Self-controlled Case Series Research Articles

Uptake, effectiveness and safety of COVID-19 vaccines in individuals at clinical risk due to immunosuppressive drug therapy or transplantation procedures: a population-based cohort study in England

BackgroundImmunocompromised individuals are at increased risk of severe COVID-19 outcomes, underscoring the importance of COVID-19 vaccination in this population. The lack of comprehensive real-world data on vaccine uptake, effectiveness and safety in these individuals presents a critical knowledge gap, highlighting the urgency to better understand and address the unique challenges faced by immunocompromised individuals in the context of COVID-19 vaccination.MethodsWe analysed data from 12,274,946 people in the UK aged > 12 years from 01/12/2020 to 11/04/2022. Of these, 583,541 (4.8%) were immunocompromised due to immunosuppressive drugs, organ transplants, dialysis or chemotherapy. We undertook a cohort analysis to determine COVID-19 vaccine uptake, nested case–control analyses adjusted for comorbidities and sociodemographic characteristics to determine effectiveness of vaccination against COVID-19 hospitalisation, ICU admission and death, and a self-controlled case series assessing vaccine safety for pre-specified adverse events of interest.ResultsOverall, 93.7% of immunocompromised individuals received at least one COVID-19 vaccine dose, with 80.4% having received three or more doses. Uptake reduced with increasing deprivation (hazard ratio [HR] 0.78 [95%CI 0.77–0.79] in the most deprived quintile compared to the least deprived quintile for the first dose). Estimated vaccine effectiveness against COVID-19 hospitalisation 2–6 weeks after the second and third doses compared to unvaccinated was 78% (95%CI 72–83) and 91% (95%CI 88–93) in the immunocompromised population, versus 85% (95%CI 83–86) and 86% (95%CI 85–89), respectively, for the general population. Results showed COVID-19 vaccines were protective against intensive care unit (ICU) admission and death in both populations, with effectiveness of over 92% against COVID-19-related death and up to 95% in reducing ICU admissions for both populations following the third dose. COVID-19 vaccines were generally safe for immunocompromised individuals, though specific doses of ChAdOx1, mRNA-1273 and BNT162b2 raised risks of specific cardiovascular/neurological conditions.ConclusionsCOVID-19 vaccine uptake is high in immunocompromised individuals on immunosuppressive drug therapy or who have undergone transplantation procedures, with documented disparities by deprivation. Findings suggest that COVID-19 vaccines are protective against severe COVID-19 outcomes in this vulnerable population, and show a similar safety profile in immunocompromised individuals and the general population, despite some increased risk of adverse events. These results underscore the importance of ongoing vaccination prioritisation for this clinically at-risk population to maximise protection against severe COVID-19 outcomes.

Association between influenza vaccination and one-year all-cause and cardiovascular mortality risk: A self-controlled case series and matched case-control study.

Debates surrounding the efficacy of influenza vaccination for survival benefits persist, and there is a lack of data regarding its duration of protection. A self-controlled case series (SCCS) and a 1:4 matched case-control study were conducted using the National Health Interview Survey (NHIS) and public-use mortality data from 2005 to 2018 in the United States. The SCCS study identified participants who received influenza vaccination within 12 months before the survey and subsequently died within 1 year of postvaccination. The matched case-control study paired participants who died during the influenza season at the time of survey with four survivors. Among 1167 participants in the SCCS study, there was a 46% reduction in all-cause mortality and a 43% reduction in cardiovascular mortality within 29-196 days of postvaccination. The greatest protection was observed during days 29-56 (all-cause mortality: RI: 0.19; 95% CI: 0.12-0.29; cardiovascular mortality: RI: 0.28; 95% CI: 0.14-0.56). Among 626 cases and 2504 controls included in the matched case-control study, influenza vaccination was associated with a reduction in all-cause mortality (OR: 0.74, 95% CI: 0.60-0.92) and cardiovascular mortality (OR: 0.64, 95% CI: 0.44-0.93) during the influenza season. This study highlights the importance of influenza vaccination in reducing the risks of all-cause and cardiovascular mortality, with effects lasting for approximately 6 months.

Herpes zoster vaccine and the risk of stroke: a population-based cohort study using linked data from the Clinical Practice Research Datalink

BackgroundStudies report herpes zoster associated with short-term stroke risk, but it is unclear whether herpes zoster vaccine reduces stroke risk.MethodsWe performed cohort studies using Clinical Practice Research Datalink Aurum linked...

Coronary and Cerebrovascular Events and Exacerbation of Existing Conditions After Laboratory‐Confirmed Influenza Infection Among US Veterans: A Self‐Controlled Case Series Study

ABSTRACTBackgroundInfluenza may contribute to coronary/cerebrovascular events and exacerbate underlying conditions.MethodsWe used self‐controlled case series (SCCS) design to analyze data from US Veterans ≥18 years with coronary/cerebrovascular or exacerbation event +/−1 year of lab‐confirmed influenza (LCI) during 2010–2018. We estimated the incidence ratio (IR) (95% CI) of the event for risk interval (Days 1–7 post‐LCI) versus control interval (all other times +/−1 year of LCI) with fixed‐effects conditional Poisson regression. We included biomarker data for mediation analysis.ResultsWe identified 3439 episodes with coronary/cerebrovascular‐related hospitalizations. IRs (95% CI) for LCI risk versus control interval were STEMI 0.6 (0.1, 4.4), NSTEMI 7.3 (5.8, 9.2), ischemic stroke 4.0 (3.0, 5.4), hemorrhagic stroke 6.2 (3.4, 11.5), and coronary spasm 1.3 (0.5, 3.0). IR significantly increased for NSTEMI and ischemic stroke among those ≥ 65 years. IR for NSTEMI and ischemic stroke dropped 26% and 10%, respectively, when white blood cell (WBC) and platelet count were considered. LCI was significantly associated with exacerbation of preexisting asthma, chronic obstructive pulmonary disease, and congestive heart failure.ConclusionsWe found significant association between LCI and hospitalization for NSTEMI, ischemic stroke, and hemorrhagic stroke, the latter possibly due to unaccounted time‐varying confounding in SCCS design.

Uptake, safety and effectiveness of inactivated influenza vaccine in inflammatory bowel disease: a UK-wide study

ObjectiveTo investigate (1) the UK-wide inactivated influenza vaccine (IIV) uptake in adults with inflammatory bowel disease (IBD), (2) the association between vaccination against influenza and IBD flare and (3) the...

Systemic Fluoroquinolone Use and Risk of Uveitis or Retinal Detachment

Fluoroquinolone use has been associated with increased risk of uveitis and retinal detachment in noninterventional studies, but the findings have been conflicting and causality is unclear. To estimate the association of systemic fluoroquinolone use with acute uveitis or retinal detachment, using multiple analyses and multiple databases to increase the robustness of results. This cohort study used data from the Clinical Practice Research Datalink Aurum and GOLD UK primary care records databases, which were linked to hospital admissions data. Adults prescribed a fluoroquinolone or a comparator antibiotic, cephalosporin, between April 1997 and December 2019 were included. Adults with uveitis or retinal detachment were analyzed in a separate self-controlled case series. Data analysis was performed from May 2022 to May 2023. Systemic fluoroquinolone or comparator antibiotic. The primary outcome was a diagnosis of acute uveitis or retinal detachment. Hazard ratios (HRs) were estimated in the cohort study for the association of fluoroquinolone prescription with either uveitis or retinal detachment, using stabilized inverse probability of treatment weighted Cox regression. Rate ratios (RRs) were estimated in the self-controlled case series, using conditional Poisson regression. Estimates were pooled across databases using fixed-effects meta-analysis. In total, 3 001 256 individuals in Aurum (1 893 561 women [63.1%]; median [IQR] age, 51 [35-68] years) and 434 754 in GOLD (276 259 women [63.5%]; median [IQR] age, 53 [37-70] years) were included in the cohort study. For uveitis, the pooled adjusted HRs (aHRs) for use of fluoroquinolone vs cephalosporin were 0.91 (95% CI, 0.72-1.14) at first treatment episode and 1.07 (95% CI, 0.92-1.25) over all treatment episodes. For retinal detachment, the pooled aHRs were 1.37 (95% CI, 0.80-2.36) at first treatment episode and 1.18 (95% CI, 0.84-1.65) over all treatment episodes. In the self-controlled case series, for uveitis, the pooled adjusted RRs (aRRs) for fluoroquinolone use vs nonuse were 1.13 (95% CI, 0.97-1.31) for 1 to 29 days of exposure, 1.16 (95% CI, 1.00-1.34) for 30 to 59 days, and 0.98 (95% CI, 0.74-1.31) for 60 days for longer. For retinal detachment, pooled aRRs for fluoroquinolone use vs nonuse were 1.15 (95% CI, 0.86-1.54) for 1 to 29 days of exposure, 0.94 (95% CI, 0.69-1.30) for 30 to 59 days, and 1.03 (95% CI, 0.59-1.78) for 60 days or longer. These findings do not support an association of systemic fluoroquinolone use with substantively increased risk of uveitis or retinal detachment. Although an association cannot be completely ruled out, these findings indicate that any absolute increase in risk would be small and, hence, of limited clinical importance.

COVID-19 vaccination safety and associated health care utilization among adults with inflammatory bowel disease – a population-based self-controlled case series analysis

Background and aimsThere is an incomplete understanding of the full safety profiles of repeated COVID-19 vaccinations in patients with inflammatory bowel disease (IBD). Among individuals with IBD, we assessed whether COVID-19 vaccines were associated with serious adverse events of special interest (AESI) and health care utilization [all-cause hospitalizations, Emergency Department (ED) visits, gastroenterology visits, IBD-related visits].MethodsUsing comprehensive administrative health data from Ontario, Canada, adults with IBD who received at least one COVID-19 vaccine from December 2020-January 2022 were included. Self-controlled case series analyses were conducted to evaluate the relative incidence rates of AESI and health care utilization outcomes across post-vaccination risk and control periods.ResultsAmong 88,407 IBD patients, 99.7% received mRNA vaccines and 75.9% received ≥ 3 doses. Relative to control periods, we did not detect an increase in AESI. IBD patients had fewer all-cause hospitalizations during post-vaccination risk periods. Patients experienced more all-cause ED visits after dose 2 [Relative Incidence (RI):1.08(95%CI:1.04–1.12)] but fewer visits after doses 3 [RI:0.85 (95%CI:0.81–0.90)] and 4 [RI:0.73 (95%CI:0.57–0.92)]. There was no increase in gastroenterologist visits or IBD-related health care utilization post-vaccination. There were fewer IBD-related hospitalizations after dose 1 [RI:0.84 (95%CI:0.72–0.98)] and 3 [RI:0.63 (95%CI:0.52–0.76)], fewer IBD-related ED visits after dose 3 [RI:0.81 (95%CI:0.71–0.91)] and 4 [RI:0.55 (95%CI:0.32–0.96)], and fewer outpatient visits after dose 2 [RI:0.91 (95%CI:0.90–0.93)] and 3 [RI:0.87 (95%CI:0.86–0.89)].ConclusionThis population-based study did not detect increased AESI, all-cause or IBD-related health care utilization following COVID-19 vaccination, suggesting a lack of association between vaccination and increased disease activity.

Safety outcomes following COVID-19 vaccination and infection in 5.1 million children in England

The risk-benefit profile of COVID-19 vaccination in children remains uncertain. A self-controlled case-series study was conducted using linked data of 5.1 million children in England to compare risks of hospitalisation from vaccine safety outcomes after COVID-19 vaccination and infection. In 5-11-year-olds, we found no increased risks of adverse events 1–42 days following vaccination with BNT162b2, mRNA-1273 or ChAdOX1. In 12-17-year-olds, we estimated 3 (95%CI 0–5) and 5 (95%CI 3–6) additional cases of myocarditis per million following a first and second dose with BNT162b2, respectively. An additional 12 (95%CI 0–23) hospitalisations with epilepsy and 4 (95%CI 0–6) with demyelinating disease (in females only, mainly optic neuritis) were estimated per million following a second dose with BNT162b2. SARS-CoV-2 infection was associated with increased risks of hospitalisation from seven outcomes including multisystem inflammatory syndrome and myocarditis, but these risks were largely absent in those vaccinated prior to infection. We report a favourable safety profile of COVID-19 vaccination in under-18s.

Autologous PRP therapy for thin endometrium: A self-controlled case series study across menstrual cycles

ObjectivesThin endometrium (TE) compromises endometrial receptivity, often leading to implantation failure and lower clinical pregnancy rates. As autologous platelet-rich plasma (PRP) emerges as a potential remedy, the present study focused on its therapeutic effects on TE in infertile women who underwent frozen embryo transfer. Study designPatients with TE who underwent frozen embryo transfer treatment in our hospital were included. To diminish individual variability, a self-controlled series approach was used. Two menstrual study cycles were arranged for each participant before the actual embryo transfer cycle; PRP treatment was conducted in the second cycle. Key metrics analyzed included endometrial thickness and the expression of specific endometrial biomarkers including HOXA-10, Ki67, and αvβ3 integrin. Transvaginal ultrasound was employed to measure endometrial thickness on Days 11 and 14, and an endometrial biopsy was conducted on progesterone Day 5 of the first two cycles. Pregnancy outcomes were observed after the embryo transfer cycle. ResultsPRP treatment significantly increased the median endometrial thickness, from 5.8 mm to 6.5 mm (P = 0.0066). Additionally, PRP treatment resulted in a statistically significant increase in the H-score for all endometrial markers. Importantly, during the subsequent embryo transfer cycle with PRP treatment, two patients successfully achieved pregnancies, both culminating in live births. ConclusionsThese findings emphasize the potential of PRP in improving endometrial conditions, especially for individuals grappling with thin endometrium issues, as underscored by this self-comparison methodology.

Unveiling unique clinical phenotypes of hip fracture patients and the temporal association with cardiovascular events

Cardiovascular events are the leading cause of death among hip fracture patients. This study aims to identify subphenotypes of hip fracture patients and investigate their association with incident cardiovascular events, all-cause mortality, and health service utilisation in Hong Kong and the United Kingdom populations. By the latent class analysis, we show three distinct clusters in the Hong Kong cohort (n = 78,417): Cluster 1 has cerebrovascular and hypertensive diseases, hyperlipidemia, and diabetes; Cluster 2 has congestive heart failure; Cluster 3 consists of relatively healthy patients. Compared to Cluster 3, higher risks of major adverse cardiovascular events are observed in Cluster 1 (hazard ratio 1.97, 95% CI 1.83 to 2.12) and Cluster 2 (hazard ratio 4.06, 95% CI 3.78 to 4.35). Clusters 1 and 2 are also associated with a higher risk of mortality, more unplanned accident and emergency visits and longer hospital stays. Self-controlled case series analysis shows a significantly elevated risk of major adverse cardiovascular events within 60 days post-hip fracture. Similar associations are observed in the United Kingdom cohort (n = 27,948). Pre-existing heart failure is identified as a unique subphenotype associated with poor prognosis after hip fractures.

Importance of Examining Incidentality in Vaccine Safety Assessment

The author believes that the principles of statistical methods for vaccine safety can be divided into three categories: comparison of adverse event incidence rates between vaccinated and unvaccinated groups, analysis of incidentality in the vaccinated group, and a combination of both. The first category includes the cohort study; the second, the self-controlled risk interval design (SCRI); and the third, the self-controlled case series method. A single p-value alone should not determine a scientific conclusion, and analysis should be performed using multiple statistical methods with different principles. The author believes that using both the cohort study and the SCRI for analysis is the best method to assess vaccine safety. When the cohort study may not detect a significant difference owing to a low incidence rate of an adverse event in the vaccinated group or a high one in the unvaccinated group, the SCRI may detect it. Because vaccines must have a higher level of safety than the pharmaceuticals used for treatment, vaccine safety is advisable to be assessed using methods that can detect a significant difference even for any value of the incidence rate of an adverse event. The author believes that the analyses of COVID-19 vaccine safety have areas for improvement because the proportion of papers that used the cohort study and the SCRI was negligible.

Assessment of potential adverse events following the 2022–2023 seasonal influenza vaccines among U.S. adults aged 65 years and older

BackgroundWhile safety of influenza vaccines is well-established, some studies have suggested potential associations between influenza vaccines and certain adverse events (AEs). This study examined the safety of the 2022–2023 influenza vaccines among U.S. adults ≥ 65 years. MethodsA self-controlled case series compared incidence rates of anaphylaxis, encephalitis/encephalomyelitis, Guillain-Barré Syndrome (GBS), and transverse myelitis following 2022–2023 seasonal influenza vaccinations (i.e., any, high-dose or adjuvanted) in risk and control intervals among Medicare beneficiaries ≥ 65 years. We used conditional Poisson regression to estimate incidence rate ratios (IRRs) and 95 % confidence intervals (CIs) adjusted for event-dependent observation time and seasonality. Analyses also accounted for uncertainty from outcome misclassification where feasible. For AEs with any statistically significant associations, we stratified results by concomitant vaccination status. ResultsAmong 12.7 million vaccine recipients, we observed 76 anaphylaxis, 276 encephalitis/encephalomyelitis, 134 GBS and 75 transverse myelitis cases. Only rates of anaphylaxis were elevated in risk compared to control intervals. With all adjustments, an elevated, but non-statistically significant, anaphylaxis rate was observed following any (IRR: 2.40, 95% CI: 0.96–6.03), high-dose (IRR: 2.31, 95% CI: 0.67–7.91), and adjuvanted (IRR: 3.28, 95% CI: 0.71–15.08) influenza vaccination; anaphylaxis IRRs were 2.54 (95% CI: 0.49–13.05) and 1.64 (95% CI: 0.38–7.05) for persons with and without concomitant vaccination, respectively. ConclusionsRates of encephalitis/encephalomyelitis, GBS, or transverse myelitis were not elevated following 2022–2023 seasonal influenza vaccinations among U.S. adults ≥ 65 years. There was an increased rate of anaphylaxis following influenza vaccination that may have been influenced by concomitant vaccination.

Triptan use in elderly over 65 years and the risk of hospitalization for serious vascular events

BackgroundSeveral studies have focused on the use of triptan and the risk of acute vascular events but the existence of such association is still debated and has never been quantified in patients over 65 years. To assess whether triptan use among older is associated with an increased risk of hospitalization for acute vascular events.MethodsA propensity score-matched cohort study was designed using the French national health insurance database linked to hospital stays. Patients aged ≥ 65 years, newly treated by triptans between 2011 and 2014, were included… The primary event was hospitalization for an acute ischemic vascular event within de 90 days following triptan initiation. Association with triptan exposure was investigated through cox regression model, considering exposure at inclusion, and with exposure as a time-varying variable A case-crossover (CCO) and a self-controlled case series (SCCS) analyses were also conducted to address potential residual confounding.ResultsThe cohort included 24, 774 triptan users and 99 096 propensity matched controls (mean (SD) age: 71 years (5.9), 74% of women). Within 90 days after cohort entry, 163 events were observed in the triptan group, and 523 in the control group (0.66% vs. 0.53%, adjusted hazard ratio (aHR) exposed/not exposed 1.25 95%CI [1.05–1.49]; aHR time−varying 8.74 [5.21–14.66]). The association was significant (CCO) for all events (adjusted odds ratio (aOR1.63 [1.22–2.19]) with a more consistent association with cerebral events (aOR 2.14 [1.26–3.63]). The relative incidence (RI) for all events was 2.13 [1.76–2.58] in the SCCS, for cardiac (RI: 1.67 [1.23–2.27]) and for cerebral events (RI: 3.20, [2.30–4.45]).ConclusionThe incidence of acute vascular events was low among triptan users. We found that triptan use among older may be associated with a low increased risk for acute vascular events, which may be more marked for cerebral events such as stroke, than for cardiac events.

Pfizer COVID19 vaccine is not associated with acute cardiovascular events excluding myocarditis– a national self-controlled case series study

BackgroundDespite publications assuring no increased risk for acute cardiovascular events (excluding myocarditis) and sudden death following administration of COVID19 vaccines, these issues still stir much public ado. We assessed the risk for acute cardiovascular events that require hospitalization (excluding myocarditis) and for mortality in the short-term following administration of the second dose of the Pfizer COVID19 vaccine in Israel.MethodsUsing a self-controlled case series (SCCS) study design and national databases, all second-dose vaccinees, who had not been diagnosed with COVID19 and who had an acute cardiovascular event (acute myocardial infarction/acute stroke/acute thromboembolic event) that required hospitalization in the 60 days following vaccine administration between Jan 11th, 2021 and Oct 31st 2021, were included. A similar analysis was carried out for mortality. The first 30 days following vaccination were defined as risk period while the next 30 days were defined as control period. The probability for an event between these periods was compared using a conditional logistic regression model, accounting for sex, age group, background morbidity and seasonal risk.ResultsOut of 5,700,112 second dose vaccinees, 4,163 had an acute cardiovascular event in the 60 days following vaccine administration. Following exclusion of 106 due to technical considerations, 1,979 events occurred during the risk period and 2,078 during the control period: Odds ratio, OR = 0.95, 95% confidence interval, CI 0.90–1.01, p = 0.12. Adjusted OR was similar (OR = 0.88, 95%CI 0.72–1.08). Stratifying by age showed no increased risk in any age group. Mortality assessment indicated low number of events in both periods. These results were consistent in sensitivity analyses.ConclusionsThere was no increased risk for acute cardiovascular events (excluding myocarditis) in the risk period compared to the control period following administration of the second dose of Pfizer COVID19 vaccine. Mortality data raised no concerns either, but may have been biased.

P021 Uptake, safety, and effectiveness of pneumococcal vaccination in adults with immune mediated inflammatory diseases: a UK wide study using data from the Clinical Practice Research Datalink

Abstract Background/Aims The safety and effectiveness of pneumococcal vaccine in people with immune mediated inflammatory diseases (IMIDs) is not known, which may contribute to suboptimal uptake. We investigated UK wide pneumococcal vaccine uptake in adults with IMIDs, the association between pneumococcal vaccination and disease flares, and the effectiveness of pneumococcal vaccine in preventing pneumonia in this at-risk population. Methods Adults with incident rheumatoid arthritis (RA), inflammatory bowel disease (IBD), systemic lupus erythematosus (SLE) and spondyloarthritis (SpA) prior to 31st August 2018 in the Clinical Practice Research Datalink (CPRD) Gold were included. The study was approved by CPRD research data governance (Reference 21_000614). We calculated the proportion of patients vaccinated against pneumococcal pneumonia. To investigate the association between vaccination and IMID flare, we employed a self-controlled case series analysis, adjusted for season. The study period was up-to six-month before and six-month after the date of pneumococcal vaccination. This period was partitioned into induction (14 days pre-vaccination) and exposed periods (up-to 90 days post vaccination) with the remaining time considered unexposed. Incidence rate ratios (IRR) and 95% CI were calculated. We conducted a multivariable nested case-control study to assess vaccine effectiveness. Cases were patients hospitalised with pneumonia and were matched to up to ten controls for age and sex. Multivariable conditional logistic regression was used to calculate odds ratio (OR) and 95% CI. Results We included 32,277 IMID patients: 14,151 with RA, 13,631 with IBD, 3,804 with SpA and 691 with SLE. Overall uptake of pneumococcal vaccination was 50% (95% CI 49.4% -50.5%). Vaccination uptake was significantly lower in the under 45-year-olds, in patients with IBD and in those without additional indication for vaccination at 29.7%, 38.4%, 42.7% respectively. In the safety study, data for 1001, 854, 424 vaccinated patients with primary care consultations for joint pain, AIRD flare, and IBD flare respectively were included. Vaccination against pneumococcal pneumonia was not associated with AIRD flare (IRR (95% CI) 1.07 (0.93-1.22)), primary care consultations for joint pain (IRR (95% CI) 0.95 (0.83-1.10)), and IBD flare (IRR (95% CI) 0.82 (0.64-1.06)) in the 90-days post vaccination. The vaccine effectiveness study included 25,707 patients, either with (n = 2,771) or without (n = 22,936) a hospitalisation record for pneumonia after IMID diagnosis. Patients hospitalised for pneumonia compared with their matched controls, had higher odds of current smoking, deprivation, corticosteroid prescriptions, additional indication for vaccination, primary care consultations, hospital admissions and prescriptions. In the multivariable adjusted model, pneumococcal vaccination was associated with reduced odds of hospitalisation for pneumonia (OR (95% CI) 0.88 (0.78-0.98). Conclusion The uptake of pneumococcal vaccine is low in IMID patients. Pneumococcal vaccination is not associated with IMID flare and is protective against pneumonia. These findings call for promotion of pneumococcal vaccination in IMID by health professionals. Disclosure G. Nakafero: None. M.J. Grainge: None. C.D. Mallen: Grants/research support; NIHR, MRC, Versus Arthritis and BMS. T. Card: None. J.S. Nguyen Van-Tam: Consultancies; CSL Seqirus and Moderna. Royalties; AstraZeneca and Sanofi Pasteur. A. Abhishek: Consultancies; NGM Bio, Limbic and Inflazome.. Royalties; UpToDate, Springer, Cadilla Pharmaceuticals.. Grants/research support; AstraZeneca and Oxford Immunotech..

Antibiotic Prophylaxis and Infective Endocarditis Incidence Following Invasive Dental Procedures

The association between antibiotic prophylaxis and infective endocarditis after invasive dental procedures is still unclear. Indications for antibiotic prophylaxis were restricted by guidelines beginning in 2007. To systematically review and analyze existing evidence on the association between antibiotic prophylaxis and infective endocarditis following invasive dental procedures. PubMed, Cochrane-CENTRAL, Scopus, Web of Science, Proquest, Embase, Dentistry and Oral Sciences Source, and ClinicalTrials.gov were systematically searched from inception to May 2023. Studies on the association between antibiotic prophylaxis and infective endocarditis following invasive dental procedures or time-trend analyses of infective endocarditis incidence before and after current antibiotic prophylaxis guidelines were included. Study quality was evaluated using structured tools. Data were extracted by independent observers. A pooled relative risk (RR) of developing infective endocarditis following invasive dental procedures in individuals who were receiving antibiotic prophylaxis vs those who were not was computed by random-effects meta-analysis. The outcome of interest was the incidence of infective endocarditis following invasive dental procedures in relation to antibiotic prophylaxis. Of 11 217 records identified, 30 were included (1 152 345 infective endocarditis cases). Of them, 8 (including 12 substudies) were either case-control/crossover or cohort studies or self-controlled case series, while 22 were time-trend studies; all were of good quality. Eight of the 12 substudies with case-control/crossover, cohort, or self-controlled case series designs performed a formal statistical analysis; 5 supported a protective role of antibiotic prophylaxis, especially among individuals at high risk, while 3 did not. By meta-analysis, antibiotic prophylaxis was associated with a significantly lower risk of infective endocarditis after invasive dental procedures in individuals at high risk (pooled RR, 0.41; 95% CI, 0.29-0.57; P for heterogeneity = .51; I2, 0%). Nineteen of the 22 time-trend studies performed a formal pre-post statistical analysis; 9 found no significant changes in infective endocarditis incidence, 7 demonstrated a significant increase for the overall population or subpopulations (individuals at high and moderate risk, streptococcus-infective endocarditis, and viridans group streptococci-infective endocarditis), whereas 3 found a significant decrease for the overall population and among oral streptococcus-infective endocarditis. While results from time-trend studies were inconsistent, data from case-control/crossover, cohort, and self-controlled case series studies showed that use of antibiotic prophylaxis is associated with reduced risk of infective endocarditis following invasive dental procedures in individuals at high risk, while no association was proven for those at low/unknown risk, thereby supporting current American Heart Association and European Society of Cardiology recommendations. Currently, there is insufficient data to support any benefit of antibiotic prophylaxis in individuals at moderate risk.

Evaluating the risk of conflict on recent Ebola outbreaks in Guinea and the Democratic Republic of the Congo.

Reducing Ebola virus transmission relies on the ability to identify cases and limit contact with infected bodily fluids through biosecurity, safe sex practices, safe burial and vaccination. Armed conflicts can complicate outbreak detection and interventions due to widespread disruption to governments and populations. Guinea and the Democratic Republic of the Congo (DRC) have historically reported the largest and the most recent Ebola virus outbreaks. Understanding if conflict played a role in these outbreaks may help in identifying key risks factors to improve disease control. We used data from a range of publicly available data sources for both Ebola virus cases and conflict events from 2018 to 2021 in Guinea and the DRC. We fitted these data to conditional logistic regression models using the Self-Controlled Case Series methodology to evaluate the magnitude in which conflict increased the risk of reported Ebola virus cases in terms of incidence rate ratio. We re-ran the analysis sub-nationally, by conflict sub-event type and tested any lagged effects. Conflict was significantly associated with an increased risk of reported Ebola virus cases in both the DRC and Guinea in recent outbreaks. The effect was of a similar magnitude at 1.88- and 1.98-times increased risk for the DRC and Guinea, respectively. The greatest effects (often higher than the national values) were found in many conflict prone areas and during protest/riot-related conflict events. Conflict was influential in terms of Ebola virus risk from 1week following the event and remained important by 10weeks. Extra vigilance is needed following protests and riot-related conflict events in terms of Ebola virus transmission. These events are highly disruptive, in terms of access to transportation and healthcare and are often in urban areas with high population densities. Additional public health messaging around these types of conflict events, relating to the risks and clinical symptoms may be helpful in reducing transmission. Future work should aim to further understand and quantify conflict severity and intensity, to evaluate dose-response relationships in terms of disease risk.

Stroke Risk After COVID-19 Bivalent Vaccination Among US Older Adults

In January 2023, the US Centers for Disease Control and Prevention and the US Food and Drug Administration noted a safety concern for ischemic stroke among adults aged 65 years or older who received the Pfizer-BioNTech BNT162b2; WT/OMI BA.4/BA.5 COVID-19 bivalent vaccine. To evaluate stroke risk after administration of (1) either brand of the COVID-19 bivalent vaccine, (2) either brand of the COVID-19 bivalent plus a high-dose or adjuvanted influenza vaccine on the same day (concomitant administration), and (3) a high-dose or adjuvanted influenza vaccine. Self-controlled case series including 11 001 Medicare beneficiaries aged 65 years or older who experienced stroke after receiving either brand of the COVID-19 bivalent vaccine (among 5 397 278 vaccinated individuals). The study period was August 31, 2022, through February 4, 2023. Receipt of (1) either brand of the COVID-19 bivalent vaccine (primary) or (2) a high-dose or adjuvanted influenza vaccine (secondary). Stroke risk (nonhemorrhagic stroke, transient ischemic attack, combined outcome of nonhemorrhagic stroke or transient ischemic attack, or hemorrhagic stroke) during the 1- to 21-day or 22- to 42-day risk window after vaccination vs the 43- to 90-day control window. There were 5 397 278 Medicare beneficiaries who received either brand of the COVID-19 bivalent vaccine (median age, 74 years [IQR, 70-80 years]; 56% were women). Among the 11 001 beneficiaries who experienced stroke after receiving either brand of the COVID-19 bivalent vaccine, there were no statistically significant associations between either brand of the COVID-19 bivalent vaccine and the outcomes of nonhemorrhagic stroke, transient ischemic attack, nonhemorrhagic stroke or transient ischemic attack, or hemorrhagic stroke during the 1- to 21-day or 22- to 42-day risk window vs the 43- to 90-day control window (incidence rate ratio [IRR] range, 0.72-1.12). Among the 4596 beneficiaries who experienced stroke after concomitant administration of either brand of the COVID-19 bivalent vaccine plus a high-dose or adjuvanted influenza vaccine, there was a statistically significant association between vaccination and nonhemorrhagic stroke during the 22- to 42-day risk window for the Pfizer-BioNTech BNT162b2; WT/OMI BA.4/BA.5 COVID-19 bivalent vaccine (IRR, 1.20 [95% CI, 1.01-1.42]; risk difference/100 000 doses, 3.13 [95% CI, 0.05-6.22]) and a statistically significant association between vaccination and transient ischemic attack during the 1- to 21-day risk window for the Moderna mRNA-1273.222 COVID-19 bivalent vaccine (IRR, 1.35 [95% CI, 1.06-1.74]; risk difference/100 000 doses, 3.33 [95% CI, 0.46-6.20]). Among the 21 345 beneficiaries who experienced stroke after administration of a high-dose or adjuvanted influenza vaccine, there was a statistically significant association between vaccination and nonhemorrhagic stroke during the 22- to 42-day risk window (IRR, 1.09 [95% CI, 1.02-1.17]; risk difference/100 000 doses, 1.65 [95% CI, 0.43-2.87]). Among Medicare beneficiaries aged 65 years or older who experienced stroke after receiving either brand of the COVID-19 bivalent vaccine, there was no evidence of a significantly elevated risk for stroke during the days immediately after vaccination.

Risk of encephalitis and meningitis after COVID-19 vaccination in South Korea: a self-controlled case series analysis

BackgroundSeveral neurological manifestations shortly after a receipt of coronavirus infectious disease 2019 (COVID-19) vaccine have been described in the recent case reports. Among those, we sought to evaluate the risk of encephalitis and meningitis after COVID-19 vaccination in the entire South Korean population.MethodsWe conducted self-controlled case series (SCCS) analysis using the COVID-19 immunization record data from the Korea Disease Control Agency between February 2021 and March 2022, linked with the National Health Insurance Database between January 2021 and October 2022. We retrieved all medical claims of adults aged 18 years or older who received at least one dose of COVID-19 vaccines (BNT162b2, mRNA-1273, ChAdOx1-S, or Ad26.COV2.S), and included only those who had a diagnosis record for encephalitis or meningitis within the 240-day post-vaccination period. With day 0 defined as the date of vaccination, risk window was defined as days 1–28 and the control window as the remainder period excluding the risk windows within the 240-day period. We used conditional Poisson regression to estimate the incidence rate ratios (IRR) with 95% confidence intervals (CI), stratified by dose and vaccine type.ResultsFrom 129,956,027 COVID-19 vaccine doses administered to 44,564,345 individuals, there were 251 and 398 cases of encephalitis and meningitis during the risk window, corresponding to 1.9 and 3.1 cases per 1 million doses, respectively. Overall, there was an increased risk of encephalitis in the first 28 days of COVID-19 vaccination (IRR 1.26; 95% CI 1.08–1.47), which was only significant after a receipt of ChAdOx1-S (1.49; 1.03–2.15). For meningitis, no increased risk was observed after any dose of COVID-19 vaccine (IRR 1.03; 95% CI 0.91–1.16).ConclusionsOur findings suggest an overall increased risk of encephalitis after COVID-19 vaccination. However, the absolute risk was small and should not impede COVID-19 vaccine confidence. No significant association was found between the risk of meningitis and COVID-19 vaccination.

Uptake and safety of pneumococcal vaccination in adults with immune mediated inflammatory diseases: a UK wide observational study.

The uptake and safety of pneumococcal vaccination in people with immune mediated inflammatory diseases (IMIDs) is poorly understood. We investigated the UK wide pneumococcal vaccine uptake in adults with IMIDs and explored the association between vaccination and IMID flare. Adults with IMIDs diagnosed on or before 01/09/2018, prescribed steroid-sparing drugs within the last 12 months and contributing data to the Clinical Practice Research Datalink Gold were included. Vaccine uptake was assessed using a cross-sectional study design. Self-controlled case series (SCCS) analysis investigated the association between pneumococcal vaccination and IMID flare. The SCCS observation period was up-to six-month before and after pneumococcal vaccination. This was partitioned into a 14-day pre-vaccination induction, 90-days post-vaccination exposed, and the remaining unexposed periods. We included 32 277 patients, 14 151 with RA, 13 631 with IBD, 3,804 with axial spondyloarthritis and 691 with SLE. Overall, 57% were vaccinated against pneumococcus. Vaccine uptake was lower in those younger than 45 years (32%), with IBD (42%), and without additional indication(s) for vaccination (46%). In the vaccine-safety study, data for 1,067, 935, and 451vaccinated patients with primary-care consultations for joint pain, AIRD flare and IBD flare respectively were included. Vaccination against pneumococcal pneumonia was not associated with primary-care consultations for joint pain, AIRD flare and IBD flare in the exposed period with incidence rate ratios (95% Confidence Interval) 0.95 (0.83-1.09), 1.05 (0.92-1.19), and 0.83 (0.65-1.06) respectively. Uptake of pneumococcal vaccination in UK patients with IMIDs was suboptimal. Vaccination against pneumococcal disease was not associated with IMID flare.