Thoracic aortic calcification is associated with incident stroke in the general population in addition to established risk factors

Aims: The aorta is a major source of cerebral thromboembolism, but its role in stroke pathogenesis is not well understood due to its poor accessibility for non-invasive imaging. We examined whether thoracic aortic calcification (TAC), a marker of aortic plaque load, is associated with stroke in addition to established risk factors.

Methods and results: A total of 3930 subjects from the population-based Heinz Nixdorf Recall study (45-75 years; 47.1% men) without previous stroke, coronary heart disease, or myocardial infarction were evaluated for incident stroke events over 109.0 ± 23.3 months. Cox proportional hazards regressions were used to examine associations with stroke of TAC in addition to established risk factors (age, sex, systolic blood pressure, LDL, HDL, diabetes, and smoking) and coronary artery calcification (CAC). 101 incident strokes occurred during the follow-up period. Subjects suffering a stroke had significantly higher TAC values at baseline than the remaining subjects (median = 83.1 [Q1;Q3 = 4.7;472.9] vs. 15.7 [0.0;117.1]; P < 0.001). In a multivariable Cox proportional hazards regression, log(TAC + 1) (hazards ratio [HR] = 1.09 [95% confidence interval = 1.00-1.19]; P = 0.044) was associated with stroke in addition to established risk factors. Further analyses revealed that log(DTAC + 1), i.e. calcification of the descending aorta (1.11 [1.02-1.20]; P = 0.016), but not log(ATAC + 1), i.e. calcification of the ascending aorta (1.02 [0.93-1.11]; P = 0.713), was associated with stroke. The HR for log(TAC + 1) decreased to 1.06 (0.97-1.16; P = 0.202), when log(CAC + 1) was also inserted into multivariable analyses.

Conclusion: Calcification of the thoracic aorta, more specifically its descending segment, is associated with incident stroke in addition to established risk factors. CAC outperforms aortic calcification as a stroke predictor.