Muscle Dysfunction in Patients With Chronic Obstructive Lung Disease (COPD): the Role of Sympathetic Activation

Exclusion Criteria

• •not willing or unable to sign the informed consent before the study begins
• •Age under 30 or over 80 years
• •paO2\< 55 mmHg or PaCO2 \> 45 mmHg on arterial blood gas analysis (For patients on NIV, PaCO2 values of up to 55 mmHg are acceptable.)
• •Treatment with drugs having direct sympathomimetic activity (e.g. theophylline, moxonidine, clonidine)
• •Oral medication with beta2 sympathomimetics (therapy with long-acting inhaled beta2 sympathomimetics is permitted)
• •History of sleep apnoea or documented evidence of \> 15 episodes of apneas and/or hypopnea per hour during sleep. An episode of apnea is defined as the cessation of inspiratory airflow for 10 s or more. Hypopnea is defined as a reduction in airflow (\> 50%) lasting for more than 10 s in comparison with the maximum airflow recorded during the preceding breathing cycle.
• •Myocardial infarction (MI) or a coronary revascularization procedure within the previous 2 calendar months
• •Clinically evident polyneuropathy
• •Diabetes mellitus necessitating any pharmacologic therapy
• •Severe (i.e., life-limiting) concomitant disease, including life-threatening malignancy (cancer likely to reduce life expectancy to less than 5 years), acquired immune deficiency syndrome, or any other life-threatening disease.
• •Diuretics should not be taken before measurements