RESUMEN
INTRODUCTION: The MEGA (MEchanism underlying the Genesis and evolution of Asthma) project is a multicenter cohort study carried out in eight Spanish hospitals, gathering clinical, physiological, and molecular data from patients with asthma and multimorbidities in order to gain insight into the different physiopathological mechanisms involved in this disorder. MATERIAL AND METHODS: We report the baseline clinical and physiological characteristics and biomarker measures of adult participants in the project with the aim of better understanding the natural history and underlying mechanisms of asthma as well as the associated multimorbidities across different levels of severity. We carried out a detailed clinical examination, pulmonary function testing, measurement of fractional exhaled nitric oxide (FeNO), blood counts, induced sputum, skin prick tests, chest computed tomography scan, asthma questionnaires, and multimorbidity assessment in 512 asthmatic patients. RESULTS: When compared to patients with milder disease, severe asthmatic patients showed greater presence of symptoms, more exacerbations, lower asthma control, increased airflow obstruction, and higher frequency of chronic rhinosinusitis with nasal polyps, severe rhinitis, anxiety and depression, gastroesophageal reflux, and bronchiectasis. CONCLUSION: The MEGA project succeeded in recruiting a high number of asthma patients, especially those with severe disease, who showed lower control and higher frequency of multimorbidities.
RESUMEN
El objetivo general del estudio es la creación de una cohorte de pacientes con asma con distintos grados de gravedad, que permita incrementar los conocimientos sobre los mecanismos subyacentes a la génesis y evolución de esta patología. Los objetivos específicos se centran en llevar a cabo diferentes estudios en términos de imagen, de función pulmonar, inflamación e hiperrespuesta bronquial, para determinar los eventos relevantes que dan forma a esta población asmática, los parámetros a largo plazo que pueden determinar los cambios en la gravedad de los pacientes y que tratamientos pueden influir en la progresión de la enfermedad. El estudio también tratará de identificar las causas de las exacerbaciones y cómo esto afecta a la evolución de la enfermedad. Los pacientes serán contactados a través de las consultas externas de las 8instituciones participantes en el marco del CIBER de Enfermedades Respiratorias. En la visita de inclusión, se realizará una historia clínica estandarizada, un examen clínico exhaustivo, incluyendo la presión arterial, el índice de masa corporal, las pruebas funcionales respiratorias completas y la medición de la FENO, y se administrarán los cuestionarios Test de control del asma (ACT), Morisky Green, Cuestionario de calidad de vida en pacientes con asma (Mini AQLQ), el Cuestionario sino-nasal Outcome Test 22 (SNOT-22) y la escala de ansiedad y depresión (HAD). Para la recogida de los datos se ha diseñado una base de datos electrónica específica. Se recogerán también muestras de aire exhalado condensado, orina y sangre. Al inicio del estudio y cada 24 meses, se realizará una prueba de hiperrespuesta bronquial inespecífica con metacolina y se recogerá una muestra de esputo inducido. Al inicio del estudio se realizarán prick test a neumoalérgenos y una tomografía computarizada torácica que se repetirá a los 5 años
The general aim of this study is to create a cohort of asthma patients with varying grades of severity in order to gain greater insight into the mechanisms underlying the genesis and course of this disease. The specific objectives focus on various studies, including imaging, lung function, inflammation, and bronchial hyperresponsiveness, to determine the relevant events that characterize the asthma population, the long-term parameters that can determine changes in the severity of patients, and the treatments that influence disease progression. The study will also seek to identify the causes of exacerbations and how this affects the course of the disease. Patients will be contacted via the outpatient clinics of the 8 participating institutions under the auspices of the Spanish Respiratory Diseases Networking System (CIBER). In the inclusion visit, a standardized clinical history will be obtained, a clinical examination, including blood pressure, body mass index, complete respiratory function tests, and FENO will be performed, and the Asthma Control Test (ACT), Morisky-Green test, Asthma Quality of Life Questionnaire (Mini AQLQ), the Sino-Nasal Outcome Test 22 (SNOT-22), and the Hospital Anxiety and Depression scale (HADS) will be administered. A specific electronic database has been designed for data collection. Exhaled breath condensate, urine and blood samples will also be collected. Non-specific bronchial hyperresponsiveness testing with methacholine will be performed and an induced sputum sample will be collected at the beginning of the study and every 24 months. A skin prick test for airborne allergens and a chest CT will be performed at the beginning of the study and repeated every 5 years