Researchers tracked patients and found newer anticoagulants slowed cognitive decline
Newer anticoagulants slowed the pace of cognitive decline in patients living with both atrial fibrillation and Alzheimer's disease, outperforming an older blood-thinning drug and no anticoagulation at all.
A Swedish nationwide study published in the European Heart Journal drew on the country's cognitive and dementia registry to track 7,308 patients diagnosed with Alzheimer's or mixed dementia who also had a prior atrial fibrillation diagnosis.
Researchers sorted patients by whether they took a non-vitamin K oral anticoagulant, the older drug warfarin, or no anticoagulant, then measured cognitive change over five years using the Mini-Mental State Examination, an assessment scored from 0 to 30 in which higher marks indicate better function.
Patients on the newer drugs recorded a decline of roughly 0.2 points per year slower than the other two groups, according to the study, a difference the authors described as "significantly slower" once cognitive scores were compared across the full follow-up period.
Maria Eriksdotter, the professor at Karolinska Institutet who led the research, said in a news release carried by CTV News that the treatment "could have a positive effect on cognition," pointing to improved blood flow and reduced small-scale brain damage as possible mechanisms.
Nanbo Zhu, a researcher in the institute's Department of Neurobiology, Care Sciences and Society, characterised the year-over-year effect as modest but potentially consequential, telling CTV News that "over a longer period even such an effect could influence how cognitive function develops."
Beyond cognition, both anticoagulant types were tied to lower rates of death, stroke, and blood clots than no treatment, the European Heart Journal study reported, with the stronger associations attached to the newer drugs.
Compared with no anticoagulation, non-vitamin K users showed a 5.9 percent lower mortality risk and a 4.7 percent lower risk of ischaemic stroke or systemic embolism at three years.
Patients on the newer medications also carried a lower fracture risk, while warfarin users saw a higher rate of major bleeding, according to the research.
The authors flagged several limitations, CTV News noted.
Because the work was observational, researchers could not confirm the newer drugs directly caused the slower decline, and lifestyle or treatment factors may explain part of the gap.
It was also unknown whether some patients switched medications during the study, the researchers acknowledged.
The study disclosed that Eriksdotter has served as a consultant in one-off engagements with, or has lectured at events sponsored by, several drug companies, CTV News reported.
The research team focused on Alzheimer's and mixed dementia cases and recommended further study of other dementia subtypes.
