Recently increased anticholinergic burden is associated with an increased risk of acute cardiovascular events in older adults, according to a study of Taiwan’s National Health Insurance Research Database. “A greater increase in anticholinergic burden was associated with a higher risk of acute cardiovascular events,” the authors conclude.
The case-case/time-control study incorporated a case-crossover design and a control crossover design consisting of future cases. The study included 317,446 adults aged 65 years who were admitted to hospital because of an incident acute cardiovascular event (myocardial infarction, strokes, arrhythmias, conduction disorders, and cardiovascular death) in 2011–2018. The anticholinergic burden was measured for each participant by adding up the anticholinergic scores for individual drugs using the Anticholinergic Cognitive Burden Scale (classified in 3 levels: 0, 1–2, and ≥3 points).
“The crossover analyses included 248,579 current cases,” the authors write. “Participants’ average age on the index date was 78.4 years (standard deviation 0.01), and 53.4% were men. The most frequently prescribed drugs with anticholinergic activity were antihistamines (68.9%), gastrointestinal antispasmodics (40.9%), and diuretics (33.8%). Among patients with varying levels of anticholinergic burden in different periods, more patients carried higher levels of anticholinergic burden during hazard periods than during reference periods. For example, 17,603 current cases had 1-2 points of anticholinergic burden in the hazard period with 0 points in the reference period, while 8,507 current cases had 0 points in the hazard period and 1-2 points in the reference period. In the comparison of 1-2 points versus 0 points of anticholinergic burden, the odds ratio was 1.86 (95% confidence interval 1.83 to 1.90) in the case crossover analysis and 1.35 (1.33 to 1.38) in the control crossover analysis, which yielded a case-case-time-control odds ratio of 1.38 (1.34 to 1.42). Similar results were found in the comparison of ≥3 versus 0 points (2.03, 1.98 to 2.09) and ≥3 versus 1-2 points (1.48, 1.44 to 1.52). The findings remained consistent throughout a series of sensitivity analyses (eg, cut-off points for anticholinergic burden categories were redefined and different scales were used to measure anticholinergic burden).”
Editorial: “Previous epidemiological studies indicate that about 20-50% of older adults regularly receive drugs with anticholinergic effects, and one third to one half of the drugs commonly prescribed to older adults exhibit potential anticholinergic activity, ” editorialists write. “Therefore, recognising the anticholinergic burden and its potential negative impacts on older people is important clinically. [This study] contributes to a growing body of evidence by establishing an association between recently increased anticholinergic burden and a heightened risk of acute cardiovascular events, including myocardial infarction, stroke, arrhythmia, and cardiovascular death in older adults.”