Which drug classes have been associated with cognitive impairment in longitudinal studies of polypharmacy?

• A. Antihypertensives and statins
• B. Vaccines
• C. Antibiotics
• D. Psychotropics and anticholinergics

Answer: (D)

The key idea is how certain medications contribute to cognitive decline when multiple drugs are used over time. Drugs with anticholinergic effects block acetylcholine, a neurotransmitter essential for learning and memory. In older adults, higher cumulative exposure to anticholinergic medications is repeatedly linked in longitudinal studies with faster cognitive decline, greater risk of mild cognitive impairment or dementia, and more episodes of delirium that can recur.

Psychotropic drugs—such as antidepressants with anticholinergic properties, antipsychotics, and sedative-hypnotics like benzodiazepines—also impair cognition. They can cause prolonged sedation, slowed processing, attention deficits, and memory problems, especially with long-term or higher-dose use. The combination of these two classes tends to produce the strongest and most consistent associations with cognitive impairment across time in polypharmacy research.

Other options—vaccines, antibiotics, or antihypertensives and statins—haven’t shown the same robust, consistent links to long-term cognitive impairment in longitudinal polypharmacy studies.