Normal individuals demonstrate a decline in renal function over time. Above the age of 30, this amounts to an average decrease of 0.7 to 0.9 mL/min in the glomerular filtration rate (GFR) per year . Once renal injury has occurred, independent of etiology, the decline in GFR can be accelerated by hypertension, proteinuria, and possibly by dyslipidemia [2-4].
The rate of decline in GFR in established chronic kidney disease (CKD) can be decelerated with early intervention. Perhaps the most successful intervention is the reduction of elevated blood pressure , and there may be an added benefit to using angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers particularly in those with significant proteinuria. (See "Antihypertensive therapy and progression of nondiabetic chronic kidney disease in adults".)
In animals, dyslipidemia is causally associated with glomerular injury, leading to the development of glomerulosclerosis [6-8]. However, this does not correlate with human studies in which lipid-rich conditions, such as familial hyperlipidemia, do not seem to lead to clinically-relevant renal injury. Perhaps this is due to earlier development of significant cardiovascular disease or targeted interventional therapy. On the other hand, once CKD has been established, small series have demonstrated an association between progression of renal disease and hyperlipidemia .
Secondary analyses of data on subsets of patients with decreased kidney function recruited into several trials of hypertensive and/or dyslipidemic cohorts have helped to clarify some of these issues. However, in interpreting these post-hoc analyses, it is important to exercise considerable caution as renal dysfunction was not the primary objective of the studies and significant inaccuracies may accrue as a result of subanalysis, with increased risk of type I errors. In addition, the evaluation of renal function in these post-hoc analyses typically is done using formulaic manipulation of plasma creatinine levels, with all of the obvious short-comings of this methodology.
The evidence linking dyslipidemia management with statins to the decline in renal function will be presented in this topic review. Additional reasons for the use of statins in those with renal disease, including an overview of its possible benefits in decreasing the risk of adverse cardiovascular outcomes, will also be presented briefly. Overviews of the use of statins in patients without renal failure are presented separately. (See "Statins: Actions, side effects, and administration" and "Mechanisms of benefit of lipid-lowering drugs in patients with coronary heart disease".)