anticholinergic

For one, it is not a deliriant, nor it is an anticholinergic agent.

Trazodone has a mild side effect profile, but it is an anticholinergic.

Second, these studies lacked information about the dose and duration of anticholinergic use.

Your link says anticholinergic use later in life has been linked to cognitive decline, not that use by young people results in cognitive decline later in life.

Somewhat unsurprising to me. I once accidentally overdosed on an anticholinergic drug, and it was the most unpleasant experience of my life.

My initial thought would be probably not, because anticholinergic drugs work by blocking cholinergic receptors.

This article examines and compares the anticholinergic effects of antihistamine drugs.

I linked to Wikipedia, but I originally read the abstract of a different study, which might have examined diphenhydramine specifically rather than many anticholinergic drugs.

First, current anticholinergic use was ascertained at study entry and periodically during follow-up only by conducting a medication inventory.

Finally, these studies did not take into account that certain anticholinergics are used to manage insomnia and depression, prodromal conditions that can be seen in early but undiagnosed dementia, leading to protopathic bias.

That other study specifically noted the use of anticholinergics in controlling certain prodromal symptoms of dementia which leads back to the causation/correlation uncertainty and the desperate need to resolve the uncertainty.