Occupational exposure to fine particulate matter in the reinforced concrete production and its association with respiratory symptoms and lung function.

BACKGROUND: Reinforced concrete production is widespread, but little is known about the occupational exposure to fine particulate matter (PM) in such workplaces, including from metalworking and concrete processing. Therefore, the aim was to characterize exposure to fine PM in the typical workplaces of the whole production cycle and to quantify the risk of respiratory symptoms and lung function in a cohort of reinforced concrete parts production industry. METHODS: At a reinforced concrete parts producing facility in Almaty, we collected 50 personal PM2.5 samples from the main exposure sites and the measured mass concentrations using gravimetric method. Workers also completed questionnaires on a detailed working history, respiratory symptoms (chronic obstructive pulmonary disease (COPD) Assessment Tool (CAT)), followed by spirometry. The association of cumulative dose with CAT score and forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) was tested with multiple regression. RESULTS: The highest PM2.5 concentrations were found in the concrete-mixing unit (median 1180 µg/m3), followed by metalworking (510 µg/m3), armature workshop (375 µg/m3) and molding site (245 µg/m3), different from the concentrations in the office (29.5 µg/m3), Kruskall-Wallis p < 0.001. Cumulative PM2.5 dose, mg/m3-year (beta 0.10 (95% confidence interval (CI) 0.05; 0.15)) was strongly associated with CAT score, whereas production with FEV1/FVC (beta -4.96 (-8.31; -1.61)), independent of smoking and chronic bronchitis and sex. CONCLUSIONS: Mixing concrete and metalworks pose the greatest risk for worker's health in the reinforced concrete production from the inhalational exposure to aerosol, adversely affecting respiratory health.

Asthma control in Kazakhstan: need for urgent action.

BACKGROUND: Asthma control, patients' awareness level and adherence to treatment in Kazakhstan have never been studied. The aim of this study was to verify the prevalence of controlled, poorly controlled and uncontrolled asthma in a large sample of three largest cities of Kazakhstan. METHODS: We recruited 600 (median age 54 (interquartile range (IQR) 22) years, 64% females) patients with diagnosis confirmed earlier in the outpatient facilities in Almaty, Astana and Shymkent in 2020-2021. We offered a structured questionnaire on asthma control and risk factors as of GINA and performed spirometry. We report the prevalence of asthma control, knowledge and skills and pharmacological treatment with 95% confidence interval (CI) and the association of selected predictors with asthma control. RESULTS: With the median of 9 (IQR 13) years of diagnosis, 40% of patients had comorbid COPD and 42% had allergic rhinitis, whereas 32% lived with pets. Asthma was well-controlled in only 12.3% (95% CI 9.7-15.0), partly controlled in 29.8% (95% CI 26.2-33.5) and uncontrolled in 57.8% (95% CI 53.9-61.8) patients. ACQ-5 score (range 0-5.8, median 2) equaled 0.2 (IQR 0.85) in well-controlled asthma patients, 1.4 (IQR 1) in partly controlled and 2.8 (IQR 1.4) in uncontrolled asthma patients. Knowledge and skills levels were very low. Only 54% were on inhaled corticosteroids (52.2% of them used budesonide/formoterol and 39.5% used fluticasone/salmeterol). 39% used steroids per os or parenterally within a period of 12 months (51% of patients with uncontrolled asthma). CONCLUSION: Asthma control, knowledge and skills levels of asthma patients in the largest cities of Kazakhstan remain unacceptably low, whereas pharmacological treatment is far from optimal. Urgent action should be taken to support doctors' training, and we call to launch a national asthma program to coordinate asthma care in Kazakhstan.

Fractional exhaled NO in a metalworking occupational cohort.

PURPOSE: Secondary metalworking carries exposure to relatively heavy levels of respirable particulate. We investigated the extent to which metalworking is associated with increased exhaled nitric oxide (FeNO), an established inflammatory biomarker. METHODS: We studied 80 metalworking factory employees in Kazakhstan. Informed by industrial hygiene data, we categorized them into three groups: (1) machine operators (41%); (2) welders or assemblers (33%); and (3) all others, including administrative and ancillary staff (26%). Participants completed questionnaires covering occupational history, smoking, home particulate sources, respiratory symptoms, and comorbidities. We measured exhaled carbon monoxide (CO), exhaled fractional nitric oxide (FeNO), and spirometric function. We used mixed-effects modeling to test the associations of occupational group with FeNO, adjusted for covariates. RESULTS: The median age was 51.5 (interquartile range 20.5) years; 7% were women. Occupational group (p < 0.01), daily current cigarette smoking intensity (p < 0.05), and age (p < 0.05), each was statistically associated with FeNO. Welders, or assemblers (Group 2), who had intermediate particulate exposure, manifested significantly higher exhaled FeNO compared to machinists (Group 1, with the highest particulate exposure) and all others (Groups 3, the lowest particulate): adjusted Group 2 mean 44.8 ppb (95% confidence interval (CI) 33.8-55.9) vs. Group 1 24.6 ppb (95% 20.5-28.7) and Group 3, 24.3 ppb (95% CI 17.7-30.9). Secondhand smoking and height were not associated with FeNO. CONCLUSION: In a metalworking industrial cohort, welders/assemblers manifested significantly higher levels of FeNO. This may reflect respiratory tract inflammation associated with airborne exposures specific to this group.

Health-related quality of life in a general population sample in Kazakhstan and its sociodemographic and occupational determinants.

BACKGROUND: Health-related quality of life (HRQL) in the general population of Kazakhstan has never been characterized. We constructed this population-based study of the largest city in Kazakhstan, Almaty with the aim to quantitatively assess HRQL and ascertain whether occupation and lifestyle are associated with HRQL in this population. METHODS: In a random sample (N = 1500) of general population in Almaty (median age 49 (interquartile range 28) years, 50% women), we collected data on demographics, socioeconomic status, lifestyle, lifetime occupational history and general HRQL using SF-8 instrument. The association of demographic and occupational predictors with HRQL was tested in multiple regression models. RESULTS: No occupational associations were found for physical component score in the models adjusted for age, sex, income, cigarette and waterpipe smoking, electronic cigarette use, physical activity, alcohol and exposure to secondhand smoke. Ever being a manager (ß - 1.63 (95% confidence interval (CI) - 2.92; - 0.34)), a welder (ß - 5.11 (95% CI - 8.77; - 1.46)) and a secretary (ß - 5.06 (95% CI - 8.56; - 1.56)) for one year or more was associated with poorer mental component score in the models adjusted for age, sex, income, cigarette smoking, physical activity and each other. Age, income and physical activity were independent predictors of both physical and mental components. CONCLUSIONS: Occupational history is associated with HRQL in the general population in Almaty, Kazakhstan, but the mechanism explaining this association should be further elucidated.

Testosterone and occupational burnout in professional male firefighters.

BACKGROUND: Very little is known about the biologic predictors of the occupational burnout in firefighters. The aim of this study was to characterize testosterone profile of active firefighters and quantify its association with three domains of the occupational burnout. METHODS: We enrolled 100 firefighters (median age 28 (interquartile range (IQR) 9.8) years with 5 (IQR 9) years in service) of three fire departments in Almaty, Kazakhstan. Demographics, smoking status, health-related quality of life (HRQL) and burnout scores of Maslach Burnout Inventory were assessed using a questionnaire, while total blood testosterone was measured in venous blood. Logistic regression models were used to quantify the association of blood testosterone with each burnout domain in the adjusted for confounders models. RESULTS: The median blood testosterone level was 14 (IQR 3.5) nmol/l and was only predicted by age (beta - 0.14, p < 0.01, 79% power). There were no differences in blood testosterone levels between occupational groups (Group 1 (firefighters), 14.6 (IQR 3.4); Group 2 (fire truck drivers), 14.7 (IQR 5.6); Group 3 (shift commanders, division heads, department managers and engineers), 14 (IQR 4.1) nmol/l, Kruskal-Wallis p = 0.32) or departments. Testosterone could not predict EX or CY, but had a negative association with PE score reflecting more burnout (odds ratio 1.18 (95% confidence interval 1.01;1.38)), adjusted for age, mental component of HRQL and education. CONCLUSIONS: Firefighters with higher testosterone may develop burnout in PE earlier, and this should be considered for proper work placement within the rescue system.

Plasma cutting and exposure to PM2.5 metal aerosol in metalworking, Almaty, Kazakhstan, 2020.

OBJECTIVES: Little is known regarding the metal working subprocesses that determine exposures in the workplace primarily because their segregation from the main process is rather difficult in real-life occupational settings. The present study aimed to identify the subprocesses in a metalworks plant with high personal exposure to particulate matter (PM2.5) metal aerosol in order to plan future risk reduction interventions. METHODS: A total of eighty 8-hour PM2.5 metal aerosol samples from the breathing zone of four workers in each of four major operations (plasma cutting, machine operating, assembling and welding) were collected in a metalwork plant in Almaty in January to June 2020. Minimal, maximal, time-weighted average PM2.5 metal aerosol mass concentrations were recorded with TSI SidePak AM520 personal aerosol and analysed using analysis of variance (ANOVA) after normalisation. RESULTS: The overall sampling time was 640 hours. Maximal 1 min and geometric mean PM2.5 concentrations were 8.551 and 1.7268 mg/m3 in plasma cutting; 4.844 and 0.9343 mg/m3 in machine operating; 2.993 and 0.6898 mg/m3 in assembling; and 2.848 and 0.4903 mg/m3 in welding. Using a Tukey-Kramer test after a one-way ANOVA, plasma cutting concentrations were significantly higher compared with all other operations (F-ratio 29.6, p<0.001). The fold-range containing 95% of the total variability (R0.95) from all samples was 12.5. CONCLUSIONS: The highest PM2.5 concentrations were found in plasma cutting, potentially elevating the risk of systemic inflammatory effects.

The Occupational Burden of Nonmalignant Respiratory Diseases. An Official American Thoracic Society and European Respiratory Society Statement.

Rationale: Workplace inhalational hazards remain common worldwide, even though they are ameliorable. Previous American Thoracic Society documents have assessed the contribution of workplace exposures to asthma and chronic obstructive pulmonary disease on a population level, but not to other chronic respiratory diseases. The goal of this document is to report an in-depth literature review and data synthesis of the occupational contribution to the burden of the major nonmalignant respiratory diseases, including airway diseases; interstitial fibrosis; hypersensitivity pneumonitis; other noninfectious granulomatous lung diseases, including sarcoidosis; and selected respiratory infections. Methods: Relevant literature was identified for each respiratory condition. The occupational population attributable fraction (PAF) was estimated for those conditions for which there were sufficient population-based studies to allow pooled estimates. For the other conditions, the occupational burden of disease was estimated on the basis of attribution in case series, incidence rate ratios, or attributable fraction within an exposed group. Results: Workplace exposures contribute substantially to the burden of multiple chronic respiratory diseases, including asthma (PAF, 16%); chronic obstructive pulmonary disease (PAF, 14%); chronic bronchitis (PAF, 13%); idiopathic pulmonary fibrosis (PAF, 26%); hypersensitivity pneumonitis (occupational burden, 19%); other granulomatous diseases, including sarcoidosis (occupational burden, 30%); pulmonary alveolar proteinosis (occupational burden, 29%); tuberculosis (occupational burden, 2.3% in silica-exposed workers and 1% in healthcare workers); and community-acquired pneumonia in working-age adults (PAF, 10%). Conclusions: Workplace exposures contribute to the burden of disease across a range of nonmalignant lung conditions in adults (in addition to the 100% burden for the classic occupational pneumoconioses). This burden has important clinical, research, and policy implications. There is a pressing need to improve clinical recognition and public health awareness of the contribution of occupational factors across a range of nonmalignant respiratory diseases.

Smoking practices in relation to exhaled carbon monoxide in an occupational cohort.

BACKGROUND: Exposure to carbon monoxide (CO) remains a leading occupational hazard in firefighters, but cigarette and waterpipe smoking likely contributes to the other sources of CO in such workers. The aim of this study was to estimate the contribution of self-reported active cigarette smoking, waterpipe use, and potential job-related sources of CO to the level of exhaled CO in firefighters. METHODS: We surveyed the personnel of 18 fire stations (N = 842), median age 28 years, who participated at an annual screening not timed to coincide with recent firefighting. We surveyed smoking and waterpipe history, exposure to secondhand smoke (SHS), use of coal for health and biomass for cooking and time since last exposure to firefighting in the workplace. We measured exhaled CO with an instantaneous reading device (piCO Smokerlyzer). We used multivariable regression models to test the association of time since last smoked cigarette (≤12 h) and waterpipe (≤12 h) and time since last fire (≤6 h) with exhaled CO. RESULTS: In analysis limited to men (93.5% of all surveyed), 42% were daily cigarette; 1% were waterpipe smokers; 94% were exposed to SHS, 29% used coal for heating and 4% used biomass for cooking. The median CO was 4 (interquartile range 3;8) ppm. Age (beta 0.74 per 10 years, p < 0.001), use of biomass fuel for cooking (beta 1.38, p = 0.05), cigarette smoked in the last 12 h (beta 8.22, p < 0.001), waterpipe smoked in the last 12 h (beta 23.10, p < 0.001) were statistically associated with CO, but not time since last fire (≤6 h) (beta 4.12, p = 0.12). There was a significant interaction between older age and firefighting for exhaled CO (p = 0.03). CONCLUSIONS: Cigarette and recent waterpipe smoking are associated with increased exhaled CO in firefighters. Firefighting itself was a less potent contributor to exhaled CO when measured at an annual screening, but an age interaction was manifested.

ADIPOQ, KCNJ11 and TCF7L2 polymorphisms in type 2 diabetes in Kyrgyz population: A case-control study.

The aim of this study was to ascertain the polymorphic markers profile of ADIPOQ, KCNJ11 and TCF7L2 genes in Kyrgyz population and to analyze the association of polymorphic markers and combinations of ADIPOQ gene's G276T locus, KCNJ11 gene's Glu23Lys locus and TCF7L2 gene's VS3C>T locus with type two diabetes (T2D) in Kyrgyz population. In this case-control study, 114 T2D patients 109 non-diabetic participants were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Two individual polymorphisms (ADIPOQ rs1501299, KCNJ11 rs5219) were found to be associated with T2D. We found two (Lys23Lys/CC and Glu23Lys/CT) of the overall nine combinations, which were more prevalent in T2D group compared to controls (χ2 = 4.21, P = 0.04). Lys23Lys/CC combination was associated with a 2.65-fold increased likelihood of T2D (OR = 2.65, 95% CI 1.12-6.28), whereas the Glu23Lys/CT combination also increased such likelihood (OR = 3.88, 95% CI 1.27-11.91). This study demonstrated some association of 276T allele and ADIPOQ gene G276T heterozygous genotype as well as KCNJ11 gene 23Lys allele with T2D in ethnic Kyrgyz, but study results should be interpreted with caution because of the limited statistical power.

Age and work duration do not predict burnout in firefighters.

BACKGROUND: The aim of this study was to ascertain the prevalence of burnout in Kazakhstan firefighters with regard to position and to identify predictors of faster burnout in order to plan future preventive strategies. METHODS: Data on demographics, lifestyle, fatigue (Fatigue Severity Scale (FSS)), SF-8 health-related quality of life (HRQL) and Maslach Burnout Inventory (MBI) emotional exhaustion (EX), cynicism (CY) and professional efficacy (PE) were obtained from 604 (94% men, median age 27 (interquartile range (IQR) 12) years) firefighters from all 18 fire departments of the city of Almaty. Associations between predictors and burnout EX, CY and PE dimensions were tested using multivariate logistic regression analyses. RESULTS: Burnout scores were low in this sample, including EX (0.6; IQR 1.55), CY (1.2; IQR 1.8) and PE (4.8; IQR 2.4). The highest median EX score (1.5 (IQR 2.0)) was in managers as opposed to the lowest in drivers (0.4 (IQR 1.4)), (p < 0.01). The greatest CY difference was between managers (2.1 (IQR 2.2)) and trainees (0.4 (IQR 1.1)) (p < 0.001). Age, work duration, education or fatigue were not associated with EX or CY in adjusted models. Better HRQL predicted lower EX and CY burnout, whereas alcohol never-use and language barrier predicted high CY. Male sex and no university degree predicted high PE burnout. CONCLUSIONS: Firefighting managers are at risk for higher burnout, irrespective of age and work duration, and the targeted intervention to combat burnout should include better uniform, mitigation of language barrier, general health improvement and less alcohol.

Mutations of rpoB, katG, inhA and ahp genes in rifampicin and isoniazid-resistant Mycobacterium tuberculosis in Kyrgyz Republic.

BACKGROUND: The aim of this study was to identify mutations of rpoB, katG, inhA and ahp-genes associated Mycobacterium tuberculosis resistance to rifampicin (RIF) and isoniazid (INH) in Kyrgyz Republic. We studied 633 smear samples from the primary pulmonary tuberculosis (TB) patients. We verified Mycobacterium tuberculosis susceptibility to RIF and INH using culture method of absolute concentrations, and commercially available test named "TB-BIOCHIP" (Biochip-IMB, Moscow, Russian Federation). RESULTS: For RIF-resistance, TB-BIOCHIP's sensitivity and specificity were 88% and 97%, 84% and 95% for INH-resistance, and 90% and 97% for multi-drug resistance (MDR). In RIF-resistant strains, TB-BIOCHIP showed mutations in codons 531 (64.8%), 526 (17.3%), 516 (8.1%), 511 (5.4%), 533 (3.2%), 522 (0.6%) and 513 (0.6%) of rpoB gene. The most prevalent was Ser531 > Leu mutation (63.7%). 91.2% of mutations entailing resistance to INH were in katG gene, 7% in inhA gene, and 1.8% in ahpC gene. Ser315→Thr (88.6%) was the most prevalent mutation leading to resistance to INH. CONCLUSIONS: In Kyrgyz Republic, the most prevalent mutation in RIF-resistant strains was Ser531 → Leu in rpoB gene, as opposed to Ser315 → Thr in katG gene in INH-resistant Mycobacterium tuberculosis. In Kyrgyz Republic, the major reservoir of MDR Mycobacterium tuberculosis were strains with combined mutations Ser531 → Leu in rpoB gene and Ser315 → Thr in katG gene. TB-BIOCHIP has shown moderate sensitivity with the advantage of obtaining results in only two days.

The association of Val109Asp polymorphic marker of intelectin 1 gene with abdominal obesity in Kyrgyz population.

BACKGROUND: The aim of this study was to quantify the association of Val109Asp polymorphism of intelectin 1 (ITLN1) gene with the abdominal obesity (AO) in Kyrgyz population. METHODS: Patients admitted to annual screening at a local outpatient facility were enrolled or this study. We genotyped 297 nonrelated adults of Kyrgyz ethnicity, of whom 127 were AO patients, including 46 men and 81 women with the mean age 53.2 ± 7.1 years, and 170 non-obese controls, including 61 men and 109 women with the mean age 52.0 ± 9.0 years. AO was defined as having waist circumferences ≥ 102 cm in men and ≥ 88 cm in women. We used PCR-RFLP method to define Val109Asp polymorphism of ITLN1 gene. RESULTS: Asp109Asp, Asp109Val and Val109Val genotypes were found in 48%, 40%, and 12% of AO patients respectively, and in 53%, 43%, and 4% of controls, whereas Val109Val homozygous genotype of ITLN1 gene Val109Asp polymorphic marker was significantly more prevalent in AO patients. In Kyrgyz population, Val109Val genotype of ITLN1 gene increased the risk of AO (odds ratio (OR) 3.12, 95% CI 1.23-7.90). Asp109Asp homozygous genotype, on opposite, was not associated with this condition (OR 0.82, 95% CI 0.53-1.30). Finally, the allelic variants of Val109Asp polymorphism of ITLN1 gene were not associated with AO. CONCLUSION: Significant increase in the frequency of Val109Val genotype of ITLN1 gene in AO patients may be indicative of some potential role of ITLN1 gene in molding genetic predisposition to AO in the Kyrgyz. This requires further elaboration in the future studies.

The association of polymorphic markers Arg399Gln of XRCC1 gene, Arg72Pro of TP53 gene and T309G of MDM2 gene with breast cancer in Kyrgyz females.

BACKGROUND: The association of genes XRCC1, TP53 and MDM2 with breast cancer (BC) has never been tested in Kyrgyz population. We, therefore, aimed to identify an association of alleles and genotypes of polymorphic markers Arg399Gln of gene XRCC1, Arg72Pro of gene TP53, and T309G of gene MDM2 with the risk of BC in Kyrgyz women. METHODS: This was a case-control study of 219 women of Kyrgyz origin with morphologically verified BC (N = 117) and 102 controls, age-matched with BC cases. The mean age of subjects in this study was 52.2 ± 10.8 years. We extracted DNA from the venous blood and genotyped polymorphic markers Arg399Gln of gene XRCC1, Arg72Pro of gene TP53 and T309G of gene MDM2 using polymerase chain reaction and the method of restriction fragment polymorphism. RESULTS: Allele 399Gln (OR 1.57; 95% CI 1.05-2.35), Arg399Gln of gene XRCC1 heterozygous genotype (OR 2.77; 95% CI 1.60-4.80), the combination of Arg399Gln/Arg72Pro of genes XRCC1/TP53 heterozygous genotype (OR 3.98; 95% CI 1.57-10.09), Arg399Gln/T309G of genes XRCC1/MDM2 (OR 3.0; 95% CI 1.18-7.56), as well as Arg399Gln/Arg72Pro/T309G of genes XRCC1/TP53/MDM2 (OR 6.40; 95% CI 1.18-34.63) were associated with BC in Kyrgyz women. CONCLUSIONS: This is the first study to identify the inter-loci interaction and to find molecular markers of individual risk of BC in Kyrgyz women.

Fatigue and sleepiness determine respiratory quality of life among veterans evaluated for sleep apnea.

BACKGROUND: In those with symptoms indicative of obstructive sleep apnea (OSA), respiratory-specific health-related quality of life (HRQL) may be an important patient-centered outcome. The aim of this study was to assess the associations between sleepiness, fatigue, and impaired general and respiratory-specific HRQL among persons with suspected OSA. METHODS: We evaluated military veterans consecutively referred for suspected OSA with sleep studies yielding apnea-hypopnea index (AHI) values. They also completed the sleepiness (Epworth Sleepiness Scale [ESS]), and fatigue (Fatigue Severity Scale [FSS]) questionnaires, as well as two HRQL instruments (the generic Short-Form SF-12v2 yielding the Physical Component Scale [PCS] and the respiratory-specific Airways Questionnaire [AQ]-20R). Multiple linear regression tested the associations between ESS and FSS (standardized as Z scores for scaling comparability) with AQ-20R, accounting for AHI, SF-12v2-PCS and comorbid respiratory conditions other than OSA. RESULTS: We studied 1578 veterans (median age 61.1 [IQR 16.8] years; 93.9% males). Of these, 823 (52%) met AHI criteria for moderate to severe OSA (AHI ≥15/h). The majority reported excessive daytime sleepiness (53%; median ESS 11 [IQR 9]) or fatigue (61%; median FSS 42 [IQR 23]). The median AQ-20R was 4 [IQR 1-8]. Controlling for AHI, SF-12v2-PCS, respiratory co-morbid conditions, body mass index, and demographics, both ESS and FSS were significantly associated with poorer AQ-20R: for each; ESS, 1.6 points (95% CI 1.4-1.9), and for FSS, 2.5 points (95% CI, 2.3-2.7). CONCLUSIONS: Greater daytime sleepiness and fatigue are associated with poorer respiratory-specific HRQL, over and above the effects of OSA, respiratory comorbidity, and generic physical HRQL.

Tobacco use among Kyrgyzstan medical students: an 11-year follow-up cross-sectional study.

BACKGROUND: Medical students are the first line active force to combat tobacco epidemic, but they may suffer from high smoking prevalence and wrong attitude themselves. The aim of the study was to assess the effect of current curriculum on smoking behavior of medical students in Kyrgyzstan. METHODS: 20% random sample of all 6 years of the School of Medicine in Kyrgyz State Medical Academy were interviewed in spring 2016. The questionnaire included sections on tobacco products consumption and knowledge and attitude to counseling. We verified smoking status with exhaled CO measurement using Bedfont Smokelyzer. RESULTS: In 618 students (48% female), the overall daily cigarette smoking prevalence was 21% (34% in males and 6% in females), being highest in years 1 and 3 and least in year 5 (prevalence difference 14%). With very low smokeless products and electronic cigarettes use prevalence, ever-smoking prevalence of waterpipe use was very high, reaching 85% in 6-year male students with alarmingly high prevalence in female students also. Only 74% students responded there was 100% evidence of harmful effects of tobacco, unchanged throughout the course of study. CONCLUSIONS: The use of tobacco products, especially smoking waterpipe, in Kyrgyzstan medical students remains very high. Coupled with poor knowledge and high demand for more information, this demonstrates urgent need for more active and advanced training on tobacco control in medical school.

Occupation and chronic obstructive pulmonary disease in Minsk tractor plant workers.

BACKGROUND: The aim of this study was to measure the association of exposure to dust at workplace with COPD using objective methods of exposure and outcome classification. METHODS: Forced expiratory volume in one second (FEV1 ) to forced vital capacity (FVC) <70%; FVC below LLN, and FEV1 below LLN from the annual screening of Minsk Tractor Plant workers (N = 458) were tested for predictors in an adjusted logistic regression model. RESULTS: In a regression model, adjusted for pack-years of smoking, age, sex, and work duration, work in highly exposed workplaces was associated with FEV1 /FVC<70% (odds ratio (OR) 2.10 (95% confidence interval (CI) 1.16;3.83); and FEV1

Is Smoking a Predictor for Acute Mountain Sickness? Findings From a Meta-Analysis.

AIM: Studies of the potential association between cigarette smoking and acute mountain sickness (AMS) have reached contradictory conclusions. Our aim was to perform a meta-analysis of studies across a range of populations to ascertain better the true relationship between cigarette smoking and AMS. MATERIALS AND METHODS: We used the PRISMA protocol to identify and screen eligible studies of smoking and AMS. Databases including Pubmed and Google Scholar were searched, using the terms "smoking" and "acute mountain sickness." We conducted a meta-analysis of the selected studies in order to evaluate causal inference, evaluate potential biases, and investigate possible sources of heterogeneity across studies. RESULTS: We identified 3907 publications, of which 29 were eligible for inclusion by reporting smoking status and AMS. Of these, eight publications were excluded because they were duplicative or were lacking quantitative data. The 21 studies analyzed included 16 566 subjects. These fell into two groups: occupational/military (n = 8) or volunteers/trekkers/mixed (n = 13). Study heterogeneity was high (X (2) = 55.5, P < .001). Smoking was not statistically associated with increased risk of AMS: pooled OR = 0.88 (95% CI = 0.74-1.05). Stratification yielded similar risk estimates among the occupational/military studies versus all others and studies at relatively higher and lower altitudes. CONCLUSIONS: Overall, smoking was not statistically significantly associated with AMS: there is no consistent effect of cigarette smoking acting as either a protective factor against or a risk factor for AMS. IMPLICATIONS: This is the first quantitative assessment of published studies on smoking and AMS, which shows smoking to be neither a risk, nor protective. Studies specifically focusing on smoking as a risk factor, should guide further research on this issue. Although all smokers should be strongly advised to quit, studies on risk factors for AMS focusing on other exposures could shed light on the full range of risks for AMS.

Smoking increases the risk of acute mountain sickness.

OBJECTIVE: We aimed to ascertain risk factors for acute mountain sickness (AMS) in miners exposed to chronic intermittent high altitude conditions. METHODS: All new hires (2009-2012) for mine employment (4000 m above sea level) were followed up for 12 months after first ascent. Demographics, physiologic data, and cigarette smoking were assessed at preemployment screening. Mine site clinic care for AMS defined incident events. Cox regression analysis estimated risk of AMS associated with smoking and selected covariates. RESULTS: There were 46 AMS cases among 569 individuals during the first 12 months of employment. Adjusted for age, sex, and altitude of permanent residence, cigarettes smoked per day before hiring were prospectively associated with AMS (hazard ratio [HR], 1.9; 95% CI, 1.1 to 3.2 per 10 cigarettes smoked). This risk was higher in the subset of workers with less demanding physical work (n=336; HR, 3.3; 95% CI, 1.7 to 6.3), whereas among those with more physically demanding jobs (n=233), smoking was not associated with increased risk (HR, 0.6; 95% CI, 0.1 to 2.3). CONCLUSIONS: In workers newly hired to work at high altitude, smoking increases the likelihood of AMS, but this effect appears to be operative only among those with less physically demanding work duties.

Work at high altitude and non-fatal cardiovascular disease associated with unfitness to work: Prospective cohort observation.

INTRODUCTION: Mining at high altitude exposes workers to hypoxic environment and cold climate in addition to conventional hazards in mining, but very little is known on how to define fitness to work in prospective candidates with pre-existing conditions. The aim of the current study was to define the incidence of cardiovascular diseases leading to unfitness to work as well as their predictors in a prospective observation. METHODS: A total of 569 prospective employees (median age 34 (interquartile range (IQR) 28;40) years, 95% men 85% mid-altitude residents) for a high-altitude gold mine in Kyrgyzstan operating at 3800-4500 meters above sea level were screened at pre-employment in 2009-2012 and followed by January 2022. Cox regression was used to quantify the association of baseline demographics and physiological variables with newly diagnosed cardiovascular diseases (CVD) leading to unfitness to work, expressed as hazard ratios (HRs) with 95% confidence intervals (CI). RESULTS: With 5190 person-years of observation, 155 (27%) workers have left work, of whom 23 had a newly identified CVD leading to unfitness to work (cumulative incidence 4%) with no difference between drivers and other occupations, despite greater blood pressure and body mass index (BMI) in the former at baseline. Age (HR 1.13 (95% CI 1.06;1.22) and BMI (HR 1.18 (95% CI 1.04;1.34)) were associated with a greater chance of having CVD, adjusted for lung function, baseline diagnoses, year of employment and baseline blood pressure. Narrowing the analysis to only men, drivers, smokers and even middle-altitude residents did not change the effect. CONCLUSION: These findings confirmed high efficacy of pre-employment screening limiting access of workers with advanced conditions to work which later yielded low CVD incidence. In addition to conventional contraindications to work at high altitude, age and high BMI should be considered when a decision is made.

Occupational multimorbidity in the nickel industry workers.

The purpose of the study was to obtain new data on the causes, development, prevalence and nature of occupational multimorbidity in the nickel industry workers. We extracted data from the register of occupational disease and intoxication cases in the population of the Murmansk region and the Krasnoyarsk Territory in 2007-2021. In 2007-2021, 24.6% of nickel industry workers with newly diagnosed occupational diseases developed a multimorbid pathology. Its prevalence rose from 0% in 2007 to 83.3% in 2021, and the number of occupational diseases increased by 3.17 times. Two diagnoses were found in 66 (14.9%), three in 22 (5.0%), four in fifteen (3.4%), five in eleven (2.5%), and six in three (0.7%) employees. Respiratory and musculoskeletal diseases were the most prevalent disorders, accounting for 31.5% and 23.0% of cases, respectively. Occupational multimorbidity resulted from the increased combined exposure to occupational hazards, outdated technological processes, and the working conditions in the finished product cleaners and crane operators. Multimorbid diseases can be better prevented with improvement in working conditions and better quality of periodic medical examinations.