If you have ever suffered from a stroke, you are most likely on a regimen of medication aimed to reduce the chances of it happening again in the future. One of the types of medications used, known as blood-thinning drugs, has been found in a recent study not only to reduce the risk of stroke, but also the risk of dementia.
Dementia is a disabling disorder that severely affects the individual. It is a persistent decline in two or more cognitive abilities such as memory, judgment, language, and abstract thinking. Being frustrated about your forgetfulness is not dementia, as if it was, you wouldn’t even notice that you were forgetting; this is an important distinction.
Dementia patients have difficulty performing simple tasks such as paying bills and dressing. They get lost easily despite being familiar with the surrounding area and may show poor judgment or behave in socially inappropriate ways.
Blood thinners, also known as anticoagulants, are commonly used to prevent blood clots. Patients with atrial fibrillation, a condition characterized by an abnormal heart rhythm, are predisposed to the development of blood clots and are put on prophylactic blood thinners.
The researchers looked at 444,106 patients diagnosed with atrial fibrillation between 2006 and 2013. Patients on blood thinners were found to have a 29 percent lower risk of developing dementia than those not on blood thinners.
However, upon further investigation, the researchers discovered that the reduction was even greater—48 percent.
Anticoagulant treatment in atrial fibrillation patients has always been done with the sole objective of preventing abnormal blood clot formation. This protective effect against dementia was not clear until now, and possibly due to the prevention of microscopic strokes from small blood clots that eventually lead to cognitive deterioration.
About 54 percent of patients taking part in the study were not on any oral anticoagulants, such as warfarin, apixaban, dabigatran, edoxaban, or rivaroxaban. By the time the study ended, about 26,210 had been diagnosed with dementia.
The researchers concluded that for this study, lack of oral anticoagulants, aging, Parkinson’s disease, and alcohol abuse were the strongest predictors for dementia development.
Additionally, they found that the sooner oral anticoagulant treatment could be initiated for atrial fibrillation, the greater the protective effect against dementia.
“Patients start on oral anticoagulation for stroke prevention but they stop after a few years at an alarmingly high rate. In the first year, approximately 15% stop taking the drugs, then approximately 10% each year. In this study, we found that only 54% of patients were on oral anticoagulant treatment. If you know that AF eats away your brain at a slow but steady pace and that you can prevent it by staying on treatment, I think most AF patients would find this a very strong argument for continuing treatment,” said Dr Friberg an associate professor of cardiology at the Karolinska Institute
The researchers stress that the most important finding from their study was that patients who started early on blood thinning medication reaped the greatest benefit after being diagnosed with atrial fibrillation. Their continued use is what provides protection against dementia.
However, the evidence found during this study cannot prove or disprove a causal relationship between oral blood thinners and dementia, as many limitations for a discovering this definitive answer still exist.