Chest x‐ray aortic size and risk of death and cardiovascular disease in older Chinese: Guangzhou biobank cohort study

BACKGROUND: Chest radiograph can independently predict adverse outcomes in outpatients. We examined the associations of aortic knob width (AKW), ascending aortic length (AAL), and ascending aortic width (AAW) from chest x-ray with death and cardiovascular events in adults aged 50 and above. METHODS: Participants without cardiovascular disease were included from the Guangzhou Biobank Cohort Study (2003-2008). AKW, AAL, and AAW were indexed by body surface area. Aortic enlargement was defined using sex- and age-specific thresholds, calculated as the average value plus 1.96 multiplied by the standard deviation (SD). The associations of AKW, AAL, and AAW indices with all-cause and cause-specific mortality (cardiovascular and cancer), and incident nonfatal and fatal cardiovascular events, were examined through multivariate Cox regressions. Logistic regressions were performed to determine risk factors for aortic enlargement. RESULTS: Among 27,047 participants (mean age 62 years ± 7 years SD), there were 6977 deaths and 6478 cardiovascular events over an average follow-up period of 16.3 years. Each SD increase in AKW index was associated with a higher risk of all-cause mortality, cardiovascular mortality, and cardiovascular events, with hazard ratios (95% confidence interval [CI]) of 1.13 (1.11-1.16), 1.20 (1.15-1.25), and 1.11 (1.08-1.14), respectively. Similar findings were observed regarding the AAL and AAW indices. Hypertension was a strong risk factor for enlarged AKW (odds ratio 2.52, 95% CI 2.17-2.93), AAL (1.95, 1.63-2.32), and AAW (1.80, 1.56-2.09), respectively. CONCLUSIONS: Thoracic aortic parameters measured through an accessible, cheap, and safe chest radiograph were associated with higher risks of death and cardiovascular events. Hypertension should be managed.