In geriatric patients, delirium symptoms are related to the anticholinergic burden

Anticholinergic drugs are widely prescribed for elderly patients and could induce several neuropsychological disorders, especially delirium. The aim of the present study was to evaluate the relationship between anticholinergic burden and delirium symptoms.

A total of 102 patients aged over 75 years (86.3 ± 5.8 years, 53 women and 49 men) hospitalized in a geriatric medicine department were included in this prospective study. Anticholinergic burden was assessed by classifying drug use into three levels (low, medium or high). An overall, weighted score was established. Delirium symptoms were measured with the Confusion Assessment Method on days 1, 3, 5, 8, 15 and 21. Covariates studied were comorbidities (Charlson), health status, activities of daily living, nutrition (albumin), cognition, length of stay and mortality.

A total of 51.6% of the patients were taking anticholinergic drugs at home (2.13 ± 1.34). Length of stay was 14.5 ± 9.9 days. Prevalence of delirium symptoms ranged on days between 34.8 and 60%. Anticholinergic burden was correlated with the appearance of delirium symptoms. Delirium symptoms were associated with greater mortality (16.1 and 3.7 % in patients with and without delirium symptoms; P = 0.049), a longer hospital stay (18.09 ± 11.34 vs 11.75 ± 7.80 days, P = 0.001), greater dependence on discharge (activities of daily living score: 1.57 ± 1.56 vs 3.41 ± 1.45, P < 0.0001) and worse health status on discharge (5.3 ± 2.7 vs 7.0 ± 1.7, P = 0.0008).

Anticholinergic burden appears as a risk factor for both delirium symptoms and mortality. Prevention of delirium symptoms requires its reduction.