To the Editor: Dr Meier and colleagues1 interpreted their findings as consistent with an
antibiotic effect against vascular infections that may have a causal role
in myocardial infarction, but they were careful to emphasize that their data
do not support the current use of antibiotics to prevent AMI.
In contrast, some evidence suggests that antibiotics might, under some
circumstances, be associated with triggering AMI. A case-control study (980
cases, 3136 controls) of antibiotic use in the 6-month period prior to hospitalization
for acute vascular events (mainly myocardial infarction and stroke) using
an administrative database including 160,194 enrollees of a Wisconsin health
maintenance organization found an overall "protective" effect of antibiotic
use (18.7% of cases, 22.1% of controls; P = .02).2 However, antibiotic use in the month prior to hospitalization
was "protective" only for adults aged 70 years or older (odds ratio [OR],
0.6; 95% confidence interval [CI], 0.5-0.8), "neutral" for adults aged 60-69
years (OR, 1.1; 95% CI, 0.8-1.5), and a "risk factor" for adults younger than
60 years (OR, 1.6; 95% CI, 1.2-2.0). The authors hypothesized that 1 possible
explanation for this age-related risk profile was that antibiotics produced
unstable plaque leading to acute vascular events in younger patients with
"soft" plaque containing C pneumoniae, as is the
case for the Jarisch-Herxheimer reaction following penicillin treatment for
syphilis, which can be disastrous if the lesions are located in coronary arteries.3