Cause-specific mortality of type B aortic dissection and assessment of competing risks of mortality

Abstract

Objective: Natural history studies of type B aortic dissection (TBAD) commonly report all-cause mortality. Our aim was to determine cause-specific mortality in TBAD and to evaluate the clinical characteristics associated with aorta-related and nonaorta-related mortality.Methods: Clinical and administrative records were reviewed for patients with acute TBAD between 1995 and 2017. Demographics, comorbidities, presentation, and initial imaging findings were abstracted. Cause of death was ascertained through a multimodality approach using electronic health records, obituaries, social media, Social Security Death Index, and state mortality records. Causes of death were classified as aorta related, nonaorta related, or unknown. A Fine-Gray multivariate competing risk regression model for subdistribution hazard ratio was employed to analyze the association of clinical characteristics with aorta-related and nonaorta-related mortality.Results: A total of 275 individuals met inclusion criteria (61.1 6 13.7 years, 70.9% male, 68% white). Mean survival after discharge was 6.3 6 4.7 years. Completeness of follow-up Clark C index was 0.87. All-cause mortality was 50.2% (n ¼ 138; mean age, 70.1 6 14.6 years) including an in-hospital mortality of 8.4%. Cause-specific mortality was aorta related, nonaorta related, and unknown in 51%, 43%, and 6%, respectively. Compared with patients with nonaorta-related mortality, patients with aorta-related mortality were younger at acute TBAD (69.5 6 11.2 years vs 61.6 6 15.5 years; P ¼ .001), underwent more descending thoracic aortic repairs (19.4% vs 45.8%; P ¼ .002), and had a shorter survival duration (5.7 6 3.9 vs 3.4 6 4.5 years; P ¼ .002). There was clear variation in cause of death by each decade of life, with higher aortarelated mortality among those younger than 50 years and older than 70 years and a stepwise increase in nonaortarelated mortality with each increasing decade (P < .001). All-cause mortality at 1 year, 3 years, and 10 years was 15%, 24%, and 57%, respectively. After accounting for competing risks, the cumulative incidence of aorta-related mortality at 1 year, 3 years, and 10 years was 8.9%, 16.5%, and 27.2%, respectively, and that of nonaorta-related mortality was 2.7%, 7.2%, and 29%, respectively. A maximum descending thoracic aortic diameter >4 cm was associated with an increase in hazard of aorta-related mortality by 84% (subdistribution hazard ratio, 1.84; 95% confidence interval, 1.03-3.28) on multivariate competing risk regression analysis.Conclusions: TBAD is associated with high 10-year mortality. Those at risk for aorta-related mortality have a clinical phenotype different from that of individuals at risk for nonaorta-related mortality. This information is important for building risk prediction models that account for competing mortality risks and to direct optimal and individualized surgical and medical management of TBAD.

Elevated Admission Cardiac Troponin I Predicts Adverse Outcomes of Acute Type B Aortic Dissection after Endovascular Treatment

“…In Li et al’s study ( 21 ), the cut-off value of high-sensitivity cardiac troponin T for in-hospital death in aTAAD patients was 0.042, which was higher than 0.014. In our study, the major cause of death in TBAD patients the first year after TEVAR was aortic-related mortality (69.7%), which was consistent with that of Hysa et al’s study ( 22 ). In this context, the cut-off value of cTnI 0.029 may predict 1-year aortic-related mortality after TEVAR.…”

Initial Thoracic Endovascular Aortic Repair vs Medical Therapy for Acute Uncomplicated Type B Aortic Dissection

“…Mortality rates following uTBAD have previously been reported to approach 30% at 3 to 5 years, but we found 5-year mortality of 44.5%, which may, in part, reflect the older age of the cohort as well as complete outcome ascertainment. We also found hospitalization rates that were higher than previously reported primarily in single-institution or institution-linked registries, highlighting the limitations of institution-centered analyses .…”

Risk Factors for Thoracic Aortic Dissection

“…Sex differences in AAD have received attention due to higher in-hospital or short-term mortality in women with TAD, while both type A and B AADs show approximately twice as frequently in men [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ]. Several studies revealed a later age of AAD onset in females compared with males, and more pharmacotherapy and aortic rupture prior to intervention in women are likely the cause of the early outcome difference [ 15 , 19 , 22 ].…”