INTRODUCTION: The exercise electrocardiogram (ExECG), or stress test, is a widely used screening tool in occupational medicine designed to detect occult coronary artery disease, and assess performance capacity and cardiovascular fitness. In some guidelines, it is recommended for high-risk occupations in which occult disease could possibly endanger public safety. In aviation medicine, however, there is an ongoing debate on the use and periodicity of ExECG for screening of aircrew.METHOD: In the German Armed Forces, aircrew applicants and active-duty aircrew undergo screening ExECG. We analyzed 7646 applicant ExECGs (5871 from pilot and 1775 from nonpilot applicants) and 17,131 ExECGs from 3817 active-duty pilots. All were performed at the German Air Force Centre of Aerospace Medicine (GAFCAM) and analyzed for ECG abnormalities, performance capacity, blood pressure, and heart rate response.RESULTS: Only 15/5871 (0.2%) of pilot applicants required further investigation and none were ultimately disqualified for aircrew duties due to their ExECG results. Of the nonpilot applicants, 22/1775 (1.2%) required further diagnostic work-up due to their ExECG findings, with only 1 ultimately disqualified. From active-duty pilots, 84/17,131 (0.5%) ExECGs revealed findings requiring further investigation, with only 2 pilots ultimately disqualified from flying duties.DISCUSSION: The extremely low yield of ExECG findings requiring further evaluation and/or disqualification for aircrew duties suggest its use is questionable and not cost-effective as a screening tool in this cohort. It may be enough to perform ExECG on clinical indication alone.Guettler N, Nicol ED, Sammito S. Exercise ECG for screening in military aircrew. Aerosp Med Hum Perform. 2022; 93(9):666–672.

BACKGROUND: Astronauts on the mission to Mars will be subjected to galactic cosmic radiation (GCR) exposures. While ground-based studies suggest that simulated GCR (GCRsim) exposure impairs performance in multiple cognitive tasks, the impact of such exposures on task switching performance (an important skill for all aviators) has not yet been determined.METHODS: Male Wistar rats previously exposed to 10 cGy of ⁴He ions or GCRsim and their sham littermates were trained to perform a touchscreen-based switch task designed to mimic warning light response tests used to evaluate pilots’ response times.RESULTS: Irradiated rats failed to complete a high cognitive task load training task threefold more frequently than shams. There were 18 (4 Sham, 7 He-, and 7 GCR-exposed) rats that successfully completed initial training and underwent switch task testing. Relative to the sham rats in the switch task, the GCRsim-exposed rats had significantly slower response times in switch but not repeat trials. The GCRsim-exposed rats had significantly (P < 0.01) higher switch response ratios (switch/repeat trial response time) and absolute switch costs (switch minus repeat trial response time) than either the sham or He-exposed rats.DISCUSSION: Rats exposed to GCRsim have significantly impaired performance in the switch task manifested as an absolute switch cost of ∼700 ms. The operational significance of such an increase requires further investigation, but a 1000-ms switch cost results in a twofold increase in cockpit error rates in pilots. If exposure to GCR in space results in similar effects in humans, the operational performance of astronauts on the Mars mission may be suboptimal.Stephenson S, Britten R. Simulated space radiation exposure effects on switch task performance in rats. Aerosp Med Hum Perform. 2022; 93(9):673–680.

INTRODUCTION: Physiological episodes are an issue in military aviation. Some non-pressure-related in-flight symptoms are proved to be due to hyperventilation rather than hypoxia. The aim of this study was to validate a new training method provoking hyperventilation during normobaric hypoxia (NH) training in an F/A-18 Hornet simulator.METHODS: In a double-blind setting, 26 fighter pilots from the Finnish Air Force performed 2 setups in a WTSAT simulator in randomized order with full flight gear. Without the pilot's knowledge, 6% O₂ in nitrogen or 6% O₂ + 4% CO₂ in nitrogen was turned on. Ventilation (VE) was measured before, during, and after hypoxia. S_po₂ and ECG were monitored and symptoms documented. The subjects performed a tactical identification flight until they recognized symptoms of hypoxia. Thereafter, they performed hypoxia emergency procedures with 100% O₂ and returned to the base with a GPS malfunction and executed an instrument landing system (ILS) approach with the waterline HUD mode evaluated by the flight instructor on a scale of 1 to 5.RESULTS: Ventilation increased during normobaric hypoxia (NH) from 12 L · min⁻¹ to 19 L · min⁻¹ at S_po₂ 75% with 6% O₂, and from 12 L · min⁻¹ to 26 L · min⁻¹ at S_po₂ 77% with 6% O₂ + 4% CO₂. ILS flight performance was similar 10 min after combined hyperventilation and hypoxia (3.1 with 6% O₂ + 4% CO₂ and 3.2 with 6% O₂). No adverse effects were reported during the 24-h follow-up.DISCUSSION: Hyperventilation-provoking normobaric hypoxia training is a new and well-tolerated method to meet NATO Standardization Agreement hypoxia training requirements.Leinonen AM, Varis NO, Kokki HJ, Leino TK. A new method for combined hyperventilation and hypoxia training in a tactical fighter simulator. Aerosp Med Hum Perform. 2022; 93(9):681–687.

INTRODUCTION: Sympathetic stimulation is known to be associated with transient alterations of blood glucose (BG) concentration; spaceflight acceleration may be similarly associated with alterations of BG, potentially posing a risk to diabetic individuals engaging in future spaceflight activities. Despite prior studies demonstrating diabetic subjects’ tolerance to centrifuge-simulated spaceflight, data are lacking regarding blood glucose response to hypergravity. It remains unclear whether hypergravity or associated physiological response may pose a risk to diabetics. Continuous glucose monitors (CGM) offer a means of noninvasive glucose monitoring and may be useful in spaceflight and analog environments. Here, we describe the results of continuous glucose monitoring during centrifuge-simulated spaceflight.METHODS: Subjects participated in 1–5 centrifuge-simulated spaceflight profiles (maximum +4.0 G_z, +6.0 G_x, 6.1 G resultant). Data collection included heart rate, blood pressure, electrocardiogram, continuous glucose via CGM, intermittent fingerstick BG, and postrun questionnaires regarding symptoms related to hypergravity exposure.RESULTS: CGM data were collected from 26 subjects, including 4 diabetics. While diabetic subjects had significantly higher BG compared to nondiabetics, this was not associated with any difference in symptoms or tolerance. Transient hypergravity-associated CGM glucose alterations did not affect tolerance of the centrifuge experience. CGM data were found to be reliable with occasional exceptions, including four instances of false critical low glucose alarms.DISCUSSION: While further study is necessary to better characterize CGM fidelity during hypergravity and other spaceflight-related stressors, CGM may be a feasible option for spaceflight and analog settings. As in prior studies, individuals with well-controlled diabetes appear able to tolerate the accelerations anticipated for commercial spaceflight.Ong KM, Rossitto JJ, Ray K, Dufurrena QA, Blue RS. Blood glucose alterations and continuous glucose monitoring in centrifuge-simulated spaceflight. Aerosp Med Hum Perform. 2022; 93(9):688–695.

INTRODUCTION: Pilots’ mental health has received increased attention following Germanwings Flight 9525 in 2015, where the copilot intentionally crashed the aircraft into the French Alps, killing all on board. An investigation of this incident found that the pilot had a depressive disorder.METHODS: This systematic review investigated peer reviewed studies of pilot mental health published since 1980. A total of 58 papers were identified.RESULTS: Two main methodologies have been employed: questionnaires and database record searches. Anxiety, depression, and suicide were the most commonly investigated mental health conditions. There were almost an equal number of studies that found a higher prevalence of psychological symptoms in pilots as those that found a lower prevalence, relative to controls or the general population. Prevalence rates were higher in studies relying solely on questionnaires than in studies employing database record searches.DISCUSSION: Prevalence estimates are closely associated with methodology, so it is difficult to determine the true rate. Factors that might account for low prevalence estimates include under-reporting of symptoms by pilots and a reluctance to diagnose on the part of health professionals. Factors that might account for high prevalence estimates include anonymous assessment, the use of questionnaires that do not align with clinical disorders, and inconsistent cut-off scores. It is recommended that future studies on prevalence use well-validated clinical measures, and that more research be conducted on the effects of particular disorders on job performance.Ackland CA, Molesworth BRC, Grisham JR, Lovibond PF. Pilot mental health, methodologies, and findings: a systematic review. Aerosp Med Hum Perform. 2022; 93(9): 696–708.

Shaw DM, Henderson L, van den Berg M. Cognitive, sleep, and autonomic responses to induction of a ketogenic diet in military personnel: a pilot study. Aerosp Med Hum Perform. 2022; 93(6):507516.In the article by Shaw et al., the publishers neglected to include the author corrections to the manuscript. The corrected manuscript is available through the online journal on Ingenta at: <ext-link ext-link-type="uri" xlink:href="https://www.ingentaconnect.com/contentone/asma/amhp/2022/00000093/00000006/art00007">https://www.ingentaconnect.com/contentone/asma/amhp/2022/00000093/00000006/art00007</ext-link>.Those corrections that affect the study directly are published in this erratum. We sincerely apologize for this error and the inconvenience it has caused.