Building on prior research that indicated that the use of antiepileptic therapies was associated with a greater risk of dementia in older adults, Finnish and German researchers used two data sets to test this correlation.
The Finnish data set was part of the nationwide register-based MEDALZ study, which includes all 70,718 persons diagnosed with Alzheimer’s in Finland in 2005-2011 and their 282,862 controls.
German researchers studied the association between antiepileptic therapy use and dementia in a sample from a large German statutory health insurance provider, which included 20,325 persons diagnosed with dementia in 2004-2011, and their 81,300 controls.
Researchers compared the risk of dementia and antiepileptic medications both with and without known cognitive adverse effects. They differentiated between long-term and occasional antiepileptic use, while also looking at a possible dose-response relation.
Results showed that continuous use of antiepileptic medications for more than one year was linked to a 15% increase in the risk of Alzheimer’s in the Finnish dataset, and a 30% increased risk of dementia in the German data set.
Specifically, using therapies that are known to impair cognitive function correlated with a 20% greater risk of Alzheimer’s and a 60% greater risk of dementia. The most frequently used medications with known cognitive effects include primidone, phenytoin, carbamazepine, clonazepam, and valproate. The greatest risk for Alzheimer’s and dementia was observed with valproate.
In contrast, medications with no known cognitive adverse effects, which include oxcarbazepine, vigabatrin, tiagabine, lamotrigine, gabapentin, levetiracetam, pregabalin, and lacosamide, did not correlate with an increased dementia risk.
Data also revealed that the higher the dose of an antiepileptic therapy that can impair cognitive function, the higher the risk of dementia.
“More research should be conducted into the long-term cognitive effects of these drugs, especially among older people,” Heidi Taipale, PhD, the study’s first author from the University of Eastern Finland, said in a press release.
“Our findings highlight the importance of possible long-term adverse cognitive effects of [antiepileptic medications] in older adults,” the researchers wrote in the study, highlighting the need for large clinical trials to confirm these results.