Cirrhosis associated with increased risk of stroke, study finds
Researchers performed a retrospective cohort study using a random 5% sample of more than 1.6 million inpatient and outpatient Medicare claims from Jan. 1, 2008, through Dec. 31, 2014.
Patients with cirrhosis face an increased risk of stroke, particularly hemorrhagic stroke, a study found.
To investigate the association between cirrhosis and types of strokes, researchers performed a retrospective cohort study using a random 5% sample of more than 1.6 million inpatient and outpatient Medicare claims from Jan. 1, 2008, through Dec. 31, 2014. The primary outcome was stroke. Secondary outcomes were ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage. Results were published online June 5 by JAMA Neurology.
Among 1,618,059 beneficiaries, 15,586 patients (1.0%) had cirrhosis. The mean age was 74.1 years, and 7,263 (46.6%) were women. During a mean of 4.3 years of follow-up, 77,268 patients were hospitalized with a stroke. The incidence of stroke was 2.17% (95% CI, 1.99% to 2.36%) per year in patients with cirrhosis and 1.11% (95% CI, 1.10% to 1.11%) per year in patients without cirrhosis.
After adjustment for demographic characteristics and stroke risk factors, patients with cirrhosis had a higher risk of stroke (hazard ratio [HR], 1.4; 95% CI, 1.3 to 1.5). The magnitude of association appeared to be higher for intracerebral hemorrhage (HR, 1.9; 95% CI, 1.5 to 2.4) and subarachnoid hemorrhage (HR, 2.4; 95% CI, 1.7 to 3.5) than for ischemic stroke (HR, 1.3; 95% CI, 1.2 to 1.5).
Multiple factors may influence this effect, the authors wrote, including the following:
- Patients with cirrhosis have an unstable imbalance of prothrombotic and prohemorrhagic derangements.
- Risk of stroke conferred by the patients' underlying vascular risk factors may be amplified by cirrhosis, perhaps because of mixed coagulopathy.
- Underlying causes of cirrhosis may contribute to stroke risk.
- “[O]ur findings challenge the weakly supported notion that cirrhosis is protective against ischemic stroke and complement increasing evidence of an increased risk of hemorrhagic stroke in patients with cirrhosis, particularly in the context of advanced age and multiple vascular risk factors,” the authors wrote.