%) with 30% of SKS patients having an ‘unknown CKD’ phenotype.

Other disease specific databases

The department also maintains the following databases that facilitate real-world epidemiologic research:

• Atherosclerotic renovascular disease (ARVD): the most comprehensive international database of > 1,000 patients, from which many studies have been derived.
• Covid-related research includes acute kidney injury, Covid epidemiology and seroconversion after vaccination in immunosuppressed patients.
• Kidney transplant: detailed epidemiologic data from almost 1000 patients transplanted since year 2000.
• Glomerulonephritis: individual disease databases with comprehensive data from patients with IgA nephropathy, membranous nephropathy, FSGS and vasculitis.