Do outpatient ophthalmologic procedures increase risk for acute MI?

Ophthalmologic procedures performed in an outpatient setting do not seem to heighten the risk for acute myocardial infarction (AMI), a study has shown.

This population-based nationwide study examined the short-term risk for AMI associated with ophthalmologic procedures among first-time patients with AMI aged ≥40 years, identified through inpatient registries and linked to outpatient surgical procedures in Norway (2008 to 2014) and Sweden (2001 to 2014), respectively.

The investigators compared exposure to ophthalmologic procedures in the 0‒7 days prior to AMI diagnosis (hazard period) with days 29‒36 before AMI (control period), using self-matching to estimate the relative risk for an AMI episode the week after the procedure.

Using conditional logistic regression, the investigators calculated the odds ratios (ORs) with 95 percent confidence intervals (CIs). Patients without a procedure of interest during either the hazard or control period were excluded.

A total of 806 patients with AMI met the eligibility criteria. The likelihood of AMI was lower in the week following an ophthalmologic procedure than during the control week (OR, 0.83, 95 percent CI, 0.75‒0.91). When analyses were stratified by surgery subtype, anaesthesia (local or general), duration, invasiveness (low, intermediate, or high), patient's age (<65 years or ≥65 years), or comorbidity (none vs any), evidence did not show a heightened risk for AMI.

The study was limited by potential bias from time-varying confounders between the hazard and the control periods.