Sodium intake affects urinary albumin excretion especially in overweight subjects

OBJECTIVES: To examine the relationship between sodium intake and urinary albumin excretion, being an established risk marker for later cardiovascular morbidity and mortality. DESIGN: Cross-sectional cohort study using linear regression analysis. Setting. University hospital outpatient clinic. SUBJECTS: A cohort drawn from the general population, consisting of 7850 subjects 28-75 years of age, all inhabitants of the city of Groningen, the Netherlands. The cohort is enriched for the presence of subjects with elevated urinary albumin concentration. RESULTS: The results show a positive relationship between dietary sodium intake and urinary albumin excretion. The association was independent of other cardiovascular risk factors (such as sex, age, blood pressure, body mass index (BMI), waist-to-hip ratio, serum cholesterol, plasma glucose and smoking) and other food constituents (calcium, potassium and protein). The relationship between sodium intake and urinary albumin excretion was steeper in subjects with a higher BMI compared with a lower BMI. CONCLUSIONS: Sodium intake is positively related to urinary albumin excretion. This relation is more pronounced in subjects with a higher BMI. These results suggest that high sodium intake may unfavourably influences cardiovascular prognosis especially in overweight and obese subjects.