Comparison of Clinical Status of Individuals With COPD and Preserved Ratio Impaired Spirometry

Exercise capacity is assessed using the 6-minute walk test (6MWT). The 6MWT is performed according to the criteria of the American Thoracic Society.

Arterial stiffness is evaluated with a Tel-O-Graph CT device with oscillometric cuff (I.E.M., Stolberg, Germany). Central systolic blood pressure, pulse wave velocity (PWV) and augmentation index (Alx) are measured with brachial pulse waves. After a five-minute rest, three measurements are performed in a quiet environment.

Muscle oxygenation is assessed using a measurement and monitoring device (Moxy Fortiori Design LLC, Minnesota, USA). The device is placed on the vastus lateralis muscle. Resting measurements are taken for at least 3 minutes until the muscle oxygen saturation (SmO2) signal stabilizes. SmO2 at rest, SmO2 during 6DYT and during the first minute of recovery, and mean SmO2 are recorded.

Physical activity levels is assessed using the International Physical Activity Questionnaire-Short Form (IPAQ-SF). The IPAQ requires respondents to estimate time spent in various levels of physical activity during the previous week. Scores for walking and moderate and vigorous activities are calculated as durations and frequencies multiplied by known metabolic equivalents per activity. The results for all activity-based items are summed for the total physical activity score. The participants were then categorized as inactive, minimally active and sufficiently active according to the IPAQ categorical classification.

Body composition is evaluated by Bioelectrical Impedance Analysis method. For body composition measurement, it is completed in an upright posture, without moving, leaving a space between the arms and torso, ensuring full contact of the hands and feet with the electrodes. Muscle mass, fat mass, body fat percentage (BMR) and lean body weight (LBW) values of the participants are recorded.

Respiratory Muscle Strength is measured using a mouth pressure meter (MicroRPM, Micro Medical, Rochester, UK) and personalized antibacterial and antiviral disposable filters; maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) values are determined.

Peripheral muscle strength is measured by knee extensor muscle strength measurement. Measurements are performed with a portable digital muscle strength measuring device (01165 Manual Muscle Tester, Lafayette Instrument Co. Lafayette, USA).

Sleep quality is measured by the Pittsburgh Sleep Quality Index (PSQI). The scale assesses sleep quality and sleep disturbance over the past month. The scale includes 24 questions. The total PDQI score ranges from 0-21 points. A total score greater than 5 points indicates "poor sleep quality".

The COPD Assessment Test, COPD Assessment Test Questionnaire (CAT), is an eight-item self-reported scale scored on a 0-5 point scale to assess symptoms associated with COPD. As a clinical impact, a total score of less than 10 points is interpreted as few symptoms, while a score of more than 10 points is interpreted as more symptoms.

Quality of Life will be assessed with the St George Respiratory Questionnaire (SGRQ). SGRQ is a 76-item health-related quality of life assessment questionnaire.

Symptoms, dyspnea and fatigue level are assessed. Dyspnea is assessed with the modified Medical Research Council (mMRC) dyspnea scale. Fatigue levels of individuals will be assessed using the Fatigue Severity Scale (FSS).

Testing procedures is in accordance with the guidelines published by ATS/ERS. A portable spirometer is used for assessment. Pulmonary function testing assesses forced vital capacity (FVC). FVC is the volume of air exhaled with rapid and forceful exhalation following deep inspiration.

Testing procedures is in accordance with the guidelines published by ATS/ERS. A portable spirometer is used for assessment. Pulmonary function testing assesses forced expiratory volume in the first second (FEV1). Forced vital capacity is the volume of air removed in the first second from the start of the maneuver.

Testing procedures is in accordance with the guidelines published by ATS/ERS. A portable spirometer is used for assessment. Pulmonary function testing assesses FEV1/FVC.

Testing procedures is in accordance with the guidelines published by ATS/ERS. A portable spirometer is used for assessment. Pulmonary function testing assesses peak flow rate (PEF). PEF is measured by maximal inspiration followed by maximal exhalation maneuver.

Testing procedures is in accordance with the guidelines published by ATS/ERS. A portable spirometer is used for assessment. Pulmonary function testing assesses forced expiratory flow from 25-75% (FEF25-75%). FEF25-75% mean flow rate at 50% of the forced vital capacity maneuver.