After a stroke, patients have increased risk of recurrent stroke, dementia

Patients who had a stroke had a three-fold increased risk of recurrent stroke and a nearly two-fold increased risk of dementia within one year of their stroke compared with patients who never had a stroke, according to a population-based study.

Patients were at an increased risk of recurrent stroke and dementia for at least five years following their first stroke.

Lead researcher Marileen L.P. Portegies, MD, of Erasmus University Medical Center in Rotterdam, Netherlands, and colleagues published their results online in Stroke on July 14.

The researchers analyzed 1,243 participants in the Rotterdam Study who had a stroke between 1990 and 2012. They then matched them based on age, sex, examination round and stroke date with 4,928 participants who did not have a stroke.

At baseline, the mean age was approximately 80 years old, while 60.4 percent of patients were females. Patients who had a stroke were more likely to have high cholesterol and hypertension compared with those who did not have a stroke.

During a median follow-up period of 1.68 years, 233 of the patients had a recurrent stroke. During a median follow-up period of 5.22 years, 520 of the patients had their first stroke.

In addition, 146 stroke patients developed dementia during a median follow-up period of 2.41 years, while 653 patients without stroke developed dementia during a follow-up period of 5.43 years.

The researchers said that the main factors contributing to a recurrent stroke were hypertension, low high-density lipoprotein cholesterol, diabetes, smoking and transient ischemic attack.

They also mentioned that the total population attributable risk for all risk factors combined was similar in people with stroke and those without stroke. In addition, they found no significant associations of prestrike cardiovascular risk factors with dementia.

They added that prestrike cardiovascular risk factors accounted for 39 percent of recurrent strokes and 10 percent of poststroke dementia.

“Taken together, this emphasizes the need of optimizing both primary and secondary preventions,” the researchers wrote. “At the same time, our results encourage exploration of other potentially modifiable factors.”

The researchers also mentioned a few limitations of the study, including that they only measured prestroke risk factors once and did not have data on stroke severity.