Anticholinergic Burden and Risk of Seizures in People with Dementia: Self-Controlled Case Series
Published in SSRN Pre-prints, 2022
Background: Because the risk of the anticholinergic burden on the risk of seizure in people with dementia is scarce; we aimed to investigate the incidence rate ratio (IRR) of seizure following anticholinergic burden in people with dementia aged 60 years or older in Hong Kong (HK).
Methods: In this self-controlled case series, we identified people with dementia, prescribing anticholinergic medications and had incident or recurrent seizures (outcomes) between 2004 and 2019 using electronic healthcare records in HK. Any anticholinergic medications (except anticonvulsant and anxiolytics) quantified by 1) summative Anticholinergic Cognitive Burden (ACB) Score of 1, 2 and ≥ 3; and 2) the number of anticholinergic classes used in combination. A 7-day pre-treatment period was defined. We compared the IRR of outcomes for different treatments to non-treatment periods using a conditional logistic regression model adjusting age and seasonality.
Findings: 1220 and 494 patients with incident and recurrent seizures were identified, respectively. Compared with the non-treatment period, risk of incident seizure was higher on day 0 (adjusted IRR: 8.47, 95% Confidence interval: 5.02-14.28) and during the pre-treatment period (4.17, 3.10-5.60), followed by ACB scores of ≥ 3 (1.52, 1.22-1.90), ACB score of 2 (1.41, 1.08-1.83) and ACB score of 1 (1.22, 1.01-1.47) during exposure periods. This is consistent with recurrent seizures and subgroup and sensitivity analyses.
Interpretation: Anticholinergic medications were not the main contributor to the risk of seizures. Multidisciplinary strategies for preventing seizures should consider reducing both the anticholinergic burden and managing comorbidities in people with dementia.
Recommended citation: Qin, S. X., Lau, J. C. H., Warren-Gash, C., Luo, H., Liu, K. Y., Howard, R., Lau, G. K. K., Wong, I. C. K., & Chui, C. S. L. (2022). Anticholinergic Burden and Risk of Seizures in People with Dementia: Self-Controlled Case Series. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.4270302
Download Paper