Certain blood pressure drugs show promise in reducing dementia.

Anticholinergic drugs that act on the central nervous system should be avoided when treating people diagnosed with dementia for incontinence and other bladder conditions, a new study confirms.

Investigators looked at health outcomes in 540 patients with dementia receiving these drugs for bladder conditions. First, they determined which of these drugs are more likely to involve the central nervous system — and therefore the brain — using a measurement of anticholinergic effects on cognition. This so-called high anticholinergic burden has been linked to cognitive decline, delirium, dizziness and confusion, falls and hospitalizations. 

The urinary drugs tolterodine and oxybutynin have high anticholinergic effects on cognition scores and were associated with a 55% increased mortality risk. This was compared with darifenacin, fesoterodine, trospium, mirabegron and solifenacin, which had low or no effect on the central nervous system, reported Delia Bishara, PharmD, of King’s College London. 

The researchers also looked at cognitive decline over the 24-month period around diagnosis, using participants’ scores on the Mini-Mental State Examination. Decline was only detectable in the high central anticholinergic group, they said. But there was no significant difference in cognitive trajectories between the high and low/no anticholinergic bladder drug groups, Bishara and colleagues discovered. 

There also was no increase in emergency hospitalization risk linked to the drugs with high central anticholinergic burden.

“Urinary drugs with high central anticholinergic burden cause more harm than those acting peripherally and should be avoided in people with dementia,” the researchers concluded. The study did not answer the question of whether centrally acting anticholinergic agents in general worsen dementia outcomes, and they propose more study on this matter.

The study was published in JAMDA.