@article {873, title = {Cystatin C and incident peripheral arterial disease events in the elderly: results from the Cardiovascular Health Study.}, journal = {Arch Intern Med}, volume = {165}, year = {2005}, month = {2005 Dec 12-26}, pages = {2666-70}, abstract = {

BACKGROUND: The association of cystatin C, a novel marker of renal function, with risk for developing complications related to peripheral arterial disease (PAD) has not been examined.

METHODS: We evaluated the hypothesis that a high cystatin C concentration is independently associated with future PAD events among 4025 participants in the Cardiovascular Health Study who underwent serum cystatin C measurement at the 1992-1993 visit and who did not have PAD at baseline. The association of cystatin C quintiles with time to first lower-extremity PAD procedure (bypass surgery, angioplasty, or amputation) was evaluated using multivariable proportional hazards models. Secondary analyses were conducted using quintiles of serum creatinine level and estimated glomerular filtration rate (eGFR).

RESULTS: The annualized risk of undergoing a procedure for PAD was 0.43\% per year among participants in the highest cystatin C quintile (>1.27 mg/L) compared with 0.21\% per year or less in all other quintiles. After multivariable adjustment for known risk factors for PAD, elevated cystatin C levels remained associated with the outcome (hazard ratio, 2.5 for highest vs lowest quintile of cystatin C, 95\% confidence interval, 1.2-5.1). The highest quintiles of serum creatinine level and eGFR were not associated with future PAD events in either unadjusted or adjusted analyses.

CONCLUSION: Elevated concentrations of cystatin C were independently predictive of incident PAD events among community-dwelling elderly patients.

}, keywords = {Aged, Cohort Studies, Cystatin C, Cystatins, Female, Health Surveys, Humans, Longitudinal Studies, Male, Peripheral Vascular Diseases, Predictive Value of Tests, Risk Factors, ROC Curve, United States}, issn = {0003-9926}, doi = {10.1001/archinte.165.22.2666}, author = {O{\textquoteright}Hare, Ann M and Newman, Anne B and Katz, Ronit and Fried, Linda F and Stehman-Breen, Catherine O and Seliger, Stephen L and Siscovick, David S and Shlipak, Michael G} } @article {827, title = {Cystatin C concentration as a risk factor for heart failure in older adults.}, journal = {Ann Intern Med}, volume = {142}, year = {2005}, month = {2005 Apr 05}, pages = {497-505}, abstract = {

BACKGROUND: Previous studies that evaluated the association of kidney function with incident heart failure may be limited by the insensitivity of serum creatinine concentration for detecting abnormal kidney function.

OBJECTIVE: To compare serum concentrations of cystatin C (a novel marker of kidney function) and creatinine as predictors of incident heart failure.

DESIGN: Observational study based on measurement of serum cystatin C from frozen sera obtained at the 1992-1993 visit of the Cardiovascular Health Study. Follow-up occurred every 6 months.

SETTING: Adults 65 years of age or older from 4 communities in the United States.

PARTICIPANTS: 4384 persons without previous heart failure who had measurements of serum cystatin C and serum creatinine.

MEASUREMENTS: Incident heart failure.

RESULTS: The mean (+/-SD) serum concentrations of cystatin C and creatinine were 82 +/- 25 nmol/L (1.10 +/- 0.33 mg/L) and 89 +/- 34 micromol/L (1.01 +/- 0.39 mg/dL), respectively. During a median follow-up of 8.3 years (maximum, 9.1 years), 763 (17\%) participants developed heart failure. After adjustment for demographic factors, traditional and novel cardiovascular risk factors, cardiovascular disease status, and medication use, sequential quintiles of cystatin C concentration were associated with a stepwise increased risk for heart failure in Cox proportional hazards models (hazard ratios, 1.0 [reference], 1.30 [95\% CI, 0.96 to 1.75], 1.44 [CI, 1.07 to 1.94], 1.58 [CI, 1.18 to 2.12], and 2.16 [CI, 1.61 to 2.91]). In contrast, quintiles of serum creatinine concentration were not associated with risk for heart failure in adjusted analysis (hazard ratios, 1.0 [reference], 0.77 [CI, 0.59 to 1.01], 0.85 [CI, 0.64 to 1.13], 0.97 [CI, 0.72 to 1.29], and 1.14 [CI, 0.87 to 1.49]).

LIMITATIONS: The mechanism by which cystatin C concentration predicts risk for heart failure remains unclear.

CONCLUSIONS: The cystatin C concentration is an independent risk factor for heart failure in older adults and appears to provide a better measure of risk assessment than the serum creatinine concentration. *For a full list of participating Cardiovascular Health Study investigators and institutions, see http://www.chs-nhlbi.org.

}, keywords = {Aged, Biomarkers, Creatinine, Cystatin C, Cystatins, Female, Follow-Up Studies, Glomerular Filtration Rate, Heart Failure, Humans, Incidence, Kidney, Kidney Function Tests, Male, Risk Factors, United States}, issn = {1539-3704}, doi = {10.7326/0003-4819-142-7-200504050-00008}, author = {Sarnak, Mark J and Katz, Ronit and Stehman-Breen, Catherine O and Fried, Linda F and Jenny, Nancy Swords and Psaty, Bruce M and Newman, Anne B and Siscovick, David and Shlipak, Michael G} }