Association between cumulative anticholinergic burden and dementia risk in older adults: An integrative literature review

Dementia represents one of the main challenges for global public health, and exposure to medications with anticholinergic activity is considered a possible modifiable risk factor for cognitive decline. This study aimed to analyze the scientific evidence regarding the association between cumulative anticholinergic burden and the risk of developing dementia in older adults. This is an integrative literature review, conducted according to the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. The search was conducted in the PubMed, SciELO, LILACS and Scopus databases, using descriptors related to anticholinergic burden, dementia, Alzheimer's disease and older adults. After the eligibility criteria were applied, five studies comprised the final sample, including observational studies, literature reviews and a methodological study. The results demonstrated a consistent association between greater cumulative exposure to anticholinergic medications and an increased risk of cognitive impairment, Alzheimer's disease and dementia. In addition, a dose-response relationship between anticholinergic burden and dementia risk was observed, as well as an association with a higher rate of cortical atrophy. The use of instruments to measure anticholinergic burden proved relevant for identifying individuals with greater vulnerability to adverse cognitive outcomes. Although the evidence points to a consistent association, methodological limitations related to the heterogeneity of the studies and the predominance of observational designs remain. It is concluded that anticholinergic burden constitutes an important potentially modifiable factor associated with the development of cognitive decline and dementia, reinforcing the need for careful assessment of pharmacotherapy, especially in older adults receiving polypharmacy.