Global burden of vaccine-associated anaphylaxis and their related vaccines, 1967-2023: A comprehensive analysis of the international pharmacovigilance database

Vaccines and allergy: Back to the right places

Hypersensitivity reactions represent one of the most common causes of hesitancy for adherence to national vaccination programs. The majority of hypersensitivity reactions after vaccination are mild, and anaphylaxis is reported to be rare, although it remains challenging to estimate the frequency attributed to each single vaccine, either because of the lower number of administered doses of less common vaccines, or the administration of simultaneous vaccine in most of the vaccination programs. Although literature remains scattered, international consensus guides clinicians in identifying patients who might need the administration of vaccines in protected environments due to demonstrated hypersensitivity to vaccine components or adjuvants. Here we provide the current guidance on hypersensitivity reactions to vaccines and on vaccination of children with allergy disorders.

Global burden of ADHD medication-associated cardiovascular disease, 1967-2023: A comparative analysis using the WHO pharmacovigilance database

BACKGROUND

Despite the widespread use of attention-deficit hyperactivity disorder (ADHD) medications and their known sympathomimetic effects on the cardiovascular system, cardiovascular risk assessment of these medications using comprehensive global data is limited. This study investigated the association between individual ADHD medications and cardiovascular disease (CVD) using global pharmacovigilance data.

METHODS

Reports from the World Health Organization international pharmacovigilance database were utilized (1967-2023; total reports, n=131,255,418). Reporting odds ratios (ROR), and information components (IC) were calculated to evaluate the association between each medication and specific CVDs.

RESULTS

We identified 13,344 CVD cases related to ADHD medications out of 146,489 cases of all reports on ADHD medications. Cumulative reports on ADHD medications have shown a steady increase, notably in adults since 2010. ADHD medications were associated with a higher risk of CVD overall (ROR [95 % CI], 1.60 [1.58-1.63]; IC [IC0.25], 0.63 [0.60]), with a higher association observed in females than in males. Among specific CVDs, all drugs were associated with an increased risk of torsade de pointes/QT prolongation, cardiomyopathy, and myocardial infarction. Conversely, heart failure, stroke, and cardiac death/shock were exclusively associated with amphetamines. Lisdexamfetamine showed a weaker association with all CVDs compared to amphetamines, and methylphenidate exhibited the lowest overall association with CVD. Atomoxetine had the second-highest association with torsade de pointes/QT prolongation.

CONCLUSIONS

The associations between CVDs and ADHD medications vary, with amphetamines posing a higher risk, while lisdexamfetamine and methylphenidate exhibit better safety profiles.

Global public concern of childhood and adolescence suicide: a new perspective and new strategies for suicide prevention in the post-pandemic era

BACKGROUND

Suicide is the second leading cause of death in young people worldwide and is responsible for about 52,000 deaths annually in children and adolescents aged 5-19 years. Familial, social, psychological, and behavioral factors play important roles in suicide risk. As traumatic events such as the COVID-19 pandemic may contribute to suicidal behaviors in young people, there is a need to understand the current status of suicide in adolescents, including its epidemiology, associated factors, the influence of the pandemic, and management initiatives.

DATA SOURCES

We investigated global and regional suicide mortality rates among children and adolescents aged 5-19 years using data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. The suicide mortality rates from 1990 to 2019 were examined in 204 countries and territories across six World Health Organization (WHO) regions. Additionally, we utilized electronic databases, including PubMed/MEDLINE and Scopus, and employed various combinations of terms such as "suicide", "adolescents", "youth", "children", "risk factors", "COVID-19 pandemic", "prevention", and "intervention" to provide a narrative review on suicide within the pediatric population in the post-pandemic era.

RESULTS

Despite the decreasing trend in the global suicide mortality rate from 1990 to 2019, it remains high. The mortality rates from suicide by firearms or any other specified means were both greater in males. Additionally, Southeast Asia had the highest suicide rate among the six WHO regions. The COVID-19 pandemic seems to contribute to suicide risk in young people; thus, there is still a strong need to revisit appropriate management for suicidal children and adolescents during the pandemic.

CONCLUSIONS

The current narrative review integrates up-to-date knowledge on suicide epidemiology and the effects of the COVID-19 pandemic, risk factors, and intervention strategies. Although numerous studies have characterized trends in suicide among young people during the pre-pandemic era, further studies are required to investigate suicide during the pandemic and new strategies for suicide prevention in the post-pandemic era. It is necessary to identify effective prevention strategies targeting young people, particularly those at high risk, and successful treatment for individuals already manifesting suicidal behaviors. Care for suicidal children and adolescents should be improved with parental, school, community, and clinical involvement.

Global burden of vaccine-associated hepatobiliary and gastrointestinal adverse drug reactions, 1967-2023: A comprehensive analysis of the international pharmacovigilance database

Although previous studies have focused on hepatobiliary and gastrointestinal adverse drug reactions (ADRs) associated with COVID-19 vaccines, literature on such ADRs with other vaccines is limited, particularly on a global scale. Therefore, we aimed to investigate the global burden of vaccine-associated hepatobiliary and gastrointestinal ADRs and identify the vaccines implicated in these occurrences. This study utilized data from the World Health Organization (WHO) international pharmacovigilance database to extract reports of vaccine-associated hepatobiliary and gastrointestinal ADRs from 1967 to 2023 (total reports = 131 255 418). Through global reporting counts, reported odds ratios (ROR) with 95% confidence interval (CI), and information components (IC) with IC0.25, the study examined the association between 16 vaccines and the incidence of hepatobiliary and gastrointestinal ADRs across 156 countries. Of the 6 842 303 reports in the vaccine-associated ADRs, 10 786 reports of liver injury, 927 870 reports of gastrointestinal symptoms, 2978 reports of pancreas and bile duct injury, and 96 reports of intra-abdominal hemorrhage between 1967 and 2023 were identified. Most hepatobiliary and gastrointestinal ADRs surged after 2020, with the majority of reports attributed to COVID-19 messenger RNA (mRNA) vaccines. Hepatitis A vaccines exhibited the highest association with liver injury (ROR [95% CI]: 10.30 [9.65-10.99]; IC [IC0.25]: 3.33 [3.22]), followed by hepatitis B, typhoid, and rotavirus. Specifically, ischemic hepatitis had a significant association with both Ad5-vectored and mRNA COVID-19 vaccines. Gastrointestinal symptoms were associated with all vaccines except for tuberculosis vaccines, particularly with rotavirus (11.62 [11.45-11.80]; 3.05 [3.03]) and typhoid (11.02 [10.66-11.39]; 3.00 [2.96]). Pancreas and bile duct injury were associated with COVID-19 mRNA (1.99 [1.89-2.09]; 0.90 [0.83]), MMR (measles, mumps, and rubella), and papillomavirus vaccines. For intra-abdominal hemorrhage, inactivated whole-virus COVID-19 vaccines (3.93 [1.86-8.27]; 1.71 [0.41]) had the highest association, followed by COVID-19 mRNA (1.81 [1.42-2.29]; 0.77 [0.39]). Most of these ADRs had a short time to onset, within 1 day, and low mortality rate. Through a global scale database, the majority of ADRs occurred within 1 day, emphasizing the importance of healthcare workers' vigilant monitoring and timely management.

Comorbid physical health outcomes in patients with bipolar disorder: An umbrella review of systematic reviews and meta-analyses

BACKGROUND

Although several meta-analyses have examined the association between bipolar disorder (BD) and its comorbid health outcomes, this evidence has not been comprehensively assembled.

OBJECTIVE

We aimed to systematically review existing meta-analyses based on multiple physical outcomes and validate the evidence level by examining the existing certainty of evidence.

METHODS

We systematically searched databases, including PubMed/MEDLINE, Embase, Google Scholar, and CINAHL, for articles published up to July 2023. We included meta-analyses of cohort, case-control, and/or cross-sectional studies investigating any comorbid health outcomes in patients with BD. We conducted quality assessments of the included meta-analysis using AMSTAR2. The credibility of findings was categorized into five levels of class and quality of evidence (CE), including convincing, highly suggestive, suggestive, weak, or not significant.

RESULTS

We analyzed 12 meta-analyses, including 145 original articles, covering 14 unique health outcomes with over 60 million participants across 29 countries and five continents. Among 14 health outcomes, BD was significantly associated with eight comorbid health outcomes, including dementia (equivalent odds ratio [eOR], 2.96 [95 % confidence intervals {CI}, 1.69-5.17]; CE=suggestive), Parkinson's disease (3.35 [1.72-6.53]; CE=suggestive), asthma (1.86 [1.42-2.42]; CE=weak), toxoplasmosis (1.69 [1.21-2.37]; CE=weak), hypertension (1.28 [1.02-1.60]; CE=convincing), breast cancer (1.33 [1.15-1.55]; CE=weak), obesity (1.64 [1.30-1.99]; CE=suggestive), and type 2 diabetes mellitus (1.98 [1.55-2.52]; CE=weak).

CONCLUSION

Individuals with BD are predisposed to numerous comorbid physical conditions, though these links are supported by various evidence levels and necessitate further studies. It is imperative that physicians be aware of these potential comorbidities in patients with BD and take proactive measures to manage them.

National trends in sexual intercourse and usage of contraception among Korean adolescents

BACKGROUND

The exact influence of the COVID-19 pandemic on sexual intercourse and usage of contraception remains largely uncharted territory. To bridge this gap in knowledge, we conducted a comprehensive, cross-sectional examination of long-term trends in the prevalence of sexual intercourse and usage of contraception among South Korean adolescents from 2006 to 2022.

METHODS

In our research, we drew upon data encompassing 1,138,799 South Korean adolescents aged 12 to 18 years, derived from the Korean Youth Risk Behavior Web-based Survey (KYRBS) over a period spanning from 2006 to 2022. We focused on the prevalence of sexual intercourse, contraception utilization, and the underlying associated factors among this demographic. The KYRBS data was collected using a complex sampling strategy to determine the national prevalence estimates and shifts in prevalence before (2006-2019) and during (2020-2022) the COVID-19 pandemic era.

RESULTS

During the pre-pandemic period, a decrease in adolescent sexual intercourse was observed (6.34% in 2006, 5.53% in 2012, and 5.87% in 2019). However, in the post-pandemic period (2020-2022), there was a surge in sexual intercourse (4.55% in 2020 and 6.20% in 2022). This evident alteration in sexual intercourse trajectory between pre- and post-pandemic periods was statistically significant [βdiff, 0.950; 95% confidence interval (CI), 0.756-1.144]. Regarding contraceptive use among South Korean adolescents, there was an increase in the pre-COVID-19 pandemic phase across all demographic segments (14.61% in 2006, 22.30% in 2012, and 47.69% in 2022) but a notable decline when compared with the pre- and post-pandemic periods (βdiff, - 0.319; 95% CI, - 0.454 to - 0.184). Additionally, during the study period, a decrease in sexual intercourse was observed in the pre-pandemic period (β, - 0.129; 95% CI, - 0.148 to - 0.110), followed by an increase in the post-pandemic period (β, 0.821; 95% CI, 0.627 to 1.014). This shift is highlighted by an effect size of 0.96 [weighted odds ratio (wOR); 95% CI, 0.92 to 1.00], indicating a substantial change in adolescent sexual behaviors across study periods.

CONCLUSIONS

The increase in sexual intercourse and decrease in usage of contraception observed in our study between the pre- and post-COVID-19 periods suggests a potential threat to sexual health among South Korean adolescents. This trend emphasizes the ongoing necessity of raising awareness about adolescent sexual behavior in South Korea.

Global and regional burden of vaccine-induced thrombotic thrombocytopenia, 1969-2023: Comprehensive findings with critical analysis of the international pharmacovigilance database

OBJECTIVE

The scarcity of studies on vaccine-induced thrombosis and thrombocytopenia syndrome (TTS) limits the comprehensive understanding of vaccine safety on a global scale. Therefore, the objective of this study is to assess the global burden of vaccine-induced TTS, identify the vaccines most associated with it, and suggest clinical implications regarding vaccination.

METHODS

This study employed the World Health Organization international pharmacovigilance database, extracting records of vaccine-induced immune thrombotic thrombocytopenia from 1969 to 2023 (total reports, n > 130 million). Global reporting counts, reported odds ratios (ROR), and information components (IC) were calculated to identify the association between 19 vaccines and the occurrence of vaccine-induced TTS across 156 countries.

RESULTS

We identified 24 233 cases (male, n = 11 559 [47.7%]) of vaccine-induced TTS among 404 388 reports of all-cause TTS. There has been a significant increase in reports of vaccine-induced TTS events over time, with a noteworthy surge observed after 2020, attributed to cases of TTS associated with COVID-19 vaccines. Measles, mumps, and rubella (MMR) vaccines were associated with most TTS reports (ROR [95% confidence interval], 2.87 [2.75-3.00]; IC [IC0.25], 1.51 [1.43]), followed by hepatitis B (HBV, 2.23 [2.07-2.39]; 1.15 [1.03]), rotavirus diarrhea (1.95 [1.78-2.13]; 0.81 [0.53]), encephalitis (1.80 [1.50-2.16]; 0.84 [0.53]), hepatitis A (1.67 [1.50-1.86]; 0.73 [0.55]), adenovirus Type 5 vector-based (Ad5-vectored) COVID-19 (1.64 [1.59-1.68]; 0.69 [0.64]), pneumococcal (1.57 [1.49-1.66]; 0.65 [0.56]), and typhoid vaccines (1.41 [1.12-1.78]; 0.49 [0.11]). Concerning age and sex-specific risks, reports of vaccine-induced TTS were more associated with females and younger age groups. The age group between 12 and 17 years exhibited significant sex disproportion. Most of these adverse events had a short time to onset (days; mean [SD], 4.99 [40.30]) and the fatality rate was 2.20%, the highest rate observed in the age group over 65 years (3.79%) and lowest in the age group between 0 and 11 years (0.31%).

CONCLUSION

A rise in vaccine-induced TTS reports, notably MMR, HBV, and rotavirus diarrhea vaccines, was particularly related to young females. Ad5-vectored COVID-19 vaccines showed comparable or lower association with TTS compared to other vaccines. Despite the rarity of these adverse events, vigilance is essential as rare complications can be fatal, especially in older groups. Further studies with validated reporting are imperative to improve the accuracy of assessing the vaccine-induced TTS for preventive interventions and early diagnosis.

Global estimates on the reports of vaccine-associated myocarditis and pericarditis from 1969 to 2023: Findings with critical reanalysis from the WHO pharmacovigilance database

Due to the limitation of previous studies examining adverse reports of myocarditis and pericarditis associated with vaccines other than the COVID-19 vaccine, there are challenges in establishing a comprehensive understanding of vaccine safety on a global scale. Hence, the objective of this study was to examine the worldwide burden of vaccine-associated pericarditis and myocarditis and the vaccines associated with these indications. This study utilized the World Health Organization international pharmacovigilance database, from which records of vaccine-associated pericarditis and myocarditis between 1969 and 2023 were extracted (over 130 million reports). We calculated global reporting counts, reported odds ratios (RORs), and information components (ICs) to discern the association between 19 vaccines and the occurrence of pericarditis and myocarditis across 156 countries and territories. We identified 49 096 reports (male, n = 30 013) of vaccine-associated pericarditis and myocarditis among 73 590 reports of all-cause pericarditis and myocarditis. There has been a significant increase in reports of vaccine-related cardiac adverse events over time, with a noteworthy surge observed after 2020, attributed to cases of pericarditis associated with COVID-19 mRNA vaccines. Smallpox vaccines were associated with most pericarditis and myocarditis reports (ROR: 73.68 [95% CI, 67.79-80.10]; IC [IC0.25]: 6.05 [5.91]), followed by COVID-19 mRNA vaccine (37.77 [37.00-38.56]; 3.07 [3.05]), anthrax vaccine (25.54 [22.37-29.16]; 4.58 [4.35]), typhoid vaccine (6.17 [5.16-7.38]; 2.59 [2.29]), encephalitis vaccine (2.00 [1.48-2.71]; 0.99 [0.47]), influenza vaccine (1.87 [1.71-2.04]; 0.90 [0.75]), and Ad5-vectored COVID-19 vaccine (1.40 [1.34-1.46]; 0.46 [0.39]). Concerning age and sex-specific risks, reports of vaccine-associated pericarditis and myocarditis were more prevalent among males and in older age groups. The age group between 12 and 17 years exhibited significant sex disproportion. Most of these adverse events had a short time to onset (median time: 1 day) and fatality rate was 0.44%. Our analysis of global data revealed an increase in pericarditis and myocarditis reports associated with vaccines, particularly live vaccines like smallpox and anthrax, notably in young males. While these adverse events are generally rare and mild, caution is warranted, especially for healthcare workers, due to potential myocardial injury-related in-hospital mortality. Further study with validated reporting is crucial to enhance accuracy in evaluating the correlation between vaccines and cardiac conditions for preventive measures.

Global and regional burden of vaccine-associated facial paralysis, 1967-2023: Findings from the WHO international pharmacovigilance database

The scarce and conflicting data on vaccine-associated facial paralysis limit our understanding of vaccine safety on a global scale. Therefore, this study aims to evaluate the global burden of vaccine-associated facial paralysis and to identify the extent of its association with individual vaccines, thereby contributing to the development of a more effective vaccination program. We used data on vaccine-associated facial paralysis from 1967 to 2023 (total reports, n = 131 255 418 418) from the World Health Organization International Pharmacovigilance Database. Global reporting counts, reported odds ratios (ROR), and information components (ICs) were computed to elucidate the association between the 16 vaccines and the occurrence of vaccine-associated facial paralysis across 156 countries. We identified 26 197 reports (men, n = 10 507 [40.11%]) of vaccine-associated facial paralysis from 49 537 reports of all-cause facial paralysis. Vaccine-associated facial paralysis has been consistently reported; however, a pronounced increase in reported incidence has emerged after the onset of the coronavirus disease 2019 (COVID-19) pandemic, which is attributable to the COVID-19 mRNA vaccine. Most vaccines were associated with facial paralysis, with differing levels of association, except for tuberculosis vaccines. COVID-19 mRNA vaccines had the highest association with facial paralysis reports (ROR, 28.31 [95% confidence interval, 27.60-29.03]; IC, 3.37 [IC0.25, 3.35]), followed by encephalitis, influenza, hepatitis A, papillomavirus, hepatitis B, typhoid, varicella-zoster, meningococcal, Ad-5 vectored COVID-19, measles, mumps and rubella, diphtheria, tetanus toxoids, pertussis, polio, and Hemophilus influenza type b, pneumococcal, rotavirus diarrhea, and inactivated whole-virus COVID-19 vaccines. Concerning age- and sex-specific risks, vaccine-associated facial paralysis was more strongly associated with older age groups and males. The serious adverse outcome and death rate of vaccine-associated facial paralysis were extremely low (0.07% and 0.00%, respectively). An increase in vaccine-induced facial paralysis, primarily owing to COVID-19 mRNA vaccines, was observed with most vaccines, except tuberculosis vaccines. Given the higher association observed in the older and male groups with vaccine-associated facial paralysis, close monitoring of these demographics when administering vaccines that are significantly associated with adverse reactions is crucial.

Analysis of Allergy and Hypersensitivity Reactions to COVID-19 Vaccines According to the EudraVigilance Database

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic presented a new challenge in modern medicine: the development of vaccines was followed by massive population vaccinations. A few reports on post-vaccination allergic reactions have made patients and medical personnel uneasy as to COVID-19 vaccines' allergic potential. Most of the studies in this area to date have been small, and some that were based on global databases skipped most of the allergic diseases and concentrated only on anaphylaxis. We aimed to analyze the incidence of serious allergic reactions based on the EudraVigilance (EV) database, regardless of the reported symptoms and allergy mechanism.

METHODS

The total number of administrated vaccine doses was extracted on 5 October 2023 from Vaccine Tracker and included all administrations since vaccinations began in the European Economic Area (EEA). Data on serious allergic reactions to COVID-19 vaccines were extracted from the EudraVigilance database with the same time point. The code names of 147 allergic symptoms or diseases were used.

RESULTS

The frequency of serious allergic reactions per 100,000 administered vaccine doses was 1.53 for Comirnaty, 2.16 for Spikevax, 88.6 for Vaxzevria, 2.11 for Janssen, 7.9 for Novavax, 13.3 for VidPrevtyn Beta, and 3.1 for Valneva. The most prevalent reported reactions were edema (0.46) and anaphylaxis (0.40). Only 6% of these reactions were delayed hypersensitivity-oriented.

CONCLUSIONS

The overall frequency of potential serious allergic reactions to COVID-19 is very rare. Therefore, COVID-19 vaccines seem to be safe for human use. The lowest frequency of allergic reaction was observed for Comirnaty and the highest for Vaxzevria.

National trends of allergic diseases and pandemic-related factors among individuals with obesity in South Korea: A nationwide representative serial study, 2005-2021

Background

Although obesity is known to be related to allergic diseases, few studies have investigated the prevalence of allergic diseases in individuals with obesity, especially during the COVID-19 pandemic. Thus, this study aimed to analyze national trends of allergic diseases among individuals with obesity and sociodemographic factors.

Methods

This study used data from the Korea National Health and Nutrition Examination Survey to examine the prevalence of allergic diseases among individuals with obesity in South Korea from 2005 to 2021. A nationally representative sample of 118,275 participants aged over 2 years or above was divided into six groups for analysis. This study used weighted multivariate regression analysis to examine the estimates of related factors. It assessed the weighted odds ratios or β-coefficients for these factors across different categories, including age, sex, region of residence, education level, household income, and body mass index for the entire population.

Results

All allergic diseases showed a general upward trend from 2005 to 2021, but each disease showed different prevalence trends when compared by age. Before the pandemic, those aged ≤39 years had an increasing trend for asthma and AD, but those aged ≥40 years had a decreasing trend. For asthma, β-coefficients were 0.629 (95 % CI, 0.299 to 0.958) for 19-39 years, -0.245 (-0.450 to -0.040) for 40-59 years, and -0.668 (-1.024 to -0.313) for ≥60 years. For AD, β-coefficients were 2.514 (1.258-3.769) in those aged 2-18 years, 0.630 (0.173-1.086) in those aged 19-39 years, -0.458 (-0.648 to -0.268) in those aged 40-59 years, and -0.253 (-0.454 to -0.052) in those aged ≥60 years. However, for both asthma and AD, there were no significant changes in prevalence during the pandemic. In the case of AR, trends were different from those of asthma and AD. Before the pandemic, AR showed an increasing trend in those aged ≤39 years and those aged ≥40 years: β-coefficients were 3.067 (2.344-3.790) in 19-39 years, 2.051 (1.609-2.493) in 40-59 years, and 1.173 (0.820-1.526) in ≥60 years. During the pandemic, there was an increasing trend only among those aged 40-59, with no significant changes in other age groups: β-coefficients were 1.438 (0.065-2.811) in 40-59 years.

Conclusions

From 2005 to 2021, all allergic diseases (asthma, AD, and AR) increased overall, but with different age-related trends. No significant link was found between COVID-19 and allergic diseases, possibly due to preventive measures like mask-wearing and social distancing. Anxiety about accessing healthcare during the pandemic likely contributed to a decline in allergy diagnoses, highlighting the need for comprehensive strategies to manage and prevent allergic diseases.

Prenatal and postnatal factors associated with sudden infant death syndrome: an umbrella review of meta-analyses

BACKGROUND

Comprehensive quantitative evidence on the risk and protective factors for sudden infant death syndrome (SIDS) effects is lacking. We investigated the risk and protective factors related to SIDS.

METHODS

We conducted an umbrella review of meta-analyses of observational and interventional studies assessing SIDS-related factors. PubMed/MEDLINE, Embase, EBSCO, and Google Scholar were searched from inception until January 18, 2023. Data extraction, quality assessment, and certainty of evidence were assessed by using A Measurement Tool Assessment Systematic Reviews 2 following PRISMA guidelines. According to observational evidence, credibility was graded and classified by class and quality of evidence (CE; convincing, highly suggestive, suggestive, weak, or not significant). Our study protocol was registered with PROSPERO (CRD42023458696). The risk and protective factors related to SIDS are presented as equivalent odds ratios (eORs).

RESULTS

We identified eight original meta-analyses, including 152 original articles, covering 12 unique risk and protective factors for SIDS across 21 countries/regions and five continents. Several risk factors, including prenatal drug exposure [eOR = 7.84 (95% CI = 4.81-12.79), CE = highly suggestive], prenatal opioid exposure [9.55 (95% CI = 4.87-18.72), CE = suggestive], prenatal methadone exposure [9.52 (95% CI = 3.34-27.10), CE = weak], prenatal cocaine exposure [4.38 (95% CI = 1.95-9.86), CE = weak], prenatal maternal smoking [2.25 (95% CI = 1.95-2.60), CE = highly suggestive], postnatal maternal smoking [1.97 (95% CI = 1.75-2.22), CE = weak], bed sharing [2.89 (95% CI = 1.81-4.60), CE = weak], and infants found with heads covered by bedclothes after last sleep [11.01 (95% CI = 5.40-22.45), CE = suggestive], were identified. On the other hand, three protective factors, namely, breastfeeding [0.57 (95% CI = 0.39-0.83), CE = non-significant], supine sleeping position [0.48 (95% CI = 0.37-0.63), CE = suggestive], and pacifier use [0.44 (95% CI = 0.30-0.65), CE = weak], were also identified.

CONCLUSIONS

Based on the evidence, we propose several risk and protective factors for SIDS. This study suggests the need for further studies on SIDS-related factors supported by weak credibility, no association, or a lack of adequate research.

Global burden of vaccine-associated alopecia, 1979-2023: a comprehensive analysis of the international pharmacovigilance database

While global concern over vaccine-associated alopecia has been gradually increasing, it has also been reported that alopecia, classified as an autoimmune disease, can manifest as an immune-related side-effect caused by vaccinations. However, comprehensive research on vaccine-associated alopecia has been limited. Therefore, we carried out a comprehensive analysis using information from VigiBase (1979–2023) from more than 156 countries, managed by the WHO and the Uppsala Monitoring Centre. Thus, this global pharmacovigilance study of vaccine-associated alopecia, encompassing all age and sex groups, provides international and comprehensive evidence that substantiates the overall real-world impact of vaccines.

Incident allergic diseases in post-COVID-19 condition: multinational cohort studies from South Korea, Japan and the UK

As mounting evidence suggests a higher incidence of adverse consequences, such as disruption of the immune system, among patients with a history of COVID-19, we aimed to investigate post-COVID-19 conditions on a comprehensive set of allergic diseases including asthma, allergic rhinitis, atopic dermatitis, and food allergy. We used nationwide claims-based cohorts in South Korea (K-CoV-N; n = 836,164; main cohort) and Japan (JMDC; n = 2,541,021; replication cohort A) and the UK Biobank cohort (UKB; n = 325,843; replication cohort B) after 1:5 propensity score matching. Among the 836,164 individuals in the main cohort (mean age, 50.25 years [SD, 13.86]; 372,914 [44.6%] women), 147,824 were infected with SARS-CoV-2 during the follow-up period (2020-2021). The risk of developing allergic diseases, beyond the first 30 days of diagnosis of COVID-19, significantly increased (HR, 1.20; 95% CI, 1.13-1.27), notably in asthma (HR, 2.25; 95% CI, 1.80-2.83) and allergic rhinitis (HR, 1.23; 95% CI, 1.15-1.32). This risk gradually decreased over time, but it persisted throughout the follow-up period (≥6 months). In addition, the risk increased with increasing severity of COVID-19. Notably, COVID-19 vaccination of at least two doses had a protective effect against subsequent allergic diseases (HR, 0.81; 95% CI, 0.68-0.96). Similar findings were reported in the replication cohorts A and B. Although the potential for misclassification of pre-existing allergic conditions as incident diseases remains a limitation, ethnic diversity for evidence of incident allergic diseases in post-COVID-19 condition has been validated by utilizing multinational and independent population-based cohorts.

Global burden of vaccine-associated multiple sclerosis, 1967-2022: A comprehensive analysis of the international pharmacovigilance database

Vaccine-associated multiple sclerosis (MS) is rare, with insufficient evidence from case reports. Given the scarcity of large-scale data investigating the association between vaccine administration and adverse events, we investigated the global burden of vaccine-associated MS and potential related vaccines from 1967 to 2022. Reports on vaccine-associated MS between 1967 and 2022 were obtained from the World Health Organization International Pharmacovigilance Database (total number of reports = 120 715 116). We evaluated global reports, reporting odds ratio (ROR), and information components (IC) to investigate associations between 19 vaccines and vaccine-associated MS across 156 countries and territories. We identified 8288 reports of vaccine-associated MS among 132 980 cases of all-cause MS. The cumulative number of reports on vaccine-associated MS gradually increased over time, with a substantial increase after 2020, owing to COVID-19 mRNA vaccine-associated MS. Vaccine-associated MS develops more frequently in males and adolescents. Nine vaccines were significantly associated with higher MS reporting, and the highest disproportional associations were observed for hepatitis B vaccines (ROR 19.82; IC025 4.18), followed by encephalitis (ROR 7.42; IC025 2.59), hepatitis A (ROR 4.46; IC025 1.95), and papillomavirus vaccines (ROR 4.45; IC025 2.01). Additionally, MS showed a significantly disproportionate signal for COVID-19 mRNA vaccines (ROR 1.55; IC025 0.52). Fatal clinical outcomes were reported in only 0.3% (21/8288) of all cases of vaccine-associated MS. Although various vaccines are potentially associated with increased risk of MS, we should be cautious about the increased risk of MS following vaccination, particularly hepatitis B and COVID-19 mRNA vaccines, and should consider the risk factors associated with vaccine-associated MS.

Global prevalence of functional dyspepsia according to Rome criteria, 1990-2020: a systematic review and meta-analysis

Although functional dyspepsia (FD) is a common functional gastroduodenal disorder with a high socioeconomic burden, little is known about its global prevalence. Thus, we performed a comprehensive study to estimate long-term trends in the prevalence of FD. We searched PubMed/MEDLINE, Embase, and Google Scholar from 1990 to 2022 for population-based studies that reported the prevalence of FD in adults (≥ 18 years old) according to Rome I, II, III, or IV criteria. The prevalence of FD was extracted from included studies to obtain pooled prevalence with 95% confidence intervals (CI) and 95% prediction intervals. Subgroup analysis was performed according to certain characteristics, including geographic region. A total of 44 studies met the eligibility criteria, including 256,915 participants from 40 countries across six continents. The overall global pooled prevalence of FD was 8.4% (95% CI 7.4-.9.5). The prevalence was the highest in Rome I (11.9%; 95% CI 5.1-25.4) and lowest in Rome IV (6.8%; 95% CI 5.8-7.9). Developing countries showed a higher prevalence than developed countries (9.1% versus 8.0%), and prevalence was higher in women, irrespective of the definition used (9.0% versus 7.0%). The pooled prevalence gradually decreased from 1990 to 2020 (12.4% [8.2-18.3] in 1990-2002 versus 7.3% [6.1-8.7] in 2013-2020). The prevalence of FD differs by country, economic status, geographical region, and sex, and the global prevalence has been gradually declining. Despite the heterogeneity of sample population, our study estimates the current global burden of FD and provides information to heath care policy decisions.

Machine Learning-Based Prediction of Suicidality in Adolescents With Allergic Rhinitis: Derivation and Validation in 2 Independent Nationwide Cohorts

BACKGROUND

Given the additional risk of suicide-related behaviors in adolescents with allergic rhinitis (AR), it is important to use the growing field of machine learning (ML) to evaluate this risk.

OBJECTIVE

This study aims to evaluate the validity and usefulness of an ML model for predicting suicide risk in patients with AR.

METHODS

We used data from 2 independent survey studies, Korea Youth Risk Behavior Web-based Survey (KYRBS; n=299,468) for the original data set and Korea National Health and Nutrition Examination Survey (KNHANES; n=833) for the external validation data set, to predict suicide risks of AR in adolescents aged 13 to 18 years, with 3.45% (10,341/299,468) and 1.4% (12/833) of the patients attempting suicide in the KYRBS and KNHANES studies, respectively. The outcome of interest was the suicide attempt risks. We selected various ML-based models with hyperparameter tuning in the discovery and performed an area under the receiver operating characteristic curve (AUROC) analysis in the train, test, and external validation data.

RESULTS

The study data set included 299,468 (KYRBS; original data set) and 833 (KNHANES; external validation data set) patients with AR recruited between 2005 and 2022. The best-performing ML model was the random forest model with a mean AUROC of 84.12% (95% CI 83.98%-84.27%) in the original data set. Applying this result to the external validation data set revealed the best performance among the models, with an AUROC of 89.87% (sensitivity 83.33%, specificity 82.58%, accuracy 82.59%, and balanced accuracy 82.96%). While looking at feature importance, the 5 most important features in predicting suicide attempts in adolescent patients with AR are depression, stress status, academic achievement, age, and alcohol consumption.

CONCLUSIONS

This study emphasizes the potential of ML models in predicting suicide risks in patients with AR, encouraging further application of these models in other conditions to enhance adolescent health and decrease suicide rates.