Background-The aim of this study was to assess the level of urinary albumin excretion (microalbuminuria), which is associated with increased risk of coronary heart disease and death, in the population. Microalbuminuria has been suggested as an atherosclerotic risk factor. However, the lower cutoff level of urinary albumin excretion is unknown. It is also unknown whether impaired renal function confounds the association. Methods and Results-In the Third Copenhagen City Heart Study in 1992 to 1994, 2762 men and women 30 to 70 years of age underwent a detailed cardiovascular investigation program, including a timed overnight urine sample. The participants were then followed up prospectively by registers until 1999 with respect to coronary heart disease and until 2001 with respect to death. During follow-up, 109 incident cases of coronary heart disease and 276 deaths were traced. A urinary albumin excretion above the upper quartile, ie, 4.8 g/min, was associated with increased risk of coronary heart disease (RR, 2.0; 95% CI, 1.4 to 3.0; PϽ0.001) and death (RR, 1.9; 95% CI, 1.5 to 2.4; PϽ0.001) independently of age, sex, renal creatinine clearance, diabetes mellitus, hypertension, and plasma lipids. Lower levels of urinary albumin excretion were not associated with increased risk. Conclusions-Microalbuminuria, defined as urinary albumin excretion Ͼ4.8 g/min (corresponding to Ϸ6.4 g/min during daytime), is a strong and independent determinant of coronary heart disease and death. Our suggestion is to redefine microalbuminuria accordingly and perform intervention studies.

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Abstract. Klausen KP, Scharling H, Jensen JS (Bispebjerg University Hospital, Copenhagen, Denmark). Very low level of microalbuminuria is associated with increased risk of death in subjects with cardiovascular or cerebrovascular diseases.

Objective: Microalbuminuria and metabolic syndrome are both associated with cardiovascular disease (CVD). The aim of this study was to determine the potential association between numbers of components in the metabolic syndrome, different levels of microalbuminuria and renal function. We also aimed to determine the risk of death and CVD at different levels of microalbuminuria and renal function and numbers of components in the metabolic syndrome.Design: Population-based observational follow-up study Setting: Epidemiological research unit (Copenhagen City Heart Study).Subjects: A total of 2696 men and women, 30-70 years of age.Baseline measures: Urinary albumin excretion (UAE), creatinine clearance and metabolic risk factors were measured in 1992-1994. Main outcome measurements:The participants were followed prospectively by registers until 1999-2000 with respect to CVD, and until 2004 with respect to death. Results:We found a strong association between microalbuminuria and the metabolic syndrome: 2% with none and 18% with five metabolic risk factors had microalbuminuria (P < 0.001). No association between impaired renal function defined as creatinine clearance <60 mL min )1 and the metabolic syndrome was found. Microalbuminuria was associated with increased risk of death and CVD to a similar extend as the metabolic syndrome, irrespective of concomitant presence of metabolic syndrome (RR2; P < 0.001). Impaired renal function was not associated with increased risk of death and CVD in subjects with the metabolic syndrome.Conclusions: Microalbuminuria (UAE >5 lg min )1 ) confers increased risk of death and CVD to a similar extent as the metabolic syndrome.

Abstract-Microalbuminuria has so far been defined as urinary albumin excretion between 20 and 200 g/min (or 15 to 150 g/min overnight). In a recent report, an overnight urinary albumin excretion Ͼ5 g/min was strongly predictive of coronary heart disease and death in the general population. The aim of the present study was to confirm this observation in a population of hypertensive individuals. In The Third Copenhagen City Heart Study in 1992 to 1994, 1734 men and women aged 30 to 70 years with hypertension, but no history of coronary heat disease, delivered a timed overnight urine sample. They were followed-up prospectively by registers until 2000 with respect to coronary heart disease, and until 2004 with respect to death. During follow-up, 123 incident cases of coronary heart disease and 308 deaths were traced. Incident coronary heart disease occurred in 11% of subjects with urinary albumin excretion Ն5 g/min compared with 5% in subjects with urinary albumin excretion Ͻ5 g/min (PϽ0.001). Similarly, the cumulative mortality was 28% versus 13% (PϽ0.001). The relative risks of coronary heart disease and death associated with urinary albumin excretion Ն5 g/min were 2.0 (1.4 to 2.9; PϽ0.001) and 1.9 (1.5 to 2.3; PϽ0.001), respectively, after adjustment for age, sex, blood pressure level, antihypertensive drugs, diabetes, creatinine clearance, smoking, lipoproteins, and body mass index. In conclusion, our study supports the new definition of microalbuminuria as urinary albumin excretion Ͼ5 g/min. In future risk assessment in hypertensive individuals, measurement of microalbuminuria has to be included.

Microalbuminuria (UAE > 5 microg/min) confers increased risk of death and to a similar extent as obesity. This effect is independent of concomitant obesity. We suggest microalbuminuria to be included in health examinations besides measurements of obesity.

In order to study the long-term effect of microalbuminuria on mortality among patients hospitalized with acute myocardial infarction, we followed 125 patients from 1996 to 2000. Exclusion criteria at baseline were renal or urinary tract disease, diabetes mellitus and acute coronary revascularization. At inclusion, urinary albumin/creatinine concentration ratio, height, weight, blood pressure, left ventricle ejection fraction by echocardiography, smoking status, medication, number of acute myocardial infarctions, age and sex were recorded. Deaths were traced in 2000 by means of the Danish Personal Identification Register. Microalbuminuria, defined as a urinary albumin/creatinine concentration ratio above 0.65 mg/mmol, occurred in 52% of the patients and was associated with increased all-cause mortality. Thus, 39% of the patients with microalbuminuria versus only 20% with normoalbuminuria had died within 4 years (p = 0.04). In logistic regression analyses, the odds ratio for death associated with microalbuminuria was 2.5 (1.2–5.6) (p = 0.03), whereas the age-adjusted odds ratio was 1.8 (0.8– 4.2) (p = 0.18). We conclude that the presence of microalbuminuria might be associated with an increased 4-year risk of death among hospitalized patients with myocardial infarction. This hypothesis should be tested in a major population of patients in order to verify the independence from other risk factors including age. Furthermore, we recommend microalbuminuria to be included in future trials in patients with myocardial infarction.

Our study evaluates the long-term effect of microalbuminuria on mortality among patients with acute myocardial infarction. We followed 151 patients from 1996 to 2007 to investigate if microalbuminuria is a risk factor in coronary heart disease. All patients admitted with acute myocardial infarction in 1996 were included. At baseline, we recorded urinary albumin/creatinine concentration ratio, body mass index, blood pressure, left ventricle ejection fraction by echocardiography, smoking status, medication, diabetes, age, and gender. Deaths were traced in 2007 by means of the Danish Personal Identification Register. Microalbuminuria, defined as a urinary albumin/creatinine concentration ratio above 0.65 mg/mmoL, occurred in 50% of the patients and was associated with increased all-cause mortality. Thus, 68% of the patients with microalbuminuria versus 48% of the patients without microalbuminuria had died during the 10 years of follow-up (P=0.04). The crude hazard ratio for death associated with microalbuminuria was 1.78 (CI: 1.18–2.68) (P=0.006), whereas the gender- and age-adjusted hazard ratio was 1.71 (CI: 1.03–2.83) (P=0.04). We concluded that microalbuminuria in hospitalized patients with acute myocardial infarction is prognostic for increased long-term mortality. We recommend measurement of microalbuminuria to be included as a baseline risk factor in patients with acute myocardial infarction and in future trials in patients with coronary heart disease.