Individuals who have both elevated C-reactive protein levels and large carotid plaques have the highest risk of myocardial infarction and ischemic stroke, according to the PhD thesis of Agnethe Eltoft.

MAIN RESULTS:

1. The inflammatory marker C-reactive protein is linked to carotid plaque.
2. Levels of interleukin-6 are associated with progression of carotid plaque.
3. The combination of carotic plaque and high levels of C-reactive protein seem to increase the risk of stroke and myocardial infarction

THESIS DEFENCE:

Thesis: C-reactive protein and other circulating biomarkers in carotid atherosclerosis and cardiovascular disease
Candidate: Agnethe Eltoft
Time: November 7, 2018 at 12:15
Place: UiT The Arctic University of Norway, MH-Vest: Auditorium Cortex
Link to university website (in Norwegian)

SUMMARY:

(1) Higher levels of the inflammatory marker C-reactive protein (CRP) in blood is associated with increased odds of having plaque in the carotid arteries, according to Eltoft’s first article. The association was significant also after adjustment for the traditional cardivascular risk factors. However, CRP levels at the first survey were not linked to increased risk of plaque progression or development before the next survey.

The study includes ultrasound assessments of the right carotid artery in 6503 middle-aged men and women who participated in the Tromsø 4 Study in 1994. 4730 of them also took part in Tromsø 5 in 2001, and 2917 in Tromsø 6 in 2007.

(2) Interleukin-6 could be a marker of unstable carotid plaque, shows the second study of the thesis. Eltoft and co-workers analyzed 28 biomarkers in blood from 703 Tromsø Study participants, and looked at how they related to progression of plaque between two surveys. Only interleukin-6 was associated with plaque progression after adjustments for cardiovascular risk factors and the other measured biomarkers.

(3) Individuals who have both carotid plaque and high levels of CRP are at increased risk of myocardial infarction and stroke. Including the combination of plaque and inflammation improves prediction of cardiovascular disease beyond traditional risk models.

This study includes more than 10 000 participants from the Tromsø Study. High CRP levels and carotid total plaque are were also independently linked to increased risk of cardiovascular disease on their own, but these association were weaker than when the two factors were combined.

REFERENCES:

(1) Eltoft, A., Arntzen, K. A., Hansen, J. B., Wilsgaard, T., Mathiesen, E. B., & Johnsen, S. H. (2017). C-reactive protein in atherosclerosis–A risk marker but not a causal factor? A 13-year population-based longitudinal study: The Tromsø study. Atherosclerosis, 263, 293-300.

(2) Eltoft, A., Arntzen, K. A., Wilsgaard, T., Mathiesen, E. B., & Johnsen, S. H. (2018). Interleukin-6 Is An Independent Predictor Of Progressive Atherosclerosis In The Carotid Artery: The Tromsø Study. Atherosclerosis, 271, 1-8.

(3) Eltoft, A., Arntzen, K. A., Wilsgaard, T., Hansen, J. B., Mathiesen, E. B., & Johnsen, S. H. (2018). Joint Effect Of Carotid Plaque And C‐Reactive Protein On First‐Ever Ischemic Stroke And Myocardial Infarction?. Journal of the American Heart Association, 7(11), e008951.