Anticholinergic burden and 1-year mortality among older patients discharged from acute care hospital

Aim: The association between anticholinergic burden and mortality is controversial. We aimed to investigate whether the anticholinergic cognitive burden (ACB) score predicts 1-year mortality in older patients discharged from acute care hospitals. Methods: Our series consisted of 807 hospitalized patients aged ≥65years. Patients were followed up for 12months after discharge. All-cause mortality was the outcome of the study. The ACB score at discharge (0, 1, ≥2) and increasing ACB score from admission to discharge (no increase, +1, +2 or more) were calculated and used as exposure variables. Cox proportional hazards models adjusted for potential confounders were used for the analysis. Interactions between the ACB score and cognitive impairment or history of falls were also investigated. Results: During the follow-up period, 177 out of 807 participants (21.9%) died. After adjusting for potential confounders, a discharge ACB score of ≥2 (HR 1.69, 95% CI 1.09-2.65) was significantly associated with the outcome, whereas the association between increasing ACB score of +2 or more and mortality was weaker (HR 1.30, 95% CI 0.95-1.92). The interaction between the ACB score at discharge or increasing ACB score and cognitive impairment was statistically significant (P =0.003 and P =0.004, respectively), whereas that between the ACB score and falls was not. Conclusions: The ACB score at discharge and, to a lesser extent, an increasing ACB score during hospital stay are associated with an increased risk of 1-year mortality in older patients discharged from hospital. Such an association is stronger among patients with cognitive impairment.