In This Issue of Archives of Internal Medicine

T he effect of cystatin C on successful aging was examined in the Cardiovascular Health Study. Successful aging was defined as remainingfreeofcardiovasculardisease, cancer, and chronic obstructive pulmonary disease, with intact physical and cognitive functioning. An adjusted accelerated failure time model was used to evaluate the percentage reduction in successful life years by levelof cystatinC.Themeancystatin C level and estimated glomerular filtration rate were 1.06 mg/L and 78mL/min/1.73m,respectively.The adjustedpercentagereductioninsuccessful life years in the highest quartile in comparison with the lowest quartile of cystatin C was 27% (95% confidence interval, 11%-39%). A higher cystatin C level, even within a range of relatively normal kidney function,wasassociated with unsuccessful aging. See page 147