Stroke in young people is defined as a stroke that occurs in young people under the age of 35. The results of a domestic epidemiological survey show that young people account for 9.77% of all strokes, mainly ischemic strokes, with a male predominance. The incidence of ischemic stroke in young people has been increasing recently, and early detection of the cause of stroke in young people is very important for prevention and treatment. In this paper, the common causes and risk factors for stroke in young people are reviewed as follows.
I. Atherosclerosis
Most scholars believe that atherosclerosis is the main cause of stroke in young people. The literature reports that in young stroke patients, atherosclerosis is considered to be the cause if no clinically significant cause is found, but cerebral arteriography shows different types and degrees of plaque in the proximal arteries. This is related to the increasing number of young people with dyslipidemia, hypertension, diabetes mellitus, obesity, smoking, stressful work and high calorie intake. KitterSJ et al. 1 studied the etiology of 428 first-episode young stroke patients and found that atherosclerosis accounted for 3.8% of large arteries, often carotid or basilar artery stenosis, thus pointing to atherosclerosis as the most important cause of intracranial artery stenosis.
Second, non-atherosclerotic vascular lesions
1.Sealed aneurysm
It is formed when the blood in the head and neck vessels penetrates into the subintima of the vessels and then hematoma is formed along the long axis of the vessels and extends longitudinally between the vessel walls for a certain distance. It is often accompanied by a longitudinal extension of the vessel wall for a distance and is often accompanied by tearing of the intima. The literature reports , that this disease accounts for 26% of stroke patients under 35 years of age. The most common cause of cervical vascular entrapment aneurysms is trauma. In addition, connective tissue disease, type IV, is also prone to entrapment aneurysms.
2. Moyamoya disease is also known as smoker’s disease and anomalous vascular network disease at the base of the brain. The etiology of this disease is unclear, and both congenital and acquired evidence have been found. The disease occurs in Asia, mostly in Japan, and often involves children, young adults, and women. The clinical manifestations of the disease are highly variable, with patients under 20 years of age showing mostly ischemic manifestations, with episodes of limb weakness or hemiparesis, which may alternate between right and left, with recurrent episodes, or may develop from one side to bilateral paralysis. patients over 20 years of age are more likely to have subarachnoid hemorrhage, which is caused by increased proximal pressure after vascular occlusion, which can easily rupture the fragile and thin-walled collateral circulation network or small penetrating vessels. Cerebral arteriography is the most reliable diagnostic method, and the combined use of MRI and MRA can better identify the concomitant vascular network as well as small infarct foci within the deep penetrating branch blood supply.
3. Takayasus arteritis is also known as primary or nonspecific aortitis, aortic arch syndrome, and pulselessness. It is common in Orientals and young women, with a high incidence in the national population. It is a chronic progressive inflammatory disease of the aorta and its trunk branches due to an autoimmune reaction. Stenosis or occlusion of the affected arteries can cause damage to the heart, lungs, brain, spinal cord, kidneys, digestive system, and surrounding tissues and organs. Clinically, ischemic cerebrovascular disease can manifest as TIA, cerebral infarction, lacunar cerebral infarction, watershed infarction, and Moyamova’s sign. Some scholars found that cerebral arteritis narrowed or occluded blood vessels leading to cerebral infarction and caused stroke in young people through clinical analysis of 38 cases of young cerebral infarction patients, indicating that cerebral arteritis may be a causative factor of stroke in young people.
4, fibromuscular development abnormalities The pathological features of this disease are abnormal development of blood vessels, a congenital mesodermal disease, mostly seen in female patients with vascular smooth muscle and fibroblast degeneration, arteries are segmental stenosis and dilatation, the stenotic part of the artery intima and subepithelial fibers proliferation, the dilated part is muscle thinning or disappearance, weak fiber dissection, easy to complicate aneurysm. Their cerebral arteriograms have a characteristic presentation.
typical bead-like changes in the arteries.
Stenosis with or without constriction, with aneurysmal dilatation in the stenotic segments.
The arterial wall may be diverticulosis-like, smooth or pouch-like with folds when the damage is non-circular. Cerebral arteriography should be routinely performed in all young and middle-aged stroke patients with hypertension. In particular, the diagnosis of this disease should be considered in some young women with unexplained headache, tinnitus, vertigo, arrhythmia and syncope.
Nagaraja et al. study confirmed that respiratory tract infections in young stroke patients are commonly associated with B-hemolytic streptococci in the pharynx.
III. Cardiac disease
Cardiogenic stroke is more common in young people with stroke. The literature reports. Cardiogenic stroke accounts for 11.5% to 25.8% of strokes in young people from all causes. In the past, rheumatic heart disease was the most common cause of stroke. In the last decade or so, with advances in prevention and treatment, the incidence of rheumatic diseases has decreased, and valvular disease, patent foramen ovale, and arrhythmias are the most common causes of cardiac stroke. Bacterial endocarditis and arrhythmias can cause stroke. Foramen ovale insufficiency accounts for about 35% to 45% of cardiogenic strokes in young people.
IV. Abnormal blood component diseases
1. Antiphospholipid antibody syndrome is a group of clinical syndromes characterized by recurrent habitual abortion, thrombocytopenia, reticulocytosis, recurrent venous thrombosis and positive antiphospholipid antibody (APL). A growing number of studies have shown that APL is an important risk factor for stroke in young people. Patients with APL-positive ischemic stroke are generally characterized by a young age at first onset, few comorbid other risk factors, easy recurrence, and multifocal nature. Some scholars have found that 4.7% of young stroke patients have increased APL in their blood.
2, platelet abnormalities platelet abnormalities can cause bleeding due to abnormal platelet quality and quantity and increased capillary fragility, as well as microthrombosis due to abnormal platelet aggregation and release of reactive substances, which can develop into thrombosis.
3, Sickle cell anemia Sickle cell anemia patients contain abnormal hemoglobin S in their red blood cells, with stiff cells and poor denaturation ability, which can block microcirculation causing infarction.
4, Protein C and protein S deficiency Protein C system is an important natural anticoagulation system in the body to balance the coagulation process and prevent thrombosis, and its deficiency can easily cause the hypercoagulable state of blood, thus inducing the occurrence of ischemic stroke.
5, migraine causes vasospasm, platelet hyperfunction and increased blood viscosity, increasing the risk of stroke, of which infarction of the posterior cerebral artery is the most common.
6, homocysteine: Patients with cerebrovascular disease, especially young stroke patients, are often accompanied by increased plasma HCY concentration. An epidemiological study involving 1200 cases and corresponding controls showed that mild to moderate HCYemia significantly increased the risk of cerebrovascular disease and was positively correlated with the severity of stroke.
7.Other
Oral contraceptives
Estrogen in oral contraceptives can affect the metabolism of sugar and fat and increase blood lipids, which can lead to an increase in blood clotting factors and blood viscosity, resulting in a hypercoagulable state of blood and causing stroke.
The mechanism of pregnancy is vasospasm and the presence of hypercoagulable blood, which leads to ischemic stroke, accounting for 5% of all strokes in young people. The risk of stroke in pregnant and perinatal women has been reported to be 13 times higher than in the same age group.
Smoking and alcohol consumption
Smoking and passive smoking are the risk factors for stroke that can be intervened. The incidence of cerebral infarction in young people has been analyzed in relation to risk factors and the highest incidence of risk factors was found to be smoking. Alcohol abuse is another risk factor for stroke in young people. In a study of first-ever ischemic stroke patients aged 16 to 40 years, it was reported that alcoholism and occasional alcohol abuse were equally likely to cause ischemic stroke, and that ingestion of more than 40 g of ethanol within 24 h before the onset of stroke was a trigger for stroke.
Genetic factors
Advances in molecular genetics, particularly in the study of hereditary cerebrovascular disease associated with stroke in young people, have provided a new basis for the diagnosis and prevention of stroke in young people. Studies have shown that the influence of genetic factors is more important in young stroke patients. Traditional risk factors for ischemic stroke such as hyperlipidemia, obesity, hypertension, and diabetes mellitus also play an important role in the development of ischemic stroke in young people, and their prevention and control measures are gradually gaining attention. In conclusion, the risk factors for stroke in young people are complex and diverse, and effective prevention and treatment of the causes and risk factors is necessary to reduce the occurrence of stroke in young people and improve their lives.