Pulmonary Disease, Chronic ObstructiveLung Diseases, ObstructiveAsthmaForced Expiratory VolumeBronchodilator AgentsSpirometryRespiratory Function TestsVital CapacityDyspneaPulmonary EmphysemaAdministration, InhalationLungScopolamine DerivativesSmokingOxygen Inhalation TherapySeverity of Illness IndexSputumExercise ToleranceCholinergic AntagonistsEmphysemaAlbuterolIpratropiumAdrenal Cortex HormonesSleep Apnea, ObstructiveRespiratory MusclesBronchiSmokeAdrenergic beta-2 Receptor AgonistsQuality of LifeBronchitis, ChronicRespiratory InsufficiencyPulmonary MedicineRespiratory System AgentsTreatment OutcomeInspiratory CapacityLung DiseasesNebulizers and VaporizersCase-Control StudiesBronchitisRisk FactorsRespiratory TherapyExpectorantsRespiratory Mucosaalpha 1-Antitrypsin DeficiencyProspective StudiesPneumoniaHospitalizationInhalationQuestionnairesPositive-Pressure RespirationBreathing ExercisesHypercapniaExercise TestBronchoalveolar Lavage FluidOxygenTime FactorsBlood Gas AnalysisAirway ObstructionWork of BreathingRespiratory MechanicsMetered Dose InhalersRespiration, ArtificialPrevalenceDouble-Blind MethodDisease ProgressionCross-Sectional StudiesExhalationNoninvasive VentilationAirway ResistanceChronic DiseaseComorbidityHome Care Services, Hospital-BasedEthanolaminesRetrospective StudiesHeliumPhosphodiesterase 4 InhibitorsLung Volume MeasurementsRespiratory SystemAnti-Asthmatic AgentsBudesonideBronchoscopyAcute DiseasePulmonary Gas ExchangeGlucocorticoidsAdrenergic beta-AgonistsExercise TherapyAirway RemodelingPeak Expiratory Flow RateCoughCohort StudiesPulmonary VentilationAnti-Inflammatory AgentsInflammationBiological MarkersBreath TestsTotal Lung CapacityDiaphragmRespiratory Tract DiseasesGlycopyrrolateStatistics, Nonparametric