Cerebral vascular events (CVA) have a high prevalence in our environment; they are the first cause of disability and the second cause of death in the world (6.6 million deaths). 71% of all strokes worldwide correspond to the ischemic type, which is defined as an infarction in the brain, spinal cord or retina; The remaining 10-40% are hemorrhagic and are due to rupture of cerebral arteries. Until epidemiological week 35 of 2022, 34,643 cases were reported in Mexico, for this week in 2021, 26,462 cases had been reported. Baja California is among the first three places in the country with the highest number of reported cases, the majority corresponding to the male sex. The key clinical characteristic is the sudden appearance of a focal neurological deficit. Imaging studies such as head computed tomography or magnetic resonance imaging allow us to differentiate the subtype and mechanism of CVD since treatment differs markedly between CVD of ischemic origin and that of hemorrhagic origin. Vitamin B12 or cobalamin is a tetrapyrrole cofactor; One of its functions is to participate in the metabolism of homocysteine, which has been reported in various studies and it has been shown that high levels of this increase the risk of vascular diseases, such as stroke. On the other hand, vitamin B12 deficiency can lead to platelet dysfunction, causing significant bleeding. There are few protocols that have sought the direct association of cobalamin with CVD and even fewer with the hemorrhagic type. This condition is one of the main causes of admission to the Emergency Service of the General Hospital of Mexicali where they are given the necessary attention such as performing imaging studies and taking laboratory samples and based on the results the treatment to be followed is decided; However, measurements of vitamin B12 levels are not performed in this population. If the association is demonstrated, it could be implemented as a preventive measure for cerebral vascular events.

General objective: To demonstrate if there is a difference between serum levels of vitamin B12 in patients with hemorrhagic cerebral vascular event compared to patients with ischemic cerebral vascular event.

Specific objectives

• Describe the characteristics of the study population (sex, age, comorbidities, laboratory diagnoses)
• Determine serum levels of vitamin B12 in patients with cerebral vascular event
• Establish the prevalence of vitamin B12 deficiency in patients with cerebral vascular events.
• Correlations of vitamin B12 deficiency with the severity of the disease
• To establish whether there is a difference in serum vitamin B12 levels between patients with ischemic stroke compared to hemorrhagic stroke.
• Determine if the degree of deficiency correlates with mortality
• Compare vitamin B12 levels by subgroups

STUDY DESIGN This will be a prospective, observational, analytical study of patients admitted to the General Hospital of Mexicali with a diagnosis of ischemic or hemorrhagic stroke.

SOURCE FOR OBTAINING PATIENTS Patients admitted to the adult emergency department of the Mexicali General Hospital with a diagnosis of ischemic or hemorrhagic stroke are included. The information will be collected from the electronic clinical record.

Non-probability sampling for convenience. Select all patients who arrive at the hospital who meet inclusion criteria and do not have any exclusion or elimination criteria.

Inclusion Criteria:

• Age over 18 years
• Have a diagnosis of a cerebral vascular event
• Being a hospitalized patient at the General Hospital of Mexicali

Exclusion Criteria:

• Patients without lab tests during their hospitalization
• Patients without a cranial CT scan

Select all patients who arrive at the hospital who meet inclusion criteria and do not have any exclusion or elimination criteria.