Effect of prior pneumococcal vaccination on clinical outcome of hospitalized adults with community-acquired pneumococcal pneumonia

Prior pneumococcal vaccination improves in-hospital mortality among elderly population hospitalized due to community-acquired pneumonia

BACKGROUND

Pneumococcal vaccination is a preventive method to reduce pneumonia related mortality. However, real-world data on efficacy of the pneumococcal vaccine in reducing mortality is lacking, especially in elderly patients. This study was conducted to assess the effects of prior pneumococcal vaccination in elderly pneumonia patients.

METHODS

The data was procured from the Health Insurance Review and Assessment and Quality Assessment database. Hospitalized patients who met the criteria of community-acquired pneumonia (CAP) were included and they were grouped according to vaccination state. Patients were aged ≥ 65 years and treated with beta-lactam, quinolone, or macrolide. Patients were excluded when treatment outcomes were unknown.

RESULTS

A total of 4515 patients were evaluated, and 1609 (35.6%) of them were vaccinated prior to hospitalization. Mean age was 77.0 [71.0;82.0], 54.2% of them were male, and mean Charlson comorbidity index (CCI) was 3.0. The patients in the vaccinated group were younger than those in the unvaccinated group (76.0 vs. 78.0 years; P < 0.001), and showed higher in-hospital improvement (97.6 vs. 95.0%; P < 0.001) and lower 30-day mortality (2.6 vs. 5.3%; P < 0.001). After adjusting confounding factors such as age, gender, CURB score and CCI score, the vaccinated group demonstrated a significant reduction in 30-day mortality (hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.41-0.81; P < 0.01) and in-hospital mortality (HR 0.53, 95% CI0.37-0.78; P < 0.001) compared to the unvaccinated group in multivariate analysis. Vaccinated group showed better 30-day survival than those in non-vaccinated group (log-rank test < 0.05).

CONCLUSIONS

Among elderly hospitalized CAP patients, prior pneumococcal vaccination was associated with improved in-hospital mortality and 30-day mortality.

COVID-19 vaccination in peritoneal dialysis patients

BACKGROUND

COVID-19 vaccine is recommended in Peritoneal dialysis (PD) patients, but a paucity of data is available regarding vaccine-related adverse effects among PD patients.

METHOD

A cross-sectional study was conducted in a single center between October and November 2021. PD patients were provided with the online survey link to participate in the study.

RESULTS

A total of 107 PD patients responded to the survey (55%: male, 79%: Chinese, 40%: > 65 years old). Of these, 95% received the COVID-19 vaccine (77% received two doses and 22% received three doses). Most participants (91%) received Pfizer vaccine. The main source of vaccine information was from the government (48%). The most common reason to receive and refuse vaccines were the perception of the seriousness of COVID-19 infection (63%) and concern about vaccine safety (60%), respectively. After the first dose, 25% of patients developed one or more vaccine-related adverse effects. Common local adverse effect was pain at the injection site (21%), and systemic adverse effects were muscle pain (15%), fatigue (13%). Similar adverse effects were observed with subsequent doses. None of them required hospitalization for vaccine-related adverse effects. Female patients had a higher risk of developing adverse effects than male patients after the first dose (odds ratio: 3.37; 95% confidence interval: 1.25 - 9.08). No such difference was observed in the subsequent dose. Age, race, employment status and history of drug allergy were not associated with the risk of adverse effects.

CONCLUSIONS

The COVID-19 vaccine was well-tolerated by most PD patients, but few experienced non-severe adverse effects. All PD patients should be vaccinated against SAR-COV-2 infection.

Pneumococcal Disease and the Effectiveness of the PPV23 Vaccine in Adults: A Two-Stage Bayesian Meta-Analysis of Observational and RCT Reports

The efficacy of PPV-23 vaccine on outcomes of pneumococcal disease in adults still remains controversial due mainly to the lack of consistency between the results obtained from observational studies(OSs) and those obtained from randomized controlled trials(RCTs). As a consequence, the complexity in the structure of evidence available, in turn, generates a challenge for combining disparate pieces of evidence quantitatively. In this regard, we used a hierarchical Bayesian inference-based evidence synthesis of RCTs and observational data using a two-stage approach (in addition to a traditional random-effects meta-analysis) to examine the effectiveness of PPV-23 in adults. To this end, 21 studies were included involving 826109 adult participants. By a two-stage Bayesian meta-analysis, which was directly used for combining studies of different designs, the overall log OR (95% credible interval) for IPDs was -0.1048 (-0.3920,-0.0250), indicating a significant protective effect of the vaccination against IPDs. No significant effect of PPV-23 was found on all-cause pneumonia, pneumococcal pneumonia, and death from pneumonia, which confirmed the results obtained by a traditional method followed by stratified and sensitivity analyses. The estimated overall log OR (95% credible interval) was -0.0002 (-0.0241,0.0142), -0.0002 (-0.0110,0.0122), and -6.3912 × 10^-5 (-0.0219,0.0131), respectively. The PPV-23 vaccine might be effective in preventing the most severe invasive forms of pneumococcal diseases, but not effective in preventing other clinical outcomes, in the adult population of 18 years and older.

Guideline for Antibiotic Use in Adults with Community-acquired Pneumonia

Community-acquired pneumonia is common and important infectious disease in adults. This work represents an update to 2009 treatment guideline for community-acquired pneumonia in Korea. The present clinical practice guideline provides revised recommendations on the appropriate diagnosis, treatment, and prevention of community-acquired pneumonia in adults aged 19 years or older, taking into account the current situation regarding community-acquired pneumonia in Korea. This guideline may help reduce the difference in the level of treatment between medical institutions and medical staff, and enable efficient treatment. It may also reduce antibiotic resistance by preventing antibiotic misuse against acute lower respiratory tract infection in Korea.

Factors associated with 30-day readmission after hospitalisation for community-acquired pneumonia in older patients: a cross-sectional study in seven Spanish regions

OBJECTIVE

Hospital readmission in patients admitted for community-acquired pneumonia (CAP) is frequent in the elderly and patients with multiple comorbidities, resulting in a clinical and economic burden. The aim of this study was to determine factors associated with 30-day readmission in patients with CAP.

DESIGN

A cross-sectional study.

SETTING

The study was conducted in patients admitted to 20 hospitals in seven Spanish regions during two influenza seasons (2013-2014 and 2014-2015).

PARTICIPANTS

We included patients aged ≥65 years admitted through the emergency department with a diagnosis compatible with CAP. Patients who died during the initial hospitalisation and those hospitalised more than 30 days were excluded. Finally, 1756 CAP cases were included and of these, 200 (11.39%) were readmitted.

MAIN OUTCOME MEASURES

30-day readmission.

RESULTS

Factors associated with 30-day readmission were living with a person aged <15 years (adjusted OR (aOR) 2.10, 95% CI 1.01 to 4.41), >3 hospital visits during the 90 previous days (aOR 1.53, 95% CI 1.01 to 2.34), chronic respiratory failure (aOR 1.74, 95% CI 1.24 to 2.45), heart failure (aOR 1.69, 95% CI 1.21 to 2.35), chronic liver disease (aOR 2.27, 95% CI 1.20 to 4.31) and discharge to home with home healthcare (aOR 5.61, 95% CI 1.70 to 18.50). No associations were found with pneumococcal or seasonal influenza vaccination in any of the three previous seasons.

CONCLUSIONS

This study shows that 11.39% of patients aged ≥65 years initially hospitalised for CAP were readmitted within 30 days after discharge. Rehospitalisation was associated with preventable and non-preventable factors.

Pneumococcal and influenza vaccination status of hospitalized adults with community acquired pneumonia and the effects of vaccination on clinical presentation

BACKGROUND

Previous reports have shown that vaccination rates of adult at-risk populations are low in Turkey. There are differing reports with regards to the effectiveness of the influenza and the pneumococcal polysaccharide vaccine (PPSV23) on the clinical outcomes of community acquired pneumonia (CAP). The purpose of this study was to analyze the influenza (FV) and pneumococcal vaccination (PV) status, the factors that influence the receipt of influenza/pneumococcal vaccine and the effects of prior vaccination on the clinical outcomes in adults hospitalized with CAP.

PATIENTS AND METHODS

Patients hospitalized with CAP between March 2009 and October 2013 and registered at the web-based Turkish Thoracic Society Pneumonia Database (TURCAP) were included in this multicentric, observational study. Of a total of 787 cases, data were analyzed for 466 patients for whom self-reported information on PV and FV was available.

RESULTS

In this adult population with CAP, the vaccination rate with both the pneumococcal and influenza vaccines was found to be 6%. Prior FV was found to be the sole variable that was associated with the receipt of PV [OR 17.8, 95% CI (25-75:8.56-37.01), p < 0.001]. Conversely, being vaccinated with PPSV23 was the only predictor of receipt of FV [OR 18.1, 95% CI (25 - 75:8.75 - 37.83), p < 0.001]. Compared to the unvaccinated cases, the chest radiograms of the vaccinated patients revealed less consolidation. The latter also reported fatigue, muscle pain and gastrointestinal symptoms less frequently. Although there was a trend for lower 30-day mortality and for lower rates of intensive care unit (ICU) admission, these did not reach statistical significance. A pneumonia severity index (PSI) score ≥ 90, CURB-65 score ≥3 and multilobar involvement, but not the vaccination status, were identified as independent determinants of ICU admission.

CONCLUSIONS

This study showed that, among patients hospitalized with CAP, the FV and/or PV rates are low. Prior vaccination does not appear to significantly affect the clinical outcomes.

Antibody repertoire profiling with mimotope arrays

Large-scale profiling and monitoring of antibody repertoires is possible through next generation sequencing (NGS), phage display libraries and microarrays. These methods can be combined in a pipeline, which ultimately maps the antibody reactivities onto defined arrays of structures - peptides or carbohydrates. The arrays can help analyze the individual specificities or can be used as complex patterns. In any case, the targets recognized should formally be considered mimotopes unless they are proven to be epitopes driving the antibody synthesis. Here, the advantages and disadvantages of the major profiling techniques as well as their current and future application in disease prediction and vaccination are discussed.

Vaccine profile of PPV23: Beijing Minhai Biotech 23-valent pneumococcal vaccine

Introduction: Diseases caused by Streptococcus pneumoniae are a major public health problem worldwide, which can be effectively prevented by the 23-valent pneumococcal polysaccharide vaccines (PPV23).Areas covered: The Beijing Minhai PPV23 showed good safety and immunogenicity profiles in clinical trials. The immunogenicity of Beijing Minhai PPV23 was non-inferior to other licensed PPVs. Although PPV23 has been proved to be highly efficient and cost-effective, and was recommended for vaccination in high-risk populations in industrialized countries, the coverage of PPV23 vaccination was relatively low in developing countries.Expert commentary: The low vaccination proportions of PPV23 in China have not been improved in recent decades. Most of the populations with indications for receiving PPV23 were not aware of the possible benefits of PPV23. Moreover, PPV23 had some limitations, which called for the development of a new generation of vaccines against pneumococcal infection.

Factors associated with pneumococcal polysaccharide vaccination of the elderly in Spain: A cross-sectional study

Vaccination of the elderly is an important factor in limiting the impact of pneumonia in the community. The aim of this study was to investigate the factors associated with pneumococcal polysaccharide vaccination in patients aged ≥ 65 years hospitalized for causes unrelated to pneumonia, acute respiratory disease, or influenza-like illness in Spain. We made a cross-sectional study during 2013-2014. A bivariate analysis was performed comparing vaccinated and unvaccinated patients, taking into account sociodemographic variables and risk medical conditions. A multivariate analysis was performed using multilevel regression models. 921 patients were included; 403 (43.8%) had received the pneumococcal vaccine (394 received the polysaccharide vaccine). Visiting the general practitioner ≥ 3 times during the last year (OR = 1.79; 95% CI 1.25-2.57); having received the influenza vaccination in the 2013-14 season (OR = 2.57; 95% CI 1.72-3.84) or in any of the 3 previous seasons (OR = 11.70; 95% CI 7.42-18.45) were associated with receiving the pneumococcal polysaccharide vaccine. Pneumococcal vaccination coverage of hospitalized elderly people is low. The elderly need to be targeted about pneumococcal vaccination and activities that encourage healthcare workers to proactively propose vaccination might be useful. Educational campaigns aimed at the elderly could also help to increase vaccination coverages and reduce the burden of pneumococcal disease in the community.

The association between antibody levels before and after 7-valent pneumococcal conjugate vaccine immunization and subsequent pneumococcal infection in chronic arthritis patients

INTRODUCTION

The aim of present study is to inverstigate the association between antibody levels after vaccination with 7-valent pneumococcal conjugate vaccine (PCV7) and subsequent serious pneumococcal infections in rheumatoid arthritis (RA) and spondylarthropathy (SpA) patients.

METHODS

A cohort of 497 patients (RA=248 and SpA=249) received a single dose of PCV7. At vaccination, patients were treated with methotrexate (MTX; n=85), anti-tumour necrosis factor (anti-TNF) + MTX (n=169), anti-TNF monotherapy (n=158) and non-steroidal anti-inflammatory drugs (NSAIDs)/analgesics (n=85). Antibody levels of serotypes 6B and 23B were analyzed before and 4 to 6 weeks after vaccination using standard enzyme-linked immunosorbent assay (ELISA). Serious pneumococcal infections (pneumonia/lower respiratory tract infection, meningitis, sepsis, septic arthritis) occurring within 4.5 years after vaccination were identified in the Skåne Healthcare Register using the International Classification of Diseases, tenth revision (ICD-10) codes. The association between post-vaccination antibody levels and protection against infections and determination of protective cutoff levels was explored using receiver operating characteristic (ROC) curves. Predictors of infection were studied using regression analyses.

RESULTS

Eighteen infections were registered in 15 patients before vaccination and 27 infections in 23 patients after vaccination. Patients with serious infections after vaccination had significantly lower post-vaccination antibody titres for both 6B (P=0.04) and 23 F (P=0.04). Post-vaccination antibody levels of at least 1.29 mg/L and 1.01 mg/L for 6B and 23, respectively, were associated with better protection from serious infections. Higher age, concomitant prednisolone but not MTX or anti-TNF were associated with such infections.

CONCLUSIONS

Patients with more robust antibody responses after vaccination with pneumococcal conjugate vaccine were less likely to suffer from serious infections. High age and prednisolone at vaccination were associated with putative serious pneumococcal infections in this cohort.

TRIAL REGISTRATION NUMBER

EudraCT EU 2007-006539-29 and NCT00828997 . Registered 23 January 2009.

Prior pneumococcal and influenza vaccinations and in-hospital outcomes for community-acquired pneumonia in elderly veterans

BACKGROUND

Studies of adults hospitalized for community-acquired pneumonia (CAP) reported better outcomes associated with prior pneumococcal vaccination (PV), suggesting potential additional benefits of PV in hospitalized CAP patients. Influenza (flu) vaccination (FV) could independently/additively improve CAP outcomes in hospitalized patients.

OBJECTIVE

To examine the effect of prior PV and FV on in-hospital outcomes in elderly veterans hospitalized for CAP.

DESIGN

Retrospective cohort study.

SETTING AND PATIENTS

A total of 6,723 elderly veterans who were admitted to Veterans Affairs hospitals for CAP between October 1, 2002 and September 30, 2003.

INTERVENTION

PV in the 5 years and FV in the 1 year before admission.

MEASUREMENTS

The association of prior PV and/or FV with inpatient mortality and length of stay (LOS) (primary) and risk of any bacteremia and respiratory complications (secondary) were assessed using logistic regressions and generalized linear model, controlling for patient demographic and clinical characteristics.

RESULTS

Prior PV alone was not associated with shortened LOS, or reduced risk of inpatient mortality or respiratory complications. Lower risk of bacteremia was associated with prior PV (odds ratio: 0.66; 95% confidence interval [CI]: 0.48-0.90). After adjusting for patients' characteristics, risk of inpatient mortality was not statistically significantly different across the vaccination groups, but having had both PV and FV before CAP admission was associated with a 10% reduction in LOS (95% CI: 0.86-0.95) compared to having had neither vaccinations.

CONCLUSION

Significant survival benefit and improved in-hospital outcomes may not be expected among CAP-hospitalized elderly patients with prior PV alone. However, having both PV and FV before CAP admission may reduce LOS.

Clinical features, etiology and outcomes of community-acquired pneumonia in patients with chronic obstructive pulmonary disease

BACKGROUND

Community-acquired pneumonia (CAP) is a frequent complication of chronic obstructive pulmonary disease (COPD), but previous studies are often contradictory.

OBJECTIVES

We aimed to ascertain the characteristics and outcomes of CAP in patients with COPD as well as to determine the risk factors for mortality and Pseudomonas aeruginosa pneumonia in COPD patients with CAP. We also describe the etiology and outcomes of CAP in COPD patients receiving chronic oxygen therapy at home and those receiving inhaled steroids.

METHODS

An observational analysis of a prospective cohort of hospitalized adults with CAP (1995-2011) was performed.

RESULTS

We documented 4121 CAP episodes, of which 983 (23.9%) occurred in patients with COPD; the median FEV1 value was 50%, and 57.8% were classified as stage III or IV in the GOLD classification. Fifty-eight per cent of patients were receiving inhaled steroids, and 14.6% chronic oxygen therapy at home. Patients with COPD presented specific clinical features. S. pneumoniae was the leading causative organism overall, but P. aeruginosa was more frequent in COPD (3.4 vs. 0.5%; p<0.001). Independent risk factors for case-fatality rate in patients with COPD were multilobar pneumonia, P. aeruginosa pneumonia, and high-risk PSI classes. Prior pneumococcal vaccination was found to be protective. FEV1 was an independent risk factor for P. aeruginosa pneumonia.

CONCLUSIONS

CAP in patients with COPD presents specific characteristics and risk factors for mortality. Prior pneumococcal vaccine has a beneficial effect on outcomes. P. aeruginosa pneumonia is associated with low FEV1 values and poor prognosis.

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.

A cross-sectional study to investigate pneumococcal vaccination in the elderly in a low income county: patient knowledge, awareness, and attitudes of vaccination and prevalence rates by socioeconomic status

BACKGROUND

Pneumonia represents the leading cause of infection-related death and the fifth cause of overall mortality, in the elderly. With increasing age, the human immune system undergoes characteristic changes which lead to increased incidence and severity of infectious diseases and to insufficient protection following vaccination as antibody response of elderly vaccines are weaker and decline faster.

OBJECTIVE

Knowledge and Attitude toward Pneumonia and its Vaccination in elderly patients.

RESULT

Among low SES, 54.9% (549/1000) while from high SES, 91.8% (918) responded that they had heard about pneumonia before (P<0.05). 79.5% (795/1000) patients of high SES had heard about pneumococcal vaccination while only 28.8% (288/1000) patients from low SES had heard about pneumococcal vaccine. Only 2.3% of low SES patients were immunized for pneumococcal vaccine while 16.5% high SES patients were vaccinated. Reported reason for not being immunized were; did not hear, no body advised, vaccine is too expensive, and ignored thinking it is not necessary.

METHOD

We conducted a cross-sectional study on 2000 elderly patients who were admitted in medicine and surgery wards of Civil Hospital Karachi and Aga Khan University Hospital Karachi from the period of October to December 2012 to determine their knowledge and attitude toward pneumonia and its vaccination in elderly. Study group was divided into low and high socio-economic status on the basis of patients coming to government Hospital i.e., civil hospital and private hospital i.e., Aga khan hospital. Data was collected through convenient sampling technique. Exclusion criteria were patients below 60 years and those who didn't give consent to be part of study.

CONCLUSION

Aside from introducing public awareness program about elderly vaccination at state level, free of cost vaccination of elderly individuals should be done.

Preventing pneumococcal disease in the elderly: recent advances in vaccines and implications for clinical practice

Streptococcus pneumoniae remains a major cause of morbidity and mortality throughout the world. To date, after the introduction of routine childhood immunization, elderly people (i.e., persons aged 65 years or older) suffer the greatest burden of pneumococcal disease in developed countries. At present, two anti-pneumococcal vaccines are available for use in adults: the 23-valent pneumococcal polysaccharide vaccine (PPV23) and the 13-valent protein-polysaccharide conjugate vaccine (PCV13). This article reviews current data about the burden of pneumococcal disease in the elderly, as well as evidence for immunogenicity, clinical efficacy, and possible cost-effectiveness of both vaccines. The main advantage of PCV13 is that it may be more effective than PPV23, but a major limitation is that it is directed against strains that are likely to be greatly reduced in the population since its introduction in childhood immunization. The main disadvantage of PPV23 is that it may be less effective than PCV13 against vaccine-type infections but a major advantage is that it may provide protection against ten additional serotypes. To date, expert committees have not changed recommendations for pneumococcal vaccination in adults. However, at present, they are evaluating different alternatives (basically, maintaining PPV23, changing from PPV23 to PCV13 in some groups, or adding PCV13 for all or some target adult population subgroups). Critical data (clinical efficacy reported in ongoing trials and magnitude of indirect effects of pediatric PCV13 programs) needed to make a well-informed decision could be available during 2013. Considering all concerns over indirect effects and replacement strains following the use of polysaccharide-based vaccines, efforts should be directed toward developing vaccines, such as protein-based pneumococcal vaccines, with potential serotype-independent protection. Meanwhile, according to current recommendations, PPV23 should continue to be used for high-risk adults and all elderly people (with and without additional high-risk conditions). Although it is only moderately effective, it has a considerable serotype coverage and at-risk persons can benefit from the vaccination. High-risk individuals could also obtain a benefit from adding PCV13, but more data are needed before a universal recommendation can be made.

Outpatient-based pneumococcal vaccine campaign and survey of perceptions about pneumococcal vaccination in patients and doctors

PURPOSE

Despite the ready availability of pneumococcal vaccine, vaccination rates are quite low in South Korea. This study was designed to assess perceptions and awareness about pneumococcal vaccines among subjects at risk and find strategies to increases vaccine coverage rates.

MATERIALS AND METHODS

A cross sectional, community-based survey was conducted to assess perceptions about the pneumococcal vaccine at a local public health center. In a tertiary hospital, an outpatient- based pneumococcal vaccine campaign was carried out for the elderly and individuals with chronic co-morbidities from May to July of 2007.

RESULTS

Based on the survey, only 7.6% were ever informed about pneumococcal vaccination. The coverage rates of the pneumococcal vaccine before and after the hospital campaign showed an increased annual rate from 3.39% to 5.91%. The most common reason for vaccination was "doctor's advice" (53.3%). As for the reasons for not receiving vaccination, about 75% of high risk patients were not aware of the pneumococcal vaccine, which was the most important barrier to vaccination. Negative clinician's attitude was the second most common cause of non-vaccination.

CONCLUSION

Annual outpatient-based campaigns early in the influenza season may improve pneumococcal vaccine coverage rates. Doctor's advice was the most important encouraging factor for vaccination.

Vaccines for preventing pneumococcal infection in adults

BACKGROUND

Diseases caused by Streptococcus pneumoniae (S. pneumoniae) continue to cause substantial morbidity and mortality globally. Whilst pneumococcal polysaccharide vaccines (PPVs) have the potential to prevent disease and death, the degree of protection afforded against various clinical endpoints and within different populations is uncertain.

OBJECTIVES

To assess the efficacy and effectiveness of PPVs in preventing pneumococcal disease or death in adults. We did not assess adverse events.

SEARCH METHODS

We searched CENTRAL 2012, Issue 6, MEDLINE (January 1966 to June Week 2, 2012) and EMBASE (1974 to June 2012).

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) in adults, provided the study outcome met the definition of the outcome considered in the review. We also considered non-RCTs in adults, where the study assessed PPV effectiveness against culture-confirmed invasive pneumococcal disease (IPD), provided the study controlled for important confounding factors.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trial quality of RCTs and three review authors extracted the data. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) using a random-effects model. Two review authors assessed study quality and extracted data for non-RCTs. We calculated ORs and 95% CIs using a random-effects model following the conversion of each study outcome to a log OR and standard error (SE).

MAIN RESULTS

Twenty-five studies met our inclusion criteria (18 RCTs involving 64,852 participants and seven non-RCTs involving 62,294 participants). Meta-analysis of the RCTs found strong evidence of PPV efficacy against IPD with no statistical heterogeneity (OR 0.26, 95% CI 0.14 to 0.45; random-effects model, I(2) statistic = 0%). There was efficacy against all-cause pneumonia in low-income (OR 0.54, 95% CI 0.43 to 0.67, I(2) statistic = 19%) but not high-income countries in either the general population (OR 0.71, 95% CI 0.45 to 1.12, I(2) statistic = 93%) or in adults with chronic illness (OR 0.93, 95% CI 0.73 to 1.19, I(2) statistic = 10%). PPV was not associated with substantial reductions in all-cause mortality (OR 0.90, 95% CI 0.74 to 1.09; random-effects model, I(2) statistic = 69%). Vaccine efficacy against primary outcomes appeared poorer in adults with chronic illness. Non-RCTs provided evidence for protection against IPD in populations for whom the vaccine is currently utilised (OR 0.48, 95% CI 0.37 to 0.61; random-effects model, I(2) statistic = 31%). This review did not consider adverse events as it was outside the scope of the review.

AUTHORS' CONCLUSIONS

This meta-analysis provides evidence supporting the recommendation for PPV to prevent IPD in adults. The evidence from RCTs is less clear with respect to adults with chronic illness. This might be because of lack of effect or lack of power in the studies. The meta-analysis does not provide evidence to support the routine use of PPV to prevent all-cause pneumonia or mortality.

Clinical features, etiology, and outcomes of community-acquired pneumonia in patients with diabetes mellitus

We performed an observational analysis of a prospective cohort of immunocompetent hospitalized adults with community-acquired pneumonia (CAP) to determine the epidemiology, clinical features, and outcomes of pneumonia in patients with diabetes mellitus (DM). We also analyzed the risk factors for mortality and the impact of statins and other cardiovascular drugs on outcomes. Of 2407 CAP episodes, 516 (21.4%) occurred in patients with DM; 483 (97%) had type 2 diabetes, 197 (40%) were on insulin treatment, and 119 (23.9%) had end-organ damage related to DM. Patients with DM had different clinical features compared to the other patients. They were less likely to have acute onset, cough, purulent sputum, and pleural chest pain. No differences in etiology were found between study groups. Patients with DM had more inhospital acute metabolic complications, although the case-fatality rate was similar between the groups. Independent risk factors for mortality in patients with DM were advanced age, bacteremia, septic shock, and gram-negative pneumonia. Patients with end-organ damage related to DM had more inhospital cardiac events and a higher early case-fatality rate than did the overall population. The use of statins and other cardiovascular drugs was not associated with better CAP outcomes in patients with DM. In conclusion, CAP in patients with DM presents different clinical features compared to the features of patients without DM.

[Multidisciplinary guidelines for the management of community-acquired pneumonia]

Community-acquired pneumonia (CAP) is an infectious respiratory disease with an incidence that ranges from 3 to 8 cases per 1,000 inhabitants per year. This incidence increases with age and comorbidities. Forty per cent of CAP patients require hospitalization and around 10% of these patients are admitted in an Intensive Care Unit (ICU). Several studies have suggested that the implementation of clinical guidelines has a positive impact in the outcome of patients including mortality and length of stay. The more recent and used guidelines are those from Infectious Diseases Society of America/American Thoracic Society, published in 2007, the 2009 from the British Thoracic Society, and that from the European Respiratory Society/European Society of Clinical Microbiology and Infectious Diseases, published in 2010. In Spain, the most recently released guideline is the Sociedad Española de Neumología y Cirugía Torácica-2011 guideline. The present guidelines GNAC are designed to be used by the majority of health-care professionals that can participate in the care of CAP patients including diagnosis, decision of hospital and ICU admission, treatment and prevention. The Centro Cochrane Iberoamericano (CCIB) has participated in summarizing the previous guidelines and in the bibliography search. For each one of the following sections the panel of experts has developed a table with recommendations classified according to its evidence, strength and practical applicability using the Grading of Recommendations of Assessment Development and Evaluations (GRADE) system: 1. Epidemiology, microbiological etiology and antibiotic resistances.2. Clinical and microbiological diagnosis.3. Prognostic scales and decision of hospital admission.4. ICU admission criteria. 5. Empirical and definitive antibiotic treatment.6. Treatment failure. 7. Prevention.

[Severe pneumococcal infections in the elderly - preventable by vaccination]

Elderly people are more susceptible to pneumococcal infections. Data in Germany from 2005-2010 shows that especially seniors are prone to develop serious complications such as sepsis. Women are obviously less affected than men. Most of the infections occurred during the winter months. The majority of isolates, i.e., about 80%, possess capsular polysaccharide antigens which are represented in the 23-valent vaccine. Consequently, it could be assumed that the severe complications ensuing long hospital stays and associated with a high mortality could have been avoided, if the elderly people would have been vaccinated, which, however, was only true in a small proportion (28%). Recently, a new conjugated vaccine was introduced to the market. In principle, several antibiotics are available for direct antibacterial treatment. All isolates are susceptible to cefotaxime as well as to ceftriaxone. Resistance to penicillin as well as ampicillin is very rare in Germany. The vast majority of isolates are susceptible to quinolones such as levofloxacin and moxifloxacin. Resistance to macrolides, for example to erythromycin, occurs to a certain extent but the percentage has been declining in recent years. Nevertheless, in many instances therapy is too late. Thus, prevention is of great importance.

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.

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.

Pneumonia complicating pandemic (H1N1) 2009: risk factors, clinical features, and outcomes

We performed an observational analysis of a prospective cohort of adults hospitalized for pandemic (H1N1) 2009 at 13 Spanish hospitals, from June to November 2009, to determine the risk factors, clinical features, and outcomes of pneumonia. Of 585 patients requiring hospitalization, chest radiography was obtained in 542. A total of 234 (43.1%) patients had pneumonia, of whom 210 underwent bacterial microbiologic studies. Of these patients, 174 (82.8%) had primary viral pneumonia and 36 (17.2%) had concomitant/secondary bacterial pneumonia. Bilateral pneumonia occurred in 48.3% of patients. Streptococcus pneumoniae was the most frequent pathogen among patients with bacterial pneumonia (26 of 36 patients). None of them had received pneumococcal vaccine. Compared with patients without pneumonia, those with pneumonia more frequently had shock during hospitalization (9.8% vs. 1%; p < 0.001), required intensive care unit admission (22.6% vs. 5.8%; p < 0.001), underwent mechanical ventilation (17.9% vs. 3.2%; p < 0.001), and had longer length of hospital stay (median, 7 d vs. 5 d; p < 0.001). In-hospital mortality was higher in patients with pneumonia than in the others (5.2% vs. 0%; p < 0.001). Absence of comorbid conditions (odds ratio [OR], 2.07; 95% confidence interval [CI], 1.32-3.24) was found to be an independent risk factor for pneumonia, whereas early (≤ 48 h) oseltamivir therapy (OR, 0.29; 95% CI, 0.19-0.46) was a protective factor. In conclusion, pneumonia is a frequent complication among adults hospitalized for pandemic (H1N1) 2009 and causes significant morbidity. Mortality in pandemic (H1N1) 2009 is low, but occurs mainly in patients with pneumonia. Early oseltamivir therapy is a protective factor for this complication.

Influence of prior pneumococcal and influenza vaccination on outcomes of older adults with community-acquired pneumonia

OBJECTIVES

To determine whether prior pneumococcal and seasonal influenza vaccination improves outcomes in older adults hospitalized for community-acquired pneumonia (CAP).

DESIGN

Prospective, observational, multicenter study.

SETTING

Five public hospitals providing universal free care to the whole population in three Spanish regions.

PARTICIPANTS

Individuals aged 65 and older admitted to the hospital with CAP through the emergency department.

MEASUREMENTS

Pneumococcal and influenza vaccination status. The primary study outcomes were intensive care unit (ICU) admission, length of hospital stay (LOS), and overall case-fatality rate. Outcome variables of individuals vaccinated with both vaccines were compared with outcomes of those who were unvaccinated.

RESULTS

Two hundred thirty-eight individuals had received 23-valent pneumococcal polysaccharide vaccine and seasonal influenza vaccination and were compared with 195 unvaccinated individuals. No differences were found with respect to combined antibiotic therapy between groups (38.0% vs 39.7%; P = .80). Similar percentages of vaccinated and unvaccinated individuals required ICU admission (7.2% vs 8.2%; P = .69). Mean LOS was significantly shorter in vaccinated individuals (9.9 vs 12.4 days; P = .04). Overall case-fatality rates were similar in both groups (5.9% vs 5.1%; P = .73). After adjustment, LOS, risk of ICU admission, and overall case-fatality rate were not associated with prior pneumococcal and seasonal influenza vaccination.

CONCLUSION

The clinical outcomes of vaccinated older adults hospitalized with CAP were not better than those observed in unvaccinated individuals.

Community-acquired pneumonia in patients with liver cirrhosis: clinical features, outcomes, and usefulness of severity scores

We performed an observational analysis of a prospective cohort of nonimmunocompromised hospitalized adults with community-acquired pneumonia (CAP) to determine the epidemiology, clinical features, and outcomes of patients with liver cirrhosis. We also analyzed the prognostic value of several severity scores. Of 3420 CAP episodes, 90 occurred in patients with liver cirrhosis. The median value of the Model for End-Stage Liver Disease (MELD) was 14 (range, 6-36). On the Child-Pugh (CP) score, 56% of patients were defined as grade B and 22% as grade C. Patients with liver cirrhosis were younger (61.8 vs. 66.8 yr; p = 0.001) than patients without cirrhosis, more frequently presented impaired consciousness at admission (33% vs. 14%; p < 0.001) and septic shock (13% vs. 6%; p = 0.011), and were more commonly classified in high-risk Pneumonia Severity Index (PSI) classes (classes IV-V) (74% vs. 58%; p = 0.002). Streptococcus pneumoniae (47% vs. 33%; p = 0.009) and Pseudomonas aeruginosa (4.4% vs. 0.9%; p = 0.001) were more frequently documented in patients with cirrhosis. Bacteremia was also more common in these patients (22% vs. 13%; p = 0.023). Areas under the curve (AUCs) from disease-specific scores (MELD, CP, PSI, and CURB-65 [confusion, urea, respiratory rate, blood pressure, and age ≥65 yr]) were comparable in predicting severe disease (30-d mortality and intensive care unit [ICU] admission). A new score based on MELD, multilobar pneumonia, and septic shock at admission (MELD-CAP) had an AUC of 0.945 (95% confidence interval [CI], 0.872-0.983) for predicting severe disease and was significantly different from other scores. Early (5.6% vs. 2.1%; p = 0.048) and overall (14.4% vs. 7.4%; p < 0.024) mortality rates were higher in cirrhotic patients than in patients without cirrhosis. Factors associated with mortality were impaired consciousness, multilobar pneumonia, ascites, acute renal failure, bacteremia, ICU admission, and MELD score. Among the severity scores, MELD-CAP was the only score associated with severe disease (odds ratio [OR], 1.33; 95% CI, 1.09-1.52) and mortality (OR, 1.21; 95% CI, 1.03-1.42). In conclusion, CAP in patients with liver cirrhosis presents a distinctive clinical picture and is associated with higher mortality than is found in patients without cirrhosis. The severity of hepatic dysfunction plays an important role in the development of adverse events. Cirrhosis-specific scores may be useful for predicting and stratifying cirrhotic patients with CAP who have a high risk of severe disease.

Epidemiology, clinical features and outcomes of pneumonia in patients with chronic kidney disease

BACKGROUND

Although infection remains among the most common causes of morbidity and mortality in patients with chronic kidney disease (CKD), data on epidemiology, clinical features and outcomes of pneumonia in this population are scarce.

METHODS

Observational analysis of a prospective cohort of hospitalized adults with pneumonia, between 13 February 1995 and 30 April 2010, in a tertiary teaching hospital. CKD patients, defined as patients with a baseline glomerular filtration rate <60 mL/min/1.73 m(2), were compared with non-CKD patients.

RESULTS

During the study period, 3800 patients with pneumonia required hospitalization. Two-hundred and three (5.3%) patients had CKD, of whom 46 were on dialysis therapy. Patients with CKD were older (77 versus 70 years; P < 0.001), were more likely to have comorbidities (82.3 versus 63.3%; P < 0.001) and more commonly classified into high-risk pneumonia severity index classes (89.6 versus 57%; P < 0.001) than were the remaining patients. Streptococcus pneumoniae was the most frequent pathogen (28.1 versus 34.7%; P = 0.05). Mortality was higher in patients with CKD (15.8 versus 8.3%; P < 0.001). Among CKD patients, age [+1 year increase; adjusted odds ratio, 1.25; 95% confidence interval (CI) 1.07-1.46] and cardiac complications during hospitalization (adjusted odds ratio, 9.23; 95% CI 1.39-61.1) were found to be independent risk factors for mortality, whereas prior pneumococcal vaccination (adjusted odds ratio, 0.05; 95% CI 0.005-0.69) and leukocytosis at hospital admission (adjusted odds ratio, 0.10; 95% CI 0.01-0.64) were protective factors.

CONCLUSIONS

Pneumonia is a serious complication in CKD patients. Independent factors for mortality are older age and cardiac complications, whereas prior pneumococcal vaccination and leucokytosis at hospital admission are protective factors. These findings should encourage physicians to increase pneumococcal vaccine coverage among CKD patients.

Characterization of gene use and efficacy of mouse monoclonal antibodies to Streptococcus pneumoniae serotype 8

Streptococcus pneumoniae is the most common cause of community-acquired pneumonia in the United States and globally. Despite the availability of pneumococcal capsular polysaccharide (PPS) and protein conjugate-based vaccines, the prevalence of antibiotic-resistant pneumococcal strains, serotype (ST) replacement in nonconjugate vaccine strains, and uncertainty as to whether the PPS vaccine that is used in adults protects against pneumonia emphasize the need for continued efforts to understand the nature of protective PPS antibody responses. In this study, we generated mouse monoclonal antibodies (MAbs) to a conjugate consisting of the PPS of serotype 8 (PPS8) S. pneumoniae and tetanus toxoid. Thirteen MAbs, including four IgMs that bound to PPS8 and phosphorylcholine (PC) and five IgMs and four IgG1s that bound to PPS8 but not PC, were produced, and their nucleotide sequences, epitope and fine specificity, and efficacy against lethal challenge with ST8 S. pneumoniae were determined. MAbs that bound to PPS8 exhibited gene use that was distinct from that exhibited by MAbs that bound to PC. Only PPS8-binding MAbs that did not bind PC were protective in mice. All 13 MAbs used germ line variable-region heavy (V(H)) and light (V(L)) chain genes, with no evidence of somatic hypermutation. Our data reveal a relationship between PPS specificity and V(H) gene use and MAb efficacy in mice. These findings provide insight into the relationship between antibody molecular structure and function and hold promise for the development of novel surrogates for pneumococcal vaccine efficacy.

Predictors of inhospital mortality and re-hospitalization in older adults with community-acquired pneumonia: a prospective cohort study

BACKGROUND

A better understanding of potentially modifiable predictors of in-hospital mortality and re-admission to the hospital following discharge may help to improve management of community-acquired pneumonia in older adults. We aimed to assess the associations of potentially modifiable factors with mortality and re-hospitalization in older adults hospitalized with community-acquired pneumonia.

METHODS

A prospective cohort study was conducted from July 2003 to April 2005 in two Canadian cities. Patients aged 65 years or older hospitalized for community-acquired pneumonia were followed up for up to 30 days from initial hospitalization for mortality and these patients who were discharged alive within 30 days of initial hospitalization were followed up to 90 days of initial hospitalization for re-hospitalization. Separate logistic regression analyses were performed identify the predictors of mortality and re-hospitalization.

RESULTS

Of 717 enrolled patients hospitalized for community-acquired pneumonia, 49 (6.8%) died within 30 days of hospital admission. Among these patients, 526 were discharged alive within 30 days of hospitalization of whom 58 (11.2%) were re-hospitalized within 90 days of initial hospitalization. History of hip fracture (odds ratio (OR) = 4.00, 95% confidence interval (CI) = (1.46, 10.96), P = .007), chronic obstructive pulmonary disease (OR = 2.31, 95% CI = (1.18, 4.50), P = .014), cerebrovascular disease (OR = 2.11, 95% CI = (1.03, 4.31), P = .040) were associated with mortality. Male sex (OR = 2.35, 95% CI = (1.13, 4.85), P = .022) was associated with re-hospitalization while vitamin E supplementation was protective (OR = 0.37 (0.16, 0.90), P = .028). Lower socioeconomic status, prior influenza and pneumococcal vaccinations, appropriate antibiotic prescription upon admission, and lower nutrition risk were not significantly associated with mortality or re-hospitalization.

CONCLUSION

Chronic comorbidities appear to be the most important predictors of death and re-hospitalization in older adults hospitalized with community-acquired pneumonia while vitamin E supplementation was protective.

Aetiology of, and risk factors for, recurrent community-acquired pneumonia

Recurrent community-acquired pneumonia (CAP) requiring hospitalization is a matter of particular concern. However, current information on its prevalence, aetiology and risk factors is lacking. To address these issues, we performed an observational analysis of a prospective cohort of hospitalized adults with CAP. Recurrence was defined as two or more episodes of CAP 1 month apart within 3 years. Patients with severe immunosuppression or local predisposing factors were excluded. Of the 1556 patients, 146 (9.4%) had recurrent CAP. The most frequent causative organism was Streptococcus pneumoniae, both in patients with recurrent CAP and in those without recurrence. Haemophilus influenzae, other Gram-negative bacilli and aspiration pneumonia were more frequent among patients with recurrent CAP, whereas Legionella pneumophila was rarely identified in this group. Independent factors associated with recurrent CAP were greater age, lack of pneumococcal vaccination, chronic obstructive pulmonary disease (COPD) and corticosteroid therapy. In a sub-analysis of 389 episodes of pneumococcal pneumonia, the only independent risk factor for recurrence was lack of pneumococcal vaccination. Recurrence of CAP is not a rare clinical problem and it occurs mainly in the elderly, patients with COPD, and those receiving corticosteroids. Our study provides support for recommending pneumococcal vaccination for adults at risk of pneumonia, including those with a first episode of CAP.

Impact of prior pneumococcal vaccination on clinical outcomes in HIV-infected adult patients hospitalized with invasive pneumococcal disease

BACKGROUND

Recent studies in hospitalized patients with community-acquired pneumonia have found a lower risk of bacteraemia and better clinical outcomes in patients who had previously received the 23-valent pneumococcal polysaccharide vaccine (PPV) in comparison with unvaccinated individuals. The aim of this study was to assess the influence of prior PPV on clinical outcomes in HIV-infected adult patients hospitalized with invasive pneumococcal disease (IPD).

METHODS

This was an observational study of all consecutive HIV-infected adults hospitalized with IPD from January 1996 to October 2007 in three hospitals in Spain. Baseline characteristics and clinical outcome-related variables were compared according to prior PPV vaccination status.

RESULTS

A total of 162 episodes of IPD were studied. In 23 of these (14.2%), patients had previously received PPV. In both vaccinated and unvaccinated patients, most of the causal serotypes were included in the 23-valent PPV (76.9% and 84.1%, respectively). Overall, 25 patients (15.4%) died during hospitalization, 21 patients (13%) required admission to an intensive care unit (ICU) and 34 patients (21%) reached the composite outcome of death and/or admission to the ICU. None of the 23 patients who had previously received PPV died or required ICU admission, in comparison with 25 (18%; P=0.026) and 21 (15.1%; P=0.046), respectively, of the unvaccinated patients. The length of hospital stay for vaccinated patients was significantly shorter (8.48 vs. 13.27 days; P=0.011).

CONCLUSIONS

Although 23-valent PPV failed to prevent IPD in some HIV-infected patients, vaccination produced beneficial effects on clinical outcomes by decreasing illness severity and mortality related to IPD.

Anti-platelet drugs and outcome in severe infection: clinical impact and underlying mechanisms

Platelet activation contributes to microvascular thrombosis and organ failure in systemic inflammation. We tested the hypothesis whether anti-platelet drugs might favourably affect outcome in patients at risk for organ failure as well as in a mouse model of endotoxin shock. Two hundred twenty-four consecutive patients who were admitted for community acquired pneumonia over a time period of 5 years to a University Hospital were enrolled; about 20% of whom received anti-platelet drugs (acetylsalicylic acid, thienopyridines) for secondary prevention of cardiovascular disease. Patients with anti-platelet drugs were about 12 years old but did not differ in SOFA score and routine laboratory parameters at admission. Logistic regression and 2 x 2 table analysis in age-matched subgroups indicated that anti-platelet drugs may reduce the need of intensive care treatment (odds ratio (OR) 0.32 [95% confidential interval: 0.10-1.00] and 0.19 [0.04-0.87], respectively). In age-matched subgroups, the use of anti-platelet drugs was also associated with a shorter stay in hospital (13.9 +/- 6.2 vs. 18.2 +/- 10.2 days; p < 0.02). In the animal model Balb/c mice were pre-treated with clopidogrel (added to drinking water) for 4 days prior to intraperitoneal (i.p.) administration of endotoxin (lipopolsaccharide (LPS) from Escherichia coli 0111:B4). Within the first 48 hours after LPS there were no differences between clopidogrel and control animals (n = 26 each) in macro-haemodynamics. However, clopidogrel abolished the LPS-induced drop in platelet count and reduced fibrin deposition in lung tissue. Using DNA microarray technology, we could show that clopidogrel suppressed endotoxin-induced up-regulation of inflammation-relevant genes, including arachidonate-5-lipoxygenase activating protein and leukotriene B4 receptor 1. According to our data a possible benefit of anti-platelet drugs in patients on risk for systemic inflammation and organ failure should be tested in a prospective trial.

Efficacy of opsonic and nonopsonic serotype 3 pneumococcal capsular polysaccharide-specific monoclonal antibodies against intranasal challenge with Streptococcus pneumoniae in mice

Serotype-specific antibodies to pneumococcal capsular polysaccharide (PPS) are a critical component of vaccine-mediated immunity to Streptococcus pneumoniae. In this study, we investigated the in vitro opsonophagocytic activities of three PPS-specific mouse immunoglobulin G1 monoclonal antibodies (MAbs), 1E2, 5F6, and 7A9, and determined their in vivo efficacies against intranasal challenge with WU2, a serotype 3 pneumococcal strain, in normal and immunodeficient mice. The MAbs had different in vitro activities in a pneumococcal killing assay: 7A9 enhanced killing by mouse neutrophils and J774 cells in the presence of a complement source, whereas 5F6 promoted killing in the absence, but not the presence, of complement, and 1E2 did not promote killing under any conditions. Nonetheless, all three MAbs protected normal and complement component 3-deficient mice from a lethal intranasal challenge with WU2 in passive-immunization experiments in which 10 mug of the MAbs were administered intraperitoneally before intranasal challenge. In contrast, only 1E2 protected Fcgamma receptor IIB knockout (FcgammaRIIB KO) mice and mice that were depleted of neutrophils with the MAb RB6, whereas 7A9 and 5F6 required neutrophils and FcgammaRIIB to mediate protection. Conversely, 7A9 and 5F6 protected FcgammaR KO mice, but 1E2 did not. Hence, the efficacy of 1E2 required an activating FcgammaR(s), whereas 5F6 and 7A9 required the inhibitory FcgammaR (FcgammaRIIB). Taken together, our data demonstrate that both MAbs that do and do not promote pneumococcal killing in vitro can mediate protection in vivo, although their efficacies depend on different host receptors and/or components.

Effectiveness of pneumococcal vaccination in older adults with chronic respiratory diseases: results of the EVAN-65 study

A prospective cohort study evaluating the clinical effectiveness of the 23-valent pneumococcal polysaccharide vaccine was conducted among 1298 Spanish older adults with chronic respiratory diseases (bronchitis, emphysema or asthma) who were followed between 2002 and 2005. Main outcomes were all-cause community-acquired pneumonia (CAP) and 30 days mortality from CAP. The association between vaccination and the risk of each outcome was evaluated by multivariable Cox proportional-hazard models adjusted for age and comorbidity pneumococcal vaccination did not alter significantly the risk of overall CAP (hazard ratio [HR]: 0.77; 95% confidence interval [CI]: 0.56-1.07) and 30 days mortality from CAP (HR: 0.87; 95% CI: 0.33-2.28). However, a borderline significant reduction of 30% in the risk of all-cause hospitalisation for CAP was observed among vaccinated subjects (HR: 0.70; 95% CI: 0.48-1.00; p=0.052). The effectiveness of the vaccine on the combined endpoint of pneumococcal and unknown organism infections reached 34% (HR: 0.66; 95% CI: 0.43-1.01; p=0.059). Although our findings suggest moderate benefits from the vaccination, the evidence of clinical effectiveness appears limited.

Vaccines for preventing pneumococcal infection in adults

BACKGROUND

Diseases caused by Streptococcus pneumoniae(S. pneumoniae) continue to cause substantial morbidity and mortality throughout the world. Whilst pneumococcal polysaccharide vaccines (PPV) have the potential to prevent disease and death, the degree of protection afforded against various clinical endpoints and within different populations is uncertain.

OBJECTIVES

To assess the effectiveness of PPV in preventing disease or death in adults. Adverse events were not assessed.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2007, Issue 2); MEDLINE (January 1966 to June 2007); and EMBASE (1974 to June 2007).

SELECTION CRITERIA

A) Randomised controlled trials (RCTs) comparing PPV with placebo, control vaccines, or no intervention.B) Non-RCTs assessing PPV effectiveness against invasive pneumococcal disease (IPD).

DATA COLLECTION AND ANALYSIS

A) RCTs: trial quality assessment was conducted by two review authors and data extracted by three authors; odds ratios (OR) and 95% confidence intervals (CI) were estimated using a random-effects model.B) Non-RCTs: study quality, including measures to control for confounding, was assessed and data extracted by two review authors; OR and 95% CI were calculated using a random-effects model following the conversion of each study outcome to a log OR and standard error.

MAIN RESULTS

Twenty-two studies met our inclusion criteria (15 RCTs involving 48,656 participants and 7 non-RCTs involving 62,294 participants). Meta-analysis of the RCTs found strong evidence of PPV efficacy against IPD with no statistical heterogeneity (OR 0.26, 95% CI 0.15 to 0.46; random-effects model, I-squared (I(2)) = 0%). Efficacy against all cause pneumonia was inconclusive with substantial statistical heterogeneity (OR 0.71, 95% CI 0.52 to 0.97; random-effects model, I(2) = 87.3%). PPV was not associated with substantial reductions in all-cause mortality (OR 0.87, 95% CI 0.69 to 1.10; random-effects model, I(2) = 75.3%). Vaccine efficacy against primary outcomes appeared poorer in adults with chronic illness but the difference was not statistically significant. Non-RCTs provided evidence for protection against IPD in populations for whom the vaccine is currently utilised (OR 0.48, 95% CI 0.37 to 0.61; random-effects model, I(2) = 31.4%).

AUTHORS' CONCLUSIONS

This meta-analysis provides evidence supporting the recommendation for PPV to prevent IPD in adults. The evidence from RCTs is less clear with respect to adults with chronic illness. This might be because of lack of effect or lack of power in the studies. The meta-analysis does not provide compelling evidence to support the routine use of PPV to prevent all-cause pneumonia or mortality.

Cost-effectiveness of pneumococcal vaccination for prevention of invasive pneumococcal disease in the elderly: an update for 10 Western European countries

Pneumococcal vaccine is effective in preventing invasive pneumococcal disease in adults >or=65 years of age, but it is not widely used in Western Europe. In this study, data from an earlier (1995) cost-effectiveness study on Belgium, France, Scotland, Spain, and Sweden are updated, and data on five new countries--Denmark, the UK (specifically, England and Wales), Germany, Italy and The Netherlands--are added. Epidemiological and economic variables specific for each country were used, and it was assumed that pneumococcal and influenza vaccines would both be administered during the same physician visit. In the base-case analyses, the cost-effectiveness ratios ranged from euro 9239 to euro 23,657 per quality-adjusted life-year. Because the incidence and mortality of invasive pneumococcal disease were underestimated in most countries, a country-by-country analysis was performed, assuming an incidence of 50 cases per 100,000 population and mortality rates of 20, 30 and 40%. For a mortality of 20%, the cost-effectiveness ratios ranged from euro 4,778 to euro 17,093, and for a mortality of 30%, they ranged from euro 3,186 to euro 11,395. Pneumococcal vaccination to prevent invasive pneumococcal disease in elderly adults was very cost-effective in all 10 countries. This evidence justifies the wider use of the vaccine in Western Europe.

Advances in Pneumococcal Vaccines

Streptococcus pneumoniae causes considerable morbidity and mortality in the elderly. There are three established approaches to pneumococcal vaccination: polysaccharide vaccines, protein-polysaccharide conjugate vaccines and protein-based vaccines. This article reviews advances in anti-pneumococcal vaccines, with reference to advantages and shortcomings for the elderly in particular. The 23-valent polysaccharide pneumococcal vaccine (PPV) is currently recommended for high-risk patients and the general elderly population. Although the effectiveness of PPV against pneumonia is unclear, recent studies point to significant protective effects in preventing pneumococcal pneumonia and reducing the severity of disease in vaccinated elderly patients. PPV offers high serotype coverage and, although it is poorly immunogenic in some individuals, provides approximately 60% protection against invasive disease in the general elderly population. PPV vaccination appears cost effective for elderly patients although the vaccine might only be effective in preventing invasive disease. Additional benefits could mean a greater level of vaccine cost effectiveness. However, it is important to understand that PPV provides incomplete protection, especially in those with underlying high-risk conditions, and development of more effective pneumococcal vaccination strategies for elderly patients is still needed. In recent years, the most important advance in the prevention of pneumococcal infections in the elderly has been the introduction of a 7-valent conjugate pneumococcal vaccine (CPV) as a routine vaccination for infants. In addition to dramatically reducing invasive infection in children, CPV has been observed to have a considerable indirect protective effect in parents and grandparents. While the possibility of using CPV in elderly patients has been suggested, currently there are only limited immunogenicity data and no efficacy data in adults. The low serotype coverage is an important shortcoming and if CPV were to be used in the elderly, it would need to be given sequentially with the PPV. New CPVs covering more serotypes are currently under investigation, and these could be an alternative for use in all groups in the future. Numerous protein-based vaccine candidates offer the potential advantage of prevention against infections caused by all pneumococcal serotypes. Several are in various stages of development in animal models, but none can be expected to be available in clinical practice for several years at least. To date, the 23-valent PPV is still the best anti-pneumococcal vaccine option in the management of elderly persons. Introduction of the 7-valent CPV as a routine vaccine for children has provided considerable indirect benefits for older adults via herd immunity, but this vaccine has limited serotype coverage in elderly individuals. New CPVs including more serotypes (various CPVs are in different phases of pre-licensure studies) could prove to be good options in the future for all age groups. Several protein-based pneumococcal vaccine candidates (currently under investigation in animal models) offer the potential advantage of serotype independent protection, but none can be expected to be available in clinical practice in the near future.