BackgroundCurrent reporting guidelines do not call for standardised declaration of follow-up completeness, although study validity depends on the representativeness of measured outcomes. The Follow-Up Index (FUI) describes follow-up completeness at a given study end date as ratio between the investigated and the potential follow-up period. The association between FUI and the accuracy of survival-estimates was investigated.MethodsFUI and Kaplan-Meier estimates were calculated twice for 1207 consecutive patients undergoing aortic repair during an 11-year period: in a scenario A the population’s clinical routine follow-up data (available from a prospective registry) was analysed conventionally. For the control scenario B, an independent survey was completed at the predefined study end. To determine the relation between FUI and the accuracy of study findings, discrepancies between scenarios regarding FUI, follow-up duration and cumulative survival-estimates were evaluated using multivariate analyses.ResultsScenario A noted 89 deaths (7.4%) during a mean considered follow-up of 30±28months. Scenario B, although analysing the same study period, detected 304 deaths (25.2%, P<0.001) as it scrutinized the complete follow-up period (49±32months). FUI (0.57±0.35 versus 1.00±0, P<0.001) and cumulative survival estimates (78.7% versus 50.7%, P<0.001) differed significantly between scenarios, suggesting that incomplete follow-up information led to underestimation of mortality. Degree of follow-up completeness (i.e. FUI-quartiles and FUI-intervals) correlated directly with accuracy of study findings: underestimation of long-term mortality increased almost linearly by 30% with every 0.1 drop in FUI (adjusted HR 1.30; 95%-CI 1.24;1.36, P<0.001).ConclusionFollow-up completeness is a pre-requisite for reliable outcome assessment and should be declared systematically. FUI represents a simple measure suited as reporting standard. Evidence lacking such information must be challenged as potentially flawed by selection bias.

Background: Aortic syndromes (AS), including aortic dissection (AD), intramural hematoma (IMH) and penetrating aortic ulcer (PAU), carry significant acute and long-term morbidity and mortality. However, the contemporary incidence and outcomes of AS are unknown. Methods and Results: We utilized the Rochester Epidemiology Project record linkage system to identify all Olmsted County, Minnesota, residents with AS (1995–2015). Diagnostic imaging, medical records, and death certificates were reviewed to confirm the diagnosis and AS subtype. Age- and sex-adjusted incidence rates were estimated using annual county-level census data. Survival for patients with AS was compared to age- and sex-matched controls using Cox regression to adjust for comorbid conditions. We identified 133 patients with AS (77-AD, 21-IMH, and 35-PAU). Average age was 71.8 years (SD 14.1) and 57% were male. The age- and sex-adjusted incidence was 7.7 per 100,000 person-years, was higher for males than females (10.2 vs. 5.7 per 100,000 person-years), and increased with age. Among subtypes, the incidence of AD was highest (4.4 per 100,000 person-years), while the incidence of PAU and IMH were lower (2.1 and 1.2 per 100,000 person-years). Overall, the incidence of AS was stable over time (p trend=.33), although the incidence of PAU appeared to increase from 0.6 to 2.6 per 100,000 person-years (p=.008) with variability over the study interval. Patients with AS had more than twice the mortality rate at 5, 10, and 20 years when compared to population-based controls (5, 10 and 20-year mortality 39%, 57%, 91% versus 18%, 41%, and 66%; overall adjusted mortality HR=2.1, p<0.001). Survival was lower than expected up to 90 days after AS diagnosis and did not differ significantly by subtype or by 5-year strata of diagnosis. Conclusions: Overall, the incidence of AD and IMH has remained stable since 1995, despite the decline noted for other cardiovascular disease. AS confers increased early and long-term mortality that has not changed. These data highlight the need to improve long term care to impact the prognosis of this patient group.