Background: Ambient and household air pollution remain leading risk factors for global morbidity and mortality. Exposure to fine particulate matter (PM₂.₅) is associated with increased risks of cardiovascular and respiratory diseases, as well as lung cancer, metabolic and neurological disorders, and immune dysfunction. In urban areas of Mongolia, air pollution reaches critical levels during the winter season. Although improved solid fuels have been introduced in recent years, their impact on both outdoor and indoor air quality remains insufficiently characterized. Aim: To compare outdoor and household air pollution levels in Ulaanbaatar and Darkhan cities. Materials and Methods: Outdoor air pollution data for Ulaanbaatar were obtained from fixed monitoring stations of the National Agency for Meteorology and Environmental Monitoring for the period 2014–2026, with seasonal comparisons performed. For indoor air quality assessment, a longitudinal study was conducted among 240 households (apartments, houses, and traditional gers) in Ulaanbaatar and Darkhan from 2023 to 2026. PM₂.₅ concentrations were measured using real-time sensors (PurpleAir sensor), deployed for 14–21 days per season (winter and summer) in each household, recording data at 10-minute intervals over 24-hour periods. Result: Between 2014 and 2026, the 24-hour mean concentrations in Ulaanbaatar were 60.5 µg/m for PM₂.₅, 117.3 µg/m for PM₁₀, 37.3 µg/m for NO₂, 41.8 µg/m for SO₂, and 27.5 µg/m for O₃. While particulate matter levels showed a decreasing trend following the introduction of improved fuels, SO₂ concentrations increased, and overall pollution levels remained higher than those observed in Darkhan. Indoor PM₂.₅ concentrations were higher in Ulaanbaatar compared to Darkhan (60.7±86.1 vs 48.4±96.7 µg/m). Significant differences were observed by housing type (p<0.0001), with higher concentrations in households using solid fuels (houses and gers) and lower levels in apartments. These findings indicate substantial variability in indoor air pollution by city, housing type, and season, with persistently elevated exposure levels. Conclusion Outdoor air pollutant concentrations in Ulaanbaatar, including particulate matter, NO₂, and SO₂, exceed national standards and WHO guideline values by 1–4 times. Indoor PM₂.₅ pollution is higher in Ulaanbaatar than in Darkhan and varies significantly by housing type and season, indicating a high and heterogeneous exposure burden among urban populations.

Background: According to the World Health Organization (WHO), 99 percent of the world’s population is exposed to air that exceeds WHO recommendations, with low- and middle-income countries being the most affected. The main causes of indoor air pollution include human activities such as fuel burning, cooking, cleaning, and smoking; housing characteristics such as walls, floors, ceilings, and furniture; ventilation; and outdoor air pollution. Aim : To assess PM1 and PM10 concentrations in 120 selected households in Ulaanbaatar. Materials and Methods : Indoor PM1 and PM10 concentrations were measured using Purple Air real-time sensors in randomly selected Ulaanbaatar households between October 2023 and January 2024. Supplementary data on factors affecting the PM2.5 concentration were collected via questionnaires. Each measurement was taken in 10-minute intervals, yielding 51,309 data for analysis. Results : PM1 concentrations were measured at 55.5±53.2 μg/m³ in gers, 54.9 ± 46.7 μg/m³ in houses, and 31.6±40.1 μg//m³ in apartments (p<0.001) and measuring PM10 concentrations were 110.6±108.6 μg/m³ in gers, 110.6±96.7 μg/m³ in houses, and 62.2±83.0 μg/m³ in apartments (p<0.001) When considering the concentration of PM1, PM10 by heating type, PM1 was 55.3±50.1 μg/m³ and PM10 was 110.6±103.0 μg/m³ in households with stoves and furnaces, and PM1 was 31.6±40.1 μg/m³ and PM10 was 62.2±83.0 μg/m³ in households connected to the central heating system (p<0.001). Regarding the months of measurement, the highest concentration was observed in December 2023, at 77.1±94.1 μg/m³. The highest concentrations for both PM₁ and PM₁₀ were recorded in January 2024, at PM₁: 64.8±55.1 μg/m³, PM₁₀: 131.4±116.0 μg/m³. Conclusion 1. Indoor PM10 concentrations in residential environments in Ulaanbaatar city were within the MNS4585:2016 Air Quality Standard, however, it was exceeded the WHO air quality guidelines, indicating an excessive risk of increasing morbidity and mortality among the population. 2. Indoor PM1 and PM10 concentrations in residential environments in Ulaanbaatar varies depending on location, type of housing, type of heating, and month of measurement.

Background: According to the World Health Organization (WHO), air pollution was responsible for 8.1 million deaths globally in 2021, making it the second leading cause of death, including among children under 5 years old. Air pollution is also linked to a range of diseases such as stroke, chronic obstructive pulmonary disease, lung cancer, and asthma. In Ulaanbaatar, the capital of Mongolia, the average daily concentration of PM2.5 particles in the air reaches 750 μg/m3 during winter, which is 50 times higher than the WHO’s recommendation, making it one of the most polluted cities in the world. Air pollution continues to pose a significant public health challenge not only in Mongolia but also in many countries globally. However, there is a lack of comprehensive research and studies that summarize and review the existing work in this field. Aim: To summarize and review thematic works on air pollution conducted by researchers from Mongolian universities. Materials and Methods: A systematic review and analysis were performed on thematic works by researchers who completed their master’s and doctoral degrees in the field of air pollution between 2011 and 2024. Results: In terms of the type of master’s and doctoral dissertations, 76.0% (n=19) were master’s theses and 24.0% (n=6) were doctoral dissertations. Among the total number of works included in the study, 36.0% (n=9) focused on the health effects of air pollution, while 64.0% (n=16) addressed other related areas. Some studies indicated that PM2.5 levels in the air between 2011 and 2024 were 1-6 times higher than the Mongolian standard, with the highest levels observed from November to February and the lowest in July. Additionally, some studies suggested a reduction in PM2.5 levels following the introduction of improved fuel in Ulaanbaatar. Air pollution was found to increase the risk of respiratory and cardiovascular diseases, as well as cancer, and to contribute to reduced fetal weight. Conclusion When examining thematic studies on air pollution conducted by state-owned universities in Mongolia, the primary focus has been on the composition, concentration, and health impacts of air pollution. Going forward, research aimed at mitigating air pollution should be driven by collaborative efforts and leadership from universities, with the results being effectively communicated to policymakers.

Background: Particulate matter in ambient air is an important risk factor for cardiovascular and respiratory diseases. Accurate and appropriate air quality monitoring is therefore critical for public health. In this context, it is necessary to investigate the feasibility of using low-cost direct monitoring devices (such as PurpleAir) in outdoor environments during the winter season, particularly in urban areas where fixed monitoring stations are not available. Aim: To assess and compare the outdoor PM2.5 concentrations in Ulaanbaatar and Darkhan during the winter season. Materials and Methods: The study was conducted in the capital city of Mongolia. The data collected for 45 days during the winter season, from December 9, 2024 to February 14, 2025. Continuous low-cost sensor was collected using a light scattering device (PurpleAir Classic) at a total of 25 locations and for 24 hours. Of these, 1 location was located next to a fixed measurement point and 3 locations (Zuun 4 zam, Yarmag, Selbe) were located within 200m of the study area, and the measurement results were compared using PM2.5. We used R software for statistical analysis. Results: The average PM2.5 concentration measured at the 13 fixed monitoring sites during the study period was 65 μg/ m³, while the average from the 25 PurpleAir sensors was 88 μg/m³. Parallel measurements conducted with the PurpleAir sensors and the UB4 fixed monitoring station showed a moderate correlation (r=0.44, R²=0.22, p<0.05). The measurement results at the Zuun 4 zam, Yarmag, and Selbe locations have a moderate correlation (r=0.38, r=0.61, r=0.25). Conclusion In situations where it is not possible to measure PM2.5 particulate matter in outdoor air automatically or by conventional methods, it is possible to monitor air quality by measured by low-cost sensors.

Background: It is stated in the Government Programme of 2016-2020 that public servants, including health care workers, shall be given a gradually increased salary based on their skill, dexterity, workload, and productivity, and such increase started from 2018 as planned. In the health sector of our country, regarding demand and regulation of the programme, the change shall be made that the system for median salary of physicians and overall staff employed at hospitals gets even constructive, and the required human resource for the sector shall be prepared. Thus, inferring from these claims, median salary, real wage, and socioeconomic condition are in critical need for further evaluation. Objective: To examine the current socio-economic condition of health care workers, and to study the influencing factors at play. Methods: In this study, we used quantitative and qualitative methods. In the survey, we involved 655 health care workers from 6 family health centers, 2 district hospitals, 3 health centers (district-based) in Songinokhairkhan, Sukhbaatar, and Baganuur districts; and Provincial hospital, regional diagnosis and health center, 16 soum health centers from Khovd, Uvs, Arkhangai, Bulgan, Khentii, Dornod, Umnugovi, and Dornogovi provinces, along with 3 National specialized health centers and 1 National central hospital. As for data gathering for the qualitative analysis, 30 focus group interviews and 47 key informant interviews were conducted for the purpose of examining socioeconomic condition, real wage sufficiency of health care workers. Results: Average household income of study participants was 1,880,269 tugrik, the real wage was 1,073,065 tugrik, and the overall household is seen to be composed of 2 different sources on average, namely, self-wage and the income coming from family members or supplement of Child Money Programme. It has come to notice that 19.5% of the participants have lower than average living standard, 89.2% have 2 different loans (mortgage, auto loan or mobile application based loans). Material deprivation index is seen to be 2.73, hence deemed as insufficient. In order to increase the real wage of those workers, it shall be taken into consideration that the basic salary is low, and some financial supplements need to be given. Furthermore, the performance based funding system of health sector is seen to be in need of improvement. Conclusion Real wage of the health care workers is, thus, insufficient. The fact that one in every five workers in this sector have lower than average living standard, and the material deprivation index is 2.73 implying that the financial lives of health care workers are immensely fragile.

Background: Psychosocial work environment predicts a range of health risks including sickness absence, poor self rated health, and depression. Objective: To identify association between psychosocial work environment and health related indicators among health care workers in Mongolia Methods: A cross-sectional study was conducted between January and April, 2023. 655 health care workers from Ulaanbaatar city and 4 aimags were involved. Psychosocial work environment was assessed by the Effort-reward imbalance model. As for the health related indicators, we used the SF-12 questionnaire and sickness absence report. Descriptive and inferential statistical analyses were performed.
The study was approved by Medical Ethics Review Committee on January 18, 2023 (#23/02). Results: 1 in every 2 health care workers experience effort-reward imbalance at work and rated their health as poor. In average, 32.7 percent of the study participants took 16.6 sick days for the last 1 year. The study identified poor physical (44.7±8.6) and mental health functioning (42.1±9.8) among study participants. Physical functioning was lower among nurses whereas mental health functioning was lower among physicians. Conclusion Poor health related indicators among health care workers are associated with adverse psychosocial work environment such as effort-reward imbalance and high effort and low reward

Background: The American Heart Association estimates that more than 1 million people die each year from acute coronary heart disease and half a million from acute coronary syndrome, and that $ 115 billion a year is spent on diagnosing and treating coronary heart disease [Word Health Organization, 2013]. Goal: In this study we aimed to using coronary computed tomography angiography (CCTA) to diagnose unstable plaques in coronary artery disease. Material and methods: From 2018 to 2021, we performed a coronary computed tomography angiography (CCTA) scan with a Philips Ingenuity 64-slice computed tomography (64 MD-CT) device and examined 47 patients diagnosed with unstable coronary artery disease at the Reference centre on Diagnostic Imaging named after R.Purev State Laureate, People’s physician and Honorary professor of the State Third Central Hospital.
Common statistical measurements such as means and standard errors were calculated. Probability of results were checked using Student’s test. Result: In studying signs of coronary computed tomography angiography (CCTA) to diagnose unstable plaques in coronary artery disease that coronary artery diameters more widening to compared healthy artery 16(34.0%±6.9), low density sites clarify in plaque (lower than +30HU)- 14(29.8%±6.7), small calcification detect in plaque 36 (74.5%±6.4), ring liked additional density (lower than +130 HU) sees in edge of plaque (Halo sign)-9(19.2%±5.8), plaque edge roughness, erosion liked changes- 18 (38.3%±7.1), rupture of intima (dissection)- 8(17.0%±5.5). Conclusion We detect that computed tomography angiography (CCTA)’s specific signs of unstable plaque of coronary artery disease are coronary artery diameters widening, low density sites clarify in plaque (lower than +30HU), small calcification detect in plaque, ring liked additional density (lower than +130 HU) sees in edge of plaque (Halo sign), plaque edge roughness, erosion liked changes and rupture of intima.

Background: Lower extremity arterial diseases are chronic stenosis of the artery and occlusive arterial diseases, which are commonly caused by atherosclerosis. Prevalence of lower extremity arterial diseases has positive proportional relationship with age of the patients. Furthermore, prevalence of lower extremity arterial disease is 16% among the males over the age of 60, whereas prevalence among same aged woman is 13%. Among the age group of 38 to 59 age, 60 to 69 age and 70-82 age group, prevalence of lower extremity arterial disease was 5.6%, 15.9%, and 33.8%, respectively. Goal: Identifying lower extremity arterial occlusive disease and chronic stenosis of arteries by CTA-TASC classification of aorta-iliac and femoral popliteal lesions. Obiective:
1. To identify age and sex of the patients with lower extremity arterial occlusive disease and chronic stenosis of arteries.
2. To identify lower extremity arterial occlusive disease and chronic stenosis of arteries by CTA-TASC classification of aorta-iliac and femoral popliteal lesions. Material and methods: Study sample consisted of 237 patients, who were diagnosed with lower extremity arterial occlusive disease and chronic stenosis of arteries from 2019 to 2020 at reference centre on Diagnostic Imaging na after R.Purev State Laureate, People’s physician and Honorary professor of the State Third Central Hospital. Computed angiogram images of lower extremity arteries were examined. Contrast agent “Ultravist” was pumped by automatic syringe. Lower extremity arterial occlusive disease and chronic stenosis of arteries are categorized by CTA-TASC classification of аorta-iliac and femoral popliteal lesions. The youngest participant was 20 years old and the oldest participant was 76 years old. Common statistical measurements such as means and standard errors were calculated. Probability of results were checked using Student’s test. Results: We have found following results: 185(78.1%±3.0) cases out of 237 diagnosed patients with lower extremity arterial occlusive disease and chronic stenosis of arteries are males and 52(21.9%±3.0) cases are female. Distribution of lower extremity arterial occlusive disease and chronic stenosis of arteries by the age group of patients are: up to 20 years of age is 3 (1.3%±0.7), 21 to 40 years of age is 14(5.9%±1.5), 41 to 60 years of age is 86(36.3%±3.1) and over the age of 61 is 134(56.5%±3.2). It is statistically highly significant that experiencing lower extremity arterial occlusive disease and chronic stenosis of arteries among the age group of over 61(P<0.001).
The result of lower extremity arterial occlusive disease and chronic stenosis of arteries by the CTA-TASC classification of aorta-iliac and femoral popliteal lesions are: CTA-TASS аorta-iliac lesions A-16(6.8%±1.8), B-8(3.4%±1.2), C-12(5.1%±1.4), D-41(17.3%±2.5), CTA-TASS femoral popliteal A-41(17.29%±2.5), B-53(22.36%±3.6), C-47(19.83%±2.6), D-96(40.5%±3.2), respectively. Conclusions
1. Lower extremity arterial occlusive disease and chronic stenosis of arteries occurs 46.5% over the age of 60 and 78.1% of the patients are males.
2. Following two categories have identified more than the rest, 17.3% CTA-TASC classification of аorta-iliac lesions, type D and 23.3% CTA-TASC classification of femoral popliteal lesions, type D.

Introduction: In 2018, the overall colorectal cancer (CRC) incidence rate was 3.6%, according to the National Cancer Center of Mongolia (NCCM), and the incidence of colorectal cancer has increased slightly in recent years. According to cancer stages, late stage cancer has a 5-year survival rate of 51%, while early stage cancer has a 5-year survival rate of 79%. The overall survival rate of colorectal cancer in Mongolia has not been studied in precisely. In Asia, the 5-year survival rate for colorectal cancer was 60%. Therefore, this study investigated the colorectal cancer survival rate and prognostic factors at NCCM. Methods: A total of 108 patients diagnosed with CRC at NCCM’s General Surgery Department from 2013 to 2015 were used in this retrospective cohort study. The Kaplan-Meier method was used to develop the survival graphs, which were then compared using the Log-rank test. Results: The median survival time was 42 months, with a 95% CI (38.55-45.66). A 5-year period, the overall survival rate for CRC was 61.2%. Survival rates at the I, II, III, and IV stages were 100%, 75%, 65.4%, and 13.5%, respectively. There was a significant difference in CRC survival rates across all stages (p=0.0001). There was a statistically significant difference in determining the relationship between adjuvant chemotherapy and survival rate (p=0.0003). Conclusion The outcome of the surgery is determined by the CRC stage. The postoperative survival rate (61.2%) is directly related to tumor stage, peripheral glandular metastasis, distant metastasis, and chemotherapy effects.

Purpose: The etiology of Legg-Calve-Perthes disease (LCPD) remains unknown until today. A few studies have suggested passive smoke inhalation may be a risk factor, although the association is not confirmed and a causal relationship has not been established. Most mothers who smoke during pregnancy may continue smoking after giving a birth, it would be difficult to determine to what extent passive smoke inhalation adds to the risk of LCPD in these children. The causes of Legg-Calve-Perthes disease are largely unknown, but this pediatric disease seems to result from interruption of the blood supply to the proximal femur and is considered a vascular disease. Because maternal smoking during pregnancy influences fetal development and is associated with cardiovascular diseases in offspring, we hypothesized that this exposure and passive Tabaco smoke exposure are risk factors for Legg-Calve-Perthes disease and also investigated other markers of impaired fetal development and early-life exposures. Methods: We prospectively recruited total 96 patients, among those 32 patients with LCPD as a case group and 64 patients attending the hospital for other orthopedic complaints as control group. Conditional logistic regression was used to assess the association between the exposures and risk of LCPD. Results: The main risk factors for LCPD were family background, indoor use of a wood stove, having a family member who smoked indoors (passive smoke) and smoke during pregnancy. Children from the middle socioeconomic group appeared to be at a greater risk of developing LCPD. Conclusions This study provides further evidence that environmental tobacco smoke is associated with an increased risk of LCPD. Family background and exposure to wood smoke also appears to be risk factors. Maternal smoking during pregnancy and other factors indicated by impaired fetal development may be associated with an increased risk of Legg-Calvé-Perthes disease. However, it remains unclear why there are profound differences in the incidence of the disease between regions when the prevalence of smoking is comparable and why bilateral involvement is infrequent, and it needs further study.