Cystatin C, left ventricular hypertrophy, and diastolic dysfunction: Data from The Heart and Soul Study

Background: Impaired kidney function, as measured by serum cystatin C, is associated with risk of incident heart failure. Whether cystatin C is associated with preclinical cardiac structural abnormalities is unknown. We evaluate whether cystatin C is associated with left ventricular hypertrophy, diastolic dysfunction, and systolic dysfunction among 818 outpatients with coronary artery disease who were free of clinical heart failure. Methods and Results: The 818 study participants were categorized into quartiles based on serum cystatin C concentrations, with <= 0.91 mg/L constituting the lowest quartile (1) and >= 1.28 mg/L constituting the highest (IV). Left ventricular hypertrophy (left ventricular mass index >90 g/m(2) by truncated ellipsoid method), diastolic dysfunction (impaired relaxation, pseudo-normal, or restrictive filling patterns) and systolic dysfunction (left ventricular ejection fraction <= 50%) were determined by echocardiography. Left ventricular hypertrophy was present in 68% of participants in quartile IV, compared with 44% of those in quartile I (adjusted odds ratio [OR] 2.17; 95% confidence interval [CI] 1.34 to 3.52; P = .002). Diastolic dysfunction was present in 52% of participants in quartile IV, compared with 24% of those in quartile I (adjusted OR 1.79; 95% CI 1.04 to 3.11; P = .04). Systolic dysfunction was present in 12% of those in quartile IV, compared with 6% of those in quartile I (adjusted OR 1.83; 95% CI 0.75 to 4.46; P = .15). Conclusion: Higher cystatin C concentrations are strongly associated with left ventricular hypertrophy and diastolic dysfunction in outpatients with coronary artery disease and without heart failure.