"Results: Common vaccines were associated with an increased risk of dementia (OR, 1.38 [95% CI, 1.36-1.40]), compared with no exposure."
Conclusions: Common vaccines were not associated with a decreased risk of dementia. Unmeasured confounding and detection bias likely accounted for the observed increased risk.
The “attenuated” in this case means “weakened the case for”.
Or, in other words, we found a correlation without finding any causation.