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Published on: December 23, 2022
Trigger factors in patients with a patent foramen ovale-associated stroke: A case-crossover study
Maikel Hm Immens1, Merel S Ekker1, Esmee Verburgt1
1Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.
Insights
Fever, flu-like illness, and intense exercise can transform an asymptomatic patent foramen ovale (PFO) into a stroke-causing condition in young adults. This study identified key triggers for PFO-associated strokes.
Area of Science:
- Cardiology
- Neurology
- Genetics
Background:
- Patent foramen ovale (PFO) is a congenital heart defect present from birth.
- PFO is linked to strokes in young adults, but triggers converting it to a stroke cause are unknown.
- Investigating triggers for PFO-associated strokes is crucial for understanding stroke mechanisms in young individuals.
Purpose of the Study:
- To identify potential trigger factors associated with ischemic stroke in young adults with PFO.
- To quantify the risk associated with specific triggers in PFO-positive stroke patients.
- To elucidate the transition from an asymptomatic PFO to a stroke-causing PFO.
Main Methods:
- The ODYSSEY study enrolled patients aged 18-49 with first-ever ischemic events.
- A multicenter prospective cohort study utilized questionnaires to assess trigger factor exposure.
- A case-crossover design analyzed relative risks (RR) of triggers for PFO-associated stroke.
Main Results:
- 124 patients with PFO-associated stroke were analyzed from 1043 participants.
- Fever showed a high RR of 26.0 for PFO-associated stroke.
- Flu-like illness (RR 24.2) and vigorous exercise (RR 3.31) were also significantly associated with PFO-related strokes.
Conclusions:
- Flu-like illness, fever, and vigorous exercise are identified as potential triggers converting asymptomatic PFO to stroke-causing PFO in young adults.
- These findings highlight specific factors that may precipitate stroke events in individuals with PFO.
- Understanding these triggers can inform preventative strategies for young stroke survivors with PFO.
Background:
Patent foramen ovale (PFO) is a congenital anatomical variant which is associated with strokes in young adults. Contrary to vascular risk factors and atherosclerosis, a PFO is present from birth. However, it is completely unknown how an anatomical structure that is already present at birth in a large proportion of the population can convert into a PFO that causes stroke in a few. Recent studies reported a significant association between certain trigger factors and ischemic stroke in young adults. This study aims to investigate these triggers in PFO-associated stroke.
Methods:
The ODYSSEY study, a multicenter prospective cohort study between 2013 and 2021, included patients aged 18-49 years experiencing their first-ever ischemic event. Participants completed a questionnaire about exposure to potential trigger factors. A case-crossover design was used to assess the relative risks (RR) with 95% confidence intervals (95% CI). The primary outcome was the RR of potential trigger factors for PFO-associated stroke.
Results:
Overall, 1043 patients completed the questionnaire and had an ischemic stroke, of which 124 patients had a PFO-associated stroke (median age 42.1 years, 45.2% men). For patients with PFO-associated stroke, the RR was 26.0 (95% CI 8.0-128.2) for fever, 24.2 (95% CI 8.5-68.7) for flu-like disease, and 3.31 (95% CI 2.2-5.1) for vigorous exercise.
Conclusion:
In conclusion, flu-like disease, fever, and vigorous exercise may convert an asymptomatic PFO into a stroke-causing PFO in young adults.
Data Access Statement:
The raw and anonymized data used in this study can be made available to other researchers on request. Written proposals can be addressed to the corresponding author and will be assessed by the ODYSSEY investigators for appropriateness of use, and a data sharing agreement in accordance with Dutch regulations will be put in place before data are shared.
