Category: Statistics

Physiol Meas. 2024 Jan 4. doi: 10.1088/1361-6579/ad1b10. Online ahead of print.

ABSTRACT

Smoking is widely recognized as a significant risk factor in the progression of arterial stiffness and cardiovascular diseases. Valuable information related to cardiac arrhythmias and heart function can be obtained by analyzing biosignals such as the electrocardiogram (ECG) and the photoplethysmogram (PPG). The PPG signal is a non-invasive optical technique that can be used to evaluate the changes in blood volume, and thus it can be linked to the health of the vascular system.

OBJECTIVE: In this study, the impact of three smoking habits -cigarettes, shisha, and electronic cigarettes (e-cigarettes)- on the features of the PPG signal were investigated.

APPROACH: The PPG signals are measured for 45 healthy smokers before, during, and after the smoking session and then processed to extract the morphological features. Quantitative statistical techniques were used to analyze the PPG features and provide the most significant features in the three smoking habits. The impact of smoking is observed through significant changes in the features of the PPG signal, indicating blood volume instability.

MAIN RESULTS: The results revealed that the three smoking habits influence the characteristics of the PPG signal significantly, which persist even after 15 minutes of smoking. Among them, shisha has the greatest impact on PPG features, particularly on heart rate, systolic time, augmentation index, and peak pulse interval change. In contrast, e-cigarettes have the least effect on PPG features. Interestingly, smoking electronic cigarettes, which many participants use as a substitute for traditional cigarettes when attempting to quit smoking, has nearly a comparable effect to regular smoking.

SIGNIFICANCE: The findings suggest that individuals who smoke shisha are more likely to develop cardiovascular diseases at an earlier age compared to those who have other smoking habits. Understanding the variations in the PPG signal caused by smoking can aid in the early detection of cardiovascular disorders and provide insight into cardiac conditions. This ultimately contributes to the prevention of the development of cardiovascular diseases and the development of a health screening system.

PMID:38176078 | DOI:10.1088/1361-6579/ad1b10

Aerosp Med Hum Perform. 2023 Dec 1;94(12):939-943. doi: 10.3357/AMHP.6342.2023.

ABSTRACT

INTRODUCTION: Management of aeromedical risk is essential for flight safety. Given the many operator stressors for pilots, militaries maintain a vested interest in selecting aircrew applicants who meet rigorous initial medical standards. Very little published literature exists regarding the extent of medical disqualifications or precluding conditions for initial candidates.METHODS: For the British Army, pilot selection is a phased, multistep process that includes Phase I medical screening followed by a comprehensive Phase II medical exam. De-identified summary data were retrospectively reviewed for medical fitness and disqualifying categories for the 5-yr period of 2018-2022, inclusive. For those ultimately deemed unfit for aviation service, etiology was grouped into general categories.RESULTS: Approximately one-third (30.2%) of candidates were disqualified at Phase I initial medical screening with leading categories of attrition due to respiratory etiology, especially a history of asthma or reactive airway disease, followed by ophthalmology. For the Phase II medical exam cohort, 21.0% were medically disqualified with most attrition from anthropometry and ophthalmology. There were no statistical differences in disqualifications for gender or pathway of entry (civilian vs. serving personnel).DISCUSSION: Major categories of medical attrition were similar to that of other nations, yet the published literature in this area is surprisingly tenuous. Given the desire for evidence-based medical selection standards, it is important for regular review of processes and standards such that the risks of known physiological challenges are judiciously weighed with the benefits of a large, diverse pool of selection as well as force structure and recruitment demand.Adams MS, Goldie CE, Gaydos SJ. Retrospective analysis of medical attrition for pilot applicants to the British Army Air Corps. Aerosp Med Hum Perform. 2023; 94(12):939-943.

PMID:38176043 | DOI:10.3357/AMHP.6342.2023

J Appl Clin Med Phys. 2024 Jan 4:e14258. doi: 10.1002/acm2.14258. Online ahead of print.

ABSTRACT

PURPOSE: We aimed to perform the commissioning and clinical evaluation of myQA SRS detector array for patient-specific quality assurance (PSQA) of stereotactic radiosurgery (SRS)/ stereotactic body radiotherapy (SBRT) plans.

METHODS: To perform the commissioning of myQA SRS, its dose linearity, dose-rate dependence, angular dependence, and field-size dependence were investigated. Ten SBRT plans were selected for clinical evaluation: 1) Common clinical deviations based on the original SBRT plan (Plan0), including multileaf collimator (MLC) positioning deviation and treatment positioning deviation were introduced. 2) Compared the performance of the myQA SRS and a high-resolution EPID dosimetry system in PSQA measurement for the SBRT plans. Evaluation parameters include gamma passing rate (GPR) and distance-to-agreement (DTA) pass rate (DPR).

RESULTS: The dose linearity, angle dependence, and field-size dependence of myQA SRS system exhibit excellent performance. The myQA SRS is highly sensitive in the detection of MLC deviations. The GPR of (3%/1 mm) decreases from 90.4% of the original plan to 72.7%/62.9% with an MLC outward/inward deviation of 3 mm. Additionally, when the setup error deviates by 1 mm in the X, Y, and Z directions with the GPR of (3%/1 mm) decreasing by an average of -20.9%, -25.7%, and -24.7%, respectively, and DPR (1 mm) decreasing by an average of -33.7%, -32.9%, and -29.8%. Additionally, the myQA SRS has a slightly higher GPR than EPID for PSQA, However, the difference is not statistically significant with the GPR of (3%/1 mm) of (average 90.4%% vs. 90.1%, p = 0.414).

CONCLUSION: Dosimetry characteristics of the myQA SRS device meets the accuracy and sensitivity requirement of PSQA for SRS/SBRT treatment. The dose rate dependence should be adequately calibrated before its application and a more stringent GPR (3%/1 mm) evaluation criterion is suggested when it is used for SRS/SBRT QA.

PMID:38175960 | DOI:10.1002/acm2.14258

Hum Vaccin Immunother. 2023 Dec 15;19(3):2278927. doi: 10.1080/21645515.2023.2278927. Epub 2023 Nov 21.

ABSTRACT

Varicella is an acute, highly contagious disease in susceptible individuals and is preventable through vaccination. This study aimed to determine the impact of varicella vaccination on hospitalizations and complications at a pediatric reference hospital in Panama before and after the vaccine introduction. This descriptive ecological study analyzed clinical records of patients diagnosed with varicella through a retrospective and interrupted time series analysis. An autoregressive integrated moving average model was built to compare the incidence rates observed after vaccination with those expected rates derived from the model. A statistical model was fitted to the observed interrupted time series data by regression and used to predict future trends. The mean difference in varicella hospital discharges before and after the introduction of the varicella vaccine was 47%. The rate of hospitalizations for varicella decreased to 52.3%. A declining trend in varicella hospitalizations was observed from 2015 after vaccine introduction in 2014. Complications in vaccinated patients were secondary skin and soft tissue infection, possibly due to bacterial superinfection. The impact of varicella vaccination on reducing varicella hospital discharges reported at a pediatric reference hospital in Panama was confirmed.

PMID:38175951 | DOI:10.1080/21645515.2023.2278927

Adv Mater. 2024 Jan 4:e2309351. doi: 10.1002/adma.202309351. Online ahead of print.

ABSTRACT

Tunnel oxide passivated contacts (TOPCon) have recently gained interest as a way to increase the energy conversion efficiency of silicon solar cells, and the International Technology Roadmap of Photovoltaics forecasts TOPCon to become an important technology despite a few remaining challenges. To review the recent development of TOPCon cells, we have compiled a dataset of all device data found in the current literature, which sums up to 405 devices from 131 papers. This may seem like a surprisingly small number of cells given the recent interest in the TOPCon architecture, but it illustrates a problem of data dissemination in the field. Notwithstanding the limited number of cells, there is a great diversity in cell manufacturing procedures, and we observe a gradual increase in performance indicating that the field has not yet converged on a set of best practices. By analyzing the data using statistical methods and machine learning (ML) algorithms, we were able to reinforces some commonly held hypotheses related to the performance differences between different device architectures. We also identify a few more unintuitive feature combinations that would be of interest for further experimentally studies. This work also aims to inspire improvements in data management and dissemination within the TOPCon community, which would further increase the value of statistical analysis like this as well as enable a larger part of the ML toolbox to be used. This article is protected by copyright. All rights reserved.

PMID:38175915 | DOI:10.1002/adma.202309351

MMWR Morb Mortal Wkly Rep. 2024 Jan 5;72(5253):1394. doi: 10.15585/mmwr.mm725253a6.

NO ABSTRACT

PMID:38175812 | DOI:10.15585/mmwr.mm725253a6

Interdiscip Cardiovasc Thorac Surg. 2024 Jan 4:ivae001. doi: 10.1093/icvts/ivae001. Online ahead of print.

ABSTRACT

OBJECTIVES: Despite robotic-assisted (RATS) lobectomy is on the rise in Europe, the majority of lobectomies in Germany are still performed with an open or thoracoscopic (VATS) approach. Empirical evidence in favour of RATS lobectomy is inconsistent. This retrospective cohort study investigates the impact of RATS lobectomy compared with OPEN (open thoracic surgery) and VATS lobectomy on short-term outcomes in Germany using multicentre real-world data.

METHODS: Anonymized routine data from Germany from 2018 to 2020 were retrospectively analyzed. These data were provided by 61 German hospitals. Propensity Score Matching (PSM) with subsequent Generalized Linear Models (GLM) was performed for statistical analysis. Additionally, in order to test the robustness of the results, multivariable regression analyses with cluster robust standard errors were used.

RESULTS: 2,498 patients with lobectomy were identified: In 1,345 patients OPEN, in 983 VATS and 170 a RATS lobectomy was performed. RATS-compared to OPEN and VATS-reduced length of stay by 28% or 4.2 days [CI: 2.9; 5.4] and by 13% or 1.6 days [CI: 0.2; 3.0], respectively. The risk of pneumonia was reduced by 5.3 percentage points in the RATS group compared to both OPEN and VATS (p = 0.07/0.01). RATS-compared to an open approach-reduces the risk of blood transfusions by 8.8 percentage points (p < 0.001) and length of stay on the ICU (p < 0.001).

CONCLUSION: This study provides strong support that RATS lobectomy outperforms OPEN or VATS lobectomy in terms of hospital length of stay, and short-term in-hospital postoperative complications in the real-world scenario in Germany.

PMID:38175785 | DOI:10.1093/icvts/ivae001

Eur J Cardiothorac Surg. 2024 Jan 4:ezad437. doi: 10.1093/ejcts/ezad437. Online ahead of print.

ABSTRACT

OBJECTIVES: To explore the prognostic value of brain computed tomography perfusion for postoperative new stroke in acute type A aortic dissection patients.

METHODS: Patients with acute type A aortic dissection and suspected cerebral malperfusion who underwent brain computed tomography perfusion and surgical repair were retrospectively analyzed. Brain perfusion was quantified mainly with the averaged cerebral blood flow. Significant clinical and imaging findings were identified through univariable and multivariable regression analysis. Furthermore, the added prognostic benefit of perfusion parameters was confirmed with the receiver-operating characteristic curves in the entire cohort and subgroup analysis.

RESULTS: The incidence of postoperative new stroke was 30.8% (44/143). The independent adjusted predictors of postoperative new stroke included an impaired averaged cerebral blood flow (mL/100 mL/min) (odds ratio: 0.889; p < 0.001), severe stenosis (odds ratio: 5.218; p = 0.011) or occlusion (odds ratio: 14.697; p = 0.048) of the true lumen in common carotid artery, hypotension on admission (odds ratio: 9.644; p = 0.016), and a longer surgery time (odds ratio: 1.593; p = 0.021). The area under the receiver-operating characteristic curves significantly improved after adding perfusion parameters to clinical and computed tomography angiography characteristics (p = 0.048). This benefit was more pronounced in patients with severe stenosis or occlusion in common carotid artery true lumen (p = 0.004).

CONCLUSIONS: Brain computed tomography perfusion could be a useful prognostic tool for surgically treated acute type A aortic dissection patients and especially beneficial in patients with severe stenosis or occlusion of the common carotid artery true lumen.

PMID:38175783 | DOI:10.1093/ejcts/ezad437

STAR Protoc. 2024 Jan 2;5(1):102806. doi: 10.1016/j.xpro.2023.102806. Online ahead of print.

ABSTRACT

Whole-exome sequencing (WES) is a major approach to uncovering gene-disease associations and pinpointing effector genes. Here, we present a protocol for estimating genetic associations of rare and common variants in large-scale case-control WES studies using MAGICpipeline, an open-access analysis pipeline. We describe steps for assessing gene-based rare-variant association analyses by incorporating multiple variant pathogenic annotations and statistical techniques. We then detail procedures for identifying disease-related modules and hub genes using weighted correlation network analysis, a systems biology approach. For complete details on the use and execution of this protocol, please refer to Su et al. (2023).¹.

PMID:38175747 | DOI:10.1016/j.xpro.2023.102806

Aging (Albany NY). 2024 Jan 3;15. doi: 10.18632/aging.205413. Online ahead of print.

ABSTRACT

Previous studies have indicated a potential connection between plasma levels of Dickkopf-1 (DKK1) and platelet-derived growth factor subunit-B (PDGF-B) with the development of atherosclerosis. However, the causal relationship between DKK1, PDGF-B, and the risk of acute myocardial infarction (AMI) is yet to be established. To address this research gap, we conducted Mendelian randomization (MR) and mediation analyses to investigate the potential mediating role of PDGF-B in the association between DKK1 and AMI risk. Summary statistics for DKK1 (n = 3,301) and PDGF-B (n = 21,758) were obtained from the GWAS meta-analyses conducted by Sun et al. and Folkersen et al., respectively. Data on AMI cases (n = 3,927) and controls (n = 333,272) were retrieved from the UK Biobank study. Our findings revealed that genetic predisposition to DKK1 (odds ratio [OR]: 1.00208; 95% confidence interval [CI]: 1.00056-1.00361; P = 0.0072) and PDGF-B (OR: 1.00358; 95% CI: 1.00136-1.00581; P = 0.0015) was associated with an increased risk of AMI. Additionally, genetic predisposition to DKK1 (OR: 1.38389; 95% CI: 1.07066-1.78875; P = 0.0131) was linked to higher PDGF-B levels. Furthermore, our MR mediation analysis revealed that PDGF-B partially mediated the association between DKK1 and AMI risk, with 55.8% of the effect of genetically predicted DKK1 being mediated through genetically predicted PDGF-B. These findings suggest that genetic predisposition to DKK1 is positively correlated with the risk of AMI, and that PDGF-B partially mediates this association. Therefore, DKK1 and PDGF-B may serve as promising targets for the prevention and treatment of AMI.

PMID:38175715 | DOI:10.18632/aging.205413