tetano
Editor, Senior Moderator
Drugs Real World Outcomes
. 2026 Jul 13.
doi: 10.1007/s40801-026-00568-4. Online ahead of print.
Pre-existing Comorbidities as Potential Risk Modifiers for New-Onset Myocarditis and Pericarditis following mRNA COVID-19 Vaccination in Males Aged 18-30 in the United States: A Disproportionality Analysis using VAERS Spontaneous Reporting Data
Mohammed Salah Salem[SUP] 1 [/SUP], Yola Moride[SUP] 2 [/SUP], Bernard Bégaud[SUP] 3 [/SUP]
Affiliations
Background: Rare cases of myocarditis and pericarditis following mRNA coronavirus disease-19 (COVID-19) vaccination have been reported, primarily among males under 30 years of age. Although the underlying mechanisms remain unclear, cardiovascular risk factors such as hypertension, diabetes, dyslipidemia, and obesity have been hypothesized as potential contributors. Using the Vaccine Adverse Event Reporting System (VAERS), this study investigated whether these comorbidities were disproportionately reported among young adult males with myocarditis or pericarditis following mRNA COVID-19 vaccination compared with vaccinated and general populations. Additionally, this study represents a novel application of disproportionality principles in spontaneous reporting databases to explore, beyond signal detection, the factors that might be associated with the occurrence of an adverse event.
Methods: An observed-versus-expected analysis was conducted using reports of myocarditis or pericarditis following mRNA COVID-19 vaccination among males aged 18-30 recorded in VAERS between 2021 and 2022. The prevalence of hypertension, diabetes, dyslipidemia, and obesity among reported cases was compared with prevalence estimates derived from epidemiological studies of vaccinated populations and national population statistics. In addition, disproportionality analyses were performed using comparator groups consisting of reports associated with other vaccines and other adverse events following immunization (AEFIs) within VAERS.
Results: A total of 859 eligible reports of myocarditis/pericarditis following mRNA COVID-19 vaccination were identified among males aged 18-30. The prevalence of hypertension, diabetes, dyslipidemia, and obesity was 0.35%, 0.58%, 0.81%, and 1.75%, respectively and was significantly lower than those reported in vaccinated and prepandemic general populations. In disproportionality analyses, myocarditis/pericarditis reports following mRNA vaccination showed higher prevalence of dyslipidemia and obesity, but lower prevalence of hypertension, compared with selected VAERS comparator groups. However, absolute comorbidity prevalence remained low across all groups.
Conclusions: No evidence of a modifying role for hypertension, diabetes, dyslipidemia, or obesity was observed for the increased reporting of myocarditis/pericarditis among young adult males following mRNA COVID-19 vaccination. Despite the limitations inherent to spontaneous reporting systems, this study highlights a novel application of disproportionality-based approaches within VAERS to explore potential risk modifiers of vaccine-related adverse events in a hypothesis-generating manner.
Plain language summary
Rare cases of inflammation of the heart muscle (myocarditis) or of the protective layer around the heart (pericarditis), have been reported after mRNA COVID-19 vaccination, especially in young adult males. This study examined whether common conditions with cardiovascular burden—high blood pressure, diabetes, high cholesterol, and obesity—were more common among males aged 18–30 years who developed myocarditis or pericarditis after mRNA COVID-19 vaccination, which could explain the reason for an increased risk. The study used information from a US vaccine safety monitoring database (VAERS) that collects reports of health problems occurring after vaccination. Researchers compared how often these cardiovascular conditions were reported in young males with myocarditis/pericarditis after mRNA COVID-19 vaccination with how common these conditions are in vaccinated and general US populations. The study found that these conditions were reported less often than expected among myocarditis/pericarditis cases. Additional analyses also showed low reporting of these conditions across other vaccine-related adverse event reports. Overall, the findings do not suggest that high blood pressure, diabetes, high cholesterol, or obesity play a major role in the increased reporting of myocarditis/pericarditis among young adult males following mRNA-based COVID-19 vaccination. The study also highlights a new way of using vaccine safety databases to explore factors that may influence vaccine-related adverse events.
. 2026 Jul 13.
doi: 10.1007/s40801-026-00568-4. Online ahead of print.
Pre-existing Comorbidities as Potential Risk Modifiers for New-Onset Myocarditis and Pericarditis following mRNA COVID-19 Vaccination in Males Aged 18-30 in the United States: A Disproportionality Analysis using VAERS Spontaneous Reporting Data
Mohammed Salah Salem[SUP] 1 [/SUP], Yola Moride[SUP] 2 [/SUP], Bernard Bégaud[SUP] 3 [/SUP]
Affiliations
- PMID: 42440199
- DOI: 10.1007/s40801-026-00568-4
Background: Rare cases of myocarditis and pericarditis following mRNA coronavirus disease-19 (COVID-19) vaccination have been reported, primarily among males under 30 years of age. Although the underlying mechanisms remain unclear, cardiovascular risk factors such as hypertension, diabetes, dyslipidemia, and obesity have been hypothesized as potential contributors. Using the Vaccine Adverse Event Reporting System (VAERS), this study investigated whether these comorbidities were disproportionately reported among young adult males with myocarditis or pericarditis following mRNA COVID-19 vaccination compared with vaccinated and general populations. Additionally, this study represents a novel application of disproportionality principles in spontaneous reporting databases to explore, beyond signal detection, the factors that might be associated with the occurrence of an adverse event.
Methods: An observed-versus-expected analysis was conducted using reports of myocarditis or pericarditis following mRNA COVID-19 vaccination among males aged 18-30 recorded in VAERS between 2021 and 2022. The prevalence of hypertension, diabetes, dyslipidemia, and obesity among reported cases was compared with prevalence estimates derived from epidemiological studies of vaccinated populations and national population statistics. In addition, disproportionality analyses were performed using comparator groups consisting of reports associated with other vaccines and other adverse events following immunization (AEFIs) within VAERS.
Results: A total of 859 eligible reports of myocarditis/pericarditis following mRNA COVID-19 vaccination were identified among males aged 18-30. The prevalence of hypertension, diabetes, dyslipidemia, and obesity was 0.35%, 0.58%, 0.81%, and 1.75%, respectively and was significantly lower than those reported in vaccinated and prepandemic general populations. In disproportionality analyses, myocarditis/pericarditis reports following mRNA vaccination showed higher prevalence of dyslipidemia and obesity, but lower prevalence of hypertension, compared with selected VAERS comparator groups. However, absolute comorbidity prevalence remained low across all groups.
Conclusions: No evidence of a modifying role for hypertension, diabetes, dyslipidemia, or obesity was observed for the increased reporting of myocarditis/pericarditis among young adult males following mRNA COVID-19 vaccination. Despite the limitations inherent to spontaneous reporting systems, this study highlights a novel application of disproportionality-based approaches within VAERS to explore potential risk modifiers of vaccine-related adverse events in a hypothesis-generating manner.
Plain language summary
Rare cases of inflammation of the heart muscle (myocarditis) or of the protective layer around the heart (pericarditis), have been reported after mRNA COVID-19 vaccination, especially in young adult males. This study examined whether common conditions with cardiovascular burden—high blood pressure, diabetes, high cholesterol, and obesity—were more common among males aged 18–30 years who developed myocarditis or pericarditis after mRNA COVID-19 vaccination, which could explain the reason for an increased risk. The study used information from a US vaccine safety monitoring database (VAERS) that collects reports of health problems occurring after vaccination. Researchers compared how often these cardiovascular conditions were reported in young males with myocarditis/pericarditis after mRNA COVID-19 vaccination with how common these conditions are in vaccinated and general US populations. The study found that these conditions were reported less often than expected among myocarditis/pericarditis cases. Additional analyses also showed low reporting of these conditions across other vaccine-related adverse event reports. Overall, the findings do not suggest that high blood pressure, diabetes, high cholesterol, or obesity play a major role in the increased reporting of myocarditis/pericarditis among young adult males following mRNA-based COVID-19 vaccination. The study also highlights a new way of using vaccine safety databases to explore factors that may influence vaccine-related adverse events.