Daily Number Of Hospitalizations Research Articles

Novel use of online optimization in a mathematical model of COVID-19 to guide the relaxation of pandemic mitigation measures

Since early 2020, non-pharmaceutical interventions (NPIs)—implemented at varying levels of severity and based on widely-divergent perspectives of risk tolerance—have been the primary means to control SARS-CoV-2 transmission. This paper aims to identify how risk tolerance and vaccination rates impact the rate at which a population can return to pre-pandemic contact behavior. To this end, we developed a novel mathematical model and we used techniques from feedback control to inform data-driven decision-making. We use this model to identify optimal levels of NPIs across geographical regions in order to guarantee that hospitalizations will not exceed given risk tolerance thresholds. Results are shown for the state of Colorado, United States, and they suggest that: coordination in decision-making across regions is essential to maintain the daily number of hospitalizations below the desired limits; increasing risk tolerance can decrease the number of days required to discontinue NPIs, at the cost of an increased number of deaths; and if vaccination uptake is less than 70%, at most levels of risk tolerance, return to pre-pandemic contact behaviors before the early months of 2022 may newly jeopardize the healthcare system. The sooner we can acquire population-level vaccination of greater than 70%, the sooner we can safely return to pre-pandemic behaviors.

Heat, Heatwaves and Cardiorespiratory Hospital Admissions in Helsinki, Finland.

Background: There is a lack of knowledge concerning the effects of ambient heat exposure on morbidity in Northern Europe. Therefore, this study aimed to evaluate the relationships of daily summertime temperature and heatwaves with cardiorespiratory hospital admissions in the Helsinki metropolitan area, Finland. Methods: Time series models adjusted for potential confounders, such as air pollution, were used to investigate the associations of daily temperature and heatwaves with cause-specific cardiorespiratory hospital admissions during summer months of 2001–2017. Daily number of hospitalizations was obtained from the national hospital discharge register and weather information from the Finnish Meteorological Institute. Results: Increased daily temperature was associated with a decreased risk of total respiratory hospital admissions and asthma. Heatwave days were associated with 20.5% (95% CI: 6.9, 35.9) increased risk of pneumonia admissions and during long or intense heatwaves also with total respiratory admissions in the oldest age group (≥75 years). There were also suggestive positive associations between heatwave days and admissions due to myocardial infarction and cerebrovascular diseases. In contrast, risk of arrhythmia admissions decreased 20.8% (95% CI: 8.0, 31.8) during heatwaves. Conclusions: Heatwaves, rather than single hot days, are a health threat affecting morbidity even in a Northern climate.

Heat, heatwaves and cardiorespiratory hospital admissions in Helsinki, Finland

Abstract Background There is a lack of knowledge concerning the effects of heat on morbidity in Northern Europe. Therefore, this study aimed to evaluate the relationships of daily summer-time temperature and heatwaves with cardiorespiratory hospital admissions in Helsinki, Finland. Methods Time-series models adjusted for potential confounders such as air pollution were used to investigate the associations of daily temperature and heatwaves with cause-specific cardiorespiratory hospital admissions, during the summer months of 2000-2017. Daily number of hospitalizations was obtained from the national hospital discharge register, weather information from the Finnish meteorological institute. Results Heatwave-days were associated with an increased risk of pneumonia (RR: 1.17, 95%CI: 1.04-1.31), any respiratory disease in some age groups, and myocardial infarction (RR: 1.54, 95% CI: 1.12-2.12) among person 65-74 years of age. In addition, high effect estimates were observed for many types of cardiorespiratory diseases in association with heatwaves in some age-groups. In contrast, risk of arrhythmia was decreased during heatwaves (RR: 0.81, 95% CI: 0.70-0.93). Conclusions We found no associations and even protective associations between daily mean temperature and cardiorespiratory hospital admissions. However, our results suggest that heatwaves are a serious health threat affecting the morbidity even in the Northern climate Key messages Heatwaves are associated with increased risk of cardio-respiratory hospital admissions. There is a need to adapt to climate change in the public health sector also in Northern Europe to protect vulnerable population groups.

Short term effects of air pollution on hospitalizations for cardiovascular diseases in eight French cities: The PSAS program

Short term associations between air pollution indicators and hospitalizations for cardiovascular diseases have been suggested by epidemiological and clinical studies. The present study aims at estimating the association between particles with diameter <10 microm (PM(10)), nitrogen dioxide (NO(2)) and ozone and hospitalizations for cardiovascular diseases in eight French cities during the 1998-2003 period. The daily number of hospitalizations in each city was extracted from the French hospital information system (PMSI) for cardiovascular diseases, cardiac diseases, ischemic heart diseases and stroke. Excess relative risks (ERRs) of hospitalization associated with a 10 microg/m(3) increase in pollutant levels were estimated in each city by fitting a Poisson regression model, controlling for well-known confounding factors and temporal trends. City-specific results were then combined by inverse variance weighting. Daily number of hospitalizations for cardiovascular diseases was associated with PM(10) levels (for a 10 microg/m(3) increase, ERR=0.8%, 95% CI: [0.2, 1.5]), with NO(2) (1.1%, [0.6, 1.6]) but not with ozone (0.1% [-0.2%, 0.5%]). Associations were stronger in people aged 65 years and over, and when only hospitalizations for ischemic heart diseases were considered. No association was found between strokes and air pollution levels. Our study suggests that the ambient levels of air pollutants currently experienced in the eight French cities, which are close to European air quality guidelines, are yet linked to a short term increase of hospitalizations for cardiovascular diseases. These results are consistent with epidemiological and toxicological data on the cardiovascular effects of air pollution.

Winter air pollution and infant bronchiolitis in Paris

Respiratory syncytial virus (RSV) is one of the most common respiratory pathogens in infants and young children. It is not known why some previously healthy infants, when in contact with RSV, develop bronchiolitis whereas others have only mild symptoms. Our study aimed to evaluate the possible association between emergency hospital visits for bronchiolitis and air pollution in the Paris region during four winter seasons. We included children under the age of 3 years who attended emergency room services for bronchiolitis (following standardized definition) during the period 1997–2001. Two series of data from 34 hospitals, the daily number of emergency hospital consultations ( n=50 857) and the daily number of hospitalizations ( n=16 588) for bronchiolitis, were analyzed using alternative statistical methods; these were the generalized additive model (GAM) and case-crossover models. After adjustments for public holidays, holidays and meteorological variables the case-crossover model showed that PM 10, BS, SO 2 and NO 2 were positively associated with both consultations and hospitalizations. GAM models, adjusting for long-term trend, seasonality, holiday, public holiday, weekday and meteorological variables , gave similar results for SO 2 and PM 10. This study shows that air pollution may act as a trigger for the occurrence of acute severe bronchiolitis cases.