Cardiovascular Disease Risk High in RA Patients

The NCEP (National Cholesterol Education Program) Adult Treatment Panel III criteria for metabolic syndrome include the following, and three of the five must be present for a diagnosis of metabolic syndrome:

• Waist circumference: >40.2 inches in men; >34.6 inches in women
• Triglycerides: >150 mg/dL
• HDL cholesterol: <40 mg/dL in men; <50 mg/dL in women
• Blood pressure: >130/85 mm Hg
• Fasting plasma glucose: >110 mg/dL

Several factors are associated with insulin resistance in patients with RA, according to Dr. Giles, who is assistant professor of medicine in the division of rheumatology at Johns Hopkins University in Baltimore. These factors include macronutrient excess, often accompanied by less physical activity; obesity, whether overt or preferential partitioning; inflammation, with more RA-derived cytokines; and glucocorticoid use.

Other metabolic syndrome criteria also tend to be over-represented in RA: waist girth, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia.⁶

Predictors of insulin resistance in RA include increasing current prednisone use, decreasing HDL cholesterol, and increasing truncal fat mass as measured by a dual-energy X-ray absorptiometry scan. Rheumatoid factor seropositivity and cumulative prednisone dose have been linked with higher visceral fat in patients with RA, he said.

There is “no current evidence that any particular pharmacologic agent decreases cardiovascular risk by reversing insulin resistance in any rheumatic disease,” Dr. Giles said. Instead, primary efforts to reduce insulin resistance should focus on fat reduction, given the central role of visceral fat in insulin resistance.

“Maintaining a healthy body composition should be emphasized even early in disease, along with constant reappraisal of the need to continue glucocorticoids,” he said.

Kathy Holliman is a medical journalist based in New Jersey.

References

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