If smoked, not surprising. Another typed of smoked leaf (tobacco) has this association too.
The same study did find that smoked marijuana induces the same changes in blood that smoking cigarettes do, and those changes lead to CVD, cancers, etc in tobacco smokers.
edit: This is what I'm thinking of: https://pubmed.ncbi.nlm.nih.gov/40434782/
Most of the time, if you read the headline for a study, and instantly have a thought that would make the entire study's results pointless, it's very very probable the study authors had that thought too and mitigated it. It's their job.