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Antifibrinolytic Agents , Hematoma, Subdural, Chronic , Tranexamic Acid , Aged , Humans , Antifibrinolytic Agents/therapeutic use , Hematoma, Subdural, Chronic/surgery , Hematoma, Subdural, Chronic/drug therapy , Meta-Analysis as Topic , Postoperative Complications/prevention & control , Recurrence , Secondary Prevention/methods , Systematic Reviews as Topic , Tranexamic Acid/therapeutic useABSTRACT
Searching for similar images in archives of histology and histopathology images is a crucial task that may aid in patient tissue comparison for various purposes, ranging from triaging and diagnosis to prognosis and prediction. Whole slide images (WSIs) are highly detailed digital representations of tissue specimens mounted on glass slides. Matching WSI to WSI can serve as the critical method for patient tissue comparison. In this paper, we report extensive analysis and validation of four search methods bag of visual words (BoVW), Yottixel, SISH, RetCCL, and some of their potential variants. We analyze their algorithms and structures and assess their performance. For this evaluation, we utilized four internal datasets (1269 patients) and three public datasets (1207 patients), totaling more than 200, 000 patches from 38 different classes/subtypes across five primary sites. Certain search engines, for example, BoVW, exhibit notable efficiency and speed but suffer from low accuracy. Conversely, search engines like Yottixel demonstrate efficiency and speed, providing moderately accurate results. Recent proposals, including SISH, display inefficiency and yield inconsistent outcomes, while alternatives like RetCCL prove inadequate in both accuracy and efficiency. Further research is imperative to address the dual aspects of accuracy and minimal storage requirements in histopathological image search.
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During acetabular cup positioning, intraoperative measurements of cup anteversion were taken using both fluoroscopy and navigation system. With the C-arm introduced at 40°, an anteroposterior view of the pelvis is taken. The C-arm is then centered over the hip, showing an anteverted cup with an approximate inclination of 40°. The axial C-arm is tilted away until the cup opening is visualized as a straight line, indicating that the beam of the fluoroscopy is aligned with the cup's anteversion. The tilt angle on the C-arm and anteversion reading on the navigation workstation were recorded. The high degree of agreement between fluoroscopic and navigation measurement of acetabular cup anteversion supports the use of fluoroscopy in settings with limited access to navigation systems in direct anterior total hip arthroplasty.
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Addressing the challenge of mapping hyperlocal air pollution in areas without local monitoring, we evaluated unsupervised transfer learning-based land-use regression (LUR) models developed using mobile monitoring data from other cities: CORrelation ALignment (Coral) and its inverse distance-weighted modification (IDW_Coral). These models mitigated domain shifts and transferred patterns learned from mobile air quality monitoring campaigns in Copenhagen and Rotterdam to estimate annual average air pollution levels in Amsterdam (50m road segments) without involving any Amsterdam measurements in model development. For nitrogen dioxide (NO2), IDW_Coral outperformed Copenhagen and Rotterdam LUR models directly applied to Amsterdam, achieving MAE (4.47 µg/m3) and RMSE (5.36 µg/m3) comparable to a locally fitted LUR model (AMS_SLR) developed using Amsterdam mobile measurements collected for 160 days. IDW_Coral yielded an R2 of 0.35, similar to that of the AMS_SLR based on 20 collection days, suggesting a minimum requirement of 20-day mobile monitoring to capture city-specific insights. For ultrafine particles (UFP), IDW_Coral's citywide predictions strongly correlated with previously published mixed-effect models fitted with 160-day Amsterdam measurements (Pearson correlation of 0.71 for UFP and 0.72 for NO2). IDW_Coral demands no direct measurements in the target area, showcasing its potential for large-scale applications and offering significant economic efficiencies in executing mobile monitoring campaigns.
Subject(s)
Air Pollutants , Air Pollution , Environmental Monitoring , Environmental Monitoring/methods , Particulate Matter , Nitrogen Dioxide/analysis , CitiesABSTRACT
Digital pathology and the integration of artificial intelligence (AI) models have revolutionized histopathology, opening new opportunities. With the increasing availability of whole-slide images (WSIs), demand is growing for efficient retrieval, processing, and analysis of relevant images from vast biomedical archives. However, processing WSIs presents challenges due to their large size and content complexity. Full computer digestion of WSIs is impractical, and processing all patches individually is prohibitively expensive. In this article, we propose an unsupervised patching algorithm, Sequential Patching Lattice for Image Classification and Enquiry (SPLICE). This novel approach condenses a histopathology WSI into a compact set of representative patches, forming a collage of WSI while minimizing redundancy. SPLICE prioritizes patch quality and uniqueness by sequentially analyzing a WSI and selecting nonredundant representative features. We evaluated SPLICE for search and match applications, showing its improved accuracy, reduced computation time, and storage requirements compared with existing state-of-the-art methods. As an unsupervised method, SPLICE effectively reduces storage requirements for representing tissue images by 50%. This reduction enables numerous algorithms in computational pathology to operate much more efficiently, paving the way for accelerated adoption of digital pathology.
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Introduction: Lung cancer remains a global health concern, with non-small cell lung cancer (NSCLC) comprising the majority of cases. Early detection of lung cancer has led to an increased number of cases identified in the earlier stages of NSCLC. This required the revaluation of the NSCLC treatment approaches for early stage NSCLC. Methods: We conducted a comprehensive search using multiple databases to identify relevant studies on treatment modalities for early stage NSCLC. Inclusion criteria prioritized, but were not limited to, clinical trials and meta-analyses on surgical approaches to early stage NSCLC conducted from 2021 onwards. Discussion: Minimally invasive approaches, such as VATS and RATS, along with lung resection techniques, including sublobar resection, have emerged as treatments for early stage NSCLC. Ground-glass opacities (GGOs) have shown prognostic significance, especially when analyzing the consolidation/tumor ratio (CTR). There have also been updates on managing GGOs, including the non-surgical approaches, the extent of lung resection indicated, and the level of lymphadenectomy required. Conclusions: The management of early stage NSCLC requires a further assessment of treatment strategies. This includes understanding the required extent of surgical resection, interpreting the significance of GGOs (specifically GGOs with a high CTR), and evaluating the efficacy of alternative therapies. Customized treatment involving surgical and non-surgical interventions is essential for advancing patient care.
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Hepatic cancer is widely regarded as the leading cause of cancer-related mortality worldwide. Despite recent advances in treatment options, the prognosis of liver cancer remains poor. Therefore, there is an urgent need to develop more representative in vitro models of liver cancer for pathophysiology and drug screening studies. Fortunately, an exciting new development for generating liver models in recent years has been the advent of organoid technology. Organoid models hold huge potential as an in vitro research tool because they can recapitulate the spatial architecture of primary liver cancers and maintain the molecular and functional variations of the native tissue counterparts during long-term culture in vitro. This review provides a comprehensive overview and discussion of the establishment and application of liver organoid models in vitro. Bioengineering strategies used to construct organoid models are also discussed. In addition, the clinical potential and other relevant applications of liver organoid models in different functional states are explored. In the end, this review discusses current limitations and future prospects to encourage further development.
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Ultrafine particles (UFPs) are airborne particles with a diameter of less than 100 nm. They are emitted from various sources, such as traffic, combustion, and industrial processes, and can have adverse effects on human health. Long-term mean ambient average particle size (APS) in the UFP range varies over space within cities, with locations near UFP sources having typically smaller APS. Spatial models for lung deposited surface area (LDSA) within urban areas are limited and currently there is no model for APS in any European city. We collected particle number concentration (PNC), LDSA, and APS data over one-year monitoring campaign from May 2021 to May 2022 across 27 locations and estimated annual mean in Copenhagen, Denmark, and obtained additionally annual mean PNC data from 6 state-owned continuous monitors. We developed 94 predictor variables, and machine learning models (random forest and bagged tree) were developed for PNC, LDSA, and APS. The annual mean PNC, LDSA, and APS were, respectively, 5523 pt/cm3, 12.0 µm2/cm3, and 46.1 nm. The final R2 values by random forest (RF) model were 0.93 for PNC, 0.88 for LDSA, and 0.85 for APS. The 10-fold, repeated 10-times cross-validation R2 values were 0.65, 0.67, and 0.60 for PNC, LDSA, and APS, respectively. The root mean square error for final RF models were 296 pt/cm3, 0.48 µm2/cm3, and 1.60 nm for PNC, LDSA, and APS, respectively. Traffic-related variables, such as length of major roads within buffers 100-150 m and distance to streets with various speed limits were amongst the highly-ranked predictors for our models. Overall, our ML models achieved high R2 values and low errors, providing insights into UFP exposure in a European city where average PNC is quite low. These hyperlocal predictions can be used to study health effects of UFPs in the Danish Capital.
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Air Pollutants , Air Pollution , Humans , Air Pollutants/analysis , Particulate Matter/analysis , Particle Size , Cities , Lung/chemistry , Environmental Monitoring , Air Pollution/analysisABSTRACT
BACKGROUND: Left atrial appendage closure (LAAC) is a treatment modality for stroke prevention in patients with atrial fibrillation (AF). One of the potential complications of LAAC is a peri-device leak (PDL), which could potentially increase the risk of thromboembolism formation. METHODS: This systematic review was done according to PRISMA guidelines. Using four databases, all primary studies through April 2022 that met selection criteria were included. Outcomes of interest were studies reporting on PDL characteristics, risk factors and management. RESULTS: A total of 116 studies met selection criteria (97 original studies and 19 case reports/series). In the original studies (n = 30,133 patients), the weighted mean age was 72.0 ± 7.4 years (57% females) with a HAS-BLED and CHA2DS2-VASc weighted means of 2.8 ± 1.1 and 3.8 ± 1.3, respectively. The most common definition of PDL was based on size; 5 mm: major, 3-5 mm: moderate, < 1 mm minor, or trivial. Follow up time for PDL detection was 7.15 ± 9.0 months. 33% had PDL, irrespective of PDL severity/size, and only 0.9% had PDL of greater than 5 mm. The main risk factors for PDL development included lower degree of over-sizing, lower left ventricular ejection fraction, device/LAA shape mismatch, previous radiofrequency ablation, and male sex. The most common methods to screen for PDL included transesophageal echocardiogram and cardiac CT. PDL Management approaches include Amplatzer Patent Foramen Ovale occluder, Hookless ACP, Amplatzer vascular plug II, embolic coils, and detachable vascular coils; removal or replacement of the device; and left atriotomy. CONCLUSION: Following LAAC, the emergence of a PDL is a significant complication to be aware of. Current evidence suggests possible risk factors that are worth assessing in-depth. Additional research is required to assess suitable candidates, timing, and strategies to managing patients with PDL.
Subject(s)
Atrial Appendage , Atrial Fibrillation , Humans , Atrial Appendage/surgery , Atrial Appendage/diagnostic imaging , Atrial Fibrillation/surgery , Risk Factors , Postoperative Complications/prevention & control , Septal Occluder Device , Female , Stroke/prevention & control , Stroke/etiology , Male , Left Atrial Appendage ClosureABSTRACT
AIMS: The three correlated environmental exposures (air pollution, road traffic noise, and green space) have all been associated with the risk of myocardial infarction (MI). The present study aimed to analyse their independent and cumulative association with MI. METHODS AND RESULTS: In a cohort of all Danes aged 50 or older in the period 2005-17, 5-year time-weighted average exposure to fine particles (PM2.5), ultrafine particles, elemental carbon, nitrogen dioxide (NO2), and road traffic noise at the most and least exposed façades of residence was estimated. Green space around residences was estimated from land use maps. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence interval (CI), and cumulative risk indices (CRIs) were calculated. All expressed per interquartile range. Models were adjusted for both individual and neighbourhood-level socio-demographic covariates. The cohort included 1 964 702 persons. During follow-up, 71 285 developed MI. In single-exposure models, all exposures were associated with an increased risk of MI. In multi-pollutant analyses, an independent association with risk of MI was observed for PM2.5 (HR: 1.026; 95% CI: 1.002-1.050), noise at most exposed façade (HR: 1.024; 95% CI: 1.012-1.035), and lack of green space within 150 m of residence (HR: 1.018; 95% CI: 1.010-1.027). All three factors contributed significantly to the CRI (1.089; 95% CI: 1.076-1.101). CONCLUSION: In a nationwide cohort study, air pollution, noise, and lack of green space were all independently associated with an increased risk of MI. The air pollutant PM2.5 was closest associated with MI risk.
The present study aimed to analyse their independent and cumulative association of the three correlated environmental exposures: air pollution, road traffic noise, and green space with MI. Air pollution, noise, and lack of green space were all independently associated with MI.Risk estimates for air pollution, noise, and lack of green space were similar, indicating that all may be equally relevant targets for regulatory measures.
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Air Pollutants , Air Pollution , Myocardial Infarction , Humans , Noise/adverse effects , Cohort Studies , Parks, Recreational , Air Pollution/adverse effects , Air Pollutants/adverse effects , Myocardial Infarction/diagnosis , Myocardial Infarction/epidemiology , Myocardial Infarction/etiology , Particulate Matter/adverse effects , Environmental Exposure/adverse effects , Denmark/epidemiologyABSTRACT
BACKGROUND: Chronic subdural hematoma (CSDH) is a frequently encountered neurosurgical disease among the elderly. The mainstay treatment involves surgical evacuation, but recurrence rates of approximately 13% pose complications. Adjuvant treatments, including tranexamic acid (TXA), have been explored, yet consensus on their efficacy and safety in elderly patients remains uncertain. The study aims to examine the role of TXA as adjunctive therapy in reducing CSDH recurrence and explore any potential association between TXA use and thrombotic events in this patient population. METHODS: The systematic review and meta-analysis adhered to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Cochrane Handbook standards, searching databases up to July 2023 for randomized controlled trials and propensity-matched cohorts evaluating adjuvant TXA. The primary outcome was CSDH recurrence, and the secondary outcome was thrombosis risk, measured as relative risks. RESULTS: A total of 6 studies were included, comprising 1403 patients with CSDH who underwent surgical treatment. Four studies were randomized controlled trials, while the other 2 were propensity-matched cohorts. The overall pooled relative risk for CSDH recurrence in the TXA group compared to the control group was 0.41 (95% confidence interval [0.29-0.59], P < 0.01), indicating a significant reduction in recurrence with TXA treatment. CONCLUSIONS: In conclusion, our study indicates that adjuvant TXA may help reduce CSDH recurrence in elderly patients undergoing surgical treatment. However, the study has limitations and there is a need for further research to validate these findings.
Subject(s)
Antifibrinolytic Agents , Hematoma, Subdural, Chronic , Recurrence , Tranexamic Acid , Humans , Hematoma, Subdural, Chronic/surgery , Hematoma, Subdural, Chronic/drug therapy , Tranexamic Acid/therapeutic use , Antifibrinolytic Agents/therapeutic use , Aged , Postoperative Complications/prevention & control , Randomized Controlled Trials as Topic , Aged, 80 and overABSTRACT
BACKGROUND AND AIM: While proton pump inhibitor (PPI) therapy has proven to be effective in managing gastroesophageal reflux disease (GERD), a notable portion of patients who experience GERD symptoms may not respond to this treatment. Research suggests that roughly 30% of individuals with a presumed GERD diagnosis may continue to experience symptoms, whether partially or completely, even when receiving PPI therapy. The aim of this study was to assess the treatment of gastrointestinal diseases with a novel potassium-competitive acid blocker (P-CAB), vonoprazan, in terms of its effectiveness and safety in the Pakistani population. METHODS: This prospective, multicenter, observational study was conducted in Pakistan. This study included 1,642 patients from January 2023 to August 2023, aged 18 years, with gastrointestinal disorders. All demographic data, medical history, GERD severity assessment questionnaire (GerdQ), and laboratory parameters, including stool assessment for Helicobacter pylori (H. pylori), were observed. Patients were orally treated with vonoprazan at doses of 10 mg or 20 mg, once or twice daily. Statistical analysis was done by one-way ANOVA. RESULTS: Out of 1,642 patients, 840 (51.2%) were males and 802 (48.8%) were females, with a mean age of 39.81±14.61 years. The mean GerdQ score at baseline was 20.37±15.87, 7.24±8.15 at the second week of treatment, and 3.70±6.31 at the fourth week of treatment (p<0.001). 90.74% of patients achieved H. pylori eradication. Most patients were acid regurgitation and heartburn-free for >70% of days. Most of the patients, 1,283 (78.13%), exhibited good treatment compliance. Mild adverse events were reported in 37 (2.3%) patients. CONCLUSIONS: The use of vonoprazan significantly reduced the likelihood of GERD by improving symptoms and was also highly effective in the elimination of H. pylori infections. Vonoprazan was generally well tolerated.
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Introduction and aim Medication errors (MEs) pose a severe threat in the medical field. Since such errors are preventable, it is paramount for all healthcare workers to be educated on the matter. This study aimed to assess medical interns' attitudes and knowledge of medication safety and errors. We also aimed to validate current university programs to educate students about medication safety and errors. Methods A cross-sectional study that utilized a self-administered online questionnaire comprised 31 questions. The questionnaire was distributed via social media networks, such as WhatsApp, Twitter, email, Instagram, and Snapchat among 100 medical, pharmacy, and nursing interns in Saudi Arabia. The study population included both Saudi and non-Saudi interns. Results The majority of participants, comprising 92% (n=92), indicated that they were familiar with the definition of medication errors (ME). Additionally, 85% (n=85) expressed their willingness to report instances of MEs when medications were not prescribed but required. Moreover, 90% (n=90) of the surveyed individuals expressed their willingness to report MEs in situations where patients did not receive medications as prescribed. In cases where patients experienced harm and required treatment due to an ME, 91% (n=91) of respondents committed to reporting such incidents. A total of 52 (52%) respondents stated that they would report MEs regardless of whether they reached/harmed the patient. A good ME knowledge level was observed in 48% of respondents. A higher likelihood of good ME knowledge was significantly associated with safety reporting system (SRS) awareness and reporting MEs regardless of whether they reached/harmed the patient (p<0.05). College, awareness/attitude, or other demographic factors were not significantly related to ME knowledge (p>0.05). Conclusion This study showed that although interns in the healthcare field do have some knowledge about MEs, there is still a significant need to improve their knowledge. This can be achieved through various ways, one of which is by implementing this topic into the university curricula.
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Neutrophils are the most abundant of the circulating immune cells and are the first to be recruited to sites of inflammation. Neutrophils are a heterogeneous group of immune cells from which are derived extracellular traps (NETs), reactive oxygen species, cytokines, chemokines, immunomodulatory factors, and alarmins that regulate the recruitment and phenotypes of neutrophils, macrophages, dendritic cells, T cells, and B cells. In addition, cytokine-stimulated neutrophils can express class II major histocompatibility complex and the internal machinery necessary for successful antigen presentation to memory CD4+ T cells. This may be relevant in the context of vaccine memory. Neutrophils thus emerge as orchestrators of immune responses that play a key role in determining the outcome of infections, vaccine efficacy, and chronic diseases like autoimmunity and cancer. This review aims to provide a synthesis of current evidence as regards the role of these functions of neutrophils in homeostasis and disease.
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Extracellular Traps , Neutrophils , Humans , Cytokines , Inflammation , MacrophagesABSTRACT
Objective: To verify the analytical performance of cobas® HBV PCR and cobas® HCV PCR assays with Abbott m2000 RealTime System as the reference method. Design: De-identified residual, archived patient specimens, and College of American Pathologists (CAP) proficiency testing samples were used. Analytical parameters verified were accuracy, precision, limit of detection (LOD), linear range, and cross-contamination. Experiments were designed in accordance with Clinical Laboratories Standards Institute (CLSI) guidelines and CAP standards. Analysis of accuracy was done through regression plots and Bland Altman analyses. Precision was analyzed through coefficient of variation and ANOVA; LOD through probit analysis; and linear range through polynomial fit analysis. Results: The regression plots for accuracy showed a slope nearing 1, with a y-intercept close to zero, while Bland Altman analyses also showed no systematic evidence of bias, though concordance of results was not perfect near the lower limit of quantification. Coefficients of variation were all below 15%, while ANOVA returned p-values above 0.99, indicating no statistically significant imprecision. The LOD verified were an order of magnitude higher than the manufacturer reported ones for both assays, while the linear range verified was more limited. Within the verified range, polynomial fit analysis showed line to be the best fit for the data. Conclusions: cobas® HBV PCR and cobas® HCV PCR assays showed acceptable accuracy, acceptable precision, as well as no evidence of cross-contamination. The LOD verified were higher, and linear ranges more limited than those reported by the manufacturer. Verifications of these may be limited by availability of appropriate testing specimens.
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AIMS: We provide an overview of nationwide environmental data available for Denmark and its linkage potentials to individual-level records with the aim of promoting research on the potential impact of the local surrounding environment on human health. BACKGROUND: Researchers in Denmark have unique opportunities for conducting large population-based studies treating the entire Danish population as one big, open and dynamic cohort based on nationally complete population and health registries. So far, most research in this area has utilised individual- and family-level information to study the clustering of disease in families, comorbidities, risk of, and prognosis after, disease onset, and social gradients in disease risk. Linking environmental data in time and space to individuals enables novel possibilities for studying the health effects of the social, built and physical environment. METHODS: We describe the possible linkage between individuals and their local surrounding environment to establish the exposome - that is, the total environmental exposure of an individual over their life course. CONCLUSIONS: The currently available nationwide longitudinal environmental data in Denmark constitutes a valuable and globally rare asset that can help explore the impact of the exposome on human health.
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BACKGROUND: Ambient air pollution exposure has been associated with childhood asthma, but previous studies have primarily focused on prevalence of asthma and asthma-related outcomes and urban traffic-related exposures. OBJECTIVE: We examined nationwide associations between pre- and postnatal exposure to ambient air pollution components and asthma incidence in children age 0-19 y. METHODS: Asthma incidence was identified from hospital admission, emergency room, and outpatient contacts among all live-born singletons born in Denmark between 1998 and 2016. We linked registry data with monthly mean concentrations of particulate matter (PM) with aerodynamic diameter ≤2.5µm (PM2.5) and PM with aerodynamic diameter ≤10µm (PM10), nitrogen dioxide (NO2), nitrogen oxides, elemental carbon, and organic carbon (OC), sulfur dioxide, ozone, sulfate, nitrate, ammonium, secondary organic aerosols, and sea salt. Associations were estimated with Cox proportional hazard models using fixed prenatal exposure means and time-varying postnatal exposures. RESULTS: Of the 1,060,154 children included, 6.1% had asthma during the mean follow-up period of 8.8 y. The risk of asthma increased with increasing prenatal exposure to all pollutants except for O3 and sea salt. We also observed increased risk after restriction to asthma after age 4 y, after additional adjustment for area-specific socioeconomic status, and for postnatal exposure to most pollutants. The hazard ratio (HR) associated with an interquartile range increase of 2.4 and 8.7 µg/m3 in prenatal exposure was 1.06 [95% confidence interval (CI): 1.04, 1.08] for PM2.5 and 1.04 (95% CI: 1.02, 1.05) for NO2, respectively. This association with PM2.5 was stable after adjustment for NO2, whereas it attenuated for NO2 to 1.01 (95% CI: 0.99, 1.03) after adjustment for PM2.5. For a 0.5-µg/m3 increase in prenatal OC exposure, for which biomass is an important source, the HR was 1.08 (95% CI: 1.06, 1.10), irrespective of adjustment for PM2.5. DISCUSSION: These findings suggest that early-life exposure to ambient air pollution from multiple sources contributes to asthma development. https://doi.org/10.1289/EHP11539.
Subject(s)
Air Pollutants , Air Pollution , Asthma , Environmental Pollutants , Prenatal Exposure Delayed Effects , Pregnancy , Female , Humans , Child , Infant, Newborn , Infant , Child, Preschool , Adolescent , Young Adult , Adult , Cohort Studies , Air Pollutants/analysis , Incidence , Prenatal Exposure Delayed Effects/chemically induced , Environmental Exposure/adverse effects , Air Pollution/adverse effects , Air Pollution/analysis , Asthma/chemically induced , Asthma/epidemiology , Particulate Matter/analysis , Nitrogen Dioxide/analysis , Carbon , Denmark/epidemiologyABSTRACT
Studies suggest a link between particulate matter less than or equal to 2.5 µm in diameter (PM2.5) and amyotrophic lateral sclerosis (ALS), but to our knowledge critical exposure windows have not been examined. We performed a case-control study in the Danish population spanning the years 1989-2013. Cases were selected from the Danish National Patient Registry based on International Classification of Diseases codes. Five controls were randomly selected from the Danish Civil Registry and matched to a case on vital status, age, and sex. PM2.5 concentration at residential addresses was assigned using monthly predictions from a dispersion model. We used conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for confounding. We evaluated exposure to averaged PM2.5 concentrations 12-24 months, 2-6 years, and 2-11 years pre-ALS diagnosis; annual lagged exposures up to 11 years prediagnosis; and cumulative associations for exposure in lags 1-5 years and 1-10 years prediagnosis, allowing for varying association estimates by year. We identified 3,983 cases and 19,915 controls. Cumulative exposure to PM2.5 in the period 2-6 years prediagnosis was associated with ALS (OR = 1.06, 95% CI: 0.99, 1.13). Exposures in the second, third, and fourth years prediagnosis were individually associated with higher odds of ALS (e.g., for lag 1, OR = 1.04, 95% CI: 1.00, 1.08). Exposure to PM2.5 within 6 years before diagnosis may represent a critical exposure window for ALS.