Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study

Background and Objectives: This study aimed to investigate the effective factors in the survival/hazard time of Covid-19 patients in three waves of epidemic.   Methods: All 880 Covid-19 patients were included in this prospective cohort study using the census method. Polymerase chain reaction was use...

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Main Authors: Sadegh Kargarian-Marvasti, Malihe Hasannezhad, Jamile Abolghasemi
Format: Article
Language:fas
Published: Tehran University of Medical Sciences 2021-09-01
Series:مجله اپیدمیولوژی ایران
Subjects:
Online Access:http://irje.tums.ac.ir/article-1-6996-en.html
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author Sadegh Kargarian-Marvasti
Malihe Hasannezhad
Jamile Abolghasemi
author_facet Sadegh Kargarian-Marvasti
Malihe Hasannezhad
Jamile Abolghasemi
author_sort Sadegh Kargarian-Marvasti
collection DOAJ
description Background and Objectives: This study aimed to investigate the effective factors in the survival/hazard time of Covid-19 patients in three waves of epidemic.   Methods: All 880 Covid-19 patients were included in this prospective cohort study using the census method. Polymerase chain reaction was used to diagnose Covid-19. The survival status of these patients was followed up for 4 months. The analysis of this study was based on the time of infection in three epidemic waves in IRAN. To analyze the data, the Kaplan-Meier nonparametric approach and Cox proportional hazards regression model were used. Survival distributions were compared in three epidemic waves using the R software (version 3.6.2) (P<0.05).   Results: We diagnosed 880 positive case of Covid-19 using PCR test on 2269 susspected people who had respiratory symptomps. At the end of 1-year follow-up, cumulative incidence (risk) of Covid-19 was estimated 7%. Effective factors in the survival time of patients with Covid-19 based on Cox multivariate regression model were: 1- Age 2- Intensity of infection (Hospitalization) 3- Heart disease 4- Epidemic Wave and 5- Transmission mode of the disease (P <0.05). The Kaplan-Meier approach and log rank test (Mantel-Cox) showed a significant difference in the survival rate in three epidemic waves (P = 0.018).   Conclusion: Elderly patients, especially those with a history of heart disease, are at higher risk of death than other groups. In addition to regular screening, these patients will need active monitoring, especially at the time of hospitalization.
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spelling doaj.art-338187922dc945fe8192f82c7569f4312022-12-22T04:02:07ZfasTehran University of Medical Sciencesمجله اپیدمیولوژی ایران1735-74892228-75072021-09-01172184193Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort StudySadegh Kargarian-Marvasti0Malihe Hasannezhad1Jamile Abolghasemi2 MSc of Epidemiology, MPH in General Epidemiology, Faculty of Health, Iran University of Medical Sciences, Tehran, Iran; Assistant Professor, MD, Department of Infectious Diseases, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran Associate Professor, Department of Biostatistics, School of Public Health, Iran University of Medical Sciences, Tehran, Iran Background and Objectives: This study aimed to investigate the effective factors in the survival/hazard time of Covid-19 patients in three waves of epidemic.   Methods: All 880 Covid-19 patients were included in this prospective cohort study using the census method. Polymerase chain reaction was used to diagnose Covid-19. The survival status of these patients was followed up for 4 months. The analysis of this study was based on the time of infection in three epidemic waves in IRAN. To analyze the data, the Kaplan-Meier nonparametric approach and Cox proportional hazards regression model were used. Survival distributions were compared in three epidemic waves using the R software (version 3.6.2) (P<0.05).   Results: We diagnosed 880 positive case of Covid-19 using PCR test on 2269 susspected people who had respiratory symptomps. At the end of 1-year follow-up, cumulative incidence (risk) of Covid-19 was estimated 7%. Effective factors in the survival time of patients with Covid-19 based on Cox multivariate regression model were: 1- Age 2- Intensity of infection (Hospitalization) 3- Heart disease 4- Epidemic Wave and 5- Transmission mode of the disease (P <0.05). The Kaplan-Meier approach and log rank test (Mantel-Cox) showed a significant difference in the survival rate in three epidemic waves (P = 0.018).   Conclusion: Elderly patients, especially those with a history of heart disease, are at higher risk of death than other groups. In addition to regular screening, these patients will need active monitoring, especially at the time of hospitalization.http://irje.tums.ac.ir/article-1-6996-en.htmlcovid-19survival analysisepidemiccox proportional hazards modelkaplanmeier nonparametric approach
spellingShingle Sadegh Kargarian-Marvasti
Malihe Hasannezhad
Jamile Abolghasemi
Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study
مجله اپیدمیولوژی ایران
covid-19
survival analysis
epidemic
cox proportional hazards model
kaplanmeier nonparametric approach
title Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study
title_full Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study
title_fullStr Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study
title_full_unstemmed Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study
title_short Effective Factors in the Survival Time of Covid-19 Patients in Three Epidemic Waves: A Prospective Cohort Study
title_sort effective factors in the survival time of covid 19 patients in three epidemic waves a prospective cohort study
topic covid-19
survival analysis
epidemic
cox proportional hazards model
kaplanmeier nonparametric approach
url http://irje.tums.ac.ir/article-1-6996-en.html
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AT jamileabolghasemi effectivefactorsinthesurvivaltimeofcovid19patientsinthreeepidemicwavesaprospectivecohortstudy