About one in seven strokes occur in people aged 15 to 49, and the number is rising. The causes in younger adults often look different from those in older people. While high blood pressure and diabetes still play a role, strokes in young adults are more likely to stem from structural heart defects, torn arteries, blood clotting disorders, and congenital blood vessel abnormalities that may have gone undetected for years.
Traditional Risk Factors Are Showing Up Earlier
The CDC attributes the rise in young adult strokes to increasing rates of obesity, high blood pressure, and type 2 diabetes in younger populations. These conditions damage blood vessels over time, and when they develop in someone’s twenties or thirties rather than their fifties, the vascular damage starts accumulating decades earlier. High blood pressure in particular remains the single most important modifiable stroke risk factor at any age.
What makes this trend alarming is that many young people don’t know they have these conditions. A 25-year-old with undiagnosed high blood pressure may go years without a routine checkup. By the time a stroke occurs, the underlying damage is well established.
Arterial Tears in the Neck
Cervical artery dissection, a tear in the lining of blood vessels running through the neck to the brain, is one of the most common causes of stroke in young and middle-aged adults. When the inner wall of a carotid or vertebral artery tears, blood can pool and clot at the injury site. If that clot breaks loose, it travels to the brain and blocks blood flow, causing an ischemic stroke.
These tears can happen after seemingly minor events: a car accident, a chiropractic neck adjustment, a forceful cough, or even a roller coaster ride. Sometimes no clear trigger is identified. People with connective tissue disorders are at higher risk because their blood vessel walls are structurally weaker to begin with.
A Hole in the Heart Most People Don’t Know About
Everyone is born with a small opening between the upper chambers of the heart called a foramen ovale. It normally closes shortly after birth, but in roughly 25% of people, it never fully seals. This leftover opening, called a patent foramen ovale (PFO), usually causes no problems. But it can allow a blood clot from the veins to pass through the heart and travel directly to the brain, bypassing the lungs where clots are normally filtered out.
This mechanism, called paradoxical embolism, is a major factor in unexplained strokes among young adults. Research published in the Journal of the American Heart Association found that about 60% of cryptogenic ischemic strokes (strokes with no obvious cause) in young adults can be attributed to a PFO. In one study, over half of young patients with unexplained strokes had a PFO detected on imaging. Many of these people had no idea the opening existed until after their stroke.
Blood Clotting Disorders
Some people’s blood is naturally more prone to clotting than it should be, a category of conditions called thrombophilia. These disorders increase the production of clot-forming proteins or reduce the body’s ability to break clots down. In young stroke patients, inherited clotting abnormalities include deficiencies in natural anticoagulant proteins, genetic mutations that make clotting factors overactive, and elevated levels of an amino acid called homocysteine that damages blood vessel walls.
Antiphospholipid syndrome deserves special mention. It’s an autoimmune condition where the body produces antibodies that make blood clot too easily. It can cause strokes in people who are otherwise young and healthy, and it’s one of the more treatable clotting disorders once identified. The tricky part is that these conditions rarely produce symptoms before the stroke itself, so they’re typically discovered only during the diagnostic workup afterward.
Clotting disorders and PFOs often work together. A person with a blood clotting tendency who also has a PFO faces a compounded risk: their blood forms clots more readily, and those clots have a direct path to the brain through the heart opening.
Blood Vessel Abnormalities in the Brain
The split between ischemic strokes (caused by blocked blood flow) and hemorrhagic strokes (caused by bleeding) is roughly even in young adults, close to 50/50 in study populations. That’s a stark contrast to older adults, where ischemic strokes dominate. One reason hemorrhagic strokes are proportionally more common in younger people is arteriovenous malformations, or AVMs.
An AVM is a tangle of abnormal blood vessels where arteries connect directly to veins without the usual network of tiny capillaries in between. This puts extreme pressure on vessel walls that aren’t built to handle it, making them thin and fragile. The risk of a brain AVM bleeding is around 2% to 3% per year, and in about half of all cases, the first sign of the AVM is a hemorrhage. Brain AVMs account for roughly 2% of all hemorrhagic strokes overall, but in children and young adults who experience brain bleeding, they are frequently the cause.
Aneurysms can also form at the site of an AVM, creating additional weak spots that may rupture. Many people live with AVMs for decades without symptoms, then experience a sudden, severe bleed with no warning.
Genetic Conditions That Damage Blood Vessels
A small but important subset of young adult strokes are caused by inherited diseases that weaken blood vessels from within. CADASIL is the most well-known of these. It’s caused by a mutation in a single gene (NOTCH3) that controls the health of smooth muscle cells lining small blood vessels in the brain. Over time, these cells deteriorate and die, reducing blood flow and causing small areas of tissue death throughout the brain.
People with CADASIL often experience migraines with visual auras years before their first stroke, which can occur anytime from childhood to late adulthood but typically happens in mid-adulthood. Because the condition doesn’t involve the usual stroke risk factors like high cholesterol or high blood pressure, it can be missed entirely unless a doctor specifically considers genetic causes. Only one copy of the mutated gene is needed to cause the disease, meaning a parent with CADASIL has a 50% chance of passing it to each child.
Pregnancy and the Postpartum Period
High blood pressure during pregnancy is the leading cause of stroke in pregnant women and women who have recently given birth. It affects up to 12% of pregnancies in the United States. Preeclampsia, a more severe form, can cause dangerous spikes in blood pressure along with headaches, vision changes, and swelling in the hands and face. At its most severe, preeclampsia triggers seizures (a condition called eclampsia) and can lead directly to stroke.
The risk doesn’t end at delivery. The postpartum period, especially the first few weeks, carries elevated stroke risk as the body’s clotting system remains in a heightened state designed to prevent bleeding during childbirth. This pro-clotting shift, combined with the physical stress of delivery and possible lingering blood pressure problems, creates a window of vulnerability.
Drug Use and Acute Triggers
Stimulant drugs like cocaine and methamphetamine cause sudden, dramatic spikes in blood pressure that can rupture blood vessels in the brain. Cocaine in particular has a well-documented association with both ischemic and hemorrhagic strokes. The sympathomimetic effects, meaning the drug mimics the body’s “fight or flight” response, constrict blood vessels and raise blood pressure to dangerous levels within minutes of use. For someone who already has a small, undetected aneurysm or AVM, that pressure surge can be the event that triggers a bleed.
Heavy alcohol use also contributes, though the relationship is more complex. Chronic heavy drinking raises blood pressure over time and can impair the blood’s ability to clot properly, increasing the risk of hemorrhagic stroke.
Why Strokes in Young Adults Get Missed
One of the most dangerous aspects of stroke in young people is that doctors often don’t suspect it. In one study, 33% of stroke patients under age 35 were initially misdiagnosed, compared to 9% of those 35 and older. Young patients arriving at the emergency room with stroke symptoms were told they had vertigo, migraines, alcohol intoxication, inner ear infections, or seizures.
Strokes affecting the back of the brain were especially likely to be missed, with 35% misdiagnosed compared to just 5% of strokes in the front of the brain. That’s because posterior strokes tend to cause dizziness, coordination problems, and vision changes rather than the classic one-sided weakness and slurred speech that most people associate with stroke. In a young person, those symptoms look even less like a stroke to the untrained eye.
Recovery Looks Different at a Younger Age
Young stroke survivors generally have better survival rates and lower immediate disability than older patients, but “better” is relative. While a young person’s brain may have more capacity to rewire itself after injury, the long-term consequences are profound in ways that don’t apply to retirees. A stroke at 35 can mean decades of living with fatigue, cognitive difficulties, depression, or physical limitations during what should be peak working and parenting years.
Interestingly, when it comes to formal rehabilitation, research shows that age itself doesn’t predict recovery as much as you’d expect. A large study of over 2,200 stroke patients found that middle-aged, old, and very old patients all improved by essentially the same amount during four weeks of intensive inpatient rehabilitation. What mattered more than age was the intensity of therapy received. The advantage young survivors do hold is time: more years ahead to continue improving, adapt, and rebuild their lives around whatever deficits remain.