Author + information
- Martin H. Ruwald⁎ (, )
- Morten Lock Hansen, MD, PhD,
- Michael Vinther, MD and
- Gunnar H. Gislason, MD, PhD
- ↵⁎University of Rochester Medical Center, Heart Research Follow-up Program, 265 Crittenden Boulevard, Rochester, New York 14642
We read with interest the comments on our study (1) by Drs. Barbic and colleagues and Dr. Bonzi and colleagues.
Dr. Barbic and colleagues got the impression from our paper that patients 25 to 44 years of age had twice the risk of death than those older than 75 years of age. This misunderstanding is related to the hazard ratios mentioned in our study in which the hazard ratio in the 25 to 44 age group is 2.29, and that for those older than 75 years is 0.98. This is, of course, not the case, and the mentioned hazard ratios are given for “syncope” compared with “controls” of the same age group; thus, healthy individuals in the 25 to 44 age group with syncope have twice the risk of the corresponding control group without syncope. The relative relationship between the age groups and the cumulative incidence of death can be seen in Figure 1, where it is evident that with advanced age, the risk of death is much higher.
Dr. Barbic and colleagues propose an intriguing hypothesis that the increased mortality rate in these otherwise healthy patients with syncope may be caused by work-related accidents. We share their thoughts and are currently in the process of investigating the impact of syncope on subsequent accidents, falls, and accidents involving motor vehicles or large machinery compared with a matched control population by linking the data provided in this study with a database containing all data on accidents reported to the Danish medical system. Hopefully these analyses will provide data that could be useful for an evidence-based approach to guidelines on the use of heavy machinery and motorized vehicles after episodes of syncope.
Dr. Bonzi and colleagues whether our definition of low-risk patients was appropriate and states that syncope most of the time is the first manifestation of several diseases in healthy people. We do not agree that this has been shown before in the referred literature. We agree that the risk stratification developed is based on many other factors than comorbidities, but the registries used for our study do not include this information. Nevertheless, we find that our study provides valid contemporary data and prognosis on a very large population of “healthy” patients with syncope. We also want to emphasize that our definition of healthy individuals included that they were free of taking medications. Bonzi et al. state that the results on 1-year mortality were inconclusive, but we disagree with his interpretation because we clearly demonstrate that in patients 25 to 74 years of age, “healthy or low-risk” people with syncope have a significantly increased 1-year mortality rate compared with matched controls. Finally, Bonzi et al. requests the data re-analyzed on patients who were only seen in the emergency department. Our study combined those discharged from the emergency department with those discharged after admission. We did, however, also look into those patients who were discharged from the emergency department only, and the results were consistent with the overall results. As you noted, there was a typographical error in the online edition of the paper in the confidence intervals of the age group younger than 25 years of age; this was corrected in the print version.
- American College of Cardiology Foundation