February 27, 2012 (Hamilton, Ontario, Canada) — A new post hoc analysis of the ONTARGET and TRANSCEND trials has shown that atrial fibrillation (AF) is linked with an increased risk of cognitive and functional decline, regardless of whether or not the AF sufferers also had a stroke .
"Our results demonstrate an association between atrial fibrillation at baseline or during the relatively short follow-up of five years and very strong outcomes: new dementia, the need for help in performing daily activities, and admission to long-term-care facilities. We are talking about a major loss of independence, which is clearly evident and also present in those patients who did not have any episode of stroke," lead author Dr Irene Marzona (Mario Negri Research Institute for Pharmacological Research, Milan, Italy) told heartwire .
"This is the first time this has been shown clearly in a prospective study," she added.
And she believes that although the findings will require confirmation in future studies, they are robust enough to indicate that measures of cognitive loss should be considered as end points in AF trials going forward.
The authors report their findings online February 27, 2012 in CMAJ.
50% increase in admission to long-term-care facilities in those with AF
The post hoc analysis of ONTARGET and TRANSCEND--studies aimed at evaluating treatment with ACE inhibitors and/or ARBs in reducing CVD--involved 31 546 patients. The cognitive function of participants was measured at baseline and after two and five years using the Mini-Mental State Examination (MMSE) and other variables.
We are talking about a major loss of independence, which is clearly evident and also present in those patients who did not have any episode of stroke.
The researchers used Cox regression modeling to adjust for the main confounders and to determine the association between AF and their primary outcomes: a decrease of three or more points on the MMSE score, incident dementia, loss of independence in performing activities of daily living, and admission to long-term-care facilities.
At baseline, 3.3% of patients had AF, with the condition developing in an additional 2052 participants (6.5%) during a median follow-up of 56 months.
AF was associated with cognitive decline (hazard ratio 1.14), new dementia (HR 1.30), loss of independence in performing activities of daily living (HR 1.35), and admission to long-term-care facilities (HR 1.53).
This matters for the patient, because we are talking about a major loss of independence.
The results "were consistent among participants with and without stroke or receiving antihypertensive drugs," say Marzona et al.
Marzona says a limitation of the work is the fact that the patients in these trials were already at high risk of cardiovascular disease, so the results are not necessarily transferable to the entire population affected by AF. Hence, there is a need for future studies.
"But it's possible that AF, which is strongly associated with stroke, could also be associated with subclinical cerebrovascular disease that could lead to this functional decline in time," she maintains. "This matters for the patient, because we are talking about a major loss of independence, which is a very important issue."
Marzona has no relevant conflicts of interest. Disclosures for the coauthors are listed in the paper.
Heartwire from Medscape © 2012 Medscape, LLC
Cite this: AF Predicts Severe Cognitive Decline, Even Without Stroke - Medscape - Feb 27, 2012.