Aims: Moderate-to-severe chronic renal failure is an established risk factor for cardiovascular disease and mortality. However, most studies have been performed in selected populations and the impact of very small decrements of renal function on long-term cardiac morbidity and mortality has not yet been established. Also, the cut-off level of glomerular filtration rate (GFR) from which cardiovascular risk increases has not exactly been established. This study wants to address these questions.
Methods and results: Ten year follow-up of a representative population-based cohort comprised 8913 randomly selected, apparently healthy participants. Participants were randomly drawn from Belgian voting lists. Cardiovascular risk factors were noted. Serum creatinine values were corrected to isotope dilution mass spectrometry standard, and GFR was calculated using the recently modified 'modification of diet in renal disease' equation. Participants were followed for 10 years, and cause-specific death was registered by analysis of death certificates. The probability to die from all causes or from cardiovascular causes during the 10 year follow-up period increased in each quartile of GFR, even after correction for different other comorbid conditions.
Conclusion: Even mild renal failure is an independent risk factor for cardiovascular mortality within 10 years in an apparently healthy unselected population. This detrimental effect starts already at a relatively high GFR of 90 mL/min/1.73 m2 and remains present after correction for other established cardiovascular risk factors.