Day-of-week variability in the occurrence and outcome of aortic diseases

Background & Objectives In analogy with other cardiovascular events, acute aortic diseases do not randomly occur over time but show definite temporal variations. Previous studies showed an increased frequency of onset of cardiovascular events on Monday, whereas weekends seem to be characterized by a higher mortality, both for myocardial infarction and stroke. The aim of this study, based on the large number of cases of the database of the Emilia-Romagna region of Italy, was to confirm the existence of a weekly pattern in aortic dissection and rupture, and evaluate possible differences in weekdays compared to weekends.Subjects & Methods We considered all cases of hospital admissions recorded at the database of the Emilia-Romagna region of Italy (years 2000–2006), with the following ICD-9-CM codes: 441, aortic aneurysm and dissection; 441.0, dissection of the aorta; 441.00, unspecified site; 441.01, thoracic; 441.02, abdominal; 441.03, thoracoabdominal; 441.1, thoracic aneurysm, ruptured; 441.3, abdominal aneurysm, ruptured; 441.5, aortic aneurysm of unspecif. site; 441.6, thoracoabdominal aneurysm, ruptured. Cases were categorized by day of hospitalization, and c2 goodness of fit was used for statistical analysis for total population, subgroups by gender and age, presence or not of arterial hypertension, and type of acute event, e.g., dissection or rupture. Results The total population consisted of 4615 cases (77% males, mean age 70 ± 13 years, 59.8% dissections). A weekly pattern, with a decreasing frequency from Monday to Sunday, was shown for total cases (p < 0.0001), dissection (p < 0.0001), but not rupture (p = NS). A similar pattern was observed in hypertensive (dissection: p < 0.0001; rupture: p = 0.044) and normotensive subjects (dissection: p < 0.0001; rupture: p = NS). Fatal cases showed an opposite trend, with a Sunday peak and a Monday trough. Fatal cases showed a significant prevalence on weekends (dissection: 22.8% vs 15.5%, p< .0001; rupture: 47.9% vs 40.6%, p = 0.003). Discussion Monday seems to be a critical day for the occurrence of cardiovascular diseases. It is possible that stress of commencing weekly working activities, morning surge in blood pressure, and unfavorable biochemical metabolic status could play a role. Weekends have been shown to be characterized by a higher frequency of fatal cases. This has been shown for myocardial infarction and stroke, and this can be explained, at least in part, by the reduction of availability of medical staffing and ancillary support. Further studies should be addressed to investigate this important issue.