MRI serves as ‘useful addition’ in clinical evaluation of suspected stroke
The initial diagnosis of non-ischemic events, or “stroke mimics,” occurred more frequently in women than men in a secondary analysis of DOUBT study data, though diagnostic revisions were often made for both men and women.
The findings, which were published in Neurology, also indicated that early brain MRI “is a useful addition” to the clinical evaluation of transient or minor neurological events.
“Brain MRI is frequently done in patients who are suspected to have strokes, but this study focused on patients who have mild symptoms like numbness or dizziness,” Amy Y. X. Yu, MDCM, MSc, FRCPC, a clinician-scientist and staff stroke neurologist at Sunnybrook Health Sciences Center in Toronto and an assistant professor of medicine at the University of Toronto, told Healio Neurology. “These symptoms are often felt to be atypical for stroke. Therefore, there is a high degree of uncertainty about whether or not these events could be related to a stroke.”
Yu and colleagues analyzed data from the Diagnosis of Uncertain-Origin Benign Transient Neurological Symptoms (DOUBT) study and used multivariable logistic regression analysis to determine the link between patient sex and outcomes.
“Differences in diagnostic revisions by sex are not well understood but are important because the initial diagnosis frequently guides the timing and extent of investigations, which can ultimately influence the final diagnosis,” the researchers wrote.
The researchers conducted a post hoc analysis of the DOUBT study, an international, multicenter prospective cohort study that enrolled patients with a probable minor stroke or transient ischemic attack (TIA) within the previous 8 days. Yu and colleagues included 1,028 patients’ data in the analysis (women: 51%; median age: 63 years). Diagnostic revision from stroke mimic to cerebral ischemia served as the primary outcome.
Yu and colleagues found that women were more likely to be initially diagnosed with stroke mimic (54% vs. 42%; OR = 1.60; 95% CI, 1.24-2.07) compared with men.
“Given MRI is more likely to be done when a stroke is suspected, women may be more vulnerable to not having this test,” Yu said.
The study findings demonstrated that, among 496 patients initially diagnosed with stroke mimic, women were less likely than men to have a stroke mimic diagnosis changed to cerebral ischemia after brain MRI and other investigations (13% vs. 20%; OR = .53 [95% CI, 0.32-0.88]), but women initially diagnosed with stroke mimic had similar odds for having an MRI that showed acute ischemia (5% vs. 8%; OR = 0.56; 95% CI, 0.26-1.21).
“This difference is not statistically significant, suggesting that MRI is helpful in both men and women to accurately diagnose stroke,” Yu said.
Of 532 patients who received an initial cerebral ischemia diagnosis, women were more likely than men to receive a revised diagnosis of stroke mimic (49% vs. 38%; OR = 1.70; 95% CI, 1.18-2.45). Overall, women were less likely to have an MRI that showed a diffusion-weighted image hyperintense lesion (10% vs. 17%; OR = 0.52; 95% CI, 0.36-0.76) compared with men and were also less likely to receive a final diagnosis of cerebral ischemia (30% vs. 45%; OR = 0.52; 95% CI, 0.40-0.68).
“[S]troke can affect people in different ways, beyond the typical symptoms of weakness or speech difficulty,” Yu said. “If a stroke is suspected, further imaging of the brain is needed.”