Left-sided strokes are more often recognized than right-sided strokes: the Rotterdam study

Area of Science:

• Neurology
• Neuroimaging
• Epidemiology

Background:

• Left-sided strokes are anecdotally reported as more common than right-sided strokes.
• It remains unclear if this reflects true incidence or diagnostic bias.

Purpose of the Study:

• To investigate the frequency of clinically diagnosed left- and right-sided strokes and transient ischemic attacks (TIAs).
• To compare these clinical frequencies with the distribution of left- and right-sided infarcts detected by MRI in a population-based cohort.

Main Methods:

• The study utilized data from the population-based Rotterdam Study (1990-2012).
• 13,894 participants were followed for incident stroke and TIA.
• MRI scans from 5081 participants were analyzed for supratentorial cortical and lacunar infarcts.
• Frequencies were compared using binomial and Fisher exact tests.

Main Results:

• Ischemic strokes (57.7%) and TIAs (57.8%) were more frequently diagnosed as left-sided compared to right-sided.
• In contrast, MRI analysis revealed no significant left-right difference in the distribution of infarcts (51.9% left-sided).

Conclusions:

• Clinical diagnosis of ischemic stroke and TIA shows a left-sided predominance.
• This observed laterality bias in clinical recognition is not supported by neuroimaging findings.
• Increased clinical awareness and attention towards symptoms of right-sided strokes and TIAs are recommended.