Stroke risk may increase after traumatic brain injury

Risk for stroke may increase after a traumatic brain injury (TBI), according to a new study.

Researchers in Taiwan used a national database to compare stroke risk in patients who had sustained a TBI and those who had not. The population-based study included 23,199 patients with a diagnosis of TBI who had received ambulatory or inpatient care and 69,597 control patients without TBI matched for sex, age, and year of index health care use. Patients were followed for five years, and both short-term and long-term effects were assessed. The study results were published online July 28 by Stroke.

The mean age of patients in both groups was 41.6 years, and more than half (53.6%) were men. At three months, 2.91% of patients in the TBI group and 0.30% in the non-TBI group had had strokes. At one year and five years, these percentages were 4.17% versus 0.96% and 8.20% versus 3.89%, respectively. After adjustment for comorbid conditions and sociodemographic characteristics, patients with TBI had a 10.21 (95% CI, 8.71 to 11.96) times greater risk for stroke at three months, a 4.61 (95% CI, 4.16 to 5.11) times greater risk at one year and a 2.32 (95% CI, 2.17 to 2.47) times greater risk at five years. Patients with TBI also had a greater risk for all subtypes of stroke, especially intracerebral hemorrhage, over the five-year follow-up period.

The authors acknowledged that the database used for the study included only patients who sought treatment for TBI and stroke, that some patients could have been lost to follow-up, and that data on clinical severity, imaging and such variables as smoking and body mass index were not available. However, they concluded that their study shows an elevated risk for stroke after TBI. “A coordinated and systematic approach should be adopted to prevent patients with TBI from subsequent stroke and to optimize outcomes,” they wrote. “Future studies are needed to elucidate the mechanisms by which TBI is associated with stroke.”