Background: 

To quantify the association between anticholinergic drug use (burden or load) and cognitive function (MMSE), blood pressure and the presence of anticholinergic side effects.

Methods:

The medical records of 182 aged care home residents in the Perth metropolitan area, Western Australia were reviewed retrospectively to obtain demographic data, past and current medical problems, history of use of agents with anticholinergic effects and the following medication-related problems: cognitive impairment (as determined by Mini Mental State Examination {MMSE} score), blood pressure elevation and the presence of anticholinergic side effects. Anticholinergic load was calculated, and the relationship between the anticholinergic load and the presence of anticholinergic side effects was assessed using stepwise multiple regression and multiple logistic regression analysis.

Results:

Increasing anticholinergic load was associated with the presence of peripheral anticholinergic side effects including hypertension (AOR=1.53), dry mouth (AOR=1.38), dry eyes (AOR=1.30), constipation (AOR=1.24) and urinary hesitancy (AOR=1.21) (all p values ≤0.05). The anticholinergic load was not associated with blurred vision (p=0.084) and Mini Mental State Examination score decline (p=0.142).

Conclusions:

The anticholinergic load was associated with statistically significantly increased risk of peripheral anticholinergic adverse effects in older aged care residents, however not with cognitive decline.