REN and Hypertension: Although a large number of measurements of phenotypes have been performed in NSPHS, we lack several phenotypes that would have allowed us to investigate relations between protein biomarkers and underlying functional factors contributing to development of disease, such as risk factors for metabolic syndrome33, components of the adrenergic system34 and components involved in the regulation of the renin-angiotensin-aldosterone system35 in relation to blood pressure, pre-hypertension or hypertension.