Cognitive performance of air personnel following sleep deprivation.

Air forces have developed several methods for reducing fatigue-related accidents. In the Israeli Air Force, the "Dead Tired" workshop was developed with the purpose of presenting aircrew with their objective performance under sleep deprivation conditions. The aim of this study was to examine the cognitive abilities of both aircrew and unmanned aerial vehicle operators, both objectively and subjectively. All Israeli aircrew and unmanned aerial vehicle operators participated in a "Dead Tired" workshop. During the workshop, the participants performed the Psychomotor Vigilance Task, a task that tests their attention abilities, while gathering information on their subjective sleepiness in the form of a Karolinska Sleepiness Scale. Data of 366 participants (25 females), of whom 187 were unmanned aerial vehicle operators and 179 were aircrew, were obtained; and the mean age was 21.8 ± 1.2 years (range 19-26 years). A significant decline in task performance was seen following 20 hr of wakefulness in both unmanned aerial vehicle operators and aircrew (p < 0.001). Unmanned aerial vehicle operators' performance was significantly better throughout the majority of the workshop (p < 0.001). Recovery after the full-night's sleep was seen for unmanned aerial vehicle operators, but not for aircrew (p = 0.008). A high correlation was seen between Psychomotor Vigilance Task performance and Karolinska Sleepiness Scale responses (correlation coefficient = 0.93). Sleep deprivation negatively impacted the performance of both groups of participants. Unmanned aerial vehicle operators were found to be more resilient to the effects of sleep deprivation and were quicker to recover in comparison to aircrew.

Anticholinergic Versus Antihistaminic Treatment for Simulator Sickness Prevention.

Flight simulators have an essential role in aircrew training. Occasionally, symptoms of motion sickness, defined as simulator sickness, develop during these sessions. Preventive methods for motion sickness have been investigated thoroughly; however, only a few studies have examined preventive treatments for simulator sickness. The aim of this study was to examine the efficacy of scopolamine (an anticholinergic drug) compared with cinnarizine (an antihistaminic drug) for helicopter simulator sickness prevention. A validated simulator sickness questionnaire (SSQ) score was used to determine the severity of simulator sickness symptoms in this study. Preliminary SSQ scores and SSQ scores after each sortie were calculated. Each participant was given scopolamine, cinnarizine, or a placebo in a double-blind randomized manner before the first sortie of each training day. Forty-one helicopter pilots participated in the trial. The average age was 30.5 ± 7.1 years. SSQ values significantly improved from an average of 73.30 in the preliminary SSQ questionnaire to an average of 30.92 after 2 hours following the administration of cinnarizine (P = .012, 95%CI 8.071-76.703). Scopolamine was found to be less effective than both cinnarizine and the placebo in the alleviation of simulator sickness symptoms. This study is the first to compare scopolamine with cinnarizine for simulator sickness prevention. Based on the results of this study, we recommend the use of cinnarizine over scopolamine for simulator sickness prevention.

Is There an Association between BMI, Height, and Gender and Long-Bone Fractures during Childhood and Adolescence? A Large Cross-Sectional Population Study of 911,206 Subjects.

INTRODUCTION: Traumatic long-bone fractures (TLFs) among children and adolescents are relatively common, with morbidity and economic consequences. Obesity has become a significant global concern. Studies have found an association between TLFs and BMI in the past but not in a large cross-sectional population study. Our study objective was to measure the incidence of TLFs in the 17-year-old general population and evaluate its association with BMI, body height, and gender. METHODS: Data from a medical database containing all 17-year-old candidates' records before recruitment into mandatory military service were retrieved as BMI, height, gender, and history of TLFs. Logistic regression models assessed the association between BMI and height to TLFs. RESULTS: The records of 911,206 subjects (515,339 males) were reviewed. In total, 9.65% had a history of TLFs (12.25% and 6.25% for males/females, respectively). Higher BMI was associated with TLF, with a linear trend in the odds ratio (OR) for having TLFs. The strongest association was found between obese females and TLFs (OR = 1.364, p < 0.0001). Height was an independent factor positively associated with TLFs. The OR for a TLF in the highest height quintile was 1.238 (p < 0.001) for males and 1.411 (p < 0.001) for females compared to the lowest quintile. Although TLFs were more common in males, the OR for TLFs was more prominent in females. CONCLUSIONS: There is an association between BMI, body height, and TLFs in healthy adolescents. TLFs are more common in males, but the strongest association between overweight and obesity is evident in females.

Negative impact of high-performance flights on aviators with mitral valve prolapse.

BACKGROUND: While it appears not to affect healthy aviators' hearts, there are scarce data regarding the impact of high-performance flights on aviators with mitral valve prolapse (MVP). METHODS: A retrospective, comparative cohort study of military aviators with MVP. Subjects were categorized to either high-performance (jet fighter) or low-performance (transport and helicopter) aviators. The primary outcomes were the rates of mitral interventions and of adverse cardiovascular events since being an aircrew candidate and up to the end of flying career. Additional outcomes were echocardiographic measurements and the cumulative proportion of mitral valve interventions over time. RESULTS: Of 33 male aviators with MVP, 18 were high-performance aviators. On average, follow-up started at age 18.5 years and lasted 27.8 ±â€¯10.1 years. Baseline characteristics were similar between the study groups. Aviators of high-performance aircraft had increased rates of mitral valve surgery (33 % vs. 0, p = 0.021), MVP-related complications (39 % vs. 6.7 %, p = 0.046), and a higher incidence of mitral valve repair over time (p = 0.02). High-performance flight was associated with increased intraventricular septum thickness (IVS, 9.7 mm vs 8.9 mm, p = 0.015) and IVS index (p = 0.026) at the last echocardiographic assessment. High-performance aviators tended to develop worsening severity of mitral regurgitation. CONCLUSIONS: High-performance flight may be associated with an increased risk for valvular deterioration and need for mitral surgery in aviators with MVP.

Symptomatic Joint Hypermobility Is Associated with Low Back Pain: A National Adolescents Cohort Study.

Background: Low back pain (LBP) is a widespread medical complaint affecting many people worldwide and costing billions. Studies suggest a link between LBP and joint hypermobility. This study aimed to examine the association between symptomatic joint hypermobility (SJH), LBP, and gender. Methods: Data were obtained from a medical database containing 17-year-old candidates' records before recruitment into mandatory military service. According to the Regulations of Medical Fitness Determination, information on disability codes associated with LBP and SJH was retrieved. Results: According to this national survey, the prevalence of SJH is 0.11% (1355 cases out of 1,220,073 subjects). LBP was identified in 3.7% of the cohort (44,755 subjects). Subjects were further subdivided into LBP without objective findings (LBPWF) (3.5%) and LBP with objective findings (LBPOF) (0.2%). The association between SJH and LBP was examined: the Odds Ratio (OR) was 2.912 (p < 0.0001). The odds rations for LBPWF and LBPOF were further calculated to be 2.914 (p < 0.000) and 2.876 (p < 0.000), respectively. Subjects with SJH were almost three times more prone to LBPWF and LBPOF. Conclusion: SJH is strongly associated with LBP in young adults. Further pathophysiological research is needed.

Medically Disqualifying Conditions Among Aircrew Candidates.

BACKGROUND: Medical selection criteria for Israeli Air Force (IAF) Flight Academy candidates are strict due to the extreme physiological stressors during military flight. In various air forces the causes for medical disqualification of Flight Academy candidates are different, mainly due to differences in the selection process and criteria. In the present study, we examined the medical conditions leading to disqualification of candidates for the IAF Flight Academy.METHODS: We reviewed the medical records of 3281 military Flight Academy candidates who underwent medical evaluation in the IAF Aeromedical Center between June 2016 and March 2018. For each disqualified candidate, we examined the cause or causes for disqualification divided into categories.RESULTS: Out of 3281 Flight Academy candidates, 519 candidates (15.8%) were disqualified. The most prevalent cause for disqualification were ophthalmological conditions, which constituted more than half of the disqualifications (55.0%). Among the ophthalmological conditions, nonsatisfactory visual acuity constituted more than half (57.4%). The following most prevalent causes were asthma (7.9%), allergic rhinitis (7.3%), renal and urinary conditions, and otolaryngologic conditions (5.2% each).DISCUSSION: The leading cause for disqualification of Flight Academy candidates was ophthalmological conditions, similar to other air forces. Our findings warrant an ongoing review of criteria for disqualification.Groner O, Frenkel-Nir Y, Erlich-Shoham Y, Shoval G, Gordon B. Medically disqualifying conditions among aircrew candidates. Aerosp Med Hum Perform. 2022; 93(4):384-389.

Myocarditis following COVID-19 vaccination - A case series.

There have been reports of myocarditis following COVID-19 vaccination. We surveyed all hospitalized military personnel in the Isareli Defense Forces during the period of the COVID-19 vaccination operation (12/28/2021-3/7/2021) for diagnosed myocarditis. We identified 7 cases of myocarditis with symptoms starting in the first week after the second dose of COVID-19 Pfizer-BioNTech vaccine. One case of myocarditis diagnosed 10 days after the second dose of the vaccine was not included. These 8 cases comprise of all events of myocarditis diagnosed in military personnel during this time period. All patients were young and generally healthy. All had mild disease with no sequalae. The incidence of myocarditis in the week following a second dose of the vaccine was 5.07/100,000 people vaccinated. Due to the nature of this report no causality could be established. Clinicians should be aware of the possibility of myocarditis following Pfizer-BioNTech vaccination. True incidence rates should be further investigated.

Self-reported symptoms in healthy young adults to predict potential coronavirus disease 2019.

OBJECTIVE: To assess the utility of self-reported symptoms in identifying positive coronavirus disease 2019 (COVID-19) cases among predominantly healthy young adults in a military setting. METHODS: A questionnaire regarding COVID-19 symptoms and exposure history was administered to all individuals contacting the Israeli Defence Forces Corona call-centre, before PCR testing. Surveyed symptoms included cough, fever, sore throat, rhinorrhoea, loss of taste or smell, chest pain and gastrointestinal symptoms. Factors were compared between positive and negative cases based on confirmatory test results, and positive likelihood ratios (LR) were calculated. Results were stratified by sex, body mass index, previous medical history and dates of questioning, and a multivariable analysis for association with positive test was conducted. RESULTS: Of 24 362 respondents, 59.1% were men with a median age of 20.5 years (interquartile range 19.6-22.4 years). Significant positive LRs were associated with loss of taste or smell (LR 3.38, 95% CI 3.01-3.79), suspected exposure (LR 1.33, 95% CI 1.28-1.39) and fever (LR 1.26, 95% CI 1.17-1.36). Those factors were also associated with positive PCR result in a multivariable analysis (OR 3.51, 95% CI 3.04-4.06; OR 1.86, 95% CI 1.65-2.09; and OR 1.34, 95% CI 1.19-1.51, respectively). Reports of loss of taste or smell increased gradually over time and were significantly more frequent during the late period of the study (63/5231, 1.21%; 156/7941, 1.96%; and 1505/11 190, 13.45%: p < 0.001). CONCLUSION: Loss of taste or smell, report of a suspicious exposure and fever (>37.5°C) were consistently associated with positive LRs for a positive SARS-CoV-2 PCR test result, in a population of predominantly young and healthy adults.

Injuries associated with the use of ejection seats: a systematic review, meta-analysis and the experience of the Israeli Air Force, 1990-2019.

INTRODUCTION: All modern military jet aircraft are equipped with rocket-assisted ejection systems. Jet aircraft operate in the majority of the conflict regions throughout the world, and in nearly all modern countries during peacetime. Civilian and military emergency services may be called upon to treat aircrews that have ejected and should be familiar with the common injury patterns associated with aircraft ejection. METHODS: A systematic review and meta-analysis of the literature were undertaken using the preferred reporting for systematic reviews and meta-analyses (PRISMA) methodology. Peer-reviewed journal and conference papers published between 1 January 1971 and 15 June 2019 were included. Our primary outcomes of interest were mortality and major injury rates. The I2 test was used to assess heterogeneity among the included studies, and data were pooled under random effects models. In addition, all ejection cases in the Israeli Air Force (IAF) between 1990 and 2019 were studied. The data were manually extracted from the accident records and the electronic medical records system. RESULTS: We identified 14 studies that included 1710 aircrew ejections. Heterogeneity was high (I2>75%). Pooled mean mortality and major injury rates were 10.5% (95% CI 6.8-14.8%) and 29.8% (95% CI 20.1-40.6%), respectively. The major injuries included spinal fractures (61.6%), extremity trauma (27.3%), and head trauma (8.9%). During the IAF study period, a total of 37 aircrew ejected from 26 IAF aircraft. The fatality rate was 5.4% and 18.9% suffered major injuries. CONCLUSIONS: Although ejection is lifesaving, it is associated with unique injury patterns that should be addressed during clinical evaluation. Because of their high prevalence, spinal precautions are paramount until spinal injury can be ruled out, generally by advanced imaging. Looking forward, injury patterns will continue to evolve in parallel with improving ejection seat systems.

Myopia and Childhood Migration: A Study of 607 862 Adolescents.

PURPOSE: Immigration studies can shed light on myopia development and reveal high-risk populations. To this end, we investigated the association among immigration, age at immigration, and myopia occurrence during adolescence. DESIGN: Population-based, retrospective, cross-sectional study. PARTICIPANTS: Six hundred seven thousand eight hundred sixty-two adolescents, Israeli born and immigrants, with origins in the former Union of Soviet Socialist Republics (USSR), Ethiopia, or Israel, assessed for medical fitness for mandatory military service at 17 years of age between 1993 and 2016. METHODS: Myopia and high myopia were defined based on right eye refractive data. Age at immigration was categorized into 0 to 5 years of age, 6 to 11 years of age, and 12 to 19 years of age. Univariate and multivariate logistic regression models were created. Myopia odds ratios (ORs) were calculated according to immigration status, with Israeli-born natives as controls. Next, myopia ORs were calculated according to age at immigration, with Israeli-born of same origin as controls. MAIN OUTCOME MEASURES: Myopia prevalence and ORs. RESULTS: Myopia was less prevalent among immigrants than Israeli-born controls. When stratified according to age at immigration, a decrease in myopia prevalence and ORs with increasing age at migration were observed, most prominent in immigrants arriving after 11 years of age, who also showed lower high-myopia ORs. The immigrants from the USSR and Ethiopia arriving after 11 years of age showed a myopia OR of 0.65 (95% confidence interval [CI], 0.63-0.67; P < 10-205) and 0.52 (95% CI, 0.46-0.58; P < 10-27) compared with the Israeli-born controls. Notably, Ethiopians arriving earlier than 5 years of age showed a 2-fold higher myopia OR than those migrating after 11 years of age. CONCLUSIONS: Immigrants arriving after 11 years of age showed markedly lower ORs for myopia and high myopia relative to Israeli-born controls or those arriving during early childhood, likely because of environmental and lifestyle changes. Differences between immigrants arriving up to 5 years of age and those arriving between 6 and 11 years of age were relatively smaller, suggesting exposures at elementary school age play a greater role in this population.

Success Rates at an Air Force Pilot Academy and Its Relation to Methylphenidate Use.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a chronic neurological disorder characterized by persistent patterns of inattention, impulsivity, and hyperactivity. The most common treatment for this disorder is methylphenidate, which is a disqualifying medication for flight. Candidates with previous use of methylphenidate are not necessarily disqualified from the Israeli Air Force (IAF) flight academy.METHODS: Flight cadets from 12 consecutive flight courses who have used methylphenidate at least once in the past were identified according to their medical records. The graduation ratio of cadets with previous use of methylphenidate was compared with that of the rest of the cadets. A comparison was also made with regard to the causes of disqualification from the flight course. Statistical significance was assessed using the Fischer Test.RESULTS: Among the 90 flight cadets who have used methylphenidate, only 2 (2.2%) successfully graduated from the IAF flight academy. Among the 2983 flight cadets who have no history of methylphenidate use, 461 (15.4%) successfully graduated. We found no significant differences in the disqualification causes between the two groups.CONCLUSION: The IAF flight academy graduation rate was meaningfully and significantly lower among cadets who reported previous use of methylphenidate. The study design, however, limits the inference of causal relationship.Sarfati S, Nakdimon I, Tsodyks J, Assa A, Gordon B. Success rates at an air force pilot academy and its relation to methylphenidate use. Aerosp Med Hum Perform. 2019; 90(9):788-791.

Adherence to antidepressant medications is associated with reduced premature mortality in patients with cancer: A nationwide cohort study.

BACKGROUND: Depression and anxiety are common in cancer and antidepressants (AD) are efficacious treatment. The relationship between AD adherence and mortality in cancer is unclear. This study aimed to evaluate the association between adherence to AD and all-cause mortality in a population-based cohort of patients with cancer. MATERIALS AND METHODS: We conducted a 4-year historical prospective cohort study including 42,075 patients with cancer who purchased AD at least once during the study period. Adherence to AD was modeled as nonadherence (<20%), poor (20-50%), moderate (50-80%), and good (>80%) adherence. We conducted multivariable survival analyses adjusted for demographic and clinical variables that may affect mortality. RESULTS: During 1,051,489 person-years at risk follow-up, the adjusted hazard ratios (HR) for mortality were 0.89 (95% confidence interval [CI]: 0.83-0.95), 0.77 (95% CI: 0.66-0.72), and 0.80 (95% CI: 0.76-0.85) for the poor, moderate, and good adherence groups, respectively, compared to the nonadherent group. Analysis of the entire sample and a subgroup with depression, for cancer subtypes, revealed similar patterns for breast, colon, lung, and prostate cancers, but not for melanoma patients. Multivariate predictors of premature mortality included male gender (HR 1.48 [95% CI: 1.42-1.55]), current/past smoking status (HR 1.1, [95% CI: 1.04-1.15]; P < .0001), low socioeconomic status (HR 1.1, [95% CI: 1.03-1.17]; P < .0001) and more physical comorbidities. CONCLUSIONS: The present study is the first to demonstrate that higher adherence to AD is associated with a decrease of all-cause mortality in a large nationwide cohort of cancer patients. Our data add to the pressing need to encourage adherence to AD among cancer patients.

Hypertension and childhood migration: a nationwide study of 2.7 million adolescents.

OBJECTIVES: Immigration studies can shed light on hypertension development and reveal high-risk populations. To this end, we investigated the association between age at immigration and hypertension occurrence at adolescence among immigrants to Israel. METHODS: We analyzed cross-sectional data on 2 681 294 adolescents assessed for mandatory military service at approximately 17 years of age between 1967 and 2016. The study population constituted of 410 488 immigrants with origins in Ethiopia, Middle East and North Africa, Former USSR and Western Countries. Age at immigration was categorized into 0-5, 6-11 and 12-19 years. Odds ratios (ORs) for hypertension were calculated according to age at immigration with Israel-born participants as controls. Models were made to account for possible confounders. Additionally, the study population was stratified by country of origin and each immigrant group referenced to Israel-born participants of the same origin. RESULTS: In the fully-adjusted model, immigrants arriving until age 11 years had comparable ORs for hypertension to the Israeli-born reference group, whereas recent immigrants, arriving at age 12-19 years had a marked lower OR of 0.30 (95% CI 0.27-0.33; P < 0.001). The lower hypertension odds among recent immigrants persisted in all models and when the study sample was stratified by sex and origin, with all but those of Western origin showing a graded decrease with increasing age at migration categories. CONCLUSION: Immigrants arriving earlier in childhood lose their protection against hypertension at adolescence relative to the Israeli-born, likely because of lifestyle acculturation. Prevention programs are needed, beginning upon arrival and placing emphasis on nutritional and physical activity habits.

Coronal Knee Malalignment in Young Adults and Its Link to Body Measures.

Our aim was to report the prevalence of knee varus-valgus malalignment (KVVM) and its association with body mass index (BMI) and body height in a healthy and fit young adult population. Information on the disability codes associated with KVVM according to the Regulations of Medical Fitness Determination was retrieved from a medical database containing records of 17-year-old males and females before their recruitment into mandatory military service. Logistic regression models assessed the association between the BMI and body height to KVVM. The study cohort included 821,381 subjects (460,674 males and 360,707 females). The prevalence of KVVM was 0.9% in males and 0.6% for females. Under/overweight subjects were associated with higher prevalence of KVVM. The odds ratios (ORs) had a "J" curve pattern, increasing for underweight males and females, and even more so for above-normal BMIs (for obese males and for both overweight and obese females). The strongest association was between obese females and KVVM: an obese female had an OR of 22.864 (confidence interval [CI] = 20.683-25.725, p < 0.001) to have KVVM and an obese male had an OR of 4.483 (CI = 4.158-4.833 p < 0.001). When the BMI was analyzed as a continuous variable, each increase in one BMI unit was associated with an increase in OR of 7.6% for males and 24.1% for females. There is a strong association between BMI and KVVM in both underweight and overweight young adults. KVVM is more common in males, but most strongly associated with overweight and obese females.This is a Level III, case-control study.

Aviator's Fluid Balance During Military Flight.

INTRODUCTION: A loss of 1% or more of bodyweight due to dehydration has a negative effect on cognitive performance, which could critically affect flight safety. There is no mention in the literature concerning the amounts of military pilots' fluid loss during flight. The aim of this study was to quantify fluid loss of pilots during military flight. METHODS: There were 48 aviators (mean age 23.9) from the Israeli Air Force who participated in the study, which included 104 training flights in various flight platforms. Bodyweight, urine specific gravity, and environmental heat strain were measured before and after each flight. Fluid loss was calculated as the weight differences before and after the flight. We used a univariate and one-way ANOVA to analyze the effect of different variables on the fluid loss. RESULTS: The mean fluid loss rate was 462 ml · h-1. The results varied among different aircraft platforms and depended on flight duration. Blackhawk pilots lost the highest amount of fluids per flight, albeit had longer flights (mean 108 min compared to 35.5 in fighter jets). Jet fighter pilots had the highest rate of fluid loss per hour of flight (up to 692 ml, extrapolated). CONCLUSION: Overall, at 11 flights (11%) aircrew completed their flight with a meaningful fluid loss. We conclude that military flights may be associated with significant amount of fluid loss among aircrew.Levkovsky A, Abot-Barkan S, Chapnik L, Doron O, Levy Y, Heled Y, Gordon B. Aviator's fluid balance during military flight. Aerosp Med Hum Perform. 2018; 89(2):9498.

Vision improvement in pilots with presbyopia following perceptual learning.

Israeli Air Force (IAF) pilots continue flying combat missions after the symptoms of natural near-vision deterioration, termed presbyopia, begin to be noticeable. Because modern pilots rely on the displays of the aircraft control and performance instruments, near visual acuity (VA) is essential in the cockpit. We aimed to apply a method previously shown to improve visual performance of presbyopes, and test whether presbyopic IAF pilots can overcome the limitation imposed by presbyopia. Participants were selected by the IAF aeromedical unit as having at least initial presbyopia and trained using a structured personalized perceptual learning method (GlassesOff application), based on detecting briefly presented low-contrast Gabor stimuli, under the conditions of spatial and temporal constraints, from a distance of 40 cm. Our results show that despite their initial visual advantage over age-matched peers, training resulted in robust improvements in various basic visual functions, including static and temporal VA, stereoacuity, spatial crowding, contrast sensitivity and contrast discrimination. Moreover, improvements generalized to higher-level tasks, such as sentence reading and aerial photography interpretation (specifically designed to reflect IAF pilots' expertise in analyzing noisy low-contrast input). In concert with earlier suggestions, gains in visual processing speed are plausible to account, at least partially, for the observed training-induced improvements.

Influenza Season Hospitalization Trends in Israel: A Multi-Year Comparative Analysis 2005/2006 Through 2012/2013.

BACKGROUND: Influenza-related morbidity impacts healthcare systems, including hospitals. OBJECTIVE: To obtain a quantitative assessment of hospitalization burden in pediatric and internal medicine departments during influenza seasons compared with the summer months in Israel. METHODS: Data on pediatric and internal medicine hospitalized patients in general hospitals in Israel during the influenza seasons between 2005 and 2013 were analyzed for rate of hospitalizations, rate of hospitalization days, hospital length of stay (LOS), and bed occupancy and compared with the summer months. Data were analyzed for hospitalizations for all diagnoses, diagnoses of respiratory or cardiovascular disease (ICD9 390-519), and influenza or pneumonia (ICD9480-487), with data stratified by age. The 2009-2010 pandemic influenza season was excluded. RESULTS: Rates of monthly hospitalizations and hospitalization days for all diagnoses were 4.8% and 8% higher, respectively, during influenza seasons as compared with the summers. The mean LOS per hospitalization for all diagnoses demonstrated a small increase during influenza seasons as compared with summer seasons. The excess hospitalizations and hospitalization days were especially noticed for the age groups under 1 year, 1-4 years, and 85 years and older. The differences were severalfold higher for patients with a diagnosis of respiratory or cardiovascular disease and influenza or pneumonia. Bed occupancy was higher during influenza seasons compared with the summer, particularly in pediatric departments. CONCLUSIONS: Hospital burden in pediatric and internal medicine departments during influenza seasons in Israel was associated with age and diagnosis. These results are important for optimal preparedness for influenza seasons.

Immigration to Israel during childhood is associated with diabetes at adolescence: a study of 2.7 million adolescents.

AIMS/HYPOTHESIS: Immigration studies can shed light on diabetes pathogenesis and risk factors. To this end, we investigated the association between age at immigration and diabetes occurrence at adolescence among immigrants to Israel. METHODS: We analysed cross-sectional data on 2,721,767 Jewish adolescents assessed for mandatory military service at approximately 17 years of age between 1967 and 2014. The study population comprised 430,176 immigrants with origins in Ethiopia, former USSR, Middle East and North Africa (ME/NA) and western countries. ORs for diabetes were calculated for men and women, grouped according to age at immigration, with Israel-born participants as controls. Unadjusted and fully adjusted models were made to account for possible confounders. Additionally, the study population was stratified by origin and each immigrant group was referenced to Israel-born participants of the same origin. RESULTS: There was a graded decrease in OR for diabetes across the study groups in the fully adjusted model. Immigrants arriving at age 0-5 years had comparable OR for diabetes to the Israeli-born reference group; those arriving at age 6-11 years had an OR of 0.82 (95% CI 0.70, 0.97; p = 0.017) and recent immigrants, arriving at age 12-19 years, had the lowest OR of 0.65 (95% CI 0.54, 0.77; p < 0.0001). When age at immigration was treated as a continuous variable, there was an adjusted risk for occurrence of diabetes of 0.97 (95% CI 0.96, 0.99; p = 0.001) for every year increment. The lower risk for diabetes among recent immigrants persisted in the unadjusted model and persisted when the study sample was stratified by sex and origin, except for immigrants arriving from ME/NA. Notably, Ethiopians born in Israel had a sixfold higher diabetes crude prevalence than Ethiopian immigrants arriving after the age of 5 years. CONCLUSIONS/INTERPRETATION: Immigrants of different ethnic groups arriving earlier in childhood lose their protection against diabetes at adolescence, relative to children born in Israel. This is perhaps due to environmental and lifestyle changes, especially those beginning at an early age.