Letter: Carotid Artery Disease Severity and Systemic Inflammation

Dear Editor,

We read with interest the paper by Altiparmak et al ¹ entitled “The Influence of Smoking and Systemic Inflammation on Carotid Artery Disease: A Cross-Sectional Analysis of Stenosis, Plaque Surface Characteristics.” We congratulate the authors. We would like to make some comments.

This retrospective study included 822 consecutive patients with carotid artery stenosis (CAS) (≥50% luminal narrowing, based on the North American Symptomatic Carotid Endarterectomy Trial criteria) who presented to a stroke center over a 10-year period. There was a significant relationship between the Pan-immune-inflammatory value (PIV) and the degree of plaque instability and stenosis. Blood samples were collected at the time of presentation to the stroke center. ¹ We believe this could be a significant limitation. Whether patients present with asymptomatic ischemic attacks, transient ischemic attacks, or severe stroke symptoms may affect inflammatory values. Studies have demonstrated dynamic changes in neutrophils, lymphocytes, and platelets following acute events.^2,3

In their study, the authors recorded patients’ use of antithrombotic and cholesterol-lowering medications. However, the potential impact of these variables on the study was not evaluated. Could antithrombotic agent use have affected PIV values? Or could neutrophil or lymphocyte counts have been affected by the anti-inflammatory effects of statins? Statins are known to have effects on neutrophils and lymphocytes. ⁴ Furthermore, platelet counts may be affected by antiplatelet therapy. ⁵

Finally, the study demonstrated the relationship between atherosclerotic CAS and inflammatory markers readily available from routine blood tests. ¹ However, we believe that the lack of precise knowledge of atherosclerotic status in other arterial circulation systems is a significant limitation. Coronary artery disease and peripheral artery disease were presented as categorical variables in the study. ¹ However, imaging studies clearly demonstrating these systems were not available for all patients. A recent study demonstrated a relationship between PIV values and abdominal aortic calcification. ⁶ Similarly, another study investigating the relationship between PIV and atherosclerosis demonstrated a significant relationship between the severity of coronary artery disease and PIV. ⁷