Efficacy comparison of different machine learning models to predict adverse inhospital outcome in patients with severe trauma / 中华创伤杂志

Objective:To compare the predictive performance of different machine learning models using pre-hospital data to predict adverse inhospital outcome in patients with severe trauma.Methods:A retrospective cohort study was conducted to analyze the clinical data of 100 135 patients with severe trauma from the National Trauma Data Bank (NTDB) from January 2017 to December 2018. There were 69 644 males and 30 480 females apart from 11 patients with missing gender information, with the range age of 16-89 years [(50.1±21.1)years]. Clinical characteristics included demographic information (sex and age), trauma type (blunt or penetrating trauma), pre-hospital time [emergency medical services (EMS) response time, EMS scene time, and EMS transport time], pre-hospital vital signs (systolic blood pressure, pulse rate, respiratory rate, and oxygen saturation), trauma score [Glasgow coma score (GCS) and injury severity score (ISS)]. The original data were divided into the training set (in the year 2017) and the testing set (in the year 2018) according to the year of admission, including 50 429 patients in the training set and 49 706 patients in the testing set. The patients were classified into non-adverse outcome group ( n=94 526) and adverse outcome group ( n=5 609), according to whether they had an adverse outcome or not. There were 2 808 patients with adverse outcome in the training set and 2 801 patients with adverse outcome in the testing set. All models were built based on the training set. Eight machine learning algorithms consisting of neural network (NNET), naive Bayes (NB), gradient boosting machine (GBM), adaptive boosting (Ada), random forest (RF), bagging tree (BT), categorical boosting (CatBoost) and extreme gradient boosting (XGB) were used to construct prediction models for clinical outcomes among patients with severe trauma based on their clinical features. Models were evaluated according to the sensitivity, specificity, area under the receiver operating characteristic (ROC) curve (AUC) and Hosmer-Lemeshow goodness-of-fit test. Results:Of the NNET, NB, GBM, Ada, RF, BT, CatBoost and XGB models in the testing set, the sensitivity was 0.84, 0.83, 0.27, 0.79, 0.83, 0.81, 0.62 and 0.78, respectively; the specificity was 0.79, 0.76, 0.81, 0.79, 0.79, 0.74, 0.83 and 0.79, respectively; the AUC was 0.89 (95% CI 0.88, 0.90), 0.86 (95% CI 0.85, 0.87), 0.54 (95% CI 0.53, 0.55), 0.86 (95% CI 0.85, 0.87), 0.88 (95% CI 0.88, 0.90), 0.83 (95% CI 0.82, 0.85), 0.77 (95% CI 0.76, 0.79) and 0.86 (95% CI 0.85, 0.87), respectively. The NNET model had the best differentiation. In terms of calibration degree, both NNET and NB showed good performance ( P>0.05 for Hosmer-Lemeshow goodness-of-fit test). Conclusion:The NNET model has a favorable predictive performance for adverse inhospital outcome in patients with severe trauma, which may provide a reference for the rapid prediction of prognosis in patients with severe trauma.

Calcium channel blockers improve prognosis of patients with coronavirus disease 2019 and hypertension / 中华医学杂志(英文版)

BACKGROUND@#Hypertension is considered an important risk factor for the coronavirus disease 2019 (COVID-19). The commonly anti-hypertensive drugs are the renin-angiotensin-aldosterone system (RAAS) inhibitors, calcium channel blockers (CCBs), and beta-blockers. The association between commonly used anti-hypertensive medications and the clinical outcome of COVID-19 patients with hypertension has not been well studied.@*METHODS@#We conducted a retrospective cohort study that included all patients admitted with COVID-19 to Huo Shen Shan Hospital and Guanggu District of the Maternal and Child Health Hospital of Hubei Province, Wuhan, China. Clinical and laboratory characteristics were extracted from electronic medical records. Hypertension and anti-hypertensive treatment were confirmed by medical history and clinical records. The primary clinical endpoint was all-cause mortality. Secondary endpoints included the rates of patients in common wards transferred to the intensive care unit and hospital stay duration. Logistic regression was used to explore the risk factors associated with mortality and prognosis. Propensity score matching was used to balance the confounders between different anti-hypertensive treatments. Kaplan-Meier curves were used to compare the cumulative recovery rate. Log-rank tests were performed to test for differences in Kaplan-Meier curves between different groups.@*RESULTS@#Among 4569 hospitalized patients with COVID-19, 31.7% (1449/4569) had a history of hypertension. There were significant differences in mortality rates between hypertensive patients with CCBs (7/359) and those without (21/359) (1.95% vs. 5.85%, risk ratio [RR]: 0.32, 95% confidence interval [CI]: 0.13-0.76, χ2 = 7.61, P = 0.0058). After matching for confounders, the mortality rates were similar between the RAAS inhibitor (4/236) and non-RAAS inhibitor (9/236) cohorts (1.69% vs. 3.81%, RR: 0.43, 95% CI: 0.13-1.43, χ2 = 1.98, P = 0.1596). Hypertensive patients with beta-blockers (13/340) showed no statistical difference in mortality compared with those without (11/340) (3.82% vs. 3.24%, RR: 1.19, 95% CI: 0.53-2.69, χ2 = 0.17, P = 0.6777).@*CONCLUSIONS@#In our study, we did not find any positive or negative effects of RAAS inhibitors or beta-blockers in COVID-19 patients with hypertension, while CCBs could improve prognosis.

Association between cough and tobacco smoking exposure among construction workers / 中国职业医学

OBJECTIVE: To study the effects of tobacco smoking exposure on cough among construction workers. METHODS: Convenient sampling method was adopted to choose 204 construction workers as the study objects. The relationship of cough and tobacco smoking exposure was investigated. The objects were divided into no-smoking( 18 workers),passive-smoking( 66 workers) and active-smoking( 120 workers) groups according to different tobacco smoking exposure situation. RESULTS: The occurrence of active smoking for 204 construction workers was 58. 8%( 120 /204) and the daily active smoking rate was 51. 5%( 105 /204). The occurrence of passive smoking for the non-smokers was 78. 6%( 66 /84) and the daily passive smoking rate was 66. 7%( 56 /84). Among the construction workers,15. 2%( 31 /204) had occasional cough,and 52. 4%( 107 /204) had frequent cough,total cough occurrence was 67. 6%( 138 /204). The occurrence of occasional cough in active-smoking group was higher than that of the passive-smoking group( 23. 3% vs 1. 5%,P < 0. 01); the occurrence of frequent cough in passive-smoking group and active-smoking group were higher than that of the no-smoking group( 54. 5% vs 22. 2%,55. 8% vs 22. 2%,P < 0. 017); the total cough occurrence in active-smoking group was higher than those of the no-smoking group and passive-smoking group( 79. 2% vs 33. 3%,79. 2% vs 56. 1%,P < 0. 01). There was an association between tobacco smoking exposure and cough frequency among the construction workers. Active-smokers had higher risks than non-smokers in both occasional cough and frequent cough( odds ratio were 5. 958 and 6. 990,P <0. 05); the passive smokers had a higher risk of frequent cough than non-smokers( odds ratio was 3. 536,P < 0. 05).CONCLUSION: Tobacco smoking exposure was an important risk factor for coughing among construction workers. Effective approach should be taken into account to control tobacco usage in the construction work site.

Research on the features of DNA damage in nasopharyngeal carcinoma patients of normal constitution and abnormal constitution and in high-risk population of nasopharyngeal carcinoma / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the features of DNA damage in nasopharyngeal carcinoma (NPC) patients of normal constitution and abnormal constitution and in high-risk population of NPC.</p><p><b>METHODS</b>Using single cell gel electrophoresis technique, the DNA damage of peripheral blood lymphocytes was detected in 28 healthy subjects, 27 in high-risk population of NPC, and 13 NPC patients at their first visits. The DNA damage was detected in the populations of normal constitution and of abnormal constitution. The tail length, the tail moment, and the tail DNA% were taken as the indices of DNA damage.</p><p><b>RESULTS</b>The tail length was (35.77 +/- 4.22) microm, the tail moment was (8.10 +/- 1.63) microm, and the tail DNA% was 57.48% +/- 4.63% in NPC patients. They were (15.25 +/- 4.15) microm, (5.01 +/- 1.92) microm, and 31.99% +/- 4. 11% in high-risk population of NPC. They were (14.31 +/- 3.64) microm, (4. 37 +/- 1.80) microm, and 29. 89% +/- 3. 15% in healthy subjects. There was statistical difference in the three indices among the three populations (P <0.05). In all the three populations, more DNA damage existed in those of abnormal constitution than in those of normal constitution (P <0.05).</p><p><b>CONCLUSIONS</b>Obvious instability of genetic materials exists in NPC patients, manifested as severe DNA damage of lymphocytes. In all the three populations, more DNA damage existed in those of abnormal constitution than in those of normal constitution.</p>

Cluster analysis applied in the epidemiological stratification analysis / 中华流行病学杂志

<p><b>OBJECTIVE</b>To establish a new method on stratification analysis when the stratification limits of confounding factors was not clear or contradictory.</p><p><b>METHOD</b>Data on a study of diabetes mellitus in Guangdong province collected in the year of 1997 and 1998 was analyzed using cluster-stratification analysis.</p><p><b>RESULTS</b>The efficiency of stratification analysis was improved and the confounding bias was effectively controlled with information bias avoided when the clusters-stratification analysis was applied.</p><p><b>CONCLUSION</b>The problem was logically solved using cluster analysis as an assistant stratification means.</p>