The CAPNETZ Study – the centerpiece of the CAPNETZ STIFTUNG

Centerpiece of the CAPNETZ STIFTUNG is the CAPNETZ study devoted to community-acquired pneumonia (CAP) in adults. With its ever-growing unique database and biomaterial collection, the CAPNETZ study investigates scientific issues relating to  CAP. While open questions remain, the engagement of our associated scientists, clinicians and physicians is still  unbroken.

The current focus of the study are reciprocal interactions between CAP and comorbidities, improved pathogen diagnostics, identification of patient risk groups, and the role of immunosuppression in CAP.

The CAPNETZ study is an observational study on community-acquired pneumonia (CAP) in adults and the main project of the CAPNETZ STIFTUNG. After two decades of study implementation, CAPNETZ STIFTUNG looks back on a comprehensive database of over 14 000 data sets of CAP patients. This unique data collection is the basis on which many projects in fundamental and clinical research on CAP and other respiratory infections is built. Continue for more details.

2002: Start of the research initiative

The foundation of the ambitious project was laid in 2002: Through funding of the German ministry for education and research a “network of competence” was initiated around several clinical centres in Germany.  The network encompassed a study infrastructure for a prospective, longitudinal, and multi-centre observational study, and a detailed data and biomaterial collection. Since then, every year, high numbers of patients of community-acquired pneumonia are recruited and observed over a time span of 180 days. Associated clinical data, microbiological and laboratory results, and patient samples are collected and stored centrally.

Since the start of the CAPNETZ study, a multitude of scientific questions were answered owing to the data collection on pathogens and their epidemiology, treatments and antibiotic resistance, and on optimal therapy management for the patients.

A prognostic factor: pathogen identification

A rapid identification of the etiological agent facilitates focused antibiotic treatment. Therefore, the CAPNETZ effort for bacterial and virological diagnostics was strengthened by amendment of the study protocol in 2017. Previously, a reduction in cases with identified pathogen was observed. To overcome structural and economic limitations in diagnostic procedures at the clinics, two centralized diagnostics units were added to the study infrastructure, to improve patient outcome and epidemiological surveillance.

Collecting epidemiology data

A primary objective of the CAPNETZ study is the acquisition of data on prevalence and incidence of CAP in relation to patient risk factors such as underlying chronic illnesses. By recording comorbidities of CAP patients, interactions between pathological mechanisms can be uncovered. It has become clear that CAP constitutes an inflammatory event that affects the course of pre-existing health conditions and can contribute to complications and adverse events of these conditions. Such disease interactions need to be considered in the health management of the individual patient.

CAP and immunosuppression

Over the course of time CAP-research has adapted to novel scientific inquiries. Alongside, also the CAPNETZ study evolves: Since 2017 patients with an immunosuppression background can be recruited. Immunosuppression as consequence of infection, chronic illness, medication or organ transplantation, results in poor CAP prognosis. Here, the spectrum of potential underlying pathogens differs from the population of non-immunocompromised patients, which we know much more about. Accordingly, clinical guidelines on CAP management might not be appropriate for immunocompromised patients. Therefore, CAP management strategies need to be established for persons with clinically relevant immunosuppression. This includes also patients with HIV – a study population that can be recruited to the CAPNETZ study since the protocol amendment in 2017. The data of these patients  aid answering questions on HIV-specific patient risk factors in respect to CAP such as age, immune state, and HI-viral load.

Identification of at-risk patients

Generally, the identification of patient groups that are at a high risk for complications and mortality is crucial for CAP management. Therefore, one arm of research out of the CAPNETZ cohort focusses on creation of an emergency protocol for CAP in the stationary sector, and primarily, on the description of patient risk factors.

Further objectives of the CAPNETZ study are

  • Improved disease prevention by evaluation of vaccination readiness against influenza, Covid-19, and Pneumococcal disease 
  • Improved diagnostics by conflation analysis of clinical and microbiological data
  • Establishment of a database on antibiotic resistance
  • Investigations of pathogen-host interactions
  • Expansion of the central biomaterial- and pathogen database

From the study to the practice

The coordination of numerous study centres, diagnostics and the biobank is very complex and requires a centralized data collection system in frame of which CAPNETZ study centres and coordination headquarters can access our certified study portal.

Patient recruitment begins with informing patients and getting consent for recording of clinical data and storage of samples. Then, at baseline visit, clinical data on disease symptoms, the medical history of the patient including comorbidities and other risk factors, risk scores, lab results, microbiological results, and medications are documented. Different biological samples are collected and sent to the biobank in Hannover: EDTA-blood, serum, plasma, urine, PAXGene-RNA and lower respiratory tract samples (e.g. sputum). Respiratory material is also send to the central bacteriology and virology labs in Lübeck and Freiburg. Hospitalised patients undergo further examinations and sampling on days 3 and 7. Two further long-term follow-ups are conducted also for ambulatory patients and constitute of a telephone visit for checking patient status after 28 and 180 days.

Patient safety and promotion of scientific research are our highest priority

The CAPNETZ study is conducted according to predetermined ethical standards. Coherent data monitoring ensures not only completeness and plausibility of our data, but also makes sure that the patient’s consent is always respected. Distribution of our data to researchers requires an intense data clearing process. Thus, in order to access our database, research institutions can officially apply for a CAPNETZ-associated research project.

Our data informs the national S3 guideline

Research on CAPNETZ data is frequently published at high-ranking scientific journals, and constitutes a fundamental source of the national S3 guideline on epidemiology, diagnosis, therapy, and management of CAP. The guideline is the result of a collaboration between the Paul-Erlich Gesellschaft, the German Respiratory Society, the German Infection Society, and the management board of the CAPNETZ STIFTUNG.