Measurable Urinary Albumin Predicts Cardiovascular Risk among Normoalbuminuric Patients with Type 2 Diabetes
Journal of the American Society of Nephrology, 08/31/2012
Exclusive author commentary
Ruggenenti P et al. – Among normoalbuminuric patients with type 2 diabetes, any degree of measurable albuminuria bears significant cardiovascular risk. The association with risk is continuous but is lost with early angiotensin–converting enzyme inhibitor therapy.
Dr. Giuseppe Remuzzi (09/04/2012) comments:
We found that in individuals with type 2 diabetes, any degree of measurable urinary albumin excretion — even in what is considered the normal range — increases their risk of experiencing heart problems. This risk may be reduced by early treatment with ACE inhibitors, antihypertensive medications that inhibit the renin angiotensin system. These findings could help identify patients who should be treated with cardioprotective medications. Some patients with type 2 diabetes experience kidney problems that cause them to excrete increased amounts of the protein albumin in their urine, a condition called albuminuria. These patients have a considerably higher risk of developing heart problems — such as heart attacks, strokes, and heart failure — than other diabetic patients and people in the general population, who are “normoalbuminuric,” with urinary albumin excretion levels of less than 20 ?g/min. We wondered if any level of albumin excretion — for example at a level that is the upper range of what is considered normal — might increase a diabetic patient’s risk of developing heart problems. This is a major health issue since patients with normoalbuminuria account for at least 90% of the diabetic population. Through an extension of a clinical trial originally designed for other purposes, we evaluated the relationship between albumin excretion levels and heart problems in 1,208 normoalbuminuric patients with type 2 diabetes who were followed for an average of 9.2 years. We found that any degree of measurable albumin excretion bore significant heart risks: 1. For each 1 ?g/min in albumin excretion at the start of the study, there was a progressive incremental risk of experiencing heart problems during follow-up. 2. Even albuminuria of 1-2 ?g/min significantly associated with increased risk compared with albuminuria <1 ?g/min. When we looked only at the subgroup of patients who took ACE inhibitors from the start of the study and throughout the follow-up period, we found no link between albumin excretion levels and heart risks. This suggests that ACE inhibitors have heart-protective properties that may benefit diabetic patients with albuminuria and normoalbuminuria alike. Future clinical trials are needed to identify levels of albumin excretion above which such cardioprotective therapy is beneficial. Study co-authors include Piero Ruggenenti MD, Esteban Porrini MD, Nicola Motterlini StatSciD, Annalisa Perna, StatSciD, Aneliya Parvanova Ilieva MD, Ilian Petrov Iliev MD, Alessandro Roberto Dodesini MD, Roberto Trevisan MD, Antonio Bossi MD, Giuseppe Sampietro MD, Enrica Capitoni RN, Flavio Gaspari PhD, Nadia Rubis RN, Bogdan Ene-Iordache EngD.