Influenza vaccination and mortality: prospective cohort study of the elderly in a large geographical area

The influenza landscape and vaccination coverage in older adults during the SARS-Cov-2 pandemic: data from Several European Countries and Israel

INTRODUCTION

The Raise Awareness of Influenza Strategies in Europe (RAISE) group gathered information about the healthcare burden of influenza (hospitalizations, intensive care unit [ICU] admissions, and excess deaths), surveillance systems, and the vaccine coverage rate (VCR) in older adults in 18 European countries and Israel.

AREAS COVERED

Published medical literature and official medical documentation on the influenza disease burden in the participating countries were reviewed from 2010/11 until the 2022/23 influenza seasons. Information on the framework for monitoring the disease burden and the provision for ensuring older adults had access to vaccination in their respective countries was provided. Data on influenza VCR in older adults were collected for the 2019/20 to 2022/23 influenza seasons. Data are reported descriptively.

EXPERT OPINION

Influenza presents a significant healthcare burden in older adults. Reporting outcomes across participating countries is heterogeneous, highlighting the need for standardized approaches. Although older adults receive free influenza vaccination, vaccine uptake is highly variable among countries. Moreover, hospitalization rates remain high even in countries reporting a high VCR. Increased awareness and education on the burden of disease and the broader use of improved influenza vaccines for older adults may help reduce the disease burden on this population.

An intercountry comparison of the impact of the paediatric live attenuated influenza vaccine (LAIV) programme across the UK and the Republic of Ireland (ROI), 2010 to 2017

Background

The universal paediatric live attenuated influenza vaccine (LAIV) programme commenced in the United Kingdom (UK) in 2013/2014. Since 2014/2015, all pre-school and primary school children in Scotland and Northern Ireland have been offered the vaccine. England and Wales incrementally introduced the programme with additional school age cohorts being vaccinated each season. The Republic of Ireland (ROI) had no universal paediatric programme before 2017. We evaluated the potential population impact of vaccinating primary school-aged children across the five countries up to the 2016/2017 influenza season.

Methods

We compared rates of primary care influenza-like illness (ILI) consultations, confirmed influenza intensive care unit (ICU) admissions, and all-cause excess mortality using standardised methods. To further quantify the impact, a scoring system was developed where each weekly rate/z-score was scored and summed across each influenza season according to the weekly respective threshold experienced in each country.

Results

Results highlight ILI consultation rates in the four seasons' post-programme, breached baseline thresholds once or not at all in Scotland and Northern Ireland; in three out of the four seasons in England and Wales; and in all four seasons in ROI. No differences were observed in the seasons' post-programme introduction between countries in rates of ICU and excess mortality, although reductions in influenza-related mortality were seen. The scoring system also reflected similar results overall.

Conclusions

Findings of this study suggest that LAIV vaccination of primary school age children is associated with population-level benefits, particularly in reducing infection incidence in primary care.

Clinical impact of influenza vaccination after ST- and non-ST-segment elevation myocardial infarction - insights from the IAMI trial

BACKGROUND

Influenza vaccination early after myocardial infarction (MI) improves prognosis but vaccine effectiveness may differ dependent on type of MI.

METHODS

A total of 2,571 participants were prospectively enrolled in the Influenza vaccination after myocardial infarction (IAMI) trial and randomly assigned to receive in-hospital inactivated influenza vaccine or saline placebo. The trial was conducted at 30 centers in eight countries from October 1, 2016 to March 1, 2020. Here we report vaccine effectiveness in the 2,467 participants with ST-segment elevation MI (STEMI, n = 1,348) or non-ST-segment elevation MI (NSTEMI, n = 1,119). The primary endpoint was the composite of all-cause death, MI, or stent thrombosis at 12 months. Cumulative incidence of the primary and key secondary endpoints by randomized treatment and NSTEMI/STEMI was estimated using the Kaplan-Meier method. Treatment effects were evaluated with formal interaction testing to assess for effect modification.

RESULTS

Baseline risk was higher in participants with NSTEMI. In the NSTEMI group the primary endpoint occurred in 6.5% of participants assigned to influenza vaccine and 10.5% assigned to placebo (hazard ratio [HR], 0.60; 95% CI, 0.39-0.91), compared to 4.1% assigned to influenza vaccine and 4.5% assigned to placebo in the STEMI group (HR, 0.90; 95% CI, 0.54-1.50, P = .237 for interaction). Similar findings were seen for the key secondary endpoints of all-cause death and cardiovascular death. The Kaplan-Meier risk difference in all-cause death at one year was more pronounced in participants with NSTEMI (NSTEMI: HR, 0.47; 95% CI 0.28-0.80, STEMI: HR, 0.86; 95% CI, 0.43-1.70, interaction P = .028).

CONCLUSIONS

The beneficial effect of influenza vaccination on adverse cardiovascular events may be enhanced in patients with NSTEMI compared to those with STEMI.

Effectiveness of influenza vaccination on in-hospital death in older adults with respiratory diseases

Influenza vaccination is associated with lower risk of hospitalization outcomes among older adults with respiratory diseases, but there is limited evidence by disease subtypes and patients' characteristics. This study included patients aged ≥60 years hospitalized for respiratory diseases from the Beijing Urban Employee Basic Medical Insurance database during 6 influenza seasons. Vaccination status was assessed by linking with the Beijing Elderly Influenza Vaccination database. Multi-variable logistic regression was performed to calculate effect estimates. After adjusting for measured and unmeasured confounders, influenza vaccination was associated with a lower risk of in-hospital death among older adults hospitalized for respiratory diseases (odds ratio [95% confidence interval], 0.70 [0.62-0.80]). The protective association was observed among patients with chronic obstructive pulmonary disease (0.67 [0.47-0.98]) as well as those with pneumonia or influenza (0.77 [0.64-0.93]). The protective association was stronger in younger patients (0.59 [0.43-0.81] for <75 and 0.72 [0.63-0.83] for ≥75) and those with fewer comorbidities (0.49 [0.16-1.62] for 0, 0.65 [0.50-0.86] for 1-2, and 0.72 [0.63-0.83] for ≥3 comorbidities). Influenza vaccination was associated with lower risk of in-hospital death among older patients hospitalized for respiratory diseases, with stronger associations in patients with younger age and fewer comorbidities.

Religious Affiliation and Flu Vaccination in Germany: Results of the German Ageing Survey

Our aim was to examine the association between religious affiliation and the likelihood of taking the flu vaccine. Cross-sectional data (year 2014 with n = 7172) were used from the nationally representative German Ageing Survey—covering community-dwelling individuals aged 40 years and over. Multiple logistic regressions showed that compared with individuals without a religious affiliation, individuals with certain religious affiliations had a lower likelihood of taking the flu vaccine. More precisely, the likelihood of taking a flu shot was significantly associated with belonging to the Roman Catholic Church (OR: 0.50, 95% CI: 0.44–0.57), the Protestant Church (OR: 0.68, 0.60–0.77), the Evangelic Free Church (OR: 0.54, 0.35–0.82) and other religious communities (OR: 0.25, 0.14–0.45). The results remained nearly the same when we restricted our analyses to individuals aged 60 years and over (according to existing recommendations for flu vaccination). The association between religious affiliation and the likelihood of taking the flu vaccine was moderated by thoughts about religion and deeds for religion. This knowledge could help to improve the immunization coverage by addressing individuals with certain religious affiliations.

Operationalizing influenza vaccination in an urban safety-net emergency department

INTRODUCTION

Influenza vaccination is a recommended tool in preventing influenza-related illnesses, medical visits, and hospitalizations. With many patients remaining unvaccinated each year, the Emergency Department (ED) represents a unique opportunity to provide vaccinations to patient not yet vaccinated. However, busy urban safety-net EDs maybe challenged to safely execute such a vaccination program. The aim of this quality improvement project was to assess influenza vaccination feasibility in the ED and improve influenza vaccination rates in our community.

METHODS

The quality improvement work-group, comprised of ED physicians, nurses, and pharmacists, designed and implemented an influenza vaccination protocol that aligned with the ED workflow. The outcome measure was the total number of patients vaccinated per month and per influenza season. Process measures included the type of influenza vaccine administered and type of care area within ED. Balancing measures were also included.

RESULTS

Following the initiative, a total of 337 patients received influenza vaccinations in the ED between September 1, 2018 and December 31, 2020 compared to none during the previous influenza season. With each influenza season, the number of vaccinated patients increased from 61 to 134 and 142, respectively. The average age of the patients was 48.23 ± 15.29, 52.89 ± 15.91, and 44.92 ± 18.97 years old. Most patients received the vaccination while roomed in the high acuity section of the adult ED. No adverse effects or automated dispensing cabinet stockouts were observed.

CONCLUSION

Our structured program indicates that influenza vaccine administration to eligible patients is feasible in a busy urban safety-net ED. Piloting new and further developing existing ED-based influenza vaccination programs have the potential to significantly benefit public health.

Clinical impact of a community pharmacy-based health and wellness introductory pharmacy practice experience

OBJECTIVE

To assess the clinical impact of an intensive community pharmacy-based Health and Wellness Introductory Pharmacy Practice Experience (IPPE) completed by second-year (P2) student pharmacists.

DESIGN

The Health and Wellness IPPE was a 1-week rotation developed to provide P2 student pharmacists with opportunities to provide clinical services to patients within the community pharmacy setting. Student pharmacists administered immunizations, performed blood pressure screenings and blood glucose measurements, and provided education to patients under the guidance of licensed pharmacist preceptors.

SETTING AND PARTICIPANTS

Second-year student pharmacists completing a required Health and Wellness IPPE rotation in the community pharmacy setting.

OUTCOMES MEASURED

Student pharmacist interventions were assessed to determine the course's clinical impact, and preceptors were surveyed regarding the feasibility of student pharmacists performing clinical services at their training sites.

RESULTS

A total of 147 student pharmacists completed the IPPE at 89 community pharmacy training sites and administered 9392 injections, 90% of which were influenza vaccinations. Student pharmacists performed 3458 patient health assessments, including measuring patients' blood pressure and blood glucose and reviewing patient education materials. Most preceptors indicated that core activities were feasible during the experience.

CONCLUSION

This study found that implementing a concentrated IPPE focused on immunizations and health screenings allowed student pharmacists to enhance their clinical skills and fulfill a large public health need, improving patient outcomes. Future studies should explore utilizing student pharmacists in community pharmacy settings to expand clinical services offered beyond these 2 services, such as diabetes risk tests, influenza point-of-care testing, and smoking cessation counseling.

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.

Impact of Influenza Vaccination on Mortality in the Oldest Old: A Propensity Score-Matched Cohort Study

Influenza remains a major cause of illness and death in geriatric populations. While the influenza vaccine has successfully reduced morbidity and mortality, its effectiveness is suspected to decrease with age. The aim of this study was to assess the impact of influenza vaccination on all-cause mortality in very old ambulatory subjects. We conducted a prospective cohort study from 1 July 2016 to 31 June 2017 in a large unselected ambulatory population aged over 80 years. We compared all-cause mortality in vaccinated versus unvaccinated subjects after propensity-score matching, to control for age, sex and comorbidities. Among the 9149 patients included, with mean age 86 years, 4380 (47.9%) were vaccinated against influenza. In total, 5253 (57.4%) had at least one chronic disease. The most commonly vaccinated patients were those with chronic respiratory failure (76.3%) and the least commonly vaccinated were those suffering from Parkinson’s disease (28.5%). Overall, 2084 patients (22.8%) died during the study. After propensity score matching, the mortality was evaluated at 20.9% in the vaccinated group and 23.9% in the unvaccinated group (OR = 0.84 [0.75–0.93], p = 0.001). This decrease in mortality in the vaccinated group persisted whatever the age and Charlson Comorbidity index. In conclusion, nearly a half of this ambulatory elderly population received Influenza vaccine. After adjustment on comorbidities, influenza vaccination was associated with a significant decrease in all-cause mortality, even in the eldest multimorbid population. Improving immunization coverage in this frail older population is urgently needed.

Vaccines for preventing influenza in the elderly

BACKGROUND

The consequences of influenza in the elderly (those age 65 years or older) are complications, hospitalisations, and death. The primary goal of influenza vaccination in the elderly is to reduce the risk of death among people who are most vulnerable. This is an update of a review published in 2010. Future updates of this review will be made only when new trials or vaccines become available. Observational data included in previous versions of the review have been retained for historical reasons but have not been updated because of their lack of influence on the review conclusions.

OBJECTIVES

To assess the effects (efficacy, effectiveness, and harm) of vaccines against influenza in the elderly.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library 2016, Issue 11), which includes the Cochrane Acute Respiratory Infections Group's Specialised Register; MEDLINE (1966 to 31 December 2016); Embase (1974 to 31 December 2016); Web of Science (1974 to 31 December 2016); CINAHL (1981 to 31 December 2016); LILACS (1982 to 31 December 2016); WHO International Clinical Trials Registry Platform (ICTRP; 1 July 2017); and ClinicalTrials.gov (1 July 2017).

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs assessing efficacy against influenza (laboratory-confirmed cases) or effectiveness against influenza-like illness (ILI) or safety. We considered any influenza vaccine given independently, in any dose, preparation, or time schedule, compared with placebo or with no intervention. Previous versions of this review included 67 cohort and case-control studies. The searches for these trial designs are no longer updated.

DATA COLLECTION AND ANALYSIS

Review authors independently assessed risk of bias and extracted data. We rated the certainty of evidence with GRADE for the key outcomes of influenza, ILI, complications (hospitalisation, pneumonia), and adverse events. We have presented aggregate control group risks to illustrate the effect in absolute terms. We used them as the basis for calculating the number needed to vaccinate to prevent one case of each event for influenza and ILI outcomes.

MAIN RESULTS

We identified eight RCTs (over 5000 participants), of which four assessed harms. The studies were conducted in community and residential care settings in Europe and the USA between 1965 and 2000. Risk of bias reduced our certainty in the findings for influenza and ILI, but not for other outcomes.Older adults receiving the influenza vaccine may experience less influenza over a single season compared with placebo, from 6% to 2.4% (risk ratio (RR) 0.42, 95% confidence interval (CI) 0.27 to 0.66; low-certainty evidence). We rated the evidence as low certainty due to uncertainty over how influenza was diagnosed. Older adults probably experience less ILI compared with those who do not receive a vaccination over the course of a single influenza season (3.5% versus 6%; RR 0.59, 95% CI 0.47 to 0.73; moderate-certainty evidence). These results indicate that 30 people would need to be vaccinated to prevent one person experiencing influenza, and 42 would need to be vaccinated to prevent one person having an ILI.The study providing data for mortality and pneumonia was underpowered to detect differences in these outcomes. There were 3 deaths from 522 participants in the vaccination arm and 1 death from 177 participants in the placebo arm, providing very low-certainty evidence for the effect on mortality (RR 1.02, 95% CI 0.11 to 9.72). No cases of pneumonia occurred in one study that reported this outcome (very low-certainty evidence). No data on hospitalisations were reported. Confidence intervaIs around the effect of vaccines on fever and nausea were wide, and we do not have enough information about these harms in older people (fever: 1.6% with placebo compared with 2.5% after vaccination (RR 1.57, 0.92 to 2.71; moderate-certainty evidence)); nausea (2.4% with placebo compared with 4.2% after vaccination (RR 1.75, 95% CI 0.74 to 4.12; low-certainty evidence)).

AUTHORS' CONCLUSIONS

Older adults receiving the influenza vaccine may have a lower risk of influenza (from 6% to 2.4%), and probably have a lower risk of ILI compared with those who do not receive a vaccination over the course of a single influenza season (from 6% to 3.5%). We are uncertain how big a difference these vaccines will make across different seasons. Very few deaths occurred, and no data on hospitalisation were reported. No cases of pneumonia occurred in one study that reported this outcome. We do not have enough information to assess harms relating to fever and nausea in this population.The evidence for a lower risk of influenza and ILI with vaccination is limited by biases in the design or conduct of the studies. Lack of detail regarding the methods used to confirm the diagnosis of influenza limits the applicability of this result. The available evidence relating to complications is of poor quality, insufficient, or old and provides no clear guidance for public health regarding the safety, efficacy, or effectiveness of influenza vaccines for people aged 65 years or older. Society should invest in research on a new generation of influenza vaccines for the elderly.

Real-time real-world analysis of seasonal influenza vaccine effectiveness: method development and assessment of a population-based cohort in Stockholm County, Sweden, seasons 2011/12 to 2014/15

Real-world estimates of seasonal influenza vaccine effectiveness (VE) are important for early detection of vaccine failure. We developed a method for evaluating real-time in-season vaccine effectiveness (IVE) and overall seasonal VE. In a retrospective, register-based, cohort study including all two million individuals in Stockholm County, Sweden, during the influenza seasons from 2011/12 to 2014/15, vaccination status was obtained from Stockholm’s vaccine register. Main outcomes were hospitalisation or primary care visits for influenza (International Classification of Disease (ICD)-10 codes J09-J11). VE was assessed using Cox multivariate stratified and non-stratified analyses adjusting for age, sex, socioeconomic status, comorbidities and previous influenza vaccinations. Stratified analyses showed moderate VE in prevention of influenza hospitalisations among chronically ill adults ≥ 65 years in two of four seasons, and lower but still significant VE in one season; 53% (95% confidence interval (CI): 33–67) in 2012/13, 55% (95% CI: 25–73) in 2013/14 and 18% (95% CI: 3–31) in 2014/15. In conclusion, seasonal influenza vaccination was associated with substantial reductions in influenza-specific hospitalisation, particularly in adults ≥ 65 years with underlying chronic conditions. With the use of population-based patient register data on influenza-specific outcomes it will be possible to obtain real-time estimates of seasonal influenza VE.

Frequency and impact of confounding by indication and healthy vaccinee bias in observational studies assessing influenza vaccine effectiveness: a systematic review

Background

Evidence on influenza vaccine effectiveness (VE) is commonly derived from observational studies. However, these studies are prone to confounding by indication and healthy vaccinee bias. We aimed to systematically investigate these two forms of confounding/bias.

Methods

Systematic review of observational studies reporting influenza VE and indicators for bias and confounding. We assessed risk of confounding by indication and healthy vaccinee bias for each study and calculated ratios of odds ratios (crude/adjusted) to quantify the effect of confounder adjustment. VE-estimates during and outside influenza seasons were compared to assess residual confounding by healthy vaccinee effects.

Results

We identified 23 studies reporting on 11 outcomes. Of these, 19 (83 %) showed high risk of bias: Fourteen due to confounding by indication, two for healthy vaccinee bias, and three studies showed both forms of confounding/bias. Adjustment for confounders increased VE on average by 12 % (95 % CI: 7–17 %; all-cause mortality), 9 % (95 % CI: 4–14 %; all-cause hospitalization) and 7 % (95 % CI: 4–10 %; influenza-like illness). Despite adjustment, nine studies showed residual confounding as indicated by significant off-season VE-estimates. These were observed for five outcomes, but more frequently for all-cause mortality as compared to other outcomes (p = 0.03) and in studies which indicated healthy vaccinee bias at baseline (p = 0.01).

Conclusions

Both confounding by indication and healthy vaccinee bias are likely to operate simultaneously in observational studies on influenza VE. Although adjustment can correct for confounding by indication to some extent, the resulting estimates are still prone to healthy vaccinee bias, at least as long as unspecific outcomes like all-cause mortality are used. Therefore, cohort studies using administrative data bases with unspecific outcomes should no longer be used to measure the effects of influenza vaccination.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-015-1154-y) contains supplementary material, which is available to authorized users.

Methodological challenges in measuring vaccine effectiveness using population cohorts in low resource settings

•

We discuss methodological challenges for evaluating vaccine effectiveness using cohorts.

•

No single set of definitions or analytical approach can address all possible biases.

•

Careful consideration of denominator, exposure and outcome definitions is needed.

•

Sensitivity analyses are crucial to examine assumptions and explore subtle relationships.

Post-licensure real world evaluation of vaccine implementation is important for establishing evidence of vaccine effectiveness (VE) and programme impact, including indirect effects. Large cohort studies offer an important epidemiological approach for evaluating VE, but have inherent methodological challenges.

Since March 2012, we have conducted an open prospective cohort study in two sites in rural Malawi to evaluate the post-introduction effectiveness of 13-valent pneumococcal conjugate vaccine (PCV13) against all-cause post-neonatal infant mortality and monovalent rotavirus vaccine (RV1) against diarrhoea-related post-neonatal infant mortality. Our study sites cover a population of 500,000, with a baseline post-neonatal infant mortality of 25 per 1000 live births.

We conducted a methodological review of cohort studies for vaccine effectiveness in a developing country setting, applied to our study context. Based on published literature, we outline key considerations when defining the denominator (study population), exposure (vaccination status) and outcome ascertainment (mortality and cause of death) of such studies. We assess various definitions in these three domains, in terms of their impact on power, effect size and potential biases and their direction, using our cohort study for illustration. Based on this iterative process, we discuss the pros and cons of our final per-protocol analysis plan. Since no single set of definitions or analytical approach accounts for all possible biases, we propose sensitivity analyses to interrogate our assumptions and methodological decisions.

In the poorest regions of the world where routine vital birth and death surveillance are frequently unavailable and the burden of disease and death is greatest We conclude that provided the balance between definitions and their overall assumed impact on estimated VE are acknowledged, such large scale real-world cohort studies can provide crucial information to policymakers by providing robust and compelling evidence of total benefits of newly introduced vaccines on reducing child mortality.

Enhanced Estimates of the Influenza Vaccination Effect in Preventing Mortality: A Prospective Cohort Study

Mortality is a major end-point in the evaluation of influenza vaccine effectiveness. However, this effect is not well known, since most previous studies failed to show good control of biases. We aimed to estimate the effectiveness of influenza vaccination in preventing all-cause mortality in community-dwelling seniors.Since 2009, a population-based cohort study using healthcare databases has been conducted in Navarra, Spain. In 2 late influenza seasons, 2011/2012 and 2012/2013, all-cause mortality in the period January to May was compared between seniors (65 years or over) who received the trivalent influenza vaccine and those who were unvaccinated, adjusting for demographics, major chronic conditions, dependence, previous hospitalization, and pneumococcal vaccination.The cohort included 103,156 seniors in the 2011/2012 season and 105,140 in the 2012/2013 season (58% vaccinated). Seniors vaccinated in the previous season who discontinued vaccination (6% of the total) had excess mortality and were excluded to prevent frailty bias. The final analysis included 80,730 person-years and 2778 deaths. Vaccinated seniors had 16% less all-cause mortality than those unvaccinated (adjusted rate ratio [RR] = 0.84; 95% confidence interval 0.76-0.93). This association disappeared in the post-influenza period (adjusted RR = 0.96; 95% confidence interval 0.85-1.09). A similar comparison did not find an association in January to May of the 2009/2010 pandemic season (adjusted RR = 0.98; 95% confidence interval 0.84-1.14), when no effect of the seasonal vaccine was expected. On average, 1 death was prevented for every 328 seniors vaccinated: 1 for every 649 in the 65 to 74 year age group and 1 for every 251 among those aged 75 and over.These results suggest a moderate preventive effect and a high potential impact of the seasonal influenza vaccine against all-cause mortality. This reinforces the recommendation of annual influenza vaccination in seniors.

The management of community-acquired pneumonia in the elderly

Pneumonia is one of the main causes of morbidity and mortality in the elderly. The elderly population has exponentially increased in the last decades and the current epidemiological trends indicate that it is expected to further increase. Therefore, recognizing the special needs of older people is of paramount importance. In this review we address the main differences between elderly and adult patients with pneumonia. We focus on several aspects, including the atypical clinical presentation of pneumonia in the elderly, the methods to assess severity of illness, the appropriate setting of care, and the management of comorbidities. We also discuss how to approach the common complications of severe pneumonia, including acute respiratory failure and severe sepsis. Moreover, we debate whether or not elderly patients are at higher risk of infection due to multi-drug resistant pathogens and which risk factors should be considered when choosing the antibiotic therapy. We highlight the differences in the definition of clinical stability and treatment failure between adults and elderly patients. Finally, we review the main outcomes, preventive and supportive measures to be considered in elderly patients with pneumonia.

The pandemic influenza A (H1N1) 2009 vaccine does not increase the mortality rate of idiopathic interstitial pneumonia: a matched case-control study

Background

Evidence regarding the mortality rate after administration of the pandemic influenza A (H1N1) 2009 vaccine on patients with underlying diseases is currently scarce. We conducted a case-control study in Japan to compare the mortality rates of patients with idiopathic interstitial pneumonia after the vaccines were administered and were not administered.

Methods

Between October 2009 and March 2010, we collected clinical records in Japan and conducted a 1∶1 matched case-control study. Patients with idiopathic interstitial pneumonia who died during this period were considered case patients, and those who survived were considered control patients. We determined and compared the proportion of each group that received the pandemic influenza A (H1N1) 2009 vaccine and estimated the odds ratio. Finally, we conducted simulations that compensated for the shortcomings of the study associated with adjusted severity of idiopathic interstitial pneumonia.

Results

The case and control groups each comprised of 75 patients with idiopathic interstitial pneumonia. The proportion of patients who received the pandemic influenza A (H1N1) 2009 vaccine was 30.7% and 38.7% for the case and control groups, respectively. During that winter, the crude conditional odds ratio of mortality was 0.63 (95% confidence interval, 0.25–1.47) and the adjusted conditional odds ratio was 1.18 (95% confidence interval, 0.33–4.49); neither was significant. The simulation study showed more accurate conditional odds ratios of 0.63–0.71.

Conclusions

In our study, we detected no evidence that the influenza A (H1N1) 2009 vaccine increased the mortality rate of patients with idiopathic interstitial pneumonia. The results, however, are limited by the small sample size and low statistical power. A larger-scale study is required.

Further evidence for bias in observational studies of influenza vaccine effectiveness: the 2009 influenza A(H1N1) pandemic

Preinfluenza periods have been used to test for uncontrolled confounding in studies of influenza vaccine effectiveness, but some authors have claimed that confounding differs in preinfluenza and influenza periods. We tested this claim by comparing estimates of the vaccine-mortality association during the 2009/2010 influenza year, when there was essentially no circulation of seasonal influenza in the United States, and 2007/2008, a typical influenza year. We pooled data on seniors (adults aged ≥65 years) from 7 US managed care organizations that participated in the Vaccine Safety Datalink Project. We defined influenza vaccination, all-cause mortality, and potential confounders from administrative databases. We quantified the vaccine-mortality association using Cox regression. During 2007/2008, the adjusted hazard ratio was 0.44 prior to influenza season, 0.62 during influenza season, and 0.71 after influenza season. A similar pattern was observed during 2009/2010, when any effect of seasonal influenza vaccine observed during all time periods must have resulted from confounding: 0.65 during the autumn, 0.80 during the winter, and 0.84 during the summer. In a year with minimal seasonal influenza, we found no evidence that confounding in autumn preinfluenza periods is qualitatively different from confounding in winter. This supports the use of preinfluenza periods as control time periods in studies of influenza vaccine effectiveness.

The impact of targeting all elderly persons in England and Wales for yearly influenza vaccination: excess mortality due to pneumonia or influenza and time trend study

OBJECTIVE

To investigate the impact on mortality due to pneumonia or influenza of the change from risk-based to age group-based targeting of the elderly for yearly influenza vaccination in England and Wales.

DESIGN

Excess mortality estimated using time series of deaths registered to pneumonia or influenza, accounting for seasonality, trend and artefacts. Non-excess mortality plotted as proxy for long-term trend in mortality.

SETTING

England and Wales.

PARTICIPANTS

Persons aged 65-74 and 75+ years whose deaths were registered to underlying pneumonia or influenza between 1975/1976 and 2004/2005.

OUTCOME MEASURES

Multiplicative effect on average excess pneumonia and influenza deaths each winter in the 4-6 winters since age group-based targeting of vaccination was introduced (in persons aged 75+ years from 1998/1999; in persons aged 65+ years from 2000/2001), estimated using multivariable regression adjusted for temperature, antigenic drift and vaccine mismatch, and stratified by dominant circulating influenza subtype. Trend in baseline weekly pneumonia and influenza death rates.

RESULTS

There is a suggestion of lower average excess mortality in the six winters after age group-based targeting began compared to before, but the CI for the 65-74 years age group includes no difference. Trend in baseline pneumonia and influenza mortality shows an apparent downward turning point around 2000 for the 65-74 years age group and from the mid-1990s in the 75+ years age group.

CONCLUSIONS

There is weakly supportive evidence that the marked increases in vaccine coverage accompanying the switch from risk-based to age group-based targeting of the elderly for yearly influenza vaccination in England and Wales were associated with lower levels of pneumonia and influenza mortality in older people in the first 6 years after age group-based targeting began. The possible impact of these policy changes is observed as weak evidence for lower average excess mortality as well as a turning point in baseline mortality coincident with the changes.

Vaccination against seasonal influenza is effective in Japanese patients with rheumatoid arthritis enrolled in a large observational cohort

OBJECTIVE

To investigate the effectiveness of influenza vaccination in patients with rheumatoid arthritis (RA) from a large practice-based cohort.

METHOD

Patients with RA enrolled in the Institute of Rheumatology, Rheumatoid Arthritis (IORRA) cohort completed self-administered questionnaires as part of the April IORRA surveys of 2001, 2002, 2003, and 2007, which included their influenza vaccination status and occurrence of an actual influenza attack. Vaccine coverage rate and attack rates were calculated in each season. Relative risks (RRs) of vaccination for an actual influenza attack were evaluated and risk factors for influenza infection were determined by multiple logistic regression analysis.

RESULTS

Data from 3529, 4518, 4816, and 4872 patients in the 2000/01, 2001/02, 2002/03, and 2006/07 seasons, respectively, were analysed. Coverage rates were increased from 12.2% in the 2000/01 season to 38.7% in the 2006/07 season. For each season, the attack rates in vaccinated patients trended lower than the rates in unvaccinated patients but the differences were not significant; however, by combining these four seasonal results, the attack rate was significantly lower for vaccinated patients [RR 0.83, 95% confidence interval (CI) 0.71-0.95, p < 0.01]. Male gender [odds ratio (OR) 1.48, 95% CI 1.25-1.76, p < 0.001] was associated with increased risk whereas vaccination was associated with reduced risk for influenza attack (OR 0.76, 95% CI 0.63-0.91, p < 0.01). There were no associations between influenza attacks and RA disease activity, treatment with methotrexate (MTX) or corticosteroids.

CONCLUSION

Influenza vaccination was effective in patients with RA regardless of disease activity or treatment.

Implementing an influenza vaccination programme for adults aged ≥65 years in Poland: a cost-effectiveness analysis

BACKGROUND AND OBJECTIVES

Influenza is a common respiratory disease occurring in seasonal patterns, and may lead to severe complications in frail populations such as the elderly. In Poland, influenza vaccination is recommended for people aged ≥65 years; however the vaccine coverage rate in the elderly is very low. The fact that influenza vaccine is neither reimbursed by the National Health Insurance (Narodowy Fundusz Zdrowia [NFZ]) nor financed via a National Immunization Program (NIP) could be a reason for the low coverage rate. This study assessed the cost effectiveness of the full reimbursement of an influenza vaccination programme in Poland for people aged ≥65 years.

METHODS

A decision-analytic model was developed to compare costs and outcomes associated with the current situation in which influenza vaccination is not reimbursed and a new situation in which it would be fully covered by the NFZ. The model was parameterized to Poland using data from the literature and from the Central Statistic Office of Poland. Within the elderly population, 50% were considered to be at high risk of influenza complications. An influenza attack rate of 3.5% was used for calculation purposes. Influenza-associated hospitalizations and death rates were estimated at 439.9 per 100 000 person-years and 79.1 per 100 000 person-years, respectively. Cost estimates were derived from a cost study conducted in Poland. Costs are presented in Polish Zloty (PLN) [2009 mean exchange rate: 1 PLN = €0.232]. Only direct medical costs were included to fit to the NFZ perspective. To reflect the seasonality of influenza, a time horizon of 1 year was chosen. Life-years and quality-adjusted life-years (QALYs) accumulated over future years were discounted at a rate of 5% as recommended by Polish guidelines. Deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

In Poland, the introduction of the public funding of influenza vaccination for people aged ≥65 years would cost PLN 79 million when an increase in coverage rate from 13.5% to 40% is assumed. 23 900 cases of influenza, 1777 hospitalizations and 548 premature deaths would be averted each year due to the influenza vaccination programme. Fifty-seven persons would need to be vaccinated to prevent one case of influenza. To prevent one hospitalization and one death due to influenza, 842 and 2809 individuals would need to be vaccinated, respectively. The new strategy would be very cost effective compared with the current situation with an incremental cost-effectiveness ratio (ICER) of PLN26 118/QALY, which is below the 2009 yearly gross domestic product (GDP) per capita. Deterministic sensitivity analyses demonstrated that the most influential variables for the ICER were vaccine efficacy against death, excess hospitalization rate, utility norms, influenza attack rate, vaccine efficacy against hospitalization, and discount rates. All ICERs computed were below the threshold of 3 GDP per capita. From the probabilistic analysis, the proposed new influenza vaccination programme, if implemented, was predicted to be cost effective from the NFZ perspective with a probability of 100%, given the same threshold.

CONCLUSION

Implementing a vaccination programme in Poland in which influenza vaccination would be fully reimbursed by the NFZ for people aged ≥65 years would be a very cost-effective strategy.

Swedish guidelines on the management of community-acquired pneumonia in immunocompetent adults--Swedish Society of Infectious Diseases 2012

This document presents the 2012 evidence based guidelines of the Swedish Society of Infectious Diseases for the in- hospital management of adult immunocompetent patients with community-acquired pneumonia (CAP). The prognostic score 'CRB-65' is recommended for the initial assessment of all CAP patients, and should be regarded as an aid for decision-making concerning the level of care required, microbiological investigation, and antibiotic treatment. Due to the favourable antibiotic resistance situation in Sweden, an initial narrow-spectrum antibiotic treatment primarily directed at Streptococcus pneumoniae is recommended in most situations. The recommended treatment for patients with severe CAP (CRB-65 score 2) is penicillin G in most situations. In critically ill patients (CRB-65 score 3-4), combination therapy with cefotaxime/macrolide or penicillin G/fluoroquinolone is recommended. A thorough microbiological investigation should be undertaken in all patients, including blood cultures, respiratory tract sampling, and urine antigens, with the addition of extensive sampling for more uncommon respiratory pathogens in the case of severe disease. Recommended measures for the prevention of CAP include vaccination for influenza and pneumococci, as well as smoking cessation.

Guidelines for the management of adult lower respiratory tract infections--summary

This document is an update of Guidelines published in 2005 and now includes scientific publications through to May 2010. It provides evidence-based recommendations for the most common management questions occurring in routine clinical practice in the management of adult patients with LRTI. Topics include management outside hospital, management inside hospital (including community-acquired pneumonia (CAP), acute exacerbations of COPD (AECOPD), acute exacerbations of bronchiectasis) and prevention. The target audience for the Guideline is thus all those whose routine practice includes the management of adult LRTI.

Efficacy and effectiveness of influenza vaccines: a systematic review and meta-analysis

BACKGROUND

No published meta-analyses have assessed efficacy and effectiveness of licensed influenza vaccines in the USA with sensitive and highly specific diagnostic tests to confirm influenza.

METHODS

We searched Medline for randomised controlled trials assessing a relative reduction in influenza risk of all circulating influenza viruses during individual seasons after vaccination (efficacy) and observational studies meeting inclusion criteria (effectiveness). Eligible articles were published between Jan 1, 1967, and Feb 15, 2011, and used RT-PCR or culture for confirmation of influenza. We excluded some studies on the basis of study design and vaccine characteristics. We estimated random-effects pooled efficacy for trivalent inactivated vaccine (TIV) and live attenuated influenza vaccine (LAIV) when data were available for statistical analysis (eg, at least three studies that assessed comparable age groups).

FINDINGS

We screened 5707 articles and identified 31 eligible studies (17 randomised controlled trials and 14 observational studies). Efficacy of TIV was shown in eight (67%) of the 12 seasons analysed in ten randomised controlled trials (pooled efficacy 59% [95% CI 51-67] in adults aged 18-65 years). No such trials met inclusion criteria for children aged 2-17 years or adults aged 65 years or older. Efficacy of LAIV was shown in nine (75%) of the 12 seasons analysed in ten randomised controlled trials (pooled efficacy 83% [69-91]) in children aged 6 months to 7 years. No such trials met inclusion criteria for children aged 8-17 years. Vaccine effectiveness was variable for seasonal influenza: six (35%) of 17 analyses in nine studies showed significant protection against medically attended influenza in the outpatient or inpatient setting. Median monovalent pandemic H1N1 vaccine effectiveness in five observational studies was 69% (range 60-93).

INTERPRETATION

Influenza vaccines can provide moderate protection against virologically confirmed influenza, but such protection is greatly reduced or absent in some seasons. Evidence for protection in adults aged 65 years or older is lacking. LAIVs consistently show highest efficacy in young children (aged 6 months to 7 years). New vaccines with improved clinical efficacy and effectiveness are needed to further reduce influenza-related morbidity and mortality.

FUNDING

Alfred P Sloan Foundation.

Guidelines for the management of adult lower respiratory tract infections--full version

This document is an update of Guidelines published in 2005 and now includes scientific publications through to May 2010. It provides evidence-based recommendations for the most common management questions occurring in routine clinical practice in the management of adult patients with LRTI. Topics include management outside hospital, management inside hospital (including community-acquired pneumonia (CAP), acute exacerbations of COPD (AECOPD), acute exacerbations of bronchiectasis) and prevention. Background sections and graded evidence tables are also included. The target audience for the Guideline is thus all those whose routine practice includes the management of adult LRTI.

Research priorities for high-quality geriatric emergency care: medication management, screening, and prevention and functional assessment

BACKGROUND

Geriatric adults represent an increasing proportion of emergency department (ED) users and can be particularly vulnerable to acute illnesses. Health care providers have recently begun to focus on the development of quality indicators (QIs) to define a minimal standard of care.

OBJECTIVES

The original objective of this project was to develop additional ED-specific QIs for older patients within the domains of medication management, screening and prevention, and functional assessment, but the quantity and quality of evidence were insufficient to justify unequivocal minimal standards of care for these three domains. Accordingly, the authors modified the project objectives to identify key research opportunities within these three domains that can be used to develop QIs in the future.

METHODS

Each domain was assigned one or two content experts who created potential QIs based on a systematic review of the literature, supplemented by expert opinion. Candidate QIs were then reviewed by four groups: the Society for Academic Emergency Medicine (SAEM) Geriatric Task Force, the SAEM Geriatric Interest Group, and audiences at the 2008 SAEM Annual Meeting and the 2009 American Geriatrics Society Annual Meeting, using anonymous audience response system technology as well as verbal and written feedback.

RESULTS

High-quality evidence based on patient-oriented outcomes was insufficient or nonexistent for all three domains. The participatory audiences did not reach a consensus on any of the proposed QIs. Key research questions for medication management (three), screening and prevention (two), and functional assessment (three) are presented based on proposed QIs that the majority of participants accepted.

CONCLUSIONS

In assessing a minimal standard of care by which to systematically derive geriatric QIs for medication management, screening and prevention, and functional assessment, compelling clinical research evidence is lacking. Patient-oriented research questions that are essential to justify and characterize future QIs within these domains are described.

From vaccine practice to vaccine science: the contribution of human immunology to the prevention of infectious disease

Over the past 50 years, the practice of vaccination has reached the important goal of reducing many of the diseases that afflicted humanity in past centuries. A better understanding of immunological mechanisms underlying the induction of immune protection and the advent of new technology led to improved vaccine preparations based on purified microbial antigens and new adjuvants able to boost both humoral and cellular immune responses. Despite these tremendous advances, much remains to be done. The emergence of new pathogens, the spread of strains resistant to antibiotics and the enormous increase in latent infections are urgently demanding more and more effective vaccines. Understanding the immunological mechanisms that mediate resistance against infections would certainly provide valuable information for the design of new candidate vaccines.

The use of immunization registry-based data in vaccine effectiveness studies

Vaccine effectiveness (VE) studies provide a measure of population-based vaccine performance by combining immunization history data with rates of disease incidence. This review assessed the feasibility of using electronic immunization registry data sources in VE studies. Electronic databases were searched through January 31, 2010. Out of 17 studies, only one paper assessed data accuracy (71%), and three papers assessed population coverage of the registry (estimates ranged from 25% to 90%). This review shows that registry-based data sources can be used to conduct VE studies in a variety of settings and populations. However, we found little information regarding the quality of this data source in VE studies and future evaluations should investigate their reliability, accuracy, and potential bias.

Increased risk of hospital admission for influenza in patients with celiac disease: a nationwide cohort study in Sweden

OBJECTIVES

Although earlier studies suggest an increased risk of infectious disease in celiac disease (CD), data on the risk of influenza in patients with CD are limited. We examined the risk of hospital admission for influenza in CD patients, but for comparative reasons also in individuals with small-intestinal inflammation or normal mucosa but positive CD serology.

METHODS

In 2006-2008, we collected duodenal/jejunal biopsy data on CD (Marsh 3: villous atrophy, VA; n=29,008 unique individuals) and inflammation (Marsh 1-2; n=13,200) from all 28 pathology departments in Sweden. A third regional cohort consisted of 3,709 individuals with positive CD serology but normal mucosa (Marsh 0). The biopsies were performed between 1969 and 2008. Through linkage with the Swedish Hospital Discharge Register, we estimated the risk of hospital admission for influenza compared with that of 224,114 age- and sex-matched controls from the general population.

RESULTS

Individuals with CD were at increased risk of hospital admission for influenza (hazard ratio (HR)=2.1; 95% confidence interval (CI)=1.6-2.7; n=81). The absolute risk of influenza was 30/100,000 person-years (excess risk: 16/100,000 person-years). Furthermore, children with CD were at increased risk of influenza (HR=2.5; 95% CI=1.3-4.8). Whereas individuals with inflammation without VA were also at increased risk of influenza (HR=1.9; 95% CI=1.4-2.5), individuals with normal mucosa but positive CD serology were not (HR=1.2; 95% CI=0.5-3.0).

CONCLUSIONS

This study found an increased risk of hospital admission for influenza in patients with CD.

Influenza vaccination and all-cause mortality in community-dwelling elderly in Ontario, Canada, a cohort study

The objective of this study was to evaluate the effectiveness of influenza vaccines in reducing all-cause mortality among community-dwelling elderly. We included 25,922 Ontario residents over age 65 who responded to population health surveys. After full adjustment, influenza vaccination was associated with a statistically significant reduction in all-cause mortality during influenza seasons (hazard ratio (HR)=0.61; 95% CI 0.47-0.79). Contrary to expectations, statistically significant associations between influenza vaccination and mortality were also observed during periods preceding (HR=0.55; 95% CI 0.40-0.75) and following (HR=0.74; 95% CI 0.59-0.94) influenza seasons, indicating the presence of residual confounding. Adjustment for functional status indicators, excluding individuals with high one-year predicted mortality at baseline, and moving the start date of follow-up failed to eliminate the refractory confounding. Since observational studies are prone to bias, future efforts to estimate vaccine effectiveness in the elderly should strive to minimize bias through improved data quality, novel data sources, and/or new analytical techniques.

Influenza vaccine coverage in age-related risk groups in Poland, 2004-2007

Routine vaccination of certain groups of persons, including children and the elderly might provide additional protection to persons at risk for influenza complications and reduce the overall influenza burden. The aim of the paper was to estimate the influenza vaccine coverage in persons aged 0-4 years and > 65 years in Poland in 2004-2007. Official data collected by National Institute of Hygiene, National Institute of Public Health and Central Statistical Office were analyzed. Among vaccinations performed in all persons, the percentage of vaccinations performed in children aged 0-4 years varied from 1.6% to 2.0%. The estimated vaccination coverage in this age group of population was < 2%. Among persons aged > 65 years the influenza vaccine coverage increased from 7% in 2004 to 14% in 2007. Subjects aged > 65 years represented 25-36% of all vaccinated individuals. The influenza vaccination rates among age-related risk groups in Poland remain low. No or very low increase in a total vaccination coverage rates, as demonstrated in our paper, indicates that meeting the WHO targets concerning influenza vaccination coverage will be very difficult, if no further action is taken concerning vaccine uptake.

Vaccines for preventing influenza in the elderly

BACKGROUND

Vaccines have been the main global weapon to minimise the impact of influenza in the elderly for the last four decades and are recommended worldwide for individuals aged 65 years or older. The primary goal of influenza vaccination in the elderly is to reduce the risk of complications among persons who are most vulnerable.

OBJECTIVES

To assess the effectiveness of vaccines in preventing influenza, influenza-like illness (ILI), hospital admissions, complications and mortality in the elderly. To identify and appraise comparative studies evaluating the effects of influenza vaccines in the elderly. To document types and frequency of adverse effects associated with influenza vaccines in the elderly.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), which contains the Cochrane Acute Respiratory Infections (ARI) Group's Specialised Register (The Cochrane Library 2009, issue 4); MEDLINE (January 1966 to October Week 1 2009); EMBASE (1974 to October 2009) and Web of Science (1974 to October 2009).

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-RCTs, cohort and case-control studies assessing efficacy against influenza (laboratory-confirmed cases) or effectiveness against influenza-like illness (ILI) or safety. Any influenza vaccine given independently, in any dose, preparation or time schedule, compared with placebo or with no intervention was considered.

DATA COLLECTION AND ANALYSIS

We grouped reports first according to the setting of the study (community or long-term care facilities) and then by level of viral circulation and vaccine matching. We further stratified by co-administration of pneumococcal polysaccharide vaccine (PPV) and by different types of influenza vaccines. We analysed the following outcomes: influenza, influenza-like illness, hospital admissions, complications and deaths.

MAIN RESULTS

We included 75 studies. Overall we identified 100 data sets. We identified one RCT assessing efficacy and effectiveness. Although this seemed to show an effect against influenza symptoms it was underpowered to detect any effect on complications (1348 participants). The remainder of our evidence base included non-RCTs. Due to the general low quality of non-RCTs and the likely presence of biases, which make interpretation of these data difficult and any firm conclusions potentially misleading, we were unable to reach clear conclusions about the effects of the vaccines in the elderly.

AUTHORS' CONCLUSIONS

The available evidence is of poor quality and provides no guidance regarding the safety, efficacy or effectiveness of influenza vaccines for people aged 65 years or older. To resolve the uncertainty, an adequately powered publicly-funded randomised, placebo-controlled trial run over several seasons should be undertaken.

Use of CD40L immunoconjugates to overcome the defective immune response to vaccines for infections and cancer in the aged

Multiple investigators have reported the presence of defects in the immune response of the elderly [Castle In: Clin Infect Dis 31:578, 2000; Ortqvist et al. In: Eur Respir J 30:414-422, 2007; Saurwein-Teissl et al. In: J Immunol 168:5893, 2002; Haynes et al. In: Proc Natl Acad Sci USA 100:15053-15058, 2003]. These defects reduce the magnitude of the immune response to infection and to vaccination. In individuals greater than 55 years of age, the probability of developing a fully protective neutralizing antibody response to the yearly multivalent particle inactivated influenza vaccine is less than 20% [Jefferson et al. In: Lancet 264:1165-1174, 2005; Goodwin et al. In: Vaccine 24:1159-1169, 2006; Jackson et al. In: Lancet 372:398-405, 2008; Simonsen and Taylor In: Lancet 7:658-666, 2007]. The defects in the aged immune system that are responsible for this limited response to vaccination in the older age groups include functional defects of the antigen presenting cells, functional defects in CD4 helper CD4 T cells and monocytes, and an altered microenvironment [Eaton et al. In: J Exp Med 200:1613-1622, 2004; Dong et al. In: J Gen Virol 84:1623-1628, 2003; Deng et al. In: Immunology 172:3437-3446, 2004; Cella et al. In: J Exp Med 184:747-752, 1996]. Starting at puberty, the involution of the thymus and the consequent reduction of the export of naïve T cells specific to neo-antigens leads to the reduction of the ratio of antigen naïve to memory cells as chronological age advances [Prelog In: Autoimmun Rev 5:136-139, 2006; McElhaney et al. In: J Immunology 176:6333-6339, 2006]. Changes in glycosylation of T cells and target antigens acquired during the aging process and the antibodies to these new glycopeptides and glycoproteins may also contribute to a reduction in the functioning of the adaptive immune response [Ishii et al. In: J Clin Neurosci 14:110-115, 2007; Shirai et al. In: Clin Exp Immunol 12:455-464, 1972; Adkins and Riley In: Mech Ageing Dev 103:147-164, 1998; Ben-Yehuda and Weksler In: Cancer Investigation 10:525-531, 1992]. One of the more interesting examples of the functional defects in the cells of the adaptive immune response is a reduced level of expression in the surface cytoadhesion and activation receptor molecules on CD4 helper T cells undergoing activation during vaccination. Upon infection or vaccination, CD40L is typically increased on the surface of CD4 helper T cells during activation, and this increased expression is absolutely essential to the CD40L promotion of expansion of antigen-specific B cells and CD 8 effector T cells in response to infection or vaccination [Singh et al. In: Protein Sci 7:1124-1135, 1998; Grewal and Flavell In: Immunol Res 16: 59-70, 1997; Kornbluth In: J Hematother Stem Cell Res 11:787-801, 2002; Garcia de Vinuesa et al. In: Eur J Immunol 29:3216-3224, 1999]. In aged human beings and mice, the reduced levels of expression of CD40 ligand (CD40L) in activated CD4 helper T cells is dramatically reduced [Eaton et al. In: J Exp Med 200:1613-1622, 2004; Dong et al. In: J Gen Virol 84:1623-1628, 2003]. To circumvent the reduction in CD40L expression and the subsequent reduction in immune response in the elderly, we have developed a chimeric vaccine comprised of the CD40L linked to the target antigen, in a replication incompetent adenoviral vector and in booster protein. This review will discuss the implementation the potential use of this approach for the vaccination of the older populations for cancer and infection.

MF59-adjuvanted versus non-adjuvanted influenza vaccines: integrated analysis from a large safety database

BACKGROUND

Adding adjuvants such as MF59((R)) to influenza vaccines can enhance the immune response. This analysis evaluated the safety profile of MF59-adjuvanted [(+)MF59] compared with non-adjuvanted [(-)MF59] vaccines in a large clinical database.

METHODS

Safety data were pooled from 64 clinical trials involving (+)MF59 seasonal and pandemic influenza vaccines. Safety outcomes were analysed in the overall population and in subjects aged > or =65 years, in all clinical trials and in controlled trials only.

FINDINGS

Data from 20,447 (+)MF59 and 7526 (-)MF59 subjects were analysed. Overall, (+)MF59 subjects had lower risks than (-)MF59 subjects of experiencing any unsolicited adverse event (AE) (26.8% vs 39.2%; adjusted risk ratio [ARR] 0.65; 95% CI 0.60-0.70), cardiovascular AEs (1.9% vs 5.6%; ARR 0.44; 95% CI 0.35-0.55), new onset chronic diseases (1.3% vs 1.9%; ARR 0.71; 95% CI 0.57-0.87) and death (0.8% vs 1.2%; ARR 0.67; 95% CI 0.51-0.87). Few AEs of potential autoimmune origin were reported: 0.71 and 0.67 per 1000 with (+)MF59 and (-)MF59, respectively. As expected, (+)MF59 subjects had a higher risk of solicited local or systemic reactions within 3 days of vaccination (58.5% vs 46.9%, weighted RR 1.34; 95% CI 1.28-1.40). Safety outcomes were consistent between total and elderly populations, and between all trials and controlled trials, although statistical significance was lost for some of the outcomes in the subgroups.

INTERPRETATION

This large-scale analysis supports the good safety profile of (+)MF59 seasonal and pandemic influenza vaccines and suggests a clinical benefit over (-)MF59 influenza vaccines.

Influenza vaccination and mortality: differentiating vaccine effects from bias

It is widely believed that influenza (flu) vaccination of the elderly reduces all-cause mortality, yet randomized trials for assessing vaccine effectiveness are not feasible and the observational research has been controversial. Efforts to differentiate vaccine effectiveness from selection bias have been problematic. The authors examined mortality before, during, and after 9 flu seasons in relation to time-varying vaccination status in an elderly California population in which 115,823 deaths occurred from 1996 to 2005, including 20,484 deaths during laboratory-defined flu seasons. Vaccine coverage averaged 63%; excess mortality when the flu virus was circulating averaged 7.8%. In analyses that omitted weeks when flu circulated, the odds ratio measuring the vaccination-mortality association increased monotonically from 0.34 early in November to 0.56 in January, 0.67 in April, and 0.76 in August. This reflects the trajectory of selection effects in the absence of flu. In analyses that included weeks with flu and adjustment for selection effects, flu season multiplied the odds ratio by 0.954. The corresponding vaccine effectiveness estimate was 4.6% (95% confidence interval: 0.7, 8.3). To differentiate vaccine effects from selection bias, the authors used logistic regression with a novel case-centered specification that may be useful in other population-based studies when the exposure-outcome association varies markedly over time.

Improving outcomes of elderly patients with community-acquired pneumonia

Community-acquired pneumonia (CAP) is a major cause of morbidity and mortality in elderly patients. Therefore, efforts to optimize the healthcare process for patients with CAP are warranted. An organized approach to management is likely to improve clinical results. Assessing the severity of CAP is crucial to predicting outcome, deciding the site of care, and selecting appropriate empirical therapy. Unfortunately, current prognostic scoring systems for CAP such as CURB-65 (confusion, uraemia, respiratory rate, low blood pressure and 65 years of age) or the Pneumonia Severity Index have not been validated specifically in older adults, in whom assessment of mortality risk alone might not be adequate for predicting outcomes. Obtaining a microbial diagnosis remains problematic and may be particularly challenging in frail elderly persons, who may have greater difficulties producing sputum. Effective empirical treatment involves selection of a regimen with a spectrum of activity that includes the causative pathogen. Although most cases of CAP are probably caused by a single pathogen, dual and multiple infections are increasingly being reported. Streptococcus pneumoniae remains the overriding aetiological agent, particularly in very elderly people. However, respiratory viruses and 'atypical' organisms such as Chlamydia pneumoniae are being described with increasing frequency in old patients, and aspiration pneumonia should also be taken into consideration, particularly in very elderly subjects and those with dementia. Age >65 years is a well established risk factor for infection with drug-resistant S. pneumoniae. Clinicians should be aware of additional risk factors for acquiring less common pathogens or antibacterial-resistant organisms that may suggest that additions or modifications to the basic empirical regimen are warranted. In addition to administration of antibacterials, appropriate supportive therapy, covering management of severe sepsis and septic shock, respiratory failure, as well as management of any decompensated underlying disease, may be critical to improving outcomes in elderly patients with CAP. Immunization with pneumococcal and influenza vaccines has also been demonstrated to be beneficial in numerous large studies. There is good evidence that implementation of guidelines leads to improvement in clinical outcomes in elderly patients with CAP, including a reduction in mortality. Protocols should address a comprehensive set of elements in the process of care and should periodically be evaluated to measure their effects on clinically relevant outcomes. Assessment of functional clinical outcome variables, in addition to survival, is strongly recommended for this population.