Effects of Diabetes and Microalbuminuria on Heart Disease

---

The impact of type 2 diabetes and microalbuminuria on future cardiovascular events in patients with clinically manifest vascular disease from the Second Manifestations of ARTerial disease (SMART) study, by Soedamah-Muthu and colleagues. Diabetic Medicine 25:51–57, 2008.

What is the problem and what is known about it so far?

Type 2 diabetes and microalbuminuria (small amounts of protein in the urine) are important risk factors for cardiovascular (heart and blood vessel) disease. However, it is unknown whether these two conditions both increase the chances of having a cardiovascular event (heart attack, stroke, or related condition) in people who are already at high risk.

Why did researchers do this particular study?

The researchers wanted to find out whether the presence of type 2 diabetes, urine protein, or both increases the likelihood of someone at risk for cardiovascular disease having a heart attack, stroke, or related event.

Who was studied?

The study included nearly 4,000 adult patients, some with diabetes, microalbuminuria, or both, and some without one or either condition. All participants had known blood vessel disease and had taken part in an ongoing Dutch blood vessel disease study between 1996 and 2006.

How was the study done?

Data on personal traits and medical history were taken from the original study, and patients were asked to complete a questionnaire twice a year for 4 years about their hospital admissions and outpatient medical visits. Any information related to cardiovascular events was confirmed. The data were analyzed to identify links between type 2 diabetes, microalbuminuria, and cardiovascular events.

What did the researchers find?

Both type 2 diabetes and microalbuminuria increased the risk of new heart attacks, stokes, or related events. Patients who had neither diabetes nor microalbuminuria had the lowest risk of cardiovascular events. The risk increased for those who had diabetes. It increased still more for those who had microalbuminuria, whether alone or in combination with type 2 diabetes. However, the effect of microalbuminuria was only apparent in patients without diabetes, and the effect of diabetes was only apparent in patients without microalbuminuria.

What were the limitations of the study?

Although it has been suggested that all three conditions—cardiovascular disease, type 2 diabetes, and microalbuminuria—have common root causes, this study could not examine that possibility because no data were available from the period before microalbuminuria or type 2 diabetes developed. In addition, the study could not account for microalbuminuria or type 2 diabetes that developed after the start of the study because these conditions were measured only at the beginning of the 4-year study period.

What are the implications of the study?

Type 2 diabetes and albuminuria are both important risk factors for future heart and blood vessel disease in patients already at high risk. Although they are interrelated, their effects seem to be independent. Future research will need to explore possible shared underlying causes of these conditions and to more fully explain their links. In the meantime, it is important to target both conditions for treatment as early as possible to prevent cardiovascular disease.

FOR MORE INFORMATION

Diabetes, heart disease and stroke

Taking care of your heart

Diabetes complications