54 Can microalbuminuria identify silent “pancardiac” target organ damage in a non-diabetic primary prevention population?
Background Microalbuminuria is associated with increased cardiovascular mortality and is a marker of generalised vascular dysfunction. We sought to investigate whether micoalbuminuria identified the presence of silent “pancardiac” target organ damage (TOD) ie, left ventricular hypertrophy (LVH), systolic dysfunction (LVSD), diastolic dysfunction (LVDD), left atrial enlargement (LAE) or silent myocardial ischaemia in a non-diabetic primary prevention population.
Methods Two hundred and sixty-three asymptomatic individuals without diabetes or previous cardiovascular disease on primary preventive therapy were prospectively recruited. Each participant underwent a comprehensive echocardiographic examination for the assessment of LV mass, LV systolic and diastolic function, and left atrial volume while the presence of inducible ischaemia was assessed by dobutamine stress echocardiography or dipyridamole myocardial perfusion imaging. A spot urine sample was analysed for microalbuminuria and urinary creatinine by a trained laboratory technician blinded to clinical or echocardiographic data. Microalbuminuria was defined as urinary albumin to creatinine ratio of ≥2.5 mg/mmol in males and ≥3.5 mg/mmol in females.
Results Out of 263 participants (Mean age 64±6.3 years, 57% males) 89 (33.8%) had evidence of silent cardiac TOD (29.7% LVH, 16.7% LAE, 17.1% LVDD, 6.8% LVSD and 6.1% Ischaemia). The prevalence of cardiac TOD was significantly higher (53% vs 29%, p=0.002) among those with microalbuminuria than those without. In multivariate analysis adjusted for age, gender, hypertension and dyslipidemia, presence of microalbuminuria was an independent predictor of cardiac TOD with an adjusted HR of 2.54 (95% CI, 1.2 to 4.4, p=0.005). The utility of UACR in discriminating between those with or without cardiac TOD was assessed by receiver operating characteristic analysis but the area under curve was only 0.61±0.04, p=0.003.
Conclusion Microalbuminuria is an independent predictor of silent “pancardiac” target organ damage in a non-diabetic primary prevention population. Presence of microalbuminuria may help to identify those primary prevention patients who are at a particularly higher risk.