COVID-19 vaccination - Does it affect sick leave in military personnel?

OBJECTIVE: Sick leave is a major negative economic effect of the COVID-19 pandemic. In April 2021, the Integrated Benefits Institute reported that employers spent a total of US $50.5 billion for workers absent due to the COVID-19 pandemic. While vaccination programs lowered the number of severe illness and hospitalizations worldwide, the number of side effects following vaccination against COVID-19 were high. The present study aimed to evaluate the effect of vaccination on the probability of taking sick leave in the week following vaccination. SUBJECTS AND METHODS: The study population was comprised of all personnel serving in the Israel Defense Forces (IDF) between October 7, 2020, and October 3, 2021, (a total of 52 weeks) who were vaccinated with at least one dose of the BNT162b2 vaccine. Data on Israel Defense Forces (IDF) personnel sick leaves were retrieved and the probability of a "post-vaccination week sick leave" and a "regular (not post-vaccination week) sick leave" were analyzed. An additional analysis was performed to determine whether winter-related diseases or the sex of the personnel affected the probability of taking sick leave. RESULTS: The probability of taking sick leave in a post-vaccination week was significantly higher than the probability of taking sick leave in a regular week (8.45% vs. 4.3%, respectively, p < 0.01). The increased probability remained unchanged after analysis of sex-related and winter disease-related variables. CONCLUSIONS: Given the major effect of vaccination against COVID-19 by BNT162b2 vaccine on the probability of taking sick leave, when medically feasible, the timing of the vaccination should be considered by medical, military, and industrial authorities with the intent to minimize the effect on overall national economy and safety.

Predictors of combat training attrition in Israel Defense Forces soldiers.

BACKGROUND: Attrition from combat service carries significant organizational and personal ramifications, but predicting factors associated with attrition remains challenging. AIMS: To evaluate medical and psychosocial factors associated with attrition from basic combat training (BCT) in the Israel Defense Forces (IDF). In addition, we identify subsets of the recruit population which exhibit certain trends in terms of medical corresponding with a high risk of attrition. METHODS: A cross-sectional study of IDF combat trainees undergoing infantry BCT between 2012 and 2017. Data were collected from the soldiers' electronic medical and administrative records. We used multivariable logistic regression and the SAS® decision-tree tool to analyse key predictive factors for attrition. RESULTS: A total of 46 472 soldiers enlisted to BCT during the research period. The mean body mass index (BMI) was 21.8 (SD 3.54). The overall attrition rate was 10%. The following factors were associated with attrition from BCT: ethnicity (P < 0.01), BMI (P < 0.01), pre-enlisting motivation score (P < 0.01) and the number of mental health officer visits (P < 0.01). Using a decision-tree model, we found a high attrition rate among soldiers who had >5.2 to primary care physician visits (11% attrition rate versus 3%) or more than 11 sick leave days (59% versus 19%). CONCLUSIONS: This study sheds light on unique measures relating to attrition. Attrition is associated with several demographic and psychosocial factors. Early prediction of motivation and monitoring of healthcare utilization may enable early identification and focused interventions targeting soldiers at high risk for attrition. These findings need to be further translated into actionable directives and further investigations.

Modeling long-term effects attributed to nitrogen dioxide (NO2) and sulfur dioxide (SO2) exposure on asthma morbidity in a nationwide cohort in Israel.

Studies have provided extensive documentation that acutely elevated environmental exposures contribute to chronic health problems. However, only attention has been paid to the effects of modificate of exposure assessment methods in environmental health investigations, leading to uncertainty and gaps in our understanding of exposure- and dose-response relationships. The goal of the present study was to evaluate whether average or peak concentration exerts a greater influence on asthma outcome, and which of the exposure models may better explain various physiological responses generated by nitrogen dioxide (NO2) or sulfur dioxide (SO2) air pollutants. The effects of annual NO2 and SO2 exposures on asthma prevalence were determined in 137,040 17-year-old males in Israel, who underwent standard health examinations before induction to military service during 1999-2008. Three alternative models of cumulative exposure were used: arithmetic mean level (AM), average peak concentration (APC), and total number of air pollution exposure episodes (NEP). Air pollution data for NO2 and SO2 levels were linked to the residence of each subject and asthma prevalence was predicted using bivariate logistic regression. There was significant increased risk for asthma occurrence attributed to NO2 exposure in all models with the highest correlations demonstrated using the APC model. Data suggested that exposure-response is better correlated with NO2 peak concentration than with average exposure concentration in subjects with asthma. For SO2, there was a weaker but still significant exposure response association in all models. These differences may be related to differences in physiological responses including effects on different regions of the airways following exposure to these pollutants. NO2, which is poorly soluble in water, penetrates deep into the bronchial tree, producing asthmatic manifestations such as inflammation and increased mucus production as a result of high gaseous concentrations in the lung parenchyma. In contrast, SO2, which is highly water soluble, exerts its effects rapidly in the upper airways, leading to similar limited correlations at all levels of exposure with fewer asthmatic manifestations observed. These data indicate that differing exposure assessment methods may be needed to capture specific disease consequences associated with these air pollutants.

Sex differences in the association between body mass index and hypertension - a cross-sectional study in 717 812 adolescents.

In order to examine sex-specific differences in the association of body mass index (BMI) and hypertension, we conducted a retrospective, cross-sectional study of 717 812 (402 914 men and 314 898 women) Israeli Jewish adolescents aged 16.0-19.99 years medically screened for military service. A diagnosis of hypertension was established per history or if a mean of 10 separate blood pressure measurements exceeded 140/90, following an initial measurement higher than 140/90. Weight and height were measured. Prevalence of hypertension was 0.42% in men and 0.05% in women. In men, BMI was significantly associated with hypertension from the third decile (odds ratio [OR] 1.67, 1.06-2.65) up to the 10th decile (OR 30.17, 20.83-43.69). In women, we observed a significantly increased risk for hypertension in the ninth decile (OR 3.82, 1.42-10.22) and in the 10th decile (OR 18.92, 7.7-46.51), with no visible trend in lower deciles. BMI effects on hypertension prevalence are different in male and female adolescents.

Varicocoele among 1 300 000 Israeli adolescent males: time trends and association with body mass index.

Scarce data are available on epidemiology of varicocoele, the most common surgically correctable cause of male infertility. The objectives of this study were to evaluate the association between body mass index (BMI) and varicocoele and to assess trends in prevalence over time. We conducted a nationwide population-based long-term (1967-2010) study among 1 323 061 Israeli adolescent males using data from mandatory medical examination. BMI was grouped into underweight, normal weight, overweight and obese categories by percentiles adjusted for age in months and by further classification to five categories within normal weight. Univariable and multivariable logistic regression models were constructed, adjusting for possible confounders. Varicocoele prevalence (N = 47 398) increased during the study period from 1.6% for the 1950-1954 birth cohort to 4.6% for the 1990-1993 birth cohort, with the steepest rise in the normal weight group. Varicocoele unadjusted rates were highest (4.1%) among underweight and lowest (1.6%) among obese. In a multivariable model, adjusted for birth cohort, height, age and socio-demographic factors, we found a decreased risk for varicocoele in the overweight group [odds ratio (OR) = 0.51, 95% confidence interval (CI): 0.49, 0.54] and the obese group (OR = 0.34, 95% CI: 0.32, 0.37), compared with the normal weight group. Within the normal weight group, a monotonic inverse association between BMI percentile and varicocoele was observed, most notable among 75-84.9 percentile compared to 25-49.9 percentile (OR = 0.65, 95% CI: 0.63, 0.68). In conclusion, varicocoele is common among adolescents in Israel, and its prevalence had increased in recent decades, providing clues to direct further andrological research on the role of modern lifestyle and environment in the aetiology of varicocoele. BMI, across percentiles, was found to be monotonically inversely associated with varicocoele, thus directing research and clinical efforts.

Distinct long-term neurocognitive outcomes after equipotent sevoflurane or isoflurane anaesthesia in immature rats.

BACKGROUND: Many anaesthetics when given to young animals cause cell death and learning deficits that persist until much later in life. Recent attempts to compare the relative safety or toxicity between different agents have not adequately controlled for the relative dose of anaesthetic given, thereby making direct comparisons difficult. METHODS: Isoflurane or sevoflurane were given at 1 minimum alveolar concentration (MAC) for 4 h to postnatal day 7 (P7) rat pups. Beginning at P75 these animals underwent fear conditioning and at P83 Morris water maze testing to assess working memory, short-term memory and early long-term memory using delays of 1 min, 1 h, and 4 h. RESULTS: No difference between groups was seen in fear conditioning experiments. Morris water maze learning was equivalent between groups, and no difference was seen in working memory. Sevoflurane-treated animals had a deficit in early long-term memory, and isoflurane-treated animals had a deficit in both short-term and early long-term memory. CONCLUSIONS: Both isoflurane and sevoflurane delivered at 1 MAC for 4 h to immature rats caused a deficit in long-term memory. Isoflurane also caused a deficit in short-term memory. Isoflurane might be more detrimental than sevoflurane in very young animals.

Population-based trends in overweight and obesity: a comparative study of 2,148,342 Israeli male and female adolescents born 1950-1993.

BACKGROUND: The epidemic of obesity has been identified as a major source of morbidity, not just in developed countries but globally, in adults as well as at younger ages. OBJECTIVE: The aims of this study were to describe trends in obesity and overweight in Israeli adolescents and observe temporal changes and association by risk factors. METHODS: The research analyzed records of 2,148,342 Jewish adolescents, over a span of 44 years and included data for individual body measurements, place of residence, area of origin and education levels. Body mass index (BMI) was measured by professionals, calculated and categorized as overweight or obesity according to age- and gender-specific BMI curves established in recent years. We processed the data in multinomial logistic regression model and calculated odds ratios for various risk factors. RESULTS: Obesity and overweight are on the rise for male and female adolescents born from the mid-1960s onwards, and especially for men from the 1980s onwards. Risk factors for male adolescents include lower socioeconomic status, inferior education levels and Western origins (vs. Asian, African or Israeli origins). Risk modifiers for women were similar, except for African origins, which were associated with increased risk rather than decreased risk. Asian and Israeli origins were protective for both genders, and education was more strongly associated with obesity for women. CONCLUSIONS: We recommend stronger preventive efforts directed at adolescents as a whole, and particularly vulnerable groups with lower education levels and poverty, or those with specific geographical origins. Gender disparities are evident and should be considered in these efforts and in further research.

Reduced glucose effectiveness associated with reduced insulin release: an artifact of the minimal-model method.

We previously demonstrated that minimal model-derived estimates of glucose effectiveness (SG), based on the frequently sampled intravenous glucose tolerance test (SGFSIGT), were reduced in islet-transplanted or streptozotocin-treated dogs and in patients with insulin-dependent diabetes mellitus. To ascertain the validity of our observations, we compared SGFSIGT with estimates based on a basal hormone replacement glucose clamp (SGBRCLAMP) and a basal hormone replacement glucose tolerance test (SGBRGTT) in normal control (CNTL, n = 12) and streptozotocin-treated dogs with normal fasting plasma glucose (STZ-Rx, n = 9). SGFSIGT was reduced in STZ-Rx compared with CNTL (P < 0.05). However, neither SGBRCLAMP nor SGBRGTT was reduced in the STZ-Rx group (P > 0.05). Comparison of protocols for each subject indicated that SGFSIGT was greater than either SGBRCLAMP or SGBRGTT in control (P < 0.002) but not in STZ-Rx dogs (P > 0.1). The relationship of SGFSIGT to insulin secretory function suggests that our previous conclusion that SGFSIGT was reduced in subjects with limited insulin release may be an artifact of the minimal-model method. Our results suggest that caution must be exercised in the interpretation of differences in minimal-model estimates of SG between subject groups with significantly different levels of insulin secretory function.