Who is most at risk? Generally speaking, older adults and people with underlying conditions such as diabetes, high cholesterol or pre-existing heart issues are at the greatest risk, experts said. That’s because their cardiovascular systems tend to be more fragile, and marijuana further stresses the heart.

At the most, it seems more honest to suggest that smoking marijuana with preexisting cardiovascular issues may be uniquely harmful. But even within that narrowly defined community I reckon it would be a tall task to isolate the effects of marijuana as a smoking gun (heh) with so many other potentially contributing factors.