Altitude and COPD prevalence: analysis of the PREPOCOL-PLATINO-BOLD-EPI-SCAN study

Abstract

BackgroundCOPD prevalence is highly variable and geographical altitude has been linked to it, yet with conflicting results. We aimed to investigate this association, considering well known risk factors.MethodsA pooled analysis of individual data from the PREPOCOL-PLATINO-BOLD-EPI-SCAN studies was used to disentangle the population effect of geographical altitude on COPD prevalence. Post-bronchodilator FEV1/FVC below the lower limit of normal defined airflow limitation consistent with COPD. High altitude was defined as >1500 m above sea level. Undiagnosed COPD was considered when participants had airflow limitation but did not report a prior diagnosis of COPD.ResultsAmong 30,874 participants aged 56.1 ± 11.3 years from 44 sites worldwide, 55.8% were women, 49.6% never-smokers, and 12.9% (3978 subjects) were residing above 1500 m. COPD prevalence was significantly lower in participants living at high altitude with a prevalence of 8.5% compared to 9.9%, respectively (p < 0.005). However, known risk factors were significantly less frequent at high altitude. Hence, in the adjusted multivariate analysis, altitude itself had no significant influence on COPD prevalence. Living at high altitude, however, was associated with a significantly increased risk of undiagnosed COPD. Furthermore, subjects with airflow limitation living at high altitude reported significantly less respiratory symptoms compared to subjects residing at lower altitude.ConclusionLiving at high altitude is not associated with a difference in COPD prevalence after accounting for individual risk factors. However, high altitude itself was associated with an increased risk of undiagnosed COPD.

Muscle metabolomics analysis reveals potential biomarkers of exercise‑dependent improvement of the diaphragm function in chronic obstructive pulmonary disease

“…In the present study, CSE was used in the process of establishing animal models of COPD, which has been applied in numerous studies. However, the factors leading to COPD formation are complex: Multiple etiologies are considered to be associated with the occurrence of COPD, such as cigarette smoke, air pollution, metabolic derangements, genetics and aging (1,115). Unfortunately, the present study only simulated a COPD animal model using cigarette smoke, which is one of the study limitations.…”

“…chronic obstructive pulmonary disease (cOPd) is becoming a significant cause of mortality and disability worldwide due to the aging population, the increasing number of smokers and worsening air pollution (1). Among the numerous symptoms of cOPd, the decline of the respiratory function is a crucial factor affecting the quality of life of patients (2), and the respiratory failure caused by respiratory muscle dysfunction is the most severe symptom of cOPd, given that respiratory failure is closely related to the mortality rate of patients with COPD.…”

Chemerin: A Potential Regulator of Inflammation and Metabolism for Chronic Obstructive Pulmonary Disease and Pulmonary Rehabilitation

“…In addition, a variety of extrapulmonary pathological manifestations on distal organs, the so-called systemic effects and comorbidities of COPD, have been confirmed in patients with COPD [2]. In recent years, both global incidence and mortality of COPD have increased dramatically due to aging in many populations, increased smoking, and deterioration of air quality [3]. COPD is set to become the third leading cause of death and the fifth leading cause of disability in the world before 2030 [4].…”

Comparison of complete blood counts of stable COPD patients at two different altitude in Turkey.

“…4 In COPD patients living in high altitude areas, altitude could induce a higher growth of airways relative to lung size, causing to an increased FEV1/FVC ratio and it may cause chronic hypoxia. 5 In high altitude, to compensate for the low pressure of oxygen, many physiological changes occur in the human blood circulation. In response to hypoxia, the humanbody adapts to the tissues by increasing the distribution of oxygen.…”