Stroke Among SARS-CoV-2 Vaccine Recipients in Mexico: A Nationwide Descriptive Study.

BACKGROUND AND OBJECTIVES: Information on stroke among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines remains scarce. We report stroke incidence as an adverse event following immunization (AEFI) among recipients of 79,399,446 doses of 6 different SARS-CoV-2 vaccines (BNT162b2, ChAdOx1 nCov-19, Gam-COVID-Vac, CoronaVac, Ad5-nCoV, and Ad26.COV2-S) between December 24, 2020, and August 31, 2021, in Mexico. METHODS: This retrospective descriptive study analyzed stroke incidence per million doses among hospitalized adult patients (≥18 years) during an 8-month interval. According to the World Health Organization, AEFIs were defined as clinical events occurring within 30 days after immunization and categorized as either nonserious or serious, depending on severity, treatment, and hospital admission requirements. Acute ischemic stroke (AIS), intracerebral hemorrhage (ICH), subarachnoid hemorrhage (SAH), and cerebral venous thrombosis (CVT) cases were collected through a passive epidemiologic surveillance system in which local health providers report potential AEFI to the Mexican General Board of Epidemiology. Data were captured with standardized case report formats by an ad hoc committee appointed by the Mexican Ministry of Health to evaluate potential neurologic AEFI against SARS-COV-2. RESULTS: We included 56 patients (31 female patients [55.5%]) for an overall incidence of 0.71 cases per 1,000,000 administered doses (95% CI 0.54-0.92). Median age was 65 years (interquartile range [IQR] 55-76 years); median time from vaccination to stroke (of any subtype) was 2 days (IQR 1-5 days). In 27 (48.2%) patients, the event was diagnosed within the first 24 hours after immunization. The most frequent subtype was AIS in 43 patients (75%; 0.54 per 1,000,000 doses, 95% CI 0.40-0.73), followed by ICH in 9 (16.1%; 0.11 per 1,000,000 doses, 95% CI 0.06-0.22) and SAH and CVT, each with 2 cases (3.6%; 0.03 per 1,000,000 doses, 95% CI 0.01-0.09). Overall, the most common risk factors were hypertension in 33 (58.9%) patients and diabetes in 22 (39.3%). Median hospital length of stay was 6 days (IQR 4-13 days). At discharge, functional outcome was good (modified Rankin Scale score 0-2) in 41.1% of patients; in-hospital mortality rate was 21.4%. DISCUSSION: Stroke is an exceedingly rare AEFI against SARS-CoV-2. Preexisting stroke risk factors were identified in most patients. Further research is needed to evaluate causal associations between SARS-COV-2 vaccines and stroke.

Demographic and clinical characterization of multiple sclerosis in Mexico: The REMEMBer study.

BACKGROUND: Multiple sclerosis (MS) is a chronic neurodegenerative disease of the central nervous system with high prevalence in young adults around the world. The vast majority of epidemiological studies and statistics are based on European and American data, so most clinical guidelines and medical consensus are based on this information. There is very limited evidence in Mexico regarding demographic and clinical aspects of MS. Therefore, this study comprehensively described the epidemiological and clinical features of MS in a large cohort of patients from eight tertiary-level centers in Mexico. METHODS: A cross-sectional multicenter study was conducted. A group of neurologists, the "Registro Mexicano de Esclerosis Multiple" (REMEMBer) group, compiled the information of MS patients (January to December 2019) from eight tertiary-level centers. Clinical and demographic data were extracted. RESULTS: A total of 1,185 patients were included. The mean age was 40.65 ± 11.43 years old. Women represented more than half of the whole cohort (64.9% vs. 35.1%). Of the whole cohort, forty-three percent of MS patients had a relative with at least one autoimmune disease (MS: 24%, other autoimmune disorders: 74.9%) or thyroid disease (28%). Furthermore, the mean age of clinical onset was 31.23 ± 9.71 (range: 16-68) years old, and the disease duration was 9.33 ± 7.25 (0.46-40.19) years. The most prevalent phenotype of MS was relapsing-remitting (87.76%). Primary (1.18%) and secondary (9.11%) progressive, as well as clinically isolated syndrome (CIS, 1.43%), were also found. Clinical phenotypes (facial, hearing, and speech disorders, and movement impairment and ataxia) and the frequency of thyroid disorders were different between genders. CONCLUSION: In Mexico, the frequency of MS seems to be higher in the female gender (2:1 women/men ratio) compared to other series. In addition, there was a predominance of facial, hearing and speech disorders, as well as movement impairment and ataxia. Thyroid diseases were more common in women with multiple sclerosis than men.