The aim of this prospective case-control study is to investigate the prevalence, severity and incidence of systemic consequences in newly detected patients with mild and moderate Chronic obstructive pulmonary disease (COPD). Special attention will be paid to skeletal muscle dysfunction and physical inactivity as these factors are, together with smoking, potentially modifiable.

Three groups will be included in this study:

• Patients with COPD (cases)
• Patients with smoking history but no COPD (smoking controls)
• Patients with no smoking history and no COPD (non-smoking controls)

An extensive test battery will be performed at baseline and after 3 years:

Clinical assessment (height, weight and blood pressure)*

Complete pulmonary function ((post-bronchodilator)spirometry + diffusion)*

Sputum Induction

Fasting venous blood sample (fasting glucose, cholesterol, triglycerides, inflammatory markers, creatinine, NT pro BNP, hemoglobin, testosterone, vitamin D)

Vascular screening (arterial stiffness - arterial stenosis - CIMT)

Muscle force (peripheral + respiratory)*

Functional exercise capacity (6 MWT)**

Maximal exercise capacity (incremental cycle test)**

Dexa scan (osteoporosis - body composition)

Spiral CT scan of the chest

RX thorax - RX lumbar

Questionnaires (MRC, CCQ, SF-36, EQ5D, HADS, Exacerbation, CATZ)**

Physical activity monitoring (sensewear armband)*

* test will be repeated every 6 months

** test will be repeated every year

!!!! Remark (26/9/2013) Based on the last data analyses, in contrast to our expectations, we concluded that the two groups with a smoking history, with or without COPD change in a similar way over time. The length of the study will therefore be prolonged with 3 more years (6 years in total).

After 3 years the patients with a smoking history will be evaluated yearly, unless they were hospitalized for >5 days. In that case we will sooner contact these patients in order to pick up comorbidities in these patients.!!!

Inclusion Criteria:

• age 40-80 years old

cases: spirometry (post-bronchodilator) based diagnosis of COPD (GOLD criteria) + smoking history of at least 10 pack-years and active smoking behavior till at least 10 years from the moment of enrollment.

smoking controls: no COPD (spirometry based) + smoking history of at least 10 pack-years and active smoking behavior till at least 10 years from the moment of enrollment.

non-smoking controls: no COPD (spirometry based) + < 1 pack year

Exclusion Criteria:

• Respiratory disorder other than COPD
• α1-antitrypsin deficiency
• Known history of significant inflammatory disease other than COPD
• COPD exacerbation within 4 weeks prior to study
• Lung surgery
• Recent diagnosis of cancer
• Therapy with oral corticosteroids in the last 6 weeks
• Significant cardiovascular comorbidity
• Significant orthopedic/musculoskeletal problems

Population-based sample from the general population: random selected patients from the environment of Leuven (Nelson Study), and co-workers from the University Hospital of Leuven