Aerospace medicine and human performance最新文献

Introduction: Long-duration space missions introduce stressors that can disturb the affective states of astronauts (e.g., isolation, workload). However, studies in space or in space-analog environments struggle to find a consensus on the affective impact of these stressors. Also, there is a lack of research using multiple measures to assess affective states in these conditions (e.g., positive and negative measures and physiological parameters). More research is needed to understand the psycho-physiological mechanisms during long-duration space-like missions. Our study was conducted during a space-analog confinement (SIRIUS-19). Throughout the mission, we assessed variations of affective states using subjective and physiological parameters. We expected interindividual variability, with transitory and chronic changes on the psychological and physiological dimensions of affective states.

Methods: Six subjects (three men/three women; four Russians/two Americans; age = 33.83 ± 6.37) performed the protocol once a month during the 4-mo confinement. Subjects completed various psychometric scales about their affective states (Self-Assessment Manikin, Positive and Negative Affective Schedule) and provided hair cortisol samples. Due to the small sample size, only individual values and descriptive statistics were used.

Results: Psychometric measures remained positive and stable. Hair cortisol levels increased at the beginning of the mission (from 31.79 ± 18.05 pg · mg-1 to 62.25 ± 31.99 pg · mg-1). Most of the measurements showed interindividual variability.

Discussion: The subjective affective states remained positive and relatively stable throughout the mission. The initial increase of hair cortisol is attributed to an adaptation phase of the crew. No affective variation seems to be related to this phase. Our results indicate effective affective adaptation to the confinement. Pauly J, Langlet C, Hainaut J-P, Yusupova A, Bolmont B. Affective states in a space-analog mission and insights from psychometric and hair cortisol measures. Aerosp Med Hum Perform. 2025; 96(5):436-442.

Background: Patients with lung disease can experience hypoxemia on commercial aircraft, which can usually be corrected with supplementary oxygen. In some cases, combinations of medical conditions and inability to deliver oxygen via simple methods can complicate assessment and delivery of flight oxygen.

Case report: A 53-yr-old woman with multiple comorbidities planned a 4-h commercial flight. She has end-stage obstructive lung disease, hypercapnic respiratory failure requiring home oxygen, and previous laryngeal cancer treated by total laryngectomy, resulting in a neck stoma. She is prescribed 28% oxygen therapy via a stoma Venturi mask requiring 4 L · min-1. An airline-approved oxygen concentrator was necessary for flight, providing a maximum 3 L · min-1, so we could not assess flight oxygen without changing the delivery method, although a direct stoma oxygen connection or the use of heat and moisture exchangers (HME) had been contraindicated for normal use. Hypoxic challenge testing with various delivery methods showed that 3 L · min-1 was sufficient to maintain oxygenation safely with little risk of hypercapnia. Fitting a stoma HME with integral oxygen attachment caused accumulation of secretions and minor desaturation, although the patient could clear them spontaneously. Ultimately HME use was approved for flight only, although other methods were successfully evaluated.

Discussion: Patients with respiratory conditions are often dissuaded from flying by healthcare professionals, especially in complex cases where guidelines do not address all combinations of medical conditions. With tailored assessment and advice, surgically altered airway anatomy should not preclude commercial air travel, even if supplementary oxygen is required. Spurling KJ, Loft J, Ottun S, Moonsie I. Preparing an oxygen-dependent passenger with a surgically altered airway for commercial air travel. Aerosp Med Hum Perform. 2025; 96(5):443-446.

Introduction: Fighter pilots endure significant physical stress due to elevated gravitational forces, leading to a high prevalence of neck pain. The biomechanical loads and operational demands of high-gravitational maneuvers highlight the need for targeted interventions. Exercise training has been proposed to mitigate neck pain and enhance musculoskeletal resilience. This review examines the effectiveness of exercise interventions and identifies research gaps requiring further exploration.

Methods: A PRISMA-guided systematic review examined randomized controlled trials and longitudinal studies on fighter pilot neck pain exercise interventions. Databases searched included PubMed, Cochrane Library, Defense Technical Information Center, and Web of Science, with search terms such as "fighter pilot," "aircrew," "exercise," "neck pain," "cervical," "Gz," and "conditioning." Two independent reviewers selected studies based on population, intervention, outcomes, and design. There were 5 studies that met the inclusion criteria, involving 199 participants.

Results: The findings were mixed regarding the effectiveness of exercise interventions in reducing neck pain. Three studies reported significant pain reduction, while two found no significant changes. Programs incorporating deep cervical muscle training and supervised sessions demonstrated more consistent positive outcomes. Improvements in neck muscle strength and endurance were observed across all studies. Training compliance was higher in supervised (58-77%) than unsupervised (28-41%) programs.

Discussion: Exercise interventions, particularly strength and endurance training, show the potential to improve neck muscle function in fighter pilots. However, mixed results on pain reduction, small sample sizes, and varied methodologies limit generalizability. Future research should employ standardized definitions of flight-related neck pain and robust methods to develop tailored exercise protocols. Acevedo A, Zeigler Z. Exercise training and neck pain in fighter pilots. Aerosp Med Hum Perform. 2025; 96(5):425-430.

Introduction: The military aviation environment is inherently noisy, with occupational noise hazards from a variety of sources. At the same time, it demands good binaural auditory acuity and speech discrimination abilities for the safe and effective performance of flight duties. This study aimed to 1) examine the burden, characteristics, and severity of abnormal audiograms among military aircrew and ground-based aviation personnel in the Republic of Singapore Air Force; and 2) elicit the risk factors associated with abnormal audiograms.

Methods: In this cross-sectional study, anonymized data (sociodemographic information, pure tone audiometry thresholds, anthropometric and physiological measurements, and biochemical investigations) were extracted from all consecutive unique annual certification examinations performed between January 1 and December 31, 2022. Multivariable logistic regression was performed to identify statistically significant risk factors associated with abnormal audiograms.

Results: Of the 1817 audiograms, 83 (4.6%) were abnormal based on the modified World Health Organization criteria. Abnormal audiograms featured an early bilateral high-frequency hearing loss pattern characteristic of noise-induced effects. The multivariable model retained only age and four vocations [i.e., Communication Equipment Specialist, Air Force Engineer (Flight Engineer), Air Warfare Officer (Air Battle Manager), and Unmanned Aerial Vehicle Pilot] as significant risk factors. Neither aircraft platforms nor specific engine types were associated with higher odds of developing abnormal audiograms.

Discussion: This study suggests that the modified World Health Organization criteria are useful in identifying at-risk subgroups within the military aircrew population and could be considered for use as a more sensitive screening threshold for early noise-induced hearing loss. Seah BZQ, Ng WT, Gan WH, Low JW, See B. Abnormal audiogram risk factors in military aircrew and ground-based aviation personnel. Aerosp Med Hum Perform. 2025; 96(5):378-385.

Introduction: This study examines the health status of pilots above age 60 and its impact on the workforce, focusing on those not returning to work.

Methods: Pilots from a major Japanese airline reaching age 60 between 2008-2013 were studied for the subsequent 5 yr ("senior pilots"). Disqualifying diseases, application for Aviation Medical Review Board (AMRB), disposition, and grounding periods during the 5 yr were compared with those of a pilot cohort reaching age 55 during the same period ("non-senior pilots").

Results: There were 263 senior and 202 non-senior pilots. For AMRB cases, cardiovascular diseases were significantly more common in senior pilots compared with non-senior pilots (10.3 vs. 4.0%, respectively). Senior pilots were less likely to apply for AMRB (9.9 vs. 3.5%) or return to work, i.e., the sum of those who were denied by and who did not apply for AMRB (12.2 vs. 5.0%) and also had a higher incidence of cardiovascular diseases (4.6 vs. 1.0%). The grounding period of those not returning to work within the 5-yr study period was significantly longer than the temporary grounding period in both groups of pilots (senior: 22.3 ± 15.7 vs. 6.3 ± 4.7 mo; non-senior: 24.2 ± 17.2 vs. 7.5 ± 8.6 mo, as mean ± SD, respectively).

Discussion: Medical disqualification in senior pilots is more frequent than with younger pilots and may have a greater impact on crew availability. Looking at ways of increasing the number of older pilots returning to work would benefit crew availability as would a focus on the prevention of cardiovascular diseases. Takazoe K, Gomi H. The health status of pilots over age 60 at a Japanese airline. Aerosp Med Hum Perform. 2025; 96(5):392-398.

Introduction: Expeditions in remote locations are becoming increasingly commonplace. As the composition of teams change, understanding team dynamics is important to inform subsequent expeditions in challenging environments.

Methods: Eight individuals (five men, three women; five military, three civilians) completed a ski expedition from the Ronne Ice Shelf to the South Pole over 47 d. A mixed methods observational cohort study was undertaken, involving completing pre-expedition Multidimensional Personality Questionnaires and Portrait Values Questionnaires. During the expedition individuals completed the Isolated and Confined Environments Questionnaire and the Positive and Negative Affect Scale at 7-d intervals. Subsequent semistructured interviews using a topic guide informed by Goffman's "total institution" were conducted and analyzed using reflexive thematic analysis.

Results: Multidimensional Personality Questionnaire and Portrait Values Questionnaire responses were similar between participants. The Isolated and Confined Environments Questionnaire results showed significant variation with no clear trend. Statistical significance was seen in social and emotional domains between sex and occupations. Positive and Negative Affect Scale scoring demonstrated higher positive affect (mean ± SD; 38.9 ± 1.5) to negative (13.1 ± 1.3). Subgroup analysis demonstrated significance for negative affect between sexes (one result skewed the data). The interviews highlighted that individuals found the routine and lack of personal space challenging. Interpersonal relationships were a source of support but also friction.

Discussion: Despite similar initial questionnaires and experiences during the expedition, subjects used a diverse range of coping strategies. Interpersonal factors remain the most important aspect in ensuring a successful team and pre-expeditionary work should be carried out focusing on this. Harper P, Albertsen N, Koivula F, Greenfield S, Thomas N. Psychological adaptation in a mixed sex and ability team during a ski expedition to the South Pole. Aerosp Med Hum Perform. 2025; 96(5):399-406.

Introduction: Real-time monitoring of pilots through physiological responses may provide a means of identifying onset of degraded states. This could potentially be used to introduce methods of preventing negative impacts to performance. However, few studies to date have examined whether quantitative physiological data can successfully be recorded in actual flight, with even fewer during extreme maneuvering.

Methods: An observational study was completed where physiological data was collected from three Army aviators while they completed an upset prevention and recovery training. The training was through a private company not affiliated with the Department of Defense. Subjects completed multiple flights within a small, acrobatic fixed-wing aircraft. Physiological data [electroencephalography (EEG) and electrocardiography] were recorded continuously in flight.

Results: The physiological data were evaluated for signal loss and signal quality. The electrocardiography signals were determined as excellent quality based on the metrics proposed previously, with minimal signal loss. Similarly, the EEG recordings had near zero loss of data, except for one of the participant's flights. The EEG quality was determined to be acceptable.

Discussion: This study demonstrates an important step in real-time monitoring. It was demonstrated that qualitative physiological data can successfully be recorded in flight during extreme maneuvering. Further research is needed to determine the utility of such data in relation to pilot state and performance. Demonstration that this type of data can be successfully collected in flight while pilots undergo extreme maneuvers provides promise for using these types of measures across a variety of flight scenarios where a pilot's cognitive states may become degraded. Yue X, Andres K, Duffy MJ, Rodriguez R, Aura CJ, Feltman KA. Measuring pilot physiology during in-flight training and implications for real-time monitoring. Aerosp Med Hum Perform. 2025; 96(5):447-452.

Introduction: Operators of rotary wing aircraft and high-performance jet aircraft often face musculoskeletal pain and cervical spine injury risks due to flight-related factors, including heavy vibrational and g-loading, abrupt head maneuvering, and a large number of flight hours. This study explores the use of a portable lightweight resistance band exercise device (PLED) to strengthen and stretch neck musculature, potentially mitigating these risks.

Methods: A multi-aircraft study building on an initial pilot study of 10 high-performance jet aircraft aviators involved both active-duty aviators and civilians. Over 6 wk, subjects engaged in targeted PLED-based exercises. Baseline and endpoint measurements were obtained. Quantitative measurements assessed range of motion (ROM) and endurance, while Visual Analog Scale reports tracked pain. A total of 47 subjects consented, with 26 completing the protocol. There were 21 subjects who were either lost to follow-up or withdrew due to scheduling conflicts.

Results: Analysis of this interventional study showed significant ROM improvement, increased muscular endurance, and reductions in pain magnitude. Subjects reported improvements in flexibility, strength, stiffness, and pain relief. Active-duty aviators noted improved ROM, quicker postflight recovery, and reduced in-flight pain.

Discussion: This collaborative Department of Defense-academia-Department of Veterans Affairs research highlights the effectiveness of regular PLED-based cervical musculature exercises in enhancing ROM and endurance. While promising, further research with larger datasets is needed to support definitive recommendations. Moreover, the study's findings may benefit a broad population engaging in activities that stress the cervical spine and surrounding musculature. Keller RJ, Rosenthal R, Dalal S, O'Conor D, Ramachandran V, Vandeven S, Butler N, Shivers B, Shender B, Jones JA. Exercise regimen for mitigation of neck pain in military aircrew and support personnel. Aerosp Med Hum Perform. 2025; 96(4):314-321.

Introduction: Facial hair is prohibited for most airline pilots because of the widespread belief that the seal on oxygen masks might be rendered ineffective, preventing aircrew from performing their duties during emergencies.

Methods: Continuous oximetry recordings were made every second from 24 volunteers wearing a standard commercial airline mask in 1 of 3 beard conditions: no beards, short beards (<10 mm in length), and long beards (>10 mm in length) in a normobaric hypoxia chamber at 30,000 ft (10,000 m). Masks were worn in the chamber for about 10 min before being removed for about 2 min to experience hypoxia. Once returned to normoxia, volunteers were exposed to smelling salts held directly under the chin.

Results: None of the beard conditions differed in the time to don the masks. There were no differences in the arterial saturation percent of oxygen (Spo2) between beard conditions for either mask-on or mask-off segments in the chamber. There were significant differences in Spo2 between the mask-on segment and the mask-off segment, indicating that hypoxemic conditions would have been detected had the masks been ineffective.

Discussion: Using a current on-demand airline oxygen mask, Spo2 levels were never compromised by any of the beard conditions. Because the highly volatile smelling salts were imperceptible through the masks, smoke and other noxious irritants would not be perceived. These results support the contention that airline pilots with beards of any length would not be impaired by hypoxia or smoke while dealing with an in-flight emergency. French J, Wagner SD. Beard length and the efficacy of an aviator oxygen mask. Aerosp Med Hum Perform. 2025; 96(4):322-326.