Preserved glomerular filtration rate in older people. A population-based study in the Southern Cone of Latin America

Introduction: Kidneys are affected by the aging process, usually suffering a progressive glomerular filtration rate (GFR) reduction of around 1 ml/year as of 30 years of age. Nevertheless, few older subjects show a stable GFR over time. This phenomenon has not been exhaustively studied, and even less in the Southern Cone. Aim: The aim was to estimate the prevalence of preserved GFR in a representative sample of older adults and explore the association between cardiovascular risk factors and preserved GFR in older individuals. Methods: We used data from a cross-sectional survey of a random sample of 1571 participants aged 65–74 years from 4 cities of the Southern Cone. We describe the prevalence of eGFR ?80 ml/min/1.73 m2 and sociodemographic, biological, behavioral risk factors and medication use.  Backward stepwise logistic regression analysis was used to study the effect of cardiovascular risk factors on eGFR ?80 ml/min. Results: In this a study 962 had an eGFR >80 ml/min/1.73 m2 and 154 were healthy adults (Prevalence= 17.01 % [95%CI 14.5%; 19.9%]). The median eGFR in the full sample was 85.53 ml/min/1.73 m² (IQR: 73.12-91.26). The prevalence of eGFR >80 ml/min/1.73 m2 was higher among men. Overall, older adults with no cardiovascular risk factors and eGFR >80 ml/min/1.73 m2 were predominantly men and showed a lower prevalence of dyslipidemia.  Conclusion: In the present study was documented that there was 17% of healthy older individuals who have preserved glomerular filtration rate (eGFR > 80 ml/min/1.73 m 2) despite their advanced age.