Characterizing Functional and Metabolic Manifestations in Chronic Obstructive Pulmonary Disease
Abstract
COPD is an important public health challenge which requires costly and rigorous treatment. Sixty-five million people worldwide have COPD and is the fourth leading cause of death. While characterized by persistent respiratory symptoms and airflow limitation due to airway abnormalities caused by exposure to noxious particles, the systemic manifestations of COPD expand far beyond the lung including muscle and brain function, alterations in body composition, and disturbances of gut and whole body metabolism. Thus the general aim of this dissertation is to advance the characterization of these functional and metabolic manifestations in COPD and is divided into 3 parts: Part 1) To phenotype patients with functional manifestations in large groups of COPD patients based on underlying factors such as lung function, body composition, and comorbidities. Part 2) To unravel metabolic disturbances underlying functional manifestations in relation to shifts in body composition (e.g., abdominal obesity) and daily exercise in COPD patients. Part 3) To explore a novel metabolic biomarker of reduced functional performance and overall health in COPD patients. Studies from Part 1 revealed COPD patients with muscle dysfunction show characteristics of a cognitive-metabolic impairment phenotype, influenced by the presence of hypoxia, whereas those with normal muscle function present a phenotype of metabolic syndrome and mood disturbances and cognitive function, oxygen saturation, exacerbation history, and gait speed explain 83% of the variation in functional balance in COPD patients. Studies from Part 2 revealed abdominal obesity COPD was associated with preserved muscle function and metabolic syndrome related comorbidities despite generally elevated BCAA clearance rates and that 20 minutes of walking exercise is sufficient to cause perturbations in gut function and whole body protein metabolism during and up to four hours post-exercise in COPD patients with exercise induced hypoxia. The study from Part 3 revealed postabsorptive whole body protein balance is reduced in COPD patients and is associated with markers of poor daily functioning. I believe these studies substantially add to the status quo of the field and can translate complex physiological principles to clinics for better design of treatment strategies for the global burden that is COPD.
Subject
COPDCitation
Cruthirds, Clayton Lyles (2021). Characterizing Functional and Metabolic Manifestations in Chronic Obstructive Pulmonary Disease. Doctoral dissertation, Texas A&M University. Available electronically from https : / /hdl .handle .net /1969 .1 /195636.