Clinical impact of obesity on respiratory diseases: A real-life study.

BACKGROUND: Obesity has become an epidemic that affects Mexico; significantly interferes with respiratory physiology by decreasing lung volumes, therefore, might be considered as a relevant risk factor associated with the development of respiratory diseases. OBJECTIVE: Our primary outcome was to analyze the frequency and risk factors between obesity and respiratory disease in the Mexican population. MATERIALS AND METHODS: An observational, single-center, descriptive study, which included the totality of patients who were referred for medical attention at the Respiratory and Thorax Surgery Unit at the Hospital Regional de Alta Especialidad de la Península de Yucatán during the period from January 2015 to December 2018. The cases were grouped based on the existence or not of respiratory disease and the presence or absence of obesity (body mass index [BMI] >30 kg/m2). RESULTS: A total of 1167 patients were included; about 39% of the population had average BMI 36.5 kg/m2. The primary respiratory diseases in obese patients were Obstructive Sleep Apnea Syndrome (OSAS, 19%) and asthma (15%). The logistic regression analysis showed a direct association between the presence of obesity with respiratory disease (odds ratio 1.58, 95% confidence interval 1.22-2.03, P < 0.001), the strength of this association was related with asthma and OSAS. CONCLUSION: The presence of obesity is an independent risk factor for respiratory disease, primarily for OSAS and asthma.

Pulmonary function and functional capacity in COVID-19 survivors with persistent dyspnoea.

The purpose of this study was to examine the physiological mechanisms of persistent dyspnoea in COVID-19 survivors. Non-critical patients (n = 186) with varying degrees of COVID-19 severity reported persistent symptoms using a standardized questionnaire and underwent pulmonary function and 6-minute walk testing between 30 and 90 days following the onset of acute COVID-19 symptoms. Patients were divided into those with (n = 70) and without (n = 116) persistent dyspnoea. Patients with persistent dyspnoea had significantly lower FVC (p = 0.03), FEV1 (p = 0.04), DLCO (p = 0.01), 6-minute walk distance (% predicted, p = 0.03), and end-exercise oxygen saturation (p < 0.001), and higher Borg 0-10 ratings of dyspnoea and fatigue (both p < 0.001) compared to patients without persistent dyspnoea. We have shown that dyspnoea is a common persistent symptom across varying degrees of initial COVID-19 severity. Patients with persistent dyspnoea had greater restriction on spirometry, lower DLCO, reduced functional capacity, and increased exertional desaturation and symptoms. This suggests that there is a true physiological mechanism that may explain persistent dyspnoea after COVID-19.