Influence of influenza vaccination on recurrent hospitalization in patients with heart failure

Influenza Vaccination and Cardiovascular Outcomes in Patients with Coronary Artery Diseases: A Placebo-Controlled Randomized Study, IVCAD

Background/Objectives: Influenza infection is associated with cardiovascular morbidity and mortality; however, the effect of influenza vaccination on cardiovascular outcomes is not fully understood. This clinical trial aimed to investigate the correlation between cardiovascular outcomes and influenza vaccine (FluVac) in coronary artery disease (CAD) subjects. Methods: This was a randomized single-blinded placebo-controlled trial. Enrolled CAD subjects received 0.5 mL of 2007-2008 trivalent FluVac (15 µg hemagglutinin of each of Solomon Islands/3/2006 (H1N1), Wisconsin/67/2005 (H3N2), and Malaysia/2506/2004 (B)). The subjects were followed up at 1 month (hemagglutinin (HA) antibody titers) and at 12 months post-vaccination for evaluation of outcomes (influenza-like episodes, acute coronary syndrome (ACS), myocardial infarction (MI), coronary revascularization, and death). Results: In total, 278 eligible CAD subjects were randomized to receive either FluVac (n = 137) or a placebo (n = 141), of which consequently 131 and 135 subjects completed the study. Cardiovascular deaths (3/131 [2.29%] vs. 3/135 [2.22%]) and all-cause deaths (4/131 [3.05%] vs. 4/135 [2.96%]) were similar in both groups. Adverse cardiovascular events, including ACS, MI, and coronary revascularization, were less frequent in the vaccine group but did not reach statistical significance. The magnitude of the antibody change and serologic response (≥4-fold HI titer rise) of all three antibodies were significantly higher in the vaccine group compared to the placebo but did not correlate with cardiovascular outcomes in the FluVac group. Conclusions: The influenza vaccine may improve cardiovascular outcomes, though this improvement is not correlated with post-vaccination antibody titers. Despite the controversy, influenza vaccination is recommended in the CAD population (clinicaltrials.gov; NCT00607178).

Pneumococcal and Influenza Vaccination Coverage in Patients with Heart Failure: A Systematic Review

Background/Objectives: As heart failure (HF) patients face increased vulnerability to respiratory infections, optimizing pneumococcal and influenza vaccination coverage becomes pivotal for mitigating additional health risks and reducing hospitalizations, morbidity, and mortality rates within this population. In this specific subpopulation of patients, vaccination coverage for pneumococcal and influenza holds heightened significance compared to other vaccines due to their susceptibility to respiratory infections, which can exacerbate existing cardiovascular conditions and lead to severe complications or even death. However, despite the recognized benefits, vaccination coverage among HF patients remains below expectations. The aim of the present systematic review was to assess the vaccination coverage for influenza and pneumococcus in HF patients from 2005 to 2023 and the vaccination's effects on survival and hospitalizations. Methods: The authors developed the protocol of the review in accordance with the PRISMA guidelines, and the search was performed in databases including PubMed and Scopus. After the initial search, 851 studies were found in PubMed Library and 1961 in Scopus (total of 2812 studies). Results: After the initial evaluation, 23 publications were finally included in the analysis. The total study population consisted of 6,093,497 participants. Regarding the influenza vaccine, vaccination coverage ranged from low rates of 2.5% to very high rates of 97%, while the respective pneumococcal vaccination coverage ranged from 20% to 84.6%. Most studies demonstrated a beneficial effect of vaccination on survival and hospitalizations. Conclusions: The present systematic review study showed a wide variety of vaccination coverage among patients with heart failure.

Vaccines and cardiovascular outcomes: lessons learned from influenza epidemics

Cardiovascular disease (CVD) is the leading cause of death in the world and is largely preventable. An increasing amount of evidence suggests that annual influenza vaccination reduces CVD-related morbidity and mortality. Despite various clinical guidelines recommending annual influenza vaccination for the general population for influenza-like illness risk reduction, with a particular emphasis on people with CVD, vaccination rates fall consistently below the goal established by the World Health Organization. This review outlines the importance of influenza vaccination, mechanisms of cardiovascular events in influenza, summarizing the available literature on the effects of influenza vaccine in CVD and the benefits of influenza vaccine during the COVID-19 pandemic.

The need for vaccination in adults with chronic (noncommunicable) diseases in India - lessons from around the world

Worldwide, chronic diseases (noncommunicable diseases [NCDs]) cause 41 million (71%) deaths annually. They are the leading cause of mortality in India, contributing to 60% of total deaths each year. Individuals with these diseases are more susceptible to vaccine-preventable diseases (VPDs) and have an increased risk of associated disease severity and complications. This poses a substantial burden on healthcare systems and economies, exemplified by the COVID-19 pandemic. Vaccines are an effective strategy to combat these challenges; however, utilization rates are inadequate. With India running one of the world’s largest COVID-19 vaccination programs, this presents an opportunity to improve vaccination coverage for all VPDs. Here we discuss the burden of VPDs in those with NCDs, the benefit of vaccinations, current challenges and possible strategies that may facilitate implementation and accessibility of vaccination programs. Effective vaccination will have a significant impact on the disease burden of both VPDs and NCDs and beyond.

What is already known on this topic?

Annually, chronic or noncommunicable diseases (NCDs) cause >40 million deaths worldwide and 60% of all deaths in India

Adults with these diseases are more susceptible to vaccine-preventable diseases (VPDs); however, vaccine utilization is inadequate in this population

What is added by this report?

We highlight the benefits of vaccination in adults with NCDs that extend beyond disease prevention

We discuss key challenges in implementing adult vaccination programs and provide practical solutions

What are the implications for public health practice?

Raising awareness about the benefits of vaccinations, particularly for those with NCDs, and providing national guidelines with recommendations from medical societies, will increase vaccine acceptance

Adequate vaccine acceptance will reduce the VPD burden in this vulnerable population

Influenza vaccination and mortality among adults with heart failure in an integrated healthcare delivery system, 2009-2018

BACKGROUND

Influenza infection can result in decompensation or exacerbation of heart failure (HF) symptoms, hospitalization, and death.

OBJECTIVE

To examine the association of influenza vaccination with mortality and hospitalization during influenza and non-influenza seasons between 2009 and 2018.

DESIGN, SETTING, AND PARTICIPANTS

In this prospective, observational cohort study, we included Kaiser Permanente Southern California members with a HF diagnosis prior to September 1 each year from 2009 to 2017.

EXPOSURE

The first influenza vaccination in each season (September 1 to May 31) was recorded. Vaccinated/unvaccinated patients were matched 1:1 on age, sex, and ejection fraction at the vaccination date (n-total = 74,870).

MAIN OUTCOMES

Patients were followed through the end of each influenza season for all-cause mortality. Secondary outcomes included cardiovascular mortality and all-cause hospitalization. In a sensitivity analysis, we examined mortality in the non-influenza season.

RESULTS

Influenza vaccinated vs unvaccinated patients had more comorbidities and higher healthcare utilization. After multivariable adjustment for utilization, sociodemographics, comorbidities, and medications, influenza vaccinated vs unvaccinated patients had a lower risk of all-cause mortality and cardiovascular mortality during the influenza season (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.63, 0.70 and HR 0.68, 95% CI 0.63, 0.74, respectively) but a higher risk of all-cause hospitalization (HR 1.27, 95% CI 1.21, 1.31). There was no association between influenza vaccination and all-cause or cardiovascular mortality during the non-influenza season (HR 0.99, 95% CI 0.89, 1.09 and HR 1.00, 95% CI 0.84, 1.21, respectively).

CONCLUSIONS

Influenza vaccination in HF patients was associated with a lower risk of mortality during the influenza season. Our findings provide support for recommendations of universal influenza vaccination in patients with HF.

Cardioprotective effects of Influenza Vaccination among Patients with Established Cardiovascular Disease or at High Cardiovascular Risk: A Systematic Review and Meta-analysis

BACKGROUND

The clinical impact of the influenza vaccination on cardiovascular outcomes in people with established cardiovascular disease (CVD) is still debated.

AIM

The aim of this meta-analysis was to estimate the effect of influenza vaccination on cardiovascular and cerebrovascular outcomes among patients with established CVD.

METHODS

We systematically searched all electronic databases from inception until 15 April 2022. Primary clinical outcomes were all-cause mortality (ACM), and major adverse clinical events (MACE). Secondary endpoints were heart failure, myocardial infarction, CV mortality, and stroke.

RESULTS

Eighteen articles (five randomized trials and thirteen observational studies), with a total of 22,532,165 patients were included in the analysis. There were 217,072 participants included in the high cardiovascular risk or established CVD population (vaccinated n = 111,073 and unvaccinated n = 105,999). The mean age of the patients was 68 years old, without any difference between groups (69 vs 71) years. At mean follow-up of 1.5 years, vaccinated group was associated with lower risk for all-cause mortality [HR, 0.71(95%CI, 0.63-0.80), p < 0.001], MACE [HR, 0.83(95%CI:0.72-0.96), p = 0.01], CV mortality [HR, 0.78(95%CI:0.68-0.90), p < 0.001] and myocardial infarction [HR, 0.82(95%CI:0.74-0.92), p < 0.001] compared to unvaccinated group. While incidence of stroke [HR, 1.03 (95%CI, 0.92-1.06), p = 0.61] and heart failure [HR, 0.74 (95%CI, 0.51-1.08), p = 0.12] did not differ between the two groups.

CONCLUSION

Influenza vaccination reduced major adverse clinical events, all-cause mortality, CV mortality and myocardial infarction. These highlighted the importance of influenza vaccination in established CVD or high cardiovascular risk.

Effectiveness of the influenza vaccine at reducing adverse events in patients with heart failure: A systematic review and meta-analysis

BACKGROUND

The association between influenza and adverse vascular events in patients with heart failure is well documented. The effect of the influenza vaccine on preventing such adverse events is uncertain. This systematic review and meta-analysis addressed whether vaccination against influenza reduces adverse vascular events and mortality in heart failure patients.

METHODS

MEDLINE and EMBASE databases were comprehensively searched, study screening and quality assessment were completed, and data was synthesized. Eligible studies investigated heart failure patients who received the influenza vaccine, and reported outcomes within 12 months, compared to heart failure patients who did not receive the influenza vaccine. The following 6 outcomes were assessed: all-cause mortality, cardiovascular-related mortality, all-cause hospitalization, cardiovascular-related hospitalization, non-fatal myocardial infarction, and non-fatal stroke. Risk of bias was assessed using the Newcastle-Ottawa Scale and a GRADE assessment was completed. A random-effects meta-analysis was performed to estimate the pooled risk ratio (RR), 95% confidence intervals (CIs), and heterogeneity using I² statistics.

RESULTS

After synthesizing data from 7 non-randomized studies (247,842 patients), the results demonstrate the risk of all-cause mortality is significantly reduced within 12 months of a heart failure patient receiving the influenza vaccine (RR = 0.75, 95% CI 0.71-0.79; P<0.0001); very low certainty of evidence. The risk of cardiovascular-related mortality was significantly reduced (RR = 0.77, 95% CI 0.73-0.81; P<0.0001); low certainty of evidence. The pooled risk of all-cause hospitalization was higher among vaccinated heart failure patients (RR = 1.24, 95% CI 1.13-1.35; P<0.0001), based on two studies; very low certainty of evidence and considerable heterogeneity (I² = 90%). No eligible studies assessed cardiovascular-related hospitalization, non-fatal myocardial infarction, or non-fatal stroke.

CONCLUSIONS

Influenza vaccination appears to reduce adverse cardiovascular events, although the certainty of the evidence is low or very low. Rigorous randomized controlled trial evidence is needed to further examine the protective effect of the influenza vaccine in heart failure patients.

Pneumococcal and influenza vaccination rates among patients with cardiovascular disease

Introduction: Influenza virus infections and pneumococcal pneumonia are associated with significant increases in hospitalization and mortality rates in patients with cardiovascular diseases (CVD). In Turkey, pneumococcal and flu vaccines are recommended for patients with chronic heart disease, adults aged 65 and older and adults who are at risk of pneumonia. Material and Method: This study was conducted between July 2019 and December 2019 among 240 CVD patients. The survey consisted of 29 questions aimed at evaluating the sociodemographic characteristics of the patients, the history of influenza and pneumococcal vaccines, and their knowledge and attitudes towards vaccines. Results: Vaccination rates were low in CVD patients. Last year, only 10% of the participants had been previously vaccinated with the pneumococcal vaccine and 27.75% with the influenza vaccine. While the percentage of vaccination influenza vaccine among university graduates was significantly higher than all other groups, this high was not detected for pneumococcal vaccine. Eighty percent of the participants visited their family physicians regularly in the previous year, while only 61.6% received information about the vaccination from the doctor or nurse. Influenza vaccine (39.2%) was recommended at a higher rate than pneumococcal pneumonia (12.1%) by the physicians or nurses of the participants during the visits. (p

Effects of Influenza Vaccine on Mortality and Cardiovascular Outcomes in Patients With Cardiovascular Disease: A Systematic Review and Meta-Analysis

Background

Influenza infection causes considerable morbidity and mortality in patients with cardiovascular disease. We assessed the effects of the influenza vaccine on mortality and cardiovascular outcomes in patients with cardiovascular disease.

Methods and Results

We searched PubMed, Embase, and the Cochrane Library through January 2020 for randomized controlled trials and observational studies assessing the effects of influenza vaccine on mortality and cardiovascular outcomes in patients with cardiovascular disease. Estimates were reported as random effects risk ratios (RRs) with 95% CIs. Analyses were stratified by study design into randomized controlled trials and observational studies. A total of 16 studies (n=237 058), including 4 randomized controlled trials (n=1667) and 12 observational studies (n=235 391), were identified. Participants' mean age was 69.2±7.01 years, 36.6% were women, 65.1% had hypertension, 31.1% had diabetes mellitus, and 23.4% were smokers. At a median follow‐up duration of 19.5 months, influenza vaccine was associated with a lower risk of all‐cause mortality (RR, 0.75; 95% CI, 0.60–0.93 [P=0.01]), cardiovascular mortality (RR, 0.82; 95% CI, 0.80–0.84 [P<0.001]), and major adverse cardiovascular events (RR, 0.87; 95% CI, 0.80–0.94 [P<0.001]) compared with control. The use of the influenza vaccine was not associated with a statistically significant reduction of myocardial infarction (RR, 0.73; 95% CI, 0.49–1.09 [P=0.12]) compared with control.

Conclusions

Data from both randomized controlled trials and observational studies support the use of the influenza vaccine in adults with cardiovascular disease to reduce mortality and cardiovascular events, as currently supported by clinical guidelines. Clinicians and health systems should continue to promote the influenza vaccine as part of comprehensive secondary prevention.

Effects of influenza vaccination on the risk of cardiovascular and respiratory diseases and all-cause mortality

BACKGROUND

Influenza vaccination is a simple strategy recommended for the prevention of influenza infection and its complications. This meta-analysis aimed to provide current supportive evidence for the breadth and validity of the observed protective effects of influenza vaccination on cardiovascular and respiratory adverse outcomes and all-cause mortality in older adults and in general adult population.

METHODS

We searched PubMed, Embase, Web of Science, and the Cochrane Library to identify all published studies comparing influenza vaccination with placebo from the database inception to November 11, 2018. These included studies reporting the associations of influenza vaccination with the risk of aforementioned adverse outcomes.

RESULTS

The pooled adjusted relative risks among influenza-vaccinated people relative to unvaccinated people for the outcomes of interest were 0.74 (95 % confidence interval [CI] = 0.70-0.78) for cardiovascular diseases (63 studies), 0.82 (95 % CI = 0.75-0.91) for respiratory diseases (29 studies), and 0.57 (95 % CI = 0.51-0.63) for all-cause mortality (43 studies). We performed subgroup analysis of age, sex, and region/country and found that these protective effects were evident in the general adult population and particularly robust in older adults and in those with pre-existing specific diseases.

CONCLUSION

Influenza vaccine is associated with a significant risk reduction of cardiovascular and respiratory adverse outcomes as well as all-cause mortality. Such a preventative measure can benefit the general population as well as those in old age and with pre-existing specific diseases.

Influenza Vaccination and Outcome in Heart Failure

Influenza virus infection is associated with significant morbidity and mortality in patients with chronic diseases including heart failure (HF). Annual influenza vaccination is recommended to prevent infection during the winter months. Data regarding its clinical benefit in HF patients are sparse. The purpose of the study was to evaluate the effect of influenza vaccination on clinical outcome in patients with HF. Consecutive patients with HF at a health maintenance organization were evaluated for influenza vaccination status during the winter season of 2017/2018 and its association with cardiac-related hospitalizations and death during 1-year after vaccination. The study cohort included 6,435 HF patients. A total of 4,440 patient were vaccinated during the winter season (69% of the HF cohort). The vast majority (96%) were vaccinated before the winter months (September to November). Patients vaccinated were older patients with more co-morbidities. Cox regression analysis after adjustment for clinically significant predictors demonstrated that vaccination was associated with reduced mortality (hazard ratio [HR] 0.77, 95% confidence interval [CI] 0.65 to 0.91, p <0.01) as well as reduced death and cardiovascular hospitalizations (HR 0.83 95% CI 0.76 to 0.90, p <0.001). Adjustment for drug therapy demonstrated a similar result with improved outcome with influenza vaccine. Propensity score matched control analysis demonstrated that vaccination was associated with improved survival (HR 0.80, 95% CI 0.67 to 0.95, p <0.01) and reduced death and cardiovascular hospitalizations (HR 0.86, 95% CI 0.79 to 0.94, p <0.001). In conclusion, Influenza vaccination in patients with HF was associated with improved clinical outcome including improved survival and reduced death and hospitalizations.

Influenza vaccination in patients with heart failure: a systematic review and meta-analysis of observational studies

Objective

Despite the progression of treatments over decades, heart failure (HF) is a disease with high morbidity, mortality and economic burden. Influenza infection is an important trigger for cardiovascular (CV) events, including HF. Influenza vaccination has been seen to reduce the risk of CV mortality in patients with coronary disease, but the effect in patients with HF is still unclear. Therefore, we conducted a systematic review to evaluate the effect of influenza vaccination in the morbimortality of patients with HF.

Methods

MEDLINE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Health Technology Assessment and PsycINFO databases (December 2018) were searched for longitudinal studies evaluating influenza vaccination compared with a non-vaccination control group in patients with HF. The risk of bias was assessed according to the ROBINS-I tool. We performed a random-effects meta-analysis to estimate the pooled HRs with 95% CIs, and heterogeneity was evaluated using the I2 statistics.

Results

Six cohort studies evaluating 179 158 patients with HF were included in the meta-analysis. Influenza vaccination was associated with a lower risk of all-cause mortality (HR=0.83; 95% CI 0.76 to 0.91; I2=75%). The effect of the influenza vaccination was not statistically significant in a pooled analysis of CV mortality (HR=0.92, 95% CI 0.73 to 1.15; 2 studies) and of all-cause hospitalisations (HR=1.01, 95% CI 0.92 to 1.11; 2 studies). The majority of outcomes in the included studies had a serious risk of bias and almost all evaluated outcomes had very low Grading of Recommendation, Assessment, Development and Evaluation (GRADE) evidence.

Conclusions

Influenza vaccination was associated with a significant decrease in all-cause mortality risk in patients with HF.

The Effect of Influenza Vaccination on Mortality and Risk of Hospitalization in Patients With Heart Failure: A Systematic Review and Meta-analysis

BACKGROUND

Influenza is a major cause of morbidity and mortality in patients diagnosed with heart failure. The aim of this study was to evaluate the effectiveness of influenza vaccination in this population in terms of reduction in all-cause mortality and rate of hospitalization.

METHODS

We conducted a systematic review and meta-analysis using PubMed and EMBASE entries from January of 2000 through April 2018. Publication bias was examined using the Egger's regression test. Statistical heterogeneity was examined using the Higgins I 2 statistic. Subgroup analyses were performed to examine the effect of vaccination during the influenza and noninfluenza seasons.

RESULTS

We identified 8 studies that included a total of 82 354 patients with heart failure. In patients with heart failure who were vaccinated against influenza, we found a reduced risk of all-cause mortality (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.51-0.87). No evidence of publication bias was found, and the effect was more pronounced during influenza season (HR, 0.49; 95% CI, 0.30-0.69), compared with noninfluenza season (HR, 0.79; 95% CI, 0.68-0.89). In terms of heart failure hospitalizations, we did not identify a statistically significant difference between the cohorts (HR, 0.62; 95% CI, 0.00-1.23).

CONCLUSIONS

Influenza vaccination was associated with a decreased risk of all-cause mortality in patients with heart failure, and this effect was more prominent during the influenza season.