MedWire News: African-American patients with hypertension have higher levels of D-dimer than their White counterparts, say US researchers.

“Measurement of D-dimer levels may be helpful in assessing the risk for cardiovascular disease, especially in African Americans,” suggest Iftikhar Kullo (Mayo Clinic, Rochester, Minnesota) and co-workers.

“Whether lowering the elevated levels of D-dimer in susceptible population groups by lifestyle/pharmacologic means will lower cardiovascular morbidity and mortality will need confirmation by randomized controlled trials,” they write.

The team measured plasma D-dimer levels in 933 African-American and 821 non-Hispanic White patients with hypertension. They also collected information on gender, age, body mass index, total and high-density lipoprotein cholesterol, diabetes, history of smoking, exercise and alcohol, kidney function, medication use, and C-reactive protein (CRP) levels.

D-dimer levels were on average significantly higher in African-American men and women with hypertension than in non-Hispanic White men and women (256 vs 190 ng/ml and 290 vs 225 ng/ml, respectively).

African-American patients continued to have higher D-dimer levels after adjusting for age, cardiovascular risk factors, medication use, and lifestyle, and after taking into consideration estimated glomerular filtration rate and C-CRP, the team reports in the Journal of Thrombosis and Haemostasis.

“Unmeasured environmental and genetic factors may partially contribute to the ethnic difference in plasma D-dimer levels,” Kullo et al suggest.

“Further studies are needed to elucidate the pathophysiologic basis for this observation.”

They also recommend further research to determine whether elevated D-dimer levels in African Americans could explain the increased cardiovascular disease risk in this population.

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