ObjectiveIn the present study, we estimated the influence of obstructive sleep apnea (OSA) on the progression of type B intramural hematoma (IMHB). MethodsA total of 127 patients had undergone sleep evaluations and esophageal pressure measurements. The variables associated with aorta-related adverse events and mortality were summarized by logistic regression analysis and Cox proportional hazard models. A competing risk analysis of death was used to estimate aorta- and non–aorta-related mortality. ResultsThe OSA group had a greater aorta-related adverse events rate (46% vs 4%; P < .001). The mean nighttime systolic pressure (odds ratio [OR], 1.24; 95% confidence interval [CI], 1.11-1.38; P < .001) was associated with aorta-related adverse events during the acute phase. Thoracic endovascular aortic repair (hazard ratio [HR], 16.2; 95% CI, 7.68-34.22, P < .001) and mean morning systolic pressure (HR, 1.43; 95% CI, 1.22-1.68; P < .001) were associated with a higher rate of aorta-related adverse events. OSA (HR, 3.19; 95% CI, 2.57-12.15; P < .001) and mean morning systolic pressure (HR, 1.59; 95% CI, 1.27-2.01; P = .002) were significantly associated with aorta-related mortality. Competing risk analysis revealed significantly higher aorta-related mortality in the OSA group (11.8% vs 2.0%; P = .0412). A neutrophil/lymphocyte ratio >3.52 (specificity, 90.2%; sensitivity, 89.5%) and mean platelet volume/platelet ratio >0.049 (specificity, 98.0%; sensitivity, 98.7%) had diagnostic value for detecting OSA in patients with IMHB. ConclusionsThe presence of OSA led to a higher aorta-related adverse event rate and mortality in patients with IMHB. The variables associated with these outcomes included thoracic endovascular aortic repair, mean morning and nighttime systolic pressure, and OSA. The neutrophil/lymphocyte ratio and platelet volume/platelet ratio are valuable for detecting OSA in patients with IMHB.