β-blockers prevent the compensatory sympathetic surge triggered by hypoglycemia. As such, symptoms characteristic of the sympathetic state are blunted.
-While the above results are concerning, I do not view them as an absolute contraindication to
β-blocker use. Rather, they inform my management. Prior to therapy initiation, I identify individuals at high risk for hypoglycemia (insulin dependence, the elderly, brittle diabetics) and monitor them more closely. I instruct them to check their glucose frequently during β-blocker initiation and insulin dose titration; I also inquire about the above during follow up visits.
It is unclear if the study was blinded. Since it
was conducted in those on insulin mono-therapy, it may not apply to those on oral agents.
While a non-selective
β-blocker was used, only limited evidence suggests β1 selective agents (metoprolol, atenolol) avoid these adverse events.