Healthy Workers Research Articles

Association of WNT Gene Polymorphism with Frequency of Cytogenetic Disorders under the Action of Ionizing Radiation

The paper presents the results of a study of the association of single nucleotide polymorphisms of the WNT genes with an increased frequency of cytogenetic disorders in the blood lymphocytes of workers at an ionizing radiation facility exposed to long-term radiation exposure at doses of 100–500 mGy.The object of the study was the blood of 95 apparently healthy workers who were subjected to long-term technogenic external exposure to γ-radiation in doses from 100 to 500 mGy in the course of their professional activities. For all examined individuals, a standard cytogenetic analysis of blood lymphocytes was performed. Genomic DNA was isolated from workers’ blood lymphocytes using a “QIAamp DNA Blood mini Kit” (Qiagen, Germany). DNA was genotyped for 116 single nucleotide polymorphisms of the WNT genes using high-density “CytoScan™ HD Array” (Affymetrix, USA) chips (DNA chips). Taking into account the Bonferroni correction, an association of single nucleotide polymorphisms of the WNT genes with a high frequency of circular chromosomes in blood lymphocytes was established, all other types of cytogenetic disorders did not show statistical significance. As a result of the study, a single nucleotide polymorphism of the WNT9B gene rs1530364 was identified, which can be considered as a potential marker of individual radiosensitivity.

Bioelectric brain activity in workers with hand-arm vibration in dynamics

Introduction. A few neurophysiologic studies have shown that changes of the bioelectrical brain activity are observed in hand-arm vibration syndrome (HAVS) patients. There is practically no information about the state of bioelectrical brain activity in the hand-arm vibration. The purpose is to study the dynamics of the formation of neurophysiologic changes in workers exposed to hand-arm vibration. Materials and methods. Electroencephalography (EEG) and registration of evoked potentials (EP) was carried out in workers exposed to hand-arm vibration (practically healthy workers, HAVS individuals who continue to work in their occupation), twice in a connected sample. The results are presented as median, upper and lower quartiles, and extensive indicators. The significance of differences was assessed using Pearson’s χ2 test, Fisher’s angular transformation, and Wilcoxon T-test. Results. In dynamics, there is a change in the EEG pattern from disorganized with a predominance of alpha activity to disorganized with a predominance of delta, and theta activity; a decrease in the spectral power of the main EEG rhythms in all main functional leads in both examined groups. Diffuse changes in the EEG indicate a multisystem nature of bioelectrical brain activity disorders with involvement of the cerebral cortex, stem, and diencephalic structures of the brain. Changes in the amplitude-temporal parameters of EP manifested by an excess of the latency of the main peaks and a decrease in amplitude, indicate an imbalance in the central nervous system, general modulating influences on the cerebral cortex of the thalamocortical systems of the brain. Limitations. One occupational group with different levels of health status – practically healthy workers, HAVS individuals who continue to work in their occupation – was enrolled in the study. Conclusion. The one-direction and progressive development of changes in the bioelectrical brain activity has been established, manifested by a restructuring of the electrical activity of the brain, desynchronization of neuronal activity, an increase in the level of functional activity of the brain, and an imbalance of general modulating influences on the cerebral cortex. The identified changes are a manifestation of the nonspecific part of the pathogenesis of HAVS.

Evaluation of the early effects of the first-dose administration of the Sinovac vaccine on the retina, choroid, and optic disc using optical coherence tomography (OCT) and OCT-angiography

Aim To determine the effects of the first-dose administration of the Sinovac vaccine on the retina, choroid, and optic disc in healthy participants. Methods This prospective design study was conducted with 27 healthy healthcare workers who received the first dose of Sinovac vaccine and 25 healthy controls who were not vaccinated. In the vaccinated group, ophthalmological examinations and measurements were performed before vaccination and one week and one month after vaccination. Subfoveal, nasal, and temporal choroidal thicknesses (CTs), retinal nerve fiber layer (RNFL) thickness, and macular thickness (MT) were determined using spectral domain-optical coherence tomography at all visits. Superficial, deep, and peripapillary radial capillary plexus (superficial capillary plexus, deep capillary plexus (DCP), and radial peripapillary capillary, respectively), choriocapillaris vascular density, and foveal avascular zone parameters were measured on optical coherence tomography-angiography (OCT-A). Results No significant difference was detected between the two groups in terms of the parameters measured by OCT and OCT-A (p > 0.05 for all). The CT values measured in all quadrants were significantly higher at the first week after vaccination (p < 0.05 for all), and they returned to their pre-vaccination values at the first month post-vaccination measurement (p > 0.05 for all). Concerning the RNFL and MT values, there was no significant difference between the pre-vaccination and post-vaccination first-week measurements (p > 0.05 for all), but a statistically significant increase was detected in the post-vaccination first-month MT and RNFL measurements (p < 0.05 for all). Only the decreases in the foveal DCP and choriocapillaris vascular density values were significant at the first week after vaccination (p < 0.05 for all). Conclusion The early changes detected after vaccination in this study suggest the possibility that autoimmune, vascular, and inflammatory diseases may simultaneously emerge in the early post-vaccination period or may be triggered after vaccination, or that the vaccine may unmask these diseases.

Exploring exhaled breath volatile organic compounds in occupational asthma: a pilot cross-sectional study

Occupational asthma (OA) is divided into allergic asthma (AA) and irritant-induced asthma (IIA). IIA can be divided further into three different phenotypic subtypes. Volatile organic compounds (VOCs) in exhaled breath can reflect metabolic changes in the body, and a wide range of them have been associated with various diseases in the last two decades. This is the first known study to explore breath VOCs in subjects with OA, aimed to identify potential biomarkers to distinguish OA from healthy controls, as well as between different OA subgroups. In a cross-sectional investigation, exhaled breath from 40 patients with OA and 45 respiratory healthy healthcare workers were collected with ReCIVA® Breath Sampler. Samples were analyzed through an untargeted approach using thermal desorption-gas chromatography mass spectrometry (TD-GC-MS), and VOCs were identified according to tier classification. The data underwent analysis using both non-parametric and parametric statistical methods. 536 VOCs were identified. Significance (p<0.05) was observed in several emitted VOCs. Among these, compounds such as 1-hexadecanol, 2,3-butanediol, xylene, phenol, acetone, 3-methylhexane, methylcyclohexane, and isoprene have biological implications or are associated with exposures linked to OA. These VOCs may reflect metabolic changes in the body and the microbiome, as well as external exposures due to occupation.&#xD;In particular, 1-hexadecanol, 2,3-butanediol, xylene and phenol are associated with reduced nicotinamide adenine dinucleotide (NADH) and production of reactive oxygen species (ROS), mechanisms that can be linked to asthmatic diseases and therefore suggests its potential as biomarkers. This study demonstrates that VOCs detected in exhaled breath could serve as indicators of occupational exposure and enhance diagnostic accuracy for asthma.&#xD.

Influence of Night Shift Work on Heart Rate Variability in an Age- and Gender-Matched Study Group.

Regular and long-term shift work is associated with a number of chronic diseases. There is some evidence that shift work also has an influence on the autonomous nervous system. Studies that have examined the effect of shift work on heart rate variability (HRV) have not taken into account age and gender. Therefore, the aim of this study was to investigate the influence of night shift based on 24 h long-term analyses carried out on non-night shift days with a matched control group for age and gender. In total, 172 (128 male, 44 female) healthy shift night workers were compared with subjects from a non-night shift worker group at a ratio of 1:1, forming matched pairs based on the subjects' sex and age. HRV parameters were analyzed based on 24 h ECG recording. An analysis of the HRV parameters showed only a small difference but without statistical significance between the two groups with regard to all of the HRV parameters examined (SDNN, RMSSD, NN50, pNN50, VLF, LF, HF, LF/HF, DFA1, and DFA2). An analysis of the subgroup of subjects who had only worked night shifts for a minimum of 10 or 20 years, with the respective pairs matched by age and gender, did not reveal any significant differences between the HRV parameters of employees working night shifts and those not working night shifts. Taking into account qualitative aspects of HRV analysis, this study was thus able to show that working night shifts for many years may not have as big an influence on HRV as had been assumed so far.

Risk assessment of arsenic exposure to occupational disease artisanal and small-scale gold mining sites, Bombana Area, Southeast Sulawesi, Indonesia

Abstract Anthropogenic activities can lead to heavy metal accumulation in the body, causing heavy metal poisoning and occupational diseases. This study investigated the impact of Arsenic exposure on artisanal gold miners in Southeast Sulawesi, Indonesia. The study focused on miners at two Artisanal and Small-scale Gold Mining sites in Bombana area. The study sample comprises 63 individuals, with 54 individuals representing miners from the Rarowatu and North Rarowatu regions constituting the exposed group and 9 individuals representing non-miners from the Rumbia region forming the control group. Medical examinations and questionnaires were used to identify symptoms of occupational diseases. The As concentrations in human hair samples revealed that miners with over ten years of experience had significantly higher As concentrations (2.67 μg/g) than those exposed to less than ten years of durations (1.26 μg/g). The As concentration in the exposed group (1.61 μg/g) exceeds the World Health Organization guidelines (1 μg/g) and is higher than that of the control group (0.87 μg/g), although not statistically significant (p&lt;0.05). Additionally, there were no significant differences in As concentrations between sick and healthy workers with various symptoms (neurological, respiratory, musculoskeletal, degenerative, and others) (p-values: 0.08, 0.32, 0.69, 0.36, and 0.67, respectively). Long-term Artisanal and Small-scale Gold Mining miners had higher As exposure, but this study found no clear association between As concentrations and specific occupational diseases.

Impact of work pace on cardiorespiratory outcomes, perceived effort and carried load in industrial workers: a randomised cross-over trial

ObjectivesThis study investigates the impact of different work paces on cardiorespiratory outcomes, perceived effort and carried load (CL) in industrial workers.MethodsA randomised cross-over trial was conducted at a mid-sized steel...

Shift work and non-alcoholic fatty liver disease in young, healthy workers

Non-alcoholic fatty liver disease (NAFLD) is a relatively common disease, and preventing its occurrence is important for both individual health and reducing social costs. Shift work is reported to have several negative effects on health. An association has been observed between NAFLD and both sleep time and quality; however, this association remains unclear in night shift workers. We aimed to evaluate the relationship between shift work and the incidence of NAFLD. Overall, 45,149 Korean workers without NAFLD were included at baseline. NAFLD was defined as the presence of a fatty liver observed on ultrasonography without excessive alcohol use. incidence rate ratios for incident NAFLD were estimated using negative binomial regression according to age groups (20s, 30s, 40s, and 50s). In the 20s age group, shift work showed a significant incidence rate ratio (IRR) for NAFLD in all models. After adjusting for all variables, the IRR (95% confidence interval) was 1.24 (1.08–1.43) in the 20s age group. In their 20s, a significant association between shift work and incident NAFLD was consistently observed among women and workers with poor sleep quality. In this large-scale cohort study, shift work was significantly associated with the development of NAFLD among young workers in their 20s.

C-Mannosyl tryptophan is a novel biomarker for thrombocytosis of myeloproliferative neoplasms

C-Mannosyl tryptophan (CMW), a unique glycosylated amino acid, is considered to be produced by degradation of C-mannosylated proteins in living organism. Although protein C-mannosylation is involved in the folding and secretion of substrate proteins, the pathophysiological function in the hematological system is still unclear. This study aimed to assess CMW in the human hematological disorders. The serum CMW levels of 94 healthy Japanese workers were quantified using hydrophilic interaction liquid chromatography. Platelet count was positively correlated with serum CMW levels. The clinical significance of CMW in thrombocytosis of myeloproliferative neoplasms (T-MPN) including essential thrombocythemia (ET) were investigated. The serum CMW levels of the 34 patients with T-MPN who presented with thrombocytosis were significantly higher than those of the 52 patients with control who had other hematological disorders. In patients with T-MPN, serum CMW levels were inversely correlated with anemia, which was related to myelofibrosis (MF). Bone marrow biopsy samples were obtained from 18 patients with ET, and serum CMW levels were simultaneously measured. Twelve patients with bone marrow fibrosis had significantly higher CMW levels than 6 patients without bone marrow fibrosis. Collectively, these results suggested that CMW could be a novel biomarker to predict MF progression in T-MPN.

The microbiome of Total Suspended Particles (TSP) and its influence on the respiratory microbiome of healthy office workers.

Air particulate matter (PM) is widely recognized for its potential to negatively affect human health, including changes in the upper respiratory microbiome. However, research on PM-associated microbiota remains limited and mostly focused on PM (e.g., PM2.5 and PM10). This study aims to characterize for the first time the microbiome of Total Suspended Particles (TSP) and investigate the correlations of indoor TSP with the human upper respiratory microbiome. Biological and environmental samples were collected over three collection periods lasting three weeks each, between May and July 2022 at the University of Milan and the University of Insubria Como. TSP were sampled using a filter-based technique, while respiratory samples from both anterior nares (AN) and the nasopharynx (NP) were collected using swabs. Microbiome analysis of both human (N = 145) and TSP (N = 51) samples was conducted on metagenomic sequencing data. A comparison of indoor and outdoor TSP microbiomes revealed differences in microbial diversity and taxonomic composition. The indoor samples had higher relative abundance of environmental bacteria often associated with opportunistic infections like Paracoccus sp., as well as respiratory bacteria such as Staphylococcus aureus and Klebsiella pneumoniae. Additionally, both indoor and outdoor TSP samples contained broad spectrum antibiotic resistance genes. Indoor TSP exposure was negatively associated with commensal bacteria and positively associated with Staphylococcus aureus relative abundance. Finally, a correlation between the relative abundance of respiratory bacteria identified in the indoor TSP and the upper respiratory microbiome was found, suggesting a potential interaction between TSP and the upper airways.

Computational Analyses Reveal Deregulated Clock Genes Associated with Breast Cancer Development in Night Shift Workers.

Breast cancer (BC) is the leading cause of cancer death among women worldwide. Women employed in shift jobs face heightened BC risk due to prolonged exposure to night shift work (NSW), classified as potentially carcinogenic by the International Agency for Research on Cancer (IARC). This risk is linked to disruptions in circadian rhythms governed by clock genes at the cellular level. However, the molecular mechanisms are unclear. This study aimed to assess clock genes as potential BC biomarkers among women exposed to long-term NSW. Clock gene expression was analysed in paired BC and normal breast tissues within Nurses' Health Studies I and II GEO datasets. Validation was performed on additional gene expression datasets from healthy night shift workers and women with varying BC susceptibility, as well as single-cell sequencing datasets. Post-transcriptional regulators of clock genes were identified through miRNA analyses. Significant alterations in clock gene expression in BC compared to normal tissues were found. BHLHE40, CIART, CLOCK, PDPK1, and TIMELESS were over-expressed, while HLF, NFIL3, NPAS3, PER1, PER3, SIM1, and TEF were under-expressed. The downregulation of PER1 and TEF and upregulation of CLOCK correlated with increased BC risk in healthy women. Also, twenty-six miRNAs, including miR-10a, miR-21, miR-107, and miR-34, were identified as potential post-transcriptional regulators influenced by NSW. In conclusion, a panel of clock genes and circadian miRNAs are suggested as BC susceptibility biomarkers among night shift workers, supporting implications for risk stratification and early detection strategies.

Effects of pesticide exposure on the expression of selected genes in normal and cancer samples: Identification of predictive biomarkers for risk assessment

Pesticides pivotal in controlling pests, can represent a threat for human health. Regulatory agencies constantly monitor their harmful effects, regulating their use. Several studies support a positive association between long-term exposure to pesticides and chronic pathologies, such as cancer. Geno-toxicological biomonitoring has proven to be valuable to assess genetic risks associated with exposure to pesticides, representing a promising tool to improve preventive measures and identify workers at higher risk. In this study, a differential gene expression analysis of 70 candidate genes deregulated upon pesticide exposure, was performed in 10 GEO human gene expression DataSets. It was found that six genes (PMAIP1, GCLM, CD36, SQSTM1, ABCC3, NR4A2) had significant AUC predictive values. Also, CD36 was upregulated in non-transformed cell samples and healthy workers, but downregulated in cancer cells. Further validation in larger groups of workers will corroborate the importance of the identified candidates as biomarkers of exposure/effect.

Impact of environmental pollution on ant (Camponotus japonicus) development and labial gland disease

Metallic pollutants can have harmful impacts on ant morphology and physiology. We studied the occurrence of labial gland disease in Camponotus japonicus from two polluted areas (traffic pollution and industrial pollution) and one non-polluted area. We further analyzed the metal levels (Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn) and morphological characteristics (head width, body mass, and other morphological traits) of both diseased and healthy workers. Our results showed that labial gland disease was only present in polluted areas, indicating that pollution stress makes ants more vulnerable to infections. Our research revealed that diseased ants in polluted areas accumulate higher levels of metals in their bodies and have lower dry weight and residual body mass compared to healthy ants in non-polluted environments, negatively impacting their development. We evaluated the importance of these elements and found that Cu has the greatest impact on the health risk of C. japonicus. Our study underscores the significant impact of environmental pollution on ant morphology and physiology and raises concerns about the broader ecological implications.

A Descriptive Study of Pulmonary Function Comparison Between Spot Welding and Assembly Line Workers in a Large Automotive Factory in Iran

Background: This study seeks to define the pulmonary function of a considerably large group in one of the largest automotive companies in Iran. The aim of this study was to compare the two groups of spot-welding (exposed) and assembly line (unexposed) workers in terms of pulmonary function and conclude the probable impacts of metal fumes on pulmonary function in the two groups. Methods: A total of 1,798 spot-welding personnel and 2,160 assembly line personnel were compared in terms of pulmonary function. Moreover, 120 breathing zone samples were collected from the welders’ metal fumes and were analyzed. The parameters of age, anthropometric indices, smoking, and pulmonary symptoms were also compared with across the two groups. Results: Results revealed the FEV1 mean of the total population to be 3.9 ± 0.5 liters and FVC to have been 4.9 ± 0.7 liters. Besides, predicted FEV1 and FVC percentages across the whole population were close to 100%, suggesting the better condition of the studied population compared with normal individuals in the society. All the parameters of age, weight, height, and smoking status were similar in the two groups, and no statistically significant difference was observed between the two groups in terms of pulmonary functions. Conclusion: Implementation of professional health and health improvement programs, running screening programs, and hiring personnel with no history of mild pulmonary disorders, and healthy workers effect at the recruitment stage could be the reasons behind the lack of significant difference between the two exposed and unexposed groups to metal fumes in the automotive industry in terms of pulmonary function.

Assessment of Hand Grip Strength and Pinch Grip Strength among Healthy Embroidery Workers: Cross-Sectional Study

Background: Embroidery is a craft that decorates fabric or other materials by using a needle to apply thread or yarn. Hand and finger strength is essential during embroidery design to minimize discomfort and risk of upper extremity injuries Aims and objective: This study aims to assess hand grip strength and pinch grip strength among healthy embroidery workers. Methodology: 100 embroidery workers were recruited. Demographic details including BMI were taken in self-designed form. Hand grip strength was assessed by Jamar Hand Held Dynamometer. Pinch grip strength was assessed by a Pinch Guage Dynamometer. Statistical analysis was done using the Python software. Results: The study included 100 subjects that involved all female subjects aged 20 to 40 yrs. with 4 or more than 4 years of experience. The study showed that the hand grip strength of embroidery workers was more affected than the pinch grip strength. This study also showed that age is not related to the hand grip and pinch grip strength. It also showed that an increase in the years of experience increases hand grip and pinch grip strength (p&lt; 0.05) as well as grip strength was more in the dominant hand(p&lt;0.0001). Conclusion: Hand grip strength was found to be affected more than the pinch grip strength. They found no correlation with the age and there was a correlation with years of experience. KEYWORDS: Jamar Hand Held Dynamometer, Pinch Guage Dynamometer, strength, Age, skill workers.

Factors Influencing Community Resource Mobilization to Support Households in Achieving Sustainable Poverty Alleviation: The Case of Dao People in Thanh Hoa Province, Vietnam

This article explains the factors influencing community resource mobilization in achieving sustainable poverty alleviation focusing on Dao households in Vietnam. It found that two factors influenced community resource mobilization to help Dao households sustainably escape poverty focuses on two dimensions: internal and external factors. Internal factors include education level, occupation, skills, experience, the number of healthy workers in the household, and the household's physical capital resources. External factors encompass broader influences such as state policies and support from state organizations and non-governmental organizations. While internal factors are crucial in determining the ability to mobilize community resources, external factors, though not decisive, play a significant role in facilitating the mobilization of these resources to support the Dao people in Thanh Hoa in achieving sustainable poverty alleviation. This study contributes to the study on how poverty should be alleviated in communal levels in Asia with a special reference to Vietnam.

Postural shifts and body perceived discomfort during 1-hour sitting when leaning and sitting on an air-filled seat cushion among healthy office workers

This study compared the number of postural shifts and perceived discomfort while leaning and sitting on an air-filled seat cushion for 1 hour. Sixty office workers typed a standard text while leaning on a cushion placed behind the low back, sitting on a cushion placed under the buttocks, and sitting without a cushion (a control condition). The number of postural shifts was collected using a seat pressure mat device. Low back discomfort was assessed using the Borg CR-10 scale. Leaning on a seat cushion (22 shifts/h) led to a significantly higher number of postural shifts than sitting on a seat cushion (18 shifts/h) and the control condition (20 shifts/h). Leaning or sitting on a seat cushion significantly decreased low back discomfort compared to the control condition (p < 0.05). Leaning on a seat cushion placed behind the low back may be an effective means of preventing low back pain among office workers.

Sick leaves among healthy pregnant Croatian healthcare workers during the COVID-19 pandemic due to loopholes in the occupational safety system.

The aim of this study was to explore occupational safety in pregnant Croatian healthcare workers (HCWs) during the coronavirus disease 2019 (COVID-19) pandemic. To this end we composed an anonymous questionnaire that included pregnancy data, risk assessment and mitigation, and workplace intervention and distributed it to HCWs through social media of their groups and associations. The study includes a total of 173 respondents (71.1 % physicians, 19.7 % nurses, 9.2 % other HCWs) diagnosed with pregnancy in 2020 and 2021. Employers were notified about HCWs' pregnancy at the eighth (IQR 7.0-11.0) week of pregnancy, which delayed workplace risk assessment and mitigation beyond the first trimester. Only 19.6 % of the participants had the risk assessed and mitigated, mostly on their own initiative (76.5 %). After notifying employers about pregnancy, 37.0 % of participants opted for temporary work incapacity (TWI) due to "pregnancy complications" despite healthy pregnancy, 16.8 % were granted a pregnant worker's paid leave at the expense of the employer, while 5.8 % continued to work at the same workplace. Nurses used the TWI benefit more frequently than physicians (58.8 % vs 30.1 %, P=0.004). Our findings suggest that occupational safety of pregnant HCWs in Croatia lacks clear-cut and transparent strategies to protect pregnant HCWs, forcing them to misuse the healthcare system.

Stemming the tide: linking AI technology with workers retention

PurposeThe objective of this research is to examine the association of artificial intelligence (AI) awareness on workers' retention and the boundary conditions in the context of project organizations.Design/methodology/approachWe collected time-lagged data from project organizations in China.FindingsThe results showed that AI awareness predicted workers' turnover intention. Moreover, this association was moderated via supervisor support.Practical implicationsThis research provides several practical implications aimed at timely communication, training and automation guide for helping firms to foster healthy workplace climate, support and workers’ retention.Originality/valueThe rise of AI and its potential impact on manpower is a popular topic. Yet, the evidence of project workers’ awareness of such potential effects on their retention is scant. Therefore, this study broadens our understanding of the association of AI awareness on turnover intention and boundary conditions in the context of project organizations.

Assessing cardiovascular stress based on heart rate variability in female shift workers: a multiscale-multifractal analysis approach.

Sleep-wake cycle disruption caused by shift work may lead to cardiovascular stress, which is observed as an alteration in the behavior of heart rate variability (HRV). In particular, HRV exhibits complex patterns over different time scales that help to understand the regulatory mechanisms of the autonomic nervous system, and changes in the fractality of HRV may be associated with pathological conditions, including cardiovascular disease, diabetes, or even psychological stress. The main purpose of this study is to evaluate the multifractal-multiscale structure of HRV during sleep in healthy shift and non-shift workers to identify conditions of cardiovascular stress that may be associated with shift work. The whole-sleep HRV signal was analyzed from female participants: eleven healthy shift workers and seven non-shift workers. The HRV signal was decomposed into intrinsic mode functions (IMFs) using the empirical mode decomposition method, and then the IMFs were analyzed using the multiscale-multifractal detrended fluctuation analysis (MMF-DFA) method. The MMF-DFA was applied to estimate the self-similarity coefficients, α(q, τ), considering moment orders (q) between -5 and +5 and scales (τ) between 8 and 2,048 s. Additionally, to describe the multifractality at each τ in a simple way, a multifractal index, MFI(τ), was computed. Compared to non-shift workers, shift workers presented an increase in the scaling exponent, α(q, τ), at short scales (τ < 64 s) with q < 0 in the high-frequency component (IMF1, 0.15-0.4 Hz) and low-frequency components (IMF2-IMF3, 0.04-0.15 Hz), and with q> 0 in the very low frequencies (IMF4, < 0.04 Hz). In addition, at large scales (τ> 1,024 s), a decrease in α(q, τ) was observed in IMF3, suggesting an alteration in the multifractal dynamic. MFI(τ) showed an increase at small scales and a decrease at large scales in IMFs of shift workers. This study helps to recognize the multifractality of HRV during sleep, beyond simply looking at indices based on means and variances. This analysis helps to identify that shift workers show alterations in fractal properties, mainly on short scales. These findings suggest a disturbance in the autonomic nervous system induced by the cardiovascular stress of shift work.