Re: Fluoroquinolone use and risk of aortic aneurysm and dissection: nationwide cohort study
We appreciate the effort Drs Pasternak and others have put into carefully researching the important topic of the risk of aortic aneurysm associated with fluoroquinolone use. This is an important topic that is relevant to physicians in many specialties.
The results of this analysis have been widely quoted and so we feel that the authors should clarify their statistical methods. In the article they state that 64 cases of aneurysm were seen on the exposed group and 40 in the control group. Since both groups contained 360,088 participants. The excess rate is 24 cases or 67 per million not 82 as stated. The printed confidence interval is 15-181 which is not symmetric with 82.
For the cumulative incidence calculation for fluoroquinolone there were 64 cases per 360088 which is 1.7 x10-4 not 2.0 as written. The amoxicillin group had 40 per 360088 or 1.1 x10-4. This was written as 1.2.
We hope that the statistical calculations can be verified and corrected if needed. We would leave it to others to determine the clinical significance of an excess of 67 cases per million exposures to the fluoroquinolones.
Competing interests: No competing interests