Statistical Evaluation of Comorbidities and Environmental Factors in COVID-19 Outcomes: Risk Measures and Predictive Analysis Using Odds and Hazard Ratios

Authors

  • Mohd Rashid Khan International Institute for Population Sciences, Mumbai-400088, Maharashtra, India
  • Faizan Danish Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology-Andhra Pradesh (VIT- AP) University, Inavolu, Beside AP Secretariat, Amaravati AP-522237, India
  • Mustafa Ibrahim Ahmed Araibi Department of Business Administration, College of Business, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11432, Saudi Arabia
  • I. Elbatal Department of Mathematics and Statistics, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11432, Saudi Arabia
  • Ehab M. Almetwally Department of Mathematics and Statistics, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11432, Saudi Arabia
  • Ahmed M. Gemeay Department of Mathematics, Faculty of Science, Tanta University, Tanta 31527, Egypt
  • G.R.V. Triveni Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology-Andhra Pradesh (VIT- AP) University, Inavolu, Beside AP Secretariat, Amaravati AP-522237, India
  • Rafia Jan Department of Statistics, Govt. Degree College Bejbehara, Anantnag-192124, J&K, India
  • V.R.K. Reddy Department of Mathematics, School of Advanced Sciences, Vellore Institute of Technology-Andhra Pradesh (VIT- AP) University, Inavolu, Beside AP Secretariat, Amaravati AP-522237, India
  • Aafaq A. Rather Symbiosis Statistical Institute, Symbiosis International (Deemed University), Pune, India

DOI:

https://doi.org/10.6000/1929-6029.2025.14.40

Keywords:

COVID-19, Hazard Ratio, Odds Ratio, Comorbidity, Predictive Analysis

Abstract

In this study, we have reviewed studies that highlight the effects of common conditions like heart disease, high blood pressure, congestive heart failure, kidney problems, and emphysema, which offer the largest risk of death caused by COVID-19. Also, explored how physical activity can influence one's resistance to COVID-19, the effects of stat in medications on mortality rates, and the effectiveness of vaccines in reducing fatalities offer valuable avenues for tailored interventions and treatment strategies and the examination of the relationship between exposure to air contamination and the severity of COVID-19 highlights the task of environmental factors in shaping the outcomes of the illness. Primarily, we focused on how comorbidities affect COVID-19 patients and the associations between comorbidities, lifestyle factors, environmental influences, and COVID-19 outcomes, guiding healthcare strategies and future research, and refining responses to the ongoing pandemic. In this study, analysis of COVID-19 studies centered on compiling risk assessments, including 95% confidence intervals along with odds and hazard ratios. The analysis's goal was to gather and assess the different risk metrics provided in this study.

References

World Health Organization. Coronavirus disease (COVID-19) outbreak https://www.who.int/emergencies/diseases/ novel-coronavirus-2019/situation-reports

Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, Cao B. Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China. The Lancet 2020; 395(10223): 497-506. DOI: https://doi.org/10.1016/S0140-6736(20)30183-5

Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, Zhang L. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. The Lancet 2020; 395(10223): 507-513. DOI: https://doi.org/10.1016/S0140-6736(20)30211-7

Wang L, He W, Yu X, Hu D, Bao M, Liu H, Jiang H. Coronavirus disease 2019 in elderly patients: characteristics and prognostic factors based on 4-week follow- up. Journal of Infection 2020; 80(6): 639-645. DOI: https://doi.org/10.1016/j.jinf.2020.03.019

Burki TK. Cancer care in the time of COVID-19. The Lancet Oncology 2020; 21(5): 628. DOI: https://doi.org/10.1016/S1470-2045(20)30201-1

Chen T, Wu DI, Chen H, Yan W, Yang D, Chen G, Ning Q. Clinical characteristics of 113 deceased patients with coronavirus disease 2019: retrospective study. BMJ 2020; 368. DOI: https://doi.org/10.1136/bmj.m1091

Shi S, Qin M, Shen B, Cai Y, Liu T, Yang F, Huang C. Association of cardiac injury with mortality in hospitalized patients with COVID-19 in Wuhan, China. JAMA Cardiology 2020; 5(7): 802-810. DOI: https://doi.org/10.1001/jamacardio.2020.0950

Hamming I, Timens W, Bulthuis MLC, Lely AT, Navis GV, van Goor H. Tissue distribution of ACE2 protein, the functional receptor for SARS coronavirus. A first step in understanding SARS pathogenesis. The Journal of Pathology: A Journal of the Pathological Society of Great Britain and Ireland 2004; 203(2): 631-637. DOI: https://doi.org/10.1002/path.1570

Danser AJ, Epstein M, Batlle D. Renin-angiotensin system blockers and the COVID-19 pandemic: at present there is no evidence to abandon renin-angiotensin system blockers. Hypertension 2020; 75(6): 1382-1385. DOI: https://doi.org/10.1161/HYPERTENSIONAHA.120.15082

Kim R, Emi M, Tanabe K. Cancer immunosuppression and autoimmune disease: beyond immunosuppressive networks for tumour immunity. Immunology 2006; 119(2): 254-264. DOI: https://doi.org/10.1111/j.1365-2567.2006.02430.x

Shankar A, Saini D, Roy S, Jarrahi AM, Chakraborty A, Bharati SJ, Taghizadeh-Hesary F. Cancer care delivery challenges amidst coronavirus disease–19 (COVID-19) outbreak: specific precautions for cancer patients and cancer care providers to prevent spread. Asian Pacific journal of cancer prevention: APJCP 2020; 21(3): 569-573. DOI: https://doi.org/10.31557/APJCP.2020.21.3.569

Danish F, Salam S. Statistical evaluation and global distribution of early COVID-19 outbreak. LOJ Medical Sciences 2020; 5(3).

Zhou F, Yu T, Du R, Fan G, Liu Y, Liu Z, Cao B. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. The Lancet 2020; 395(10229): 1054-1062. DOI: https://doi.org/10.1016/S0140-6736(20)30566-3

Pranata R, Huang I, Lukito AA, Raharjo SB. Elevated N-terminal pro-brain natriuretic peptide is associated with increased mortality in patients with COVID-19: systematic review and meta-analysis. Postgraduate Medical Journal 2020; 96(1137): 387-391. DOI: https://doi.org/10.1136/postgradmedj-2020-137884

Yusuf S, Joseph P, Rangarajan S, Islam S, Mente A, Hystad P, Dagenais G. Modifiable risk factors, cardiovascular disease, and mortality in 155 722 individuals from 21 high-income, middle-income, and low-income countries (PURE): a prospective cohort study. The Lancet 2020; 395(10226): 795-808. DOI: https://doi.org/10.1016/S0140-6736(19)32008-2

Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, Zhang L. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. The Lancet 2020; 395(10223): 507-513. DOI: https://doi.org/10.1016/S0140-6736(20)30211-7

Aggarwal G, Lippi G, Michael Henry B. Cerebrovascular disease is associated with an increased disease severity in patients with coronavirus disease 2019 (COVID-19): a pooled analysis of published literature. International Journal of Stroke 2020;15(4): 385-389. DOI: https://doi.org/10.1177/1747493020921664

Chen J, Bai H, Liu J, Chen G, Liao Q, Yang J, Li K. Distinct clinical characteristics and risk factors for mortality in female COVID-19 inpatients: a sex-stratified large-scale cohort study in Wuhan, China. Clinical infectious diseases: an official publication of the Infectious Diseases Society of America 2020. DOI: https://doi.org/10.1093/cid/ciaa920

Ashrafi F, Zali A, Ommi D, Salari M, Fatemi A, Arab-Ahmadi M, Advani S. COVID-19-related strokes in adults below 55 years of age: a case series. Neurological Sciences 2020; 41: 1985-1989. DOI: https://doi.org/10.1007/s10072-020-04521-3

Chen R, Liang W, Jiang M, Guan W, Zhan C, Wang T, for COVID MTEG. Risk factors of fatal outcome in hospitalized subjects with coronavirus disease 2019 from a nationwide analysis in China. Chest 2020; 158(1): 97-105. DOI: https://doi.org/10.1016/j.chest.2020.04.010

Palaiodimos L, Kokkinidis DG, Li W, Karamanis D, Ognibene J, Arora S, Mantzoros CS. Severe obesity, increasing age and male sex are independently associated with worse in-hospital outcomes, and higher in-hospital mortality, in a cohort of patients with COVID-19 in the Bronx, New York. Metabolism 2020; 108: 154262. DOI: https://doi.org/10.1016/j.metabol.2020.154262

Liang X, Shi L, Wang Y, Xiao W, Duan G, Yang H, Wang Y. The association of hypertension with the severity and mortality of COVID-19 patients: Evidence based on adjusted effect estimates. Journal of Infection 2020; 81(3): e44-e47. DOI: https://doi.org/10.1016/j.jinf.2020.06.060

Zhang Y, Cui Y, Shen M, Zhang J, Liu B, Dai M, Pan P. Comorbid diabetes mellitus was associated with poorer prognosis in patients with COVID-19: a retrospective cohort study. MedRxiv 2020; 2020-03. DOI: https://doi.org/10.1101/2020.03.24.20042358

Guan WJ, Liang WH, Zhao Y, Liang HR, Chen ZS, Li YM, He JX. Comorbidity and its impact on 1590 patients with COVID-19 in China: a nationwide analysis. European Respiratory Journal 2020; 55(5). DOI: https://doi.org/10.1183/13993003.01227-2020

Yu J, Ouyang W, Chua ML, Xie C. SARS-CoV-2 transmission in patients with cancer at a tertiary care hospital in Wuhan, China. JAMA Oncology 2020; 6(7): 1108-1110. DOI: https://doi.org/10.1001/jamaoncol.2020.0980

Du RH, Liang LR, Yang CQ, Wang W, Cao TZ, Li M, Shi HZ. Predictors of mortality for patients with COVID-19 pneumonia caused by SARS-CoV-2: a prospective cohort study. European Respiratory Journal 2020; 55(5). DOI: https://doi.org/10.1183/13993003.00524-2020

Mehra MR, Desai SS, Kuy S, Henry TD, Patel AN. Car-diovascular disease, drug therapy, and mortality in Covid-19. New England Journal of Medicine 2020; 382(25): e102. DOI: https://doi.org/10.1056/NEJMoa2007621

Suleyman G, Fadel RA, Malette KM, Hammond C, Abdulla H, Entz A, Brar I. Clinical characteristics and morbidity associated with coronavirus disease 2019 in a series of patients in metropolitan Detroit. JAMA Network Open 2020; 3(6): e2012270-e2012270. DOI: https://doi.org/10.1001/jamanetworkopen.2020.12270

Chen Y, Yang D, Cheng B, Chen J, Peng A, Yang C, Huang K. Clinical characteristics and outcomes of patients with diabetes and COVID-19 in association with glucose-lowering medication. Diabetes Care 2020; 43(7): 1399-1407. DOI: https://doi.org/10.2337/dc20-0660

Cummings MJ, Baldwin MR, Abrams D, Jacobson SD, Meyer BJ, Balough EM, O'Donnell MR. Epidemiology, clinical course, and outcomes of critically ill adults with COVID-19 in New York City: a prospective cohort study. The Lancet 2020; 395(10239): 1763- 1770. DOI: https://doi.org/10.1016/S0140-6736(20)31189-2

Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, Peng Z. Clinical characteristics of 138 hospitalized patients with 2019 novel coronavirus–infected pneumonia in Wuhan, China. JAMA 2020; 323(11): 1061-1069. DOI: https://doi.org/10.1001/jama.2020.1585

De Smet R, Mellaerts B, Vandewinckele H, Lybeert P, Frans E, Ombelet S, Laurent MR. Frailty and mortality in hospitalized older adults with COVID-19: retrospective observational study. Journal of the American Medical Directors Association 2020; 21(7): 928-932. DOI: https://doi.org/10.1016/j.jamda.2020.06.008

Fu L, Fei J, Xiang HX, Xiang Y, Tan ZX, Li MD, Xu DX. Influence factors of death risk among COVID-19 patients in Wuhan, China: a hospital-based case-cohort study. MedRxiv 2020; 2020-03. DOI: https://doi.org/10.21203/rs.3.rs-26775/v1

Cheng Y, Luo R, Wang K, Zhang M, Wang Z, Dong L, Xu G. Kidney disease is associated with in-hospital death of patients with COVID-19. Kidney International 2020; 97(5): 829-838. DOI: https://doi.org/10.1016/j.kint.2020.03.005

Nepogodiev D, Bhangu A, Glasbey JC, Li E, Omar OM, Simoes JF, Fernandez AG. Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study. The Lancet 2020; 396(10243): 27-38. DOI: https://doi.org/10.1016/S0140-6736(20)31182-X

Zhang F, Yang D, Li J, Gao P, Chen T, Cheng Z, He L. Myocardial injury is associated with in-hospital mortality of confirmed or suspected COVID-19 in Wuhan, China: A single center retrospective cohort study. MedRxiv 2020; 2020-03. DOI: https://doi.org/10.1101/2020.03.21.20040121

Li X, Xu S, Yu M, Wang K, Tao Y, Zhou Y, Zhao J. Risk factors for severity and mortality in adult COVID-19 inpatients in Wuhan. Journal of Allergy and Clinical Immunology 2020; 146(1): 110-118. DOI: https://doi.org/10.1016/j.jaci.2020.04.006

Chesnut WM, MacDonald S, Wambier CG. Could diet and exercise reduce risk of COVID-19 syndemic? Medical Hypotheses 2021; 148: 110502. DOI: https://doi.org/10.1016/j.mehy.2021.110502

Kollias A, Kyriakoulis KG, Kyriakoulis IG, Nitsotolis T, Poulakou G, Stergiou GS, Syrigos K. Statin use and mortality in COVID-19 patients: Updated systematic review and meta-analysis. Atherosclerosis 2021; 330: 114-121. DOI: https://doi.org/10.1016/j.atherosclerosis.2021.06.911

Larvin H, Wilmott S, Kang J, Aggarwal VR, Pavitt S, Wu J. Additive effect of periodontal disease and obesity on COVID-19 outcomes. Journal of Dental Research 2021; 100(11): 1228-1235. DOI: https://doi.org/10.1177/00220345211029638

Namendys-Silva SA, Alvarado-Ávila PE, Domínguez-Cherit G, Rivero-Sigarroa E, Sánchez-Hurtado LA, Gutiérrez-Villaseñor A, Mexico COVID-19 Critical Care Collaborative Group. Outcomes of patients with COVID-19 in the intensive care unit in Mexico: A multicenter observational study. Heart Lung 2021; 50(1): 28-32. DOI: https://doi.org/10.1016/j.hrtlng.2020.10.013

Rahmani K, Shavaleh R, Forouhi M, Disfani HF, Kamandi M, Oskooi RK, Dianatinasab M. The effectiveness of COVID-19 vaccines in reducing the incidence, hospitalization, and mortality from COVID-19: A systematic review and meta-analysis. Frontiers in Public Health 2022; 10: 2738. DOI: https://doi.org/10.3389/fpubh.2022.873596

Bramante CT, Buse JB, Liebovitz DM, Nicklas JM, Puskarich MA, Cohen K, Zinkl L. Outpatient treatment of COVID-19 and incidence of post-COVID-19 condition over 10 months (COVID-OUT): a multicentre, randomised, quadruple-blind, parallel-group, phase 3 trial. The Lancet Infectious Diseases 2023; 23(10): 1119-1129. DOI: https://doi.org/10.1016/S1473-3099(23)00299-2

El-Qushayri AE, Dahy A, Benmelouka AY, Kamel AMA. The effect of COVID-19 on the in-hospital outcomes of percutaneous coronary intervention in patients with acute coronary syndrome: A large scale meta-analysis. American Journal of Medicine Open 2023; 9: 100032. DOI: https://doi.org/10.1016/j.ajmo.2023.100032

Evans A, Qi C, Adebayo JO, Underwood J, Coulson J, Bailey R, Akbari A. Real-world effectiveness of molnupiravir, nirmatrelvir-ritonavir, and sotrovimab on preventing hospital admission among higher-risk patients with COVID-19 in Wales: A retrospective cohort study. Journal of Infection 2023; 86(4): 352-360. DOI: https://doi.org/10.1016/j.jinf.2023.02.012

Gul MH, Htun ZM, de Jesus Perez V, Suleman M, Arshad S, Imran M, Morris PE. Predictors and outcomes of acute pulmonary embolism in COVID-19; insights from US National COVID cohort collaborative. Respiratory Research 2023; 24(1): 1-12. DOI: https://doi.org/10.1186/s12931-023-02369-7

Isla A, Landy D, Teasdall R, Mittwede P, Albano A, Tornetta III P, Aneja A. Postoperative mortality in the COVID-positive hip fracture patient, a systematic review and meta-analysis. European Journal of Orthopaedic Surgery Traumatology 2023; 33(4): 927-935. DOI: https://doi.org/10.1007/s00590-022-03228-9

Kwok WC, Leung SHI, Tam TCC, Ho JCM, Lam DCL, Ip MSM, Ho PL. Efficacy of mRNA and inactivated whole virus vaccines against COVID-19 in patients with chronic respiratory diseases. International Journal of Chronic Obstructive Pulmonary Disease 2023; 47-56. DOI: https://doi.org/10.2147/COPD.S394101

Mak JK, Eriksdotter M, Annetorp M, Kuja-Halkola R, Kananen L, Boström AM, Jylhävä J. Two Years with COVID-19: The Electronic Frailty Index Identifies High-Risk Patients in the Stockholm GeroCovid Study. Gerontology 2023; 69(4): 396-405. DOI: https://doi.org/10.1159/000527206

Miyashita K, Hozumi H, Furuhashi K, Nakatani E, Inoue Y, Yasui H, Suda T. Changes in the characteristics and outcomes of COVID-19 patients from the early pandemic to the delta variant epidemic: a nationwide population-based study. Emerging Microbes Infections 2023; 12(1): 2155250. DOI: https://doi.org/10.1080/22221751.2022.2155250

Hulme WJ, Horne EM, Parker EP, Keogh RH, Williamson EJ, Walker V, Sterne JA. Comparative effectiveness of BNT162b2 versus mRNA-1273 covid-19 vaccine boosting in England: matched cohort study in OpenSAFELY-TPP. BMJ 2023; 380. DOI: https://doi.org/10.1136/bmj-2022-072808

Hyman S, Zhang J, Andersen ZJ, Cruickshank S, Møller P, Daras K, Lim YH. Long-term exposure to air pollution and COVID-19 severity: A cohort study in Greater Manchester, United Kingdom. Environmental Pollution 2023; 327: 121594. DOI: https://doi.org/10.1016/j.envpol.2023.121594

Huang S, Vieillard-Baron A, Evrard B, Prat G, Chew MS, Balik M, Vignon P. Echocardiography phenotypes of right ventricular involvement in COVID-19 ARDS patients and ICU mortality: Post-hoc (exploratory) analysis of repeated data from the ECHO- COVID study. Intensive Care Medicine 2023; 49(8): 946-956. DOI: https://doi.org/10.1007/s00134-023-07147-z

Reis G, Moreira Silva EA, Medeiros Silva DC, Thabane L, Campos VH, Ferreira TS, Glenn JS. Early treatment with pegylated interferon lambda for covid-19. New England Journal of Medicine 2023; 388(6): 518-528. DOI: https://doi.org/10.1056/NEJMoa2209760

Surendra H, Elyazar IR, Puspaningrum E, Darmawan D, Pakasi TT, Lukitosari E, Hamers RL. Impact of the COVID-19 pandemic on tuberculosis control in Indonesia: a nationwide longitudinal analysis of programme data. The Lancet Global Health 2023; 11(9): e1412- e1421. DOI: https://doi.org/10.1016/S2214-109X(23)00312-1

Tran A, Fernando SM, Rochwerg B, Barbaro RP, Hodgson CL, Munshi L, Brodie D. Prognostic factors associated with mortality among patients receiving venovenous extracorporeal membrane oxygenation for COVID-19: a systematic review and meta-analysis. The Lancet Respiratory Medicine 2023; 11(3): 235-244. DOI: https://doi.org/10.1016/S2213-2600(22)00296-X

Tosato M, Calvani R, Ciciarello F, Galluzzo V, Martone AM, Zazzara MB, Landi F. Malnutrition in COVID-19 survivors: Prevalence and risk factors. Aging Clinical and Experimental Research 2023; 1-9. DOI: https://doi.org/10.1093/geroni/igad104.3462

Watanabe A, Iwagami M, Yasuhara J, Takagi H, Kuno T. Protective effect of COVID-19 vaccination against long COVID syndrome: A systematic review and meta- analysis. Vaccine 2023. DOI: https://doi.org/10.1016/j.vaccine.2023.02.008

Zeymer U, Ahmadli V, Schneider S, Werdan K, Weber M, Hohenstein S, Thiele H. Effects of the COVID-19 pandemic on acute coronary syndromes in Germany during the first wave: the COVID-19 collateral damage study. Clinical Research in Cardiology 2023; 112(4): 539-549. DOI: https://doi.org/10.1007/s00392-022-02082-3

Zuin M, Barco S, Giannakoulas G, Engelen MM, Hobohm L, Valerio L, Konstantinides SV. Risk of venous thromboembolic events after COVID-19 infection: a systematic review and meta-analysis. Journal of Thrombosis and Thrombolysis 2023; 1-9. DOI: https://doi.org/10.1007/s11239-022-02766-7

Fiore AE, Uyeki TM, Broder K, Finelli L, Euler GL, Singleton JA, Cox NJ. Prevention and control of influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP): 2010. Department of Health and Human Services, Centers for Disease Control and Prevention 2010.

Remschmidt C, Wichmann O, Harder T. Vaccines for the prevention of seasonal influenza in patients with diabetes: systematic review and meta-analysis. BMC Medicine 2015; 13(1): 1-11. DOI: https://doi.org/10.1186/s12916-015-0295-6

Moriyama M, Hugentobler WJ, Iwasaki A. Seasonality of respiratory viral infections. Annual Review of Virology 2020; 7: 83-101. DOI: https://doi.org/10.1146/annurev-virology-012420-022445

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2025-08-04

How to Cite

Khan, M. R. ., Danish, F. ., Ahmed Araibi, M. I. ., Elbatal, I. ., Almetwally, E. M. ., Gemeay, A. M. ., Triveni, G. ., Jan, R. ., Reddy, V. ., & Rather, A. A. . (2025). Statistical Evaluation of Comorbidities and Environmental Factors in COVID-19 Outcomes: Risk Measures and Predictive Analysis Using Odds and Hazard Ratios. International Journal of Statistics in Medical Research, 14, 416–429. https://doi.org/10.6000/1929-6029.2025.14.40

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Vol. 14 (2025)

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