Microalbuminuria may identify high-risk metabolic syndrome patients

9 September 2010

MedWire News: Microalbuminuria can help identify high-risk nondiabetic patients with the metabolic syndrome who could benefit from intensive medical therapy and lifestyle changes, US researchers claim.

They found that the presence of microalbuminuria among individuals with the metabolic syndrome was associated with an increased inflammatory state and risk for subclinical atherosclerosis, and was “highly predictive” of cardiovascular outcomes.

The team from Wayne State University in Detroit, Michigan, says: “Microalbuminuria represents a simple, but useful, clinical tool that might help identify a high-risk subgroup of nondiabetic persons with the metabolic syndrome.”

Luis Afonso and colleagues conducted a post-hoc analysis of 5809 nondiabetic US adults in the Multiethnic Study of Atherosclerosis, who were aged 45 to 84 years, and did not initially have cardiovascular disease.

The metabolic syndrome was identified in 30.2% of participants according to International Diabetes Federation criteria, used as it incorporates race-specific cutoffs for abdominal obesity.

Microalbuminuria, defined as a urine albumin/creatinine ratio of 17 to 250 mg/g in men or 25 to 355 mg/g in women, was more common among individuals with than without the metabolic syndrome, at 14.2% versus 7.7%, respectively.

During a mean follow-up of 4.7 years, there were 226 all-cause cardiovascular disease events, 166 all-cause coronary heart disease events, 168 all-cause deaths, 79 myocardial infarctions, 69 strokes, and 71 cases of new-onset congestive heart failure.

People with the metabolic syndrome and microalbuminuria were more likely than those with the metabolic syndrome only to be in the top 25% of a variety of systemic inflammation markers and measures of subclinical atherosclerosis.

They also had significantly increased hazard ratios for all-cause cardiovascular disease events, myocardial infarction, stroke, and new-onset congestive heart failure, at 1.70, 2.20, 3.26, and 2.49, respectively.

However, the authors report in the American Journal of Cardiology that there were no significant differences for all-cause coronary heart disease events or all-cause mortality.

Nonetheless, they conclude: “Our findings suggest that the presence of microalbuminuria in nondiabetic patients with the metabolic syndrome identifies a high-risk subgroup that might benefit from more aggressive risk factor management, including dietary, lifestyle modification, and intensification of medical treatment of hypertension and dyslipidemia.”

Am J Cardiol 2010; Advance online publication