The prevalence of sarcopenia is high in many organ pathologies such as COPD, but remains little studied in acute respiratory failure. Sarcopenia is a health problem representative of frailty, loss of autonomy and decreased muscle strength. The frequency and evolution of sarcopenia is unknown in patients having chronic bronchic obstruction with exacerbation.

• Investigator consecutively included patients with known persistent airflow obstruction, hospitalized in Pneumology Department at the CHU Gabriel Montpied in Clermont-Ferrand.
• Investigator offered to participate to an observational study involving nutritional evaluation (recommended by national and international authorities) complementary to their usual respiratory care, and a 6 months' follow-up consultation: examination and surveys, mid-arm muscle circumference, body composition, spirometry.
• This enables to assess sarcopenia as a low mid-arm muscle area, by measuring the mid-arm muscle circumference of the dominant side and the triceps skinfold thickness.
• The primary endpoint is to determine the prevalence of sarcopenia, via the brachial muscular circumference, of chronic obstructive patients hospitalized in Pneumology department.
• The data entry (clinical, biological and radiological) is carried out on site, during the initial consultation and follow-up, directly on the computerized patient file. These data will then be retrieved and entered in an Excel spreadsheet, anonymously (anonymous identification number, gender and age).
• Management of censored data (lost to follow-up, cessation or withdrawal of study): each patient has a "computerized patient record" with phone numbers, checked during the first consultation and updated if necessary. The patient is called back one month before the follow-up consultation to confirm the appointment. If it is impossible to come, the patient will be offered another appointment, within one month of his initial appointment.
• Lost participants will not be excluded from statistical analyses.
• The expected number of subjects is 50.
• Oral and written consent is asked at the beginning of the consultation proposing participation in the study and follow-up at 6 months.

Inclusion Criteria:

• Age ≥ 18 years
• A history of persistent airflow obstruction (a post-bronchodilator FEV1/FVC < 0.7 of the predicted value after 400 ug of inhaled salbutamol) compatible with respiratory function tests (according to the GOLD definition)
• Informed consent to examination of nutritional status

Exclusion Criteria:

• Bronchopulmonary cancer being treated
• Disabling rheumatic disease
• Recent stroke or surgery (< 3 months)
• Missing data on essential variables (BMI, mid-arm muscle circumference)

chronic obstructive patients