Prolonged capillary refill time and short-term mortality of critically ill patients: A meta-analysis.

BACKGROUND: Prolonged capillary refill time (CRT) is an indicator of poor peripheral perfusion. The aim of the systematic review and meta-analysis was to evaluate the association of prolonged CRT and mortality of critically ill patients. METHODS: To achieve the objective of this meta-analysis, we conducted a thorough search of PubMed, Embase, Cochrane Library, and the Web of Science to identify relevant observational studies with longitudinal follow-up. The Cochrane Q test was utilized to assess between-study heterogeneity, and the I2 statistic was calculated to estimate the degree of heterogeneity. We employed random-effects models to combine the outcomes, considering the potential influence of heterogeneity. RESULTS: Eleven studies, encompassing 11,659 critically ill patients were included. During follow-up durations within hospitalization to 3 months, 1247 (10.7%) patients died. The pooled results indicated that a prolonged CRT at early phase of admission was significantly associated with an increased risk of all-cause mortality (risk ratio [RR]: 1.73, 95% confidence interval [CI]: 1.39 to 2.16, p < 0.001; I2 = 60%). Subgroup analyses showed that the association was not significantly modified by study design (prospective or retrospective), etiology of diseases (infection, non-infection, or mixed), or cutoff of CRT (>3 s, 3.5 s, or 4 s). The association between CRT and mortality was weaker in studies with multivariate analysis (RR: 1.43, 95% CI: 1.27 to 1.60, p < 0.001; I2 = 0%) as compared to that derived from studies of univariate analysis (RR: 6.27, 95% CI: 3.29 to 11.97, p < 0.001; I2 = 0%). CONCLUSIONS: Prolonged CRT at admission may be a predictor of increased short-term mortality of critically ill patients.

Impact of the COVID-19 pandemic on the operations of the specialty hospital department in Beijing.

The coronavirus disease 2019 (COVID-19) pandemic was disruptive to non-COVID-19-related healthcare. This study aimed to compare patient inflows and patient population characteristics at the Hand Surgery Department of JiShuiTan (JST) Hospital in Beijing, a top referral center, in 2020 during the pandemic relative to the same period in 2019. This cross-sectional study was conducted to analyze the impact of the COVID-19 pandemic on patients admitted to the hand surgery ward. The participants were patients admitted from January to April 2019 (J-A19) and from January to April 2020 (J-A20). The medical records were analyzed, including age, sex, admission time, admission mode, admission diagnosis, and patient residence. Significantly fewer patients were admitted in J-A20 than in J-A19, with particularly dramatic reductions observed for non-Beijing residents and nonemergency cases (e.g., congenital anomalies operations for children). The top 5 diagnosis types for admitted patients were consistent throughout J-A19 and in January 2020. The rank of the diagnostic type "open injuries of the hand and wrist" increased significantly in February, March, and April of 2020 compared with 2019. The COVID-19 pandemic decreased patient admissions, especially for nonemergency patients, during J-A20.

A 600 mg of fixed-dose linezolid in renally impaired patients versus 15 mg/kg intermittent dose-optimized vancomycin in renally non-impaired patients: A single centre retrospective analysis for adult patients with hospital-acquired pneumonia due to methicillin-resistant Staphylococcus aureus.

OBJECTIVES: Both linezolid and vancomycin are approved by USFDA and IDSA guidelines for the management of nosocomial pneumonia due to methicillin-resistant Staphylococcus aureus (MRSA) in clinical practice. Baseline creatinine clearance is the criterion for prescribing vancomycin or linezolid for hospital-acquired pneumonia in our institution. However, patients with renal function impairment are far more difficult to manage in intensive care. Thus, the objectives of the study were to compare the clinical efficacy and safety of 600 mg of fixed-dose linezolid with intermittent dose-optimised vancomycin in hospital-acquired pneumonia due to MRSA and to evaluate parameters of clinical cure. METHODS: Analysis of a review of patients' charts. Patients with creatinine clearance <80 ml/min received 600 mg linezolid/12 h (n = 139, LN cohort), and patients with creatinine clearance ≥80 ml/min received intravenous 15 mg/kg vancomycin/12 h for 1-2 weeks consecutively or 3 weeks in case of bacteremia (n = 152, VC cohort) for management of hospital-acquired pneumonia due to MRSA. RESULTS: A 59% of patients from the LN cohort and 47% of patients from the VC cohort were clinically cured. Administration of systemic steroids (p = 0.0412) and ≥ 80 ml/min creatinine clearance (p = 0.0498) were the independent parameters for the clinical cure of patients. Nephrotoxicity was higher among patients of the VC cohort than the LN cohort (p = 0.0464). Treatment failed in 41% of patients from the LN cohort and in 53% of patients from the VC cohort (p = 0.0200). CONCLUSIONS: A 600 mg of fixed-dose linezolid is an ideal alternative to intermittent dose-optimised vancomycin for better clinical outcomes for patients with hospital-acquired pneumonia due to MRSA, especially for patients with renal impairment.

Prior Guided Transformer for Accurate Radiology Reports Generation.

In this paper, we propose a prior guided transformer for accurate radiology reports generation. In the encoder part, a radiograph is firstly represented by a set of patch features, which is obtained through a convolutional neural network and a traditional transformer encoder. Then an Additive Gaussian model is applied to represent the prior knowledge based on unsupervised clustering and sparse attention. In the decoder part, prior embeddings are acquired by probabilistically sampling from the radiograph prior. Then the visual features, language embeddings, and prior embeddings are fused by our proposed Prior Guided Attention to generate accurate radiology reports. Experiment results show that our method achieves better performance than state-of-the-art methods on two public radiology datasets, which proves the effectiveness of our prior guided transformer.

Effect of different resumption strategies to flatten the potential COVID-19 outbreaks amid society reopens: a modeling study in China.

BACKGROUND: The effect of the COVID-19 outbreak has led policymakers around the world to attempt transmission control. However, lockdown and shutdown interventions have caused new social problems and designating policy resumption for infection control when reopening society remains a crucial issue. We investigated the effects of different resumption strategies on COVID-19 transmission using a modeling study setting. METHODS: We employed a susceptible-exposed-infectious-removed model to simulate COVID-19 outbreaks under five reopening strategies based on China's business resumption progress. The effect of each strategy was evaluated using the peak values of the epidemic curves vis-à-vis confirmed active cases and cumulative cases. Two-sample t-test was performed in order to affirm that the pick values in different scenarios are different. RESULTS: We found that a hierarchy-based reopen strategy performed best when current epidemic prevention measures were maintained save for lockdown, reducing the peak number of active cases and cumulative cases by 50 and 44%, respectively. However, the modeled effect of each strategy decreased when the current intervention was lifted somewhat. Additional attention should be given to regions with significant numbers of migrants, as the potential risk of COVID-19 outbreaks amid society reopening is intrinsically high. CONCLUSIONS: Business resumption strategies have the potential to eliminate COVID-19 outbreaks amid society reopening without special control measures. The proposed resumption strategies focused mainly on decreasing the number of imported exposure cases, guaranteeing medical support for epidemic control, or decreasing active cases.

Risk assessment of the step-by-step return-to-work policy in Beijing following the COVID-19 epidemic peak.

Novel coronavirus (COVID-19) is a new strain of coronavirus first identified in Wuhan, China. As the virus spread worldwide causing a global pandemic, China reduced transmission at considerable social and economic cost. Post-lockdown, resuming work safely, that is, while avoiding a second epidemic outbreak, is a major challenge. Exacerbating this challenge, Beijing hosts many residents and workers with origins elsewhere, making it a relatively high-risk region in which to resume work. Nevertheless, the step-by-step approach taken by Beijing appears to have been effective so far. To learn from the epidemic progression and return-to-work measures undertaken in Beijing, and to inform efforts to avoid a second outbreak of COVID-19, we simulated the epidemiological progression of COVID-19 in Beijing under the real scenario of multiple stages of resuming work. A new epidemic transmission model was developed from a modified SEIR model for SARS, tailored to the situation of Beijing and fitted using multi-source data. Because of strong spatial heterogeneity amongst the population, socio-economic factors and medical capacity of Beijing, the risk assessment was undertaken spatiotemporally with respect to each district of Beijing. The epidemic simulation confirmed that the policy of resuming work step-by step, as implemented in Beijing, was sufficient to avoid a recurrence of the epidemic. Moreover, because of the structure of the model, the simulation provided insights into the specific factors at play at different stages of resuming work, allowing district-specific recommendations to be made with respect to monitoring at different stages of resuming work . As such, this research provides important lessons for other cities and regions dealing with outbreaks of COVID-19 and implementing return-to-work policies.

Clinical features of rabies patients with abnormal sexual behaviors as the presenting manifestations: a case report and literature review.

BACKGROUND: Abnormal sexual behaviors presenting as manifestations of rabies have occasionally been reported in the literature, although little attention has been paid to these cases to date. This study aimed to analyze the clinical features of rabies cases with abnormal sexual behaviors as the presenting manifestations. CASE PRESENTATION: A case of 32-year-old man with frequent ejaculation as the initial symptom of rabies was first reported. Then, a literature review was conducted using databases including CNKI, SinoMed, VIP, Wanfang Data, ScienceDirect, ProQuest, OVID and PubMed. In addition to our case, 54 other rabies cases, with abnormal sexual behaviors as the presenting manifestations, have been reported since 1970. Among the 55 cases, 51 were male and three were female (unknown gender for one case), with ages ranging from 6 to 71 years. All cases were reported in developing countries, 46 in China. Dog bites were the major source of infection, and extremities were the main exposure sites. Overall, 46 (83.6%) cases had abnormal sexual behaviors as the initial symptoms. The major presenting manifestations were priapism and ejaculation in males and hypersexuality in females. All cases were clinically diagnosed based on medical history and clinical manifestations. Given no standardized post-exposure prophylaxis, all cases died with the survival time being between 1 and 15 days. CONCLUSIONS: The rabies patients with abnormal sexual behaviors have unique clinical features. To avoid misdiagnosis, unexplained abnormal sexual behaviors should raise clinical suspicion of rabies.

Recent advances in mechanism-based chemotherapy drug-siRNA pairs in co-delivery systems for cancer: A review.

Co-delivery of chemotherapy drugs and siRNA for cancer therapy has achieved remarkable results according to synergistic/combined antitumor effects, and is recognized as a promising therapeutic modality. However, little attention has been paid to the extremely complex mechanisms of chemotherapy drug-siRNA pairs during co-delivery process. Proper selection of chemotherapy drug-siRNA pairs is beneficial for achieving desirable cancer therapeutic effects. Exploring the inherent principles during chemotherapy drug-siRNA pair selection for co-delivery would greatly enhanced therapeutic efficiency. To achieve ideal results, this article will systematically review current different mechanism-based chemotherapy drug-siRNA pairs for co-delivery in cancer treatment. Large-scale library screening of recent different chemotherapy drug-siRNA pairs for co-delivery would help to establish the chemotherapy drug-siRNA pair selection principle, which could pave the way for co-delivery of chemotherapy drugs and siRNA for cancer treatment in clinic. Following the inherent principle of chemotherapy drug-siRNA pair, more effective co-delivery vectors can be designed in the future.

[Study on the effect of the haze episodes on the visits to pediatrics outpatient departments and emergency departments in Beijing].

OBJECTIVE: The aim of this study was to investigate the impact of air pollution on the number of pediatric outpatient and emergency room visits in January 2013. METHODS: Health-related data was from a major hospital in Haidian,Beijing while related data on air pollution was from the Chinese Research Academy of Environmental Sciences. Data on weather was from the China Weather Website. Number of hospital outpatient visits per day during the haze period was compared to those from the previous year to get the increase of percentage. Concentration-response functions were estimated using generalized additive modeling with natural log link function, while multiple structural change test was used to determine the changing point in CRFs. Constrained piecewise linear function was used to estimate the risks for different segments of CRFs. RESULTS: The peak of NO(X), SO2, PM(2.5) and PM(10) reached 672.63 µ g/m³, 146.20 µ g/m³, 312.19 µ g/m³ and 995.00 µ g/m³, around 28 December 2012 and 10 January 2013. The peaks of visits to the pediatric department were observed at the some days, showing 47.75% and 34.14% of increase in the visits to the pediatric department. In the low or intermediate ranges of concentration, all the four air pollutants were significantly associated with pediatric outpatient visits, in the form of C- and S- shape of concentration-response function. However, in the range of high concentration, only PM(10) and SO2were significantly associated with the number of visits to the pediatric emergency room, appeared as the J-shape form. Discernable thresholds were found in S- and J- shapes which were located at 200 µg/m³, 20 µg/m³, 40 µg/m³ and 100 µ g/m³ for NO(X), SO2, PM(2.5) and PM(10), respectively. CONCLUSION: Air pollution during the haze period was associated with the increase of pediatric outpatient and emergency room visits. There were different sensitive groups within the pediatric cases. Their susceptibility showed a decreasing trend from C-, S-, to J- shape related group.

[Changes in blood lymphocytes in sepsis patients].

OBJECTIVE: To investigate the change in blood lymphocyte levels and lymphocyte percentage in critical patients, including those with non-infectious systemic inflammatory response syndrome (SIRS), sepsis and severe sepsis. METHODS: Clinical data of 423 patients admitted to intensive care unit (ICU) of Department of Emergency of Peking University Third Hospital from January 2011 to September 2013 were retrospectively analyzed. Among these patients, there were 54 with non-infectious SIRS, 177 with sepsis and 192 with severe sepsis. 150 of them died, and 273 survived. The white blood count (WBC), neutrophil (N), lymphocyte count, lymphocyte percentage, lactic acid,serum high-sensitivity C-reactive protein (hs-CRP) and procalcitonin (PCT) were determined at admission, and acute physiology and chronic health evaluation II (APACHE II) was estimated. The patients were divided into different groups according to diagnosis and prognosis to compare the value of the indexes, and the correlation between lymphocyte count and other markers were analyzed by Spearman relative analysis. RESULTS: The older the patients, the more severe the disease. In the non-infective SIRS, sepsis and severe sepsis groups, APACHE II scores (7.78 ± 3.72, 13.85 ± 7.22,24.00 ± 9.79), time of stay in hospital (days: 6.0 (1.0, 9.0), 12.0 (8.0, 22.0), 19.5 (7.0, 29.0)], the mortality rate (0, 10.2%, 52.6%), WBC ( x 109/L: 7.59 ± 3.27, 8.94 ± 3.95, 10.32 ± 5.50), N (0.685 ± 0.132, 0.778 ± 0.135,0.831 ±0.086), hs-CRP (mg/L: 4.60 (2.80, 7.52), 23.58 (13.49, 49.22), 59.77 (19.36, 110.62)] and PCT[j.Lg/L: 0.05 (0.05, 0.05), 0.09 (0.05, 0.61), 0.63 (0.10, 5.25)] showed gradually increasing tendency (all P=0.000). Serum lymphocyte count levels (X 109/L: 1.53 (0.89, 1.88), 0.90 (0.65, 1.42) and 0.80 (0.50, 1.12)], lymphocyte percentage (0.225 ± 0.122, 0.138 ± 0.097, 0.106 ± 0.070) showed gradually decreasing tendency (P<0.05 or P<0.01). There was significant difference in blood lactic acid among three groups [blood lactic acid were 2.40 ( 1.30, 5.10),1.10 (0.80, 2.00) and 1.40 (1.00, 2.50) mmol/L in the non-infective SIRS, sepsis and severe sepsis groups, respectively, P=0.000). Age (years old: 76.71 ± 12.21 vs. 73.21 ± 14.49), APACHE ll score (24.69 ± 9.58 vs. 13.91 ± 8.41),time of stay in hospital [days: 12.0 (4.0, 28.0) vs. 11.0 (8.0, 22.0) J, WBC (X 109/L: 10.29 ± 5.82 vs. 8.89 ± 3.98), N (0.809 ± 0.130 vs. 0. 776 ± 0.120), lactic acid [mmol/L: 1.80 (1.10, 2.90) vs. 1.30 (0.90, 2.49) J, hs-CRP [mg/L:50.94 (19.21, 97.13) vs. 21.71 (6.39, 54.40)] and PCT [J.Lg/L: 0.74 (0.13, 5.83) vs. 0.08 (0.05, 0.59)] levels in the death group were higher than those in the survival group (P<0.05 or P<0.01), serum lymphocyte count levels [X 109/L: 0.90 (0.50, 1.29) vs. 1.05 (0.70, 1.54)], lymphocyte percentage (0.123 ±0.098 vs. 0.143 ±0.097) level in the death group were obviously lower than those in the survival group (P<0.01 and P<0.05). Serum lymphocyte count levels were negative correlated with N (r= -0.597, P=0.000), hs-CRP (r= -0.298, P=0.000), PCT (r=-0.304, P=0.000), APACHE ll (r=-0.124, P=0.000), and positively correlated with lymphocyte percentage (r=0.691, P=0.000), and non correlations was found with WBC (r=0.082, P=0.091) and lactic acid (r=0.073, P=0.132). CONCLUSION: The serum lymphocyte levels in the critically ill patients are related with the severity of sepsis, and monitoring the change in lymphocyte may be an indicator for evaluating the illness and effect of treatment.

The burden of air pollution on years of life lost in Beijing, China, 2004-08: retrospective regression analysis of daily deaths.

OBJECTIVES: To better understand the burden of air pollution on deaths, we examined the effects of air pollutants on years of life lost (YLL) in Beijing, China. DESIGN: Retrospective regression analysis using daily time series. SETTING: 8 urban districts in Beijing, China. PARTICIPANTS: 80 515 deaths (48 802 male, 31 713 female) recorded by the Beijing death classification system during 2004-08. MAIN OUTCOME MEASURES: Associations between daily YLL and ambient air pollutants (particulate matter with aerodynamic diameter <2.5 µm (PM2.5), PM10, SO2, and NO2), after adjusting for long term trends, seasonality, day of the week, and weather conditions. We also examined mortality risk related to air pollutants. RESULTS: Mean concentrations of daily PM2.5, PM10, SO2 and NO2 were 105.1 µg/m(3), 144.6 µg/m(3), 48.6 µg/m(3), and 64.2 µg/m(3), respectively. All air pollutants had significant effects on years of life lost when we used single pollutant models. An interquartile range (IQR) increase in PM2.5, PM10, SO2, and NO2 was related to YLL increases of 15.8, 15.8, 16.2, and 15.1 years, respectively. The effects of air pollutants on YLL appeared acutely and lasted for two days (lag 0-1); these effects associated with an IQR increase in PM2.5 were greater in women than men (11.1 (95% confidence interval 4.7 to 17.5) v 4.7 (-2.9 to 12.3) YLL) and in people aged up to 65 years than those older than 65 years (12.0 (2.9 to 21) v 3.8 (-0.9 to 8.6) YLL). The mortality risk associated with an IQR increase in PM2.5 was greater for people older than 65 years (2.5% (95% confidence interval 0.6% to 4.5%) increase of mortality) than those aged up to 65 years (0.7% (-0.8% to 2.2%)). CONCLUSIONS: YLL provides a complementary measure for examining the effect of air pollutants on mortality. Increased YLL are associated with increased air pollution. This study highlights the need to reduce air pollution in Beijing, China, to protect the health of the population.

The characteristic of heat wave effects on coronary heart disease mortality in Beijing, China: a time series study.

BACKGROUND: There is limited evidence for the impacts of heat waves on coronary heart disease (CHD) mortality in Beijing, capital city of China. OBJECTIVES: We aimed to find a best heat wave definition for CHD mortality; and explore the characteristic of heat wave effects on CHD in Beijing, China. METHODS: We obtained daily data on weather and CHD mortality in Beijing for years 2000-2011. A quasi-Poisson regression model was used to assess the short-term impact of heat waves on CHD mortality in hot season (May-September), while controlling for relative humidity, day of the week, long-term trend and season. We compared 18 heat wave definitions by combining heat wave thresholds (87.5(th), 90.0(th), 92.5(th), 95(th), 97.5(th), and 99(th) percentile of daily mean temperature) with different duration days (≥ 2 to ≥ 4 days), using Akaike information criterion for quasi-Poisson. We examined whether heat wave effects on CHD mortality were modified by heat wave duration and timing. RESULTS: Heat wave definition using 97.5(th) percentile of daily mean temperature (30.5 °C) and duration ≥ 2 days produced the best model fit. Based on this heat wave definition, we found that men and elderly were sensitive to the first heat waves of the season, while women and young were sensitive to the second heat waves. In general, the longer duration of heat waves increased the risks of CHD mortality more than shorter duration for elderly. The first two days of heat waves had the highest impact on CHD mortality. Women and elderly were at higher risks than men and young when exposed to heat waves, but the effect differences were not statistically significant. CONCLUSIONS: Heat waves had significant impact on CHD mortality. This finding may have implications for policy making towards protecting human health from heat waves.

Common underlying diseases do not contribute in determining the causes of sudden unexplained death.

BACKGROUND: Underlying diseases have a statistically significant positive correlation to sudden death. However, sudden unexplained death (SUD) is different from sudden death, as there is no clinical evidence to support the sudden death due to the original underlying disease, nor a lethal pathological basis to be found during autopsy. In addition, SUD are more common in young, previously healthy individuals, usually without any signs of disease, with no positive lesions found after autopsy. Therefore, a causal relationship between SUD and the underlying disease needs to be further explored. This study aimed to explore the role that common underlying diseases play in patients with SUD and to reveal the correlation between them. METHODS: The medical records, history and case information of 208 patients with SUD were collected for the survey. All these SUD occurred in the emergency room of Peking University Third Hospital from January 2006 to December 2009. The patients were stratified by with and without common underlying diseases. To examine possible associations between the underlying diseases and the cause of unexplained sudden death, the chi-squared and Fisher's exact tests were used. RESULTS: Among the 208 patients, 65 were diagnosed with common underlying diseases while 143 were not. Within these two groups, there were 45 patients for whom the clear cause of death was determined. However, there were no statistically significant differences or strong associations (χ(2) = 1.238, P > 0.05) between the 11 patients with (16.90%) and 34 without (23.78%) common underlying disease among these 45 patients. We also found that occurrence of the common underlying diseases, such as neurological system, cardiovascular and pulmonary system diseases, are not statistically significant (P > 0.05) in the diagnosis of the SUD. CONCLUSION: Common underlying diseases make no obvious contributions to SUD and are not useful in diagnosing the underlying reasons for death.

Time-series analysis of the relationship between air quality, temperature, and sudden unexplained death in Beijing during 2005 - 2008.

BACKGROUND: There is a yearly increase in the rate of sudden unexplained death (SUD), even through extensive physical examination and the testing of a large number of biomarkers, the cause of sudden death in patients previously in good health cannot be fully determined. During clinical practice, a spatial aggregation phenomenon has been observed in the incidence of sudden unexplained death. Previous research has shown that environmental factors, such as air pollution, weather conditions, etc., have a significant impact on human health. In the wake of the continuous environmental damage, the relationship between environmental factors and sudden unexplained death still needs to be studied. To study the relationship between sudden unexplained death and air quality and temperature, commonly used markers such as particulate matter of aerodynamic diameter < 10 µm (PM(10)), daily average concentration of the gaseous pollutants sulfur dioxide (SO2) and nitrogen dioxide (NO2), and the daily average temperature were investigated. METHODS: The methods include collecting the data of sudden unexplained death; air quality monitoring; meteorological monitoring from January 1, 2005 to December 31, 2008; utilizing generalized additive models (GAM); controlling the influential factors such as secular trend, seasonal trend, and Sunday dummy variable; and analyzing the correlation between daily inhalable particle concentration, daily average temperature, and the number of daily SUD. RESULTS: There was no statistical significance between the daily inhalable particle and daily incidence of sudden unexplained death. Incidence rate of sudden unexplained death had nonlinear positive correlation with daily temperature. When the temperature was 5°C above the daily average temperature, the daily incidence of sudden unexplained death went up with the rising temperature. CONCLUSION: Temperature may be one of the key risk factor or precipitating factor of SUD.

Analysis of the prodromal symptoms of unexplained sudden death in patients with or without underlying diseases.

BACKGROUND: In recent years, the incidence of unexplained sudden death has risen significantly across the world. However, it occurred suddenly, often in young apparently healthy individuals and almost 50% of the patients did not have any warning signals or symptoms. Therefore, the prodromal symptoms before the incident are extremely important for early prediction of sudden death. In this article, we aimed to explore the value of prodromal symptoms for unexplained sudden death and whether the prodromal symptoms have a predictive function to unexplained sudden death (USD) without underlying diseases. METHODS: A total of 208 sudden death cases were selected for the survey in the Emergency Department of Peking University Third Hospital from January 2006 to December 2009 and their medical records were reviewed. The patients were divided into two groups, 65 patients had underlying diseases while 143 had not underlying diseases. In the meantime, their prodromal symptoms were collected and compared, prodromal symptoms including chest distress, dyspnea, syncope, fever, headache, vomiting, etc. RESULTS: Patients with underlying diseases were compared to those without underlying diseases associated with sudden death; there was no significant difference in gender and age distribution. Among the 208 cases, 39 cases (18.75%) had prodromal symptoms, patients with underlying diseases had prodromal symptoms in 12 cases (18.46%), while patients without underlying diseases had prodromal symptoms in 27 cases (18.88%). The difference between the two groups with prodromal symptoms was not statistically significant (P > 0.05). CONCLUSIONS: Prodromal symptoms are extremely important warning signals in the occurrence of USD. It has equally important predictive value for patients both with and without underlying diseases, especially in predicting sudden death caused by cardiopulmonary and neurological diseases.

Ambient temperature and coronary heart disease mortality in Beijing, China: a time series study.

BACKGROUND: Many studies have examined the association between ambient temperature and mortality. However, less evidence is available on the temperature effects on coronary heart disease (CHD) mortality, especially in China. In this study, we examined the relationship between ambient temperature and CHD mortality in Beijing, China during 2000 to 2011. In addition, we compared time series and time-stratified case-crossover models for the non-linear effects of temperature. METHODS: We examined the effects of temperature on CHD mortality using both time series and time-stratified case-crossover models. We also assessed the effects of temperature on CHD mortality by subgroups: gender (female and male) and age (age > =65 and age < 65). We used a distributed lag non-linear model to examine the non-linear effects of temperature on CHD mortality up to 15 lag days. We used Akaike information criterion to assess the model fit for the two designs. RESULTS: The time series models had a better model fit than time-stratified case-crossover models. Both designs showed that the relationships between temperature and group-specific CHD mortality were non-linear. Extreme cold and hot temperatures significantly increased the risk of CHD mortality. Hot effects were acute and short-term, while cold effects were delayed by two days and lasted for five days. The old people and women were more sensitive to extreme cold and hot temperatures than young and men. CONCLUSIONS: This study suggests that time series models performed better than time-stratified case-crossover models according to the model fit, even though they produced similar non-linear effects of temperature on CHD mortality. In addition, our findings indicate that extreme cold and hot temperatures increase the risk of CHD mortality in Beijing, China, particularly for women and old people.