Young adults with iron deficiency anemia are more likely to experience an ischemic stroke, according to an analysis of health records from over 21 million individuals in the United States.
Patients aged 15 to 49 years who had an ischemic stroke were five times more likely to have had iron deficiency anemia (IDA) in the year prior compared to those who did not experience a stroke. After adjusting for other risk factors including hypertension, smoking, and diabetes, IDA remained associated with a 39% increased likelihood of stroke.
Among the 36,989 patients with a first-time ischemic stroke, 1,880 (5.1%) had a prior diagnosis of IDA; in contrast, only 1.1% of the 21.7 million individuals without stroke had an IDA.
IDA, which impairs red blood cell production and oxygen delivery, is one of the most common nutritional deficiencies, particularly in young women and underserved populations. While IDA is a known stroke risk factor in children, its association with stroke in young adults had not been thoroughly studied on a large scale.
Researchers used a nationwide U.S. electronic health record database covering more than 300 hospitals, focusing on patients diagnosed with stroke from 1999 to 2018. The analysis included only those younger than 50 and excluded individuals with conditions that might confound the results, such as cancer, pregnancy, or inherited blood disorders.
Even after adjusting for multiple factors, IDA remained an independent predictor of stroke. Other significant risk factors included hypertension (odds increased more than threefold), dyslipidemia, diabetes, and smoking.
The analysis also revealed differences based on age and race. African American adults aged 20 to 39 with IDA had a higher risk of stroke than older Caucasian adults with the same condition. "It is plausible that the younger cohort had fewer regular health care visits for medical risk factor management, and lack of access to a nutritious diet which could lead to increased atherosclerotic risk factors and IDA," wrote corresponding author Jahnavi Gollamudi, MD, of the University of Cincannti, and colleagues.
Though the exact mechanisms are still being studied, the researchers suggested that IDA may create a hypercoagulable state where blood is more prone to clotting. Possible biological pathways include reduced red blood cell flexibility, elevated clotting proteins, and increased inflammation.
The study authors reported several limitations—with a retrospective analysis, they could not directly measure iron levels or include patients with iron deficiency who had not yet developed anemia. The findings may also underestimate the true prevalence of IDA due to underdiagnosis in real-world settings.
Nonetheless, the results suggest IDA may be an underrecognized risk factor for stroke in younger adults, noted the researchers. They emphasized the need for improved screening and treatment strategies for IDA in this population.
The authors reported no conflicts of interest.
Source: eJHaem
