1. Background Chronic Obstructive Pulmonary Disease (COPD) is an inflammatory disease of the lungs, which is most commonly caused by smoking. It is characterized as not fully reversible airflow limitation, chronic cough and dyspnoea. Being the fourth leading cause of death worldwide, COPD is an important public health challenge and can be prevented and treated. It is estimated that at least 400,000 individuals in Switzerland are affected by COPD. This number may increase in the coming years due to increasing nicotine consumption.

   In response to the rising trend, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) has established new guidelines on the global strategy for diagnosis, management and prevention of COPD. Systematic diagnosis and stratification are crucial for effective treatment measures.

   As COPD is an irreversible and progressive disease, its treatment aims an early detection and better management, which leads preventing progression. Disease management programs have shown that only patients who understand their exacerbation symptoms can benefit. Moreover, it is a major goal to improve health-related quality of life by reducing symptoms and decelerating disease progression.

   Spirometry is the golden standard for the diagnosis of COPD, to assess the severity of the obstruction, and as a guide for optimal therapeutic measures.

2. Aim of the study The objective of this project is to establish a COPD cohort database to allow high quality research on diagnosis, treatment, complication and progression of COPD on long-term course.

   Spirometry should be used consistently for the diagnosis and the monitoring of the development of the disease. Using collected information such as spirometric data, disease progression's data and therapeutic measures should help improve the management and self-management of the patients.

3. Methods 3.1 Study design We are conducting a prospective cohort study, based on COPD patients from northern and western Switzerland, who are managed under primary care setting. Patients with mild to very severe COPD (GLOD stages I-IV) are enrolled in the study.

   Currently, 67 General practitioners (GPs) are participating in our Study. Each GP recruits 1-20 patients with presumed mild to very severe COPD according to criteria of the Global Initiative for Chronic Obstructive Lung disease [GOLD].

   Patients' follow-up-visits occurs at 6-month intervals; their history, symptoms and examination status is recorded. Data is entered into an online database either by the physicians or by study team after receiving the collected data questionnaires by facsimile.

   Data collection includes demographic data, physical examination, spirometric parameters, medical treatment and exacerbation history besides death.

   A spirometer (EasyOne™, ndd Medizintechnik AG, Zürich, Switzerland) is used to assess lung function. All participating physicians were instructed on the usage of the spirometer and on how to complete spirometry according to the guidelines. For the assessment of the severity of COPD, we use the spirometric data provided by the GPs. The COPD severity is interpreted according to criteria of the GOLD committee.

   3.2 Patient population Patients with newly diagnosed or existing COPD, who are managed in primary-care practices.

   3.3 Inclusion criteria

   • Tiffenau (FEV17FVC) < 70 without reversibility (Increase in FEV1 after inhalation of a bronchodilator <200 ml and <12%).
   • Age: > 40 years
   • Both genders
   • Smokers or ex-smokers of at least 20 pack years.
   • Informed consent.

   3.4 Archiving and Data Retention All study-related records such as medical records, informed consent documents, information regarding participants who discontinued, and other pertinent data will be maintained and therefore retained as long as required by the applicable Swiss regulatory requirements (10 Years).

   3.5 Data security The complete data of the study will be entered anonymously into a database. The data is password-protected and can only be accessed by investigators and study members.

4. Publication and authorship 4.1 Publication policy

Authorship credit is based on:

1. Substantial contribution to conception and design, acquisition of data, or analysis and interpretation of data.
2. Drafting the article or revising it critically for important intellectual content.
3. Final approval of the version to be published. Each author should have participated sufficiently in the work to take public responsibility for appropriate portions of the content.

Inclusion Criteria:

• Tiffenau (FEV17FVC) < 70 without reversibility (Increase in FEV1 after inhalation of a bronchodilator <200 ml and <12%).
• Age: > 40 years
• Both genders
• Smokers or ex-smokers of at least 20 pack years.
• Informed consent.

Exclusion Criteria:

• < 40 Years
• Tiffenau (FEV17FVC) > 70

Patients with newly diagnosed or existing COPD, who are managed in primary-care practices.