In a new study to be presented at this year’s European Congress on Obesity (ECO2026) in Istanbul, Turkey (12-15 May), researchers show that low birth weight infants have an increased risk of stroke in young adulthood, independent of body mass index (BMI) as young adults and gestational age at birth. A study of about 800,000 people in Sweden suggests that low birth weight may be included in stroke risk assessment in adults, say the authors, including Dr. Lina Lilja and Dr. Maria Vigdel from the University of Gothenburg in Sweden.
Although overall stroke incidence has declined over the past few decades in high-income countries, this decline has been less pronounced in young and middle-aged people than in older people. Stroke rates are increasing further in some regions and younger age groups, including low-income countries in Southeast Asia and Oceania, and high-income countries such as Sweden, the United States, and the United Kingdom (see examples in Notes to Editors).
The authors therefore decided to investigate whether several factors, including birth weight, gestational age at birth, and BMI in young adulthood, could be risk factors for stroke in young adults. Of course, for today’s young people, these life events have already passed, but for children who have not yet conceived, these are factors that can be targeted for intervention. The authors investigated both ischemic stroke, which is caused by blockage of blood vessels in the brain (accounting for more than three-quarters of strokes, depending on location), and a more common form of stroke. and intercerebral hemorrhage (ICH) or “brain hemorrhage” strokes (representing up to a quarter of all strokes).
This population-based study included 420,173 men and 348,758 women (i.e., currently alive and aged 43 to 53 years, representing all births recorded in that year) born in Sweden between 1973 and 1982, with data on birth weight, gestational age, and BMI in young adulthood from the Medical Birth Register and the National Conscription Register, respectively. Study participants were followed until December 31, 2022.
Information on early stroke events in adults was obtained from the Swedish national patient register and cause of death register. 2,252 first stroke events, mean age 36 years. The number of ischemic stroke (IS) events was 1,624, with a mean age of 37 years. There were 588 intracerebral hemorrhage and stroke (ICH) events, with a mean age of 33 years (40 of the first stroke events were unclassified). Enrollment of diagnoses in these registries is mandatory, providing comprehensive national data on people admitted to hospital or dying from stroke. The relatively low number of events reflects that these people are young adults with a low absolute risk of stroke. All analyzes were adjusted for sex, year of birth, gestational age, country of birth of parents, and age of adult BMI.
The authors found that people (men and women combined) whose birth weight was less than the median birth weight (3.5 kg) had a 21% increased risk of ischemic stroke as well as all stroke events combined, and a 27% increased risk of intracerebral hemorrhage stroke alone, compared with those whose birth weight was above the median. Women with a birth weight below the median (3.5 kg) had a combined 18% increased risk of all strokes compared with individuals with a birth weight above the median, and men had a 23% increased risk.
The results were independent of gestational age (how long the child was in the womb before birth) or BMI as a young adult. Gestational age itself was not associated with stroke risk. The overall outcome of each case was similar for women and men.
The authors conclude: ”We demonstrated that reduced birth weight is associated with increased risk of stroke in early adulthood. There was a similar increased risk for both men and women and for both major types of ischemic and hemorrhagic stroke, and the results were independent of gestational age at birth or BMI in young adults. These findings suggest that low birth weight may be included in the assessment of stroke risk in adults. ”
sauce:
European Obesity Research Association
