BACKGROUND: Chronic kidney disease (CKD) affects up to 16% of the adult 
population and is associated with significant morbidity and mortality. People at 
highest risk from progressive CKD are defined by a sustained decline in 
estimated glomerular filtration rate (eGFR) and/or the presence of significant 
albuminuria/proteinuria and/or more advanced CKD. Accurate mapping of the 
bio-clinical determinants of this group will enable improved risk stratification 
and direct the development of better targeted management for people with CKD.
METHODS/DESIGN: The Renal Impairment In Secondary Care study is a prospective, 
observational cohort study, patients with CKD 4 and 5 or CKD 3 and either 
accelerated progression and/or proteinuria who are managed in secondary care are 
eligible to participate. Participants undergo a detailed bio-clinical assessment 
that includes measures of vascular health, periodontal health, quality of life 
and socio-economic status, clinical assessment and collection of samples for 
biomarker analysis. The assessments take place at baseline, and at six, 18, 36, 
60 and 120 months; the outcomes of interest include cardiovascular events, 
progression to end stage kidney disease and death.
DISCUSSION: The determinants of progression of chronic kidney disease are not 
fully understood though there are a number of proposed risk factors for 
progression (both traditional and novel). This study will provide a detailed 
bio-clinical phenotype of patients with high-risk chronic kidney disease (high 
risk of both progression and cardiovascular events) and will repeatedly assess 
them over a prolonged follow up period. Recruitment commenced in Autumn 2010 and 
will provide many outputs that will add to the evidence base for progressive 
chronic kidney disease.