SynthesisBMJ open2020
Does intermittent exposure to high altitude increase the risk of cardiovascular disease in workers? A systematic narrative review.
Synthesis in BMJ open, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
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Who cites it
12 citing papers in PubMed, 15 citations in OpenAlex.
- Excessive erythrocytosis and the hypertensive phenotype at high altitude: emerging evidence and unresolved questions.Frontiers in cardiovascular medicine · 2026Review
- Cardiovascular risk and obesity in miner workers exposed to intermittent hypobaric hypoxia in the Peruvian Andes.Frontiers in physiology · 2026Article
- Cardiovascular and autonomic modulation during nighttime rest under real-world conditions in miners exposed to chronic intermittent hypoxia.Frontiers in physiology · 2026Article
- Effects of long-term very high-altitude exposure on cardiopulmonary function of healthy adults in plain areas.Scientific reports · 2025Observational
- Effects of Resveratrol on Intestinal Flora and Metabolism in Rats With Non-Steroidal Anti-Inflammatory Drug-Induced Intestinal Injury Under Plateau Hypoxia Environment.Food science & nutrition · 2025Article
- Effect of intermittent normobaric hypoxia on executive functions assessed with different cognitive tests in healthy young subjects.Frontiers in psychology · 2025Article
- Data-driven identification of metabolic and cardiovascular biomarkers in high-altitude workers: a machine learning approach.Frontiers in public health · 2025Observational
- Article
- Selected Exogenous (Occupational and Environmental) Risk Factors for Cardiovascular Diseases in Military and Aviation.Journal of clinical medicine · 2023Review
- Does Hypoxia and Stress Erythropoiesis Compromise Cardiac Function in Healthy Adults? A Randomized Trial.Sports medicine - open · 2022Article
- Healthy worker survival effect at a high-altitude mine: prospective cohort observation.Scientific reports · 2022Article
- Cardiac Autonomic Modulation and Response to Sub-Maximal Exercise in Chilean Hypertensive Miners.Frontiers in physiology · 2022Article
Corrections and comments
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Authors and funding
5 authors at 2 institutions in 3 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveSeveral working groups (eg, miners, flight crews and soldiers) are subjected to chronic intermittent hypoxic exposure. The cardiovascular implications have been studied but not systematically reviewed with focus on possible negative health implications. The aim of the present review was to systematically evaluate the hypothesis that intermittent hypoxic exposure causes cardiovascular stress detrimental to health in workers.
designSystematic review. DATA SOURCES: Electronic database search of PubMed, Scopus and Web of Science up to April 2020. ELIGIBILITY CRITERIA: Studies of workers ≥18 years repeatedly subjected to months to years of irregular intermittent hypoxia, lasting from a few hours (eg, flight crews), one or a few days (eg, soldiers), or several days to weeks (eg, miners working at high altitude), written in English and evaluating the effect of intermittent hypoxia on cardiovascular disease were included. Animal studies, books, book chapters, personal communication and abstracts were excluded. The primary outcome measure was changes in standardised mortality ratio. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers extracted data and assessed risk of bias using the Cochrane Collaboration's tool.
results119 articles were identified initially, 31 of which met the inclusion criteria. Of these, 17 were retrospective cohort mortality studies (irregular short-term intermittent hypoxia), and 14 studies were observational (long-term intermittent hypoxia). The population of irregular short-term intermittent hypoxia users (flight crew) showed a lower mortality by cardiovascular disease. Long-term intermittent hypoxia over several years such as in miners or soldiers may produce increased levels of cardiac disorders (12 studies), though this is probably confounded by factors such as obesity and socioeconomic status.
conclusionThis systematic narrative review found that cardiovascular disease mortality in flight crews is lower than average, whereas miners and soldiers exposed to intermittent hypoxia experience increased risks of cardiovascular diseases. The impact of socioeconomic status and lifestyle appears of importance. PROSPERO REGISTRY NUMBER: CRD42020171301.
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