Sharp Rise in Stroke Among Young
has shown a sharp increase in the incidence of stroke in young adults, with a second study identifying a similar trend in high income countries generally.
Sharp Rise in Stroke Among Young
Dr Rob Hicks, MB BS | 02 November 2022
A study of people in Oxfordshire has shown a sharp increase in the incidence of stroke in young adults, with a second study identifying a similar trend in high income countries generally.
The authors of the two recent studies said that the "traditional view" is that vascular risk factors, such as high blood pressure, diabetes, and obesity, play a "minor role" in young stroke. However, recent studies have begun to contradict this view, they said, and highlighted that young stroke is a growing problem in high-income countries.
In the studies, published in JAMA, the researchers set out to answer two questions. The first was: 'Did stroke incidence rates diverge in younger versus older people from 2002 to 2018?'
To try to answer this question, researchers from theNuffield Department of Clinical Neuroscience at the University of Oxfordperformed a prospective population-based incidence study, conducted from April 2002 to March 2018. Drawing on data from The Oxford Vascular Study, included were 94 567 people registered with GP practices across Oxfordshire. The main outcome measures were changes in incidence of stroke, transient ischaemic attack (TIA), and other major vascular events - myocardial infarction, sudden cardiac death, and peripheral vascular events - stratified by age, sex, diagnostic workup, aetiology, and severity.
The researchers also took into account other factors, such as lifestyle, changes in diagnostic practices, control of traditional vascular risk factors, and sex-specific causes of stroke.
Increase in Young, Decrease in Older
There were 2429 incident strokes during the study period - mean age 73.6 years, 51.3% female. The researchers found that between 2002-2010 and 2010-2018 there was a 67 per cent increase in stroke incidence among adults under 55 years, and a 15 per cent decrease among adults 55 years or older. The significant increase in incidence at younger than 55 years was independent of sex, stroke severity, pathological subtype, and changes in investigation, and was also seen for TIA (incidence rate ratio [IRR] 1.87; 95% CI, 1.36 to 2.57), but not for myocardial infarction and other major vascular events (IRR, 0.73; 95% CI, 0.58-0.93), reported the authors.
Although TIA and stroke at younger than 55 years were significantly associated with diabetes (risk ratio [RR], 3.47; 95% CI, 2.54 to 4.74), hypertension (RR, 2.52; 95% CI, 2.04 to 3.12), current smoking (RR, 2.38; 95% CI, 1.92 to 2.94), and obesity (RR, 1.36; 95% CI, 1.07 to 1.72), the authors pointed out that the "significant increase" in incidence from 2002-2010 to 2010-2018 was still seen in individuals without these risk factors.
A similar divergence in incidence was not found for other vascular events, such as heart attacks, they pointed out. "Given the absence of this divergence for other vascular events, further research is needed to understand the causes of this difference," urged the authors.
The increase was greatest in professional/managerial occupations (IRR, 2.52; 95% CI, 1.75 to 3.62) and least in partially skilled/unskilled occupations (IRR, 1.17; 95% CI, 0.79 to1.74). The researchers suggested this could be explained by a role for work-related stress, low physical activity, and long working hours - each of which were more strongly associated with risk of stroke than heart attack.
Dr Angela Hind, chief executive of the Medical Research Foundation, said: "Historically, we've thought of stroke as only affecting older adults, but studies like this suggest a growing problem in young adults."
The prevalence of traditional vascular risk factors in young people with stroke was also high, the authors said, emphasising the "importance of identifying and managing these risk factors".
Rise in Young Stroke in High-Income Countries
The second question the researchers wanted to answer was: What is happening to stroke incidence in younger versus older adults in high-income countries in the 21st century?'
They pointed out that overall stroke incidence was falling in high-income countries, but that data on time trends in incidence of stroke in individuals younger than 55 years was "conflicting".
For the second study - a systematic review and meta-analysis - the researchers searched PubMed and EMBASE from inception to February 2022, with data from the Oxford Vascular Study also included.
Among 50 studies, they found that temporal trends in stroke incidence were diverging by age in high-income countries, with less favourable trends at younger versus older ages. They commented that a "fall in incidence" at older ages was not being seen at younger ages. This, they said, emphasised the "urgent need" to better understand aetiology and prevention of stroke at younger ages.
Dr Linxin Li, Medical Research Foundation fellow, University of Oxford, said: "Our study shows a worrying rise in young stroke cases across Oxfordshire, reflecting a similar picture across other high-income countries."
Dr Hind explained that stroke in young adults can have a "huge impact", and that economic, social and personal consequences can be "devastating".
"More research needs to be done to increase understanding of the causes of young stroke and the best ways of preventing it," she said.
"Establishing the importance of known risk factors in young stroke will help to raise general awareness of the need for better control," emphasised Dr Li. "We also need better ways of identifying young people at high risk of stroke, as current risk models are based on predictors of stroke in older people," she said.
Medscape UK
Me: So what has changed “recently” = Covid virus and mRNA vaccines