Prevalence of Comorbidities in COVID-19 Patients: A Systematic Review and Meta-Analysis



1 Orthopedic Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

2 Department of Surgery, McGill University, Canada


Background: In this study, we aimed to assess the prevalence of comorbidities in the confirmed COVID-19 patients. This
might help showing which comorbidity might pose the patients at risk of more severe symptoms.
Methods: We searched all relevant databases on April 7th, 2020 using the keywords (“novel coronavirus” OR COVID-19
OR SARS-CoV-2 OR Coronavirus) AND (comorbidities OR clinical characteristics OR epidemiologic*). We reviewed 33
papers’ full text out of 1053 papers. There were 32 papers from China and 1 from Taiwan. There was no language or
study level limit. Prevalence of comorbidities including hypertension, diabetes mellitus, cardiovascular disease, chronic
lung disease, chronic kidney disease, malignancies, cerebrovascular diseases, chronic liver disease and smoking were
extracted to measure the pooled estimates. We used OpenMeta and used random-effect model to do a single arm
Results: The mean age of the diagnosed patients was 51 years. The male to female ratio was 55 to 45. The most
prevalent finding in the confirmed COVID-19 patients was hypertension, which was found in 1/5 of the patients (21%).
Other most prevalent finding was diabetes mellitus (DM) in 11%, cerebrovascular disease in 2.4%, cardiovascular
disease in 5.8%, chronic kidney disease in 3.6%, chronic liver disease in 2.9%, chronic pulmonary disease in 2.0%,
malignancy in 2.7%, and smoking in 8.7% of the patients.
Conclusion: COVID-19 infection seems to be affecting every race, sex, age, irrespective of health status. The risk of
symptomatic and severe disease might be higher due to the higher age which is usually accompanied with comorbidities.
However, comorbidities do not seem to be the prerequisite for symptomatic and severe COVID-19 infection, except
Level of evidence: IV


1. Wallace BC, Dahabreh IJ, Trikalinos TA, Lau J, Trow P,
Schmid CH. Closing the gap between methodologists
and end-users: R as a computational back-end. J Stat
Softw. 2012; 49(5):1-15.
2. Hsih WH, Cheng MY, Ho MW, Chou CH, Lin PC, Chi
CY, et al. Featuring COVID-19 cases via screening
symptomatic patients with epidemiologic link during
flu season in a medical center of central Taiwan. J
Microbiol Immunol Infect. 2020; In Press.
3. Cai Q, Huang D, Ou P, Yu H, Zhu Z, Xia Z, et al. COVID-19
in a designated infectious diseases hospital outside
Hubei province, China. Allergy. 2020; In Press.
4. Cao J, Tu WJ, Cheng W, Yu L, Liu YK, Hu X, et al. Clinical
features and short-term outcomes of 102 patients
with corona virus disease 2019 in Wuhan, China. Clin
Infect Dis. 2020; 2:ciaa243.
5. Chen N, Zhou M, Dong X, Qu J, Gong F, Han Y, et al.
Epidemiological and clinical characteristics of 99
cases of 2019 novel coronavirus pneumonia in
Wuhan, China: a descriptive study. Lancet. 2020;
6. Chen T, Wu D, Chen H, Yan W, Yang D, Chen G, et al.
Clinical characteristics of 113 deceased patients with
coronavirus disease 2019: retrospective study. BMJ.
2020; 368(1):m1091.
7. Cheng Y, Luo R, Wang K, Zhang M, Wang Z, Dong L,
et al. Kidney disease is associated with in-hospital
death of patients with COVID-19. Kidney Int. 2020;
8. Deng Y, Liu W, Liu K, Fang YY, Shang J, Zhou L, et al.
Clinical characteristics of fatal and recovered cases
of coronavirus disease 2019 (COVID-19) in Wuhan,
China: a retrospective study. Chin Med J (Engl). 2020;
In Press.
9. Du Y, Tu L, Zhu P, Mu M, Wang R, Yang P, et al. Clinical
features of 85 fatal cases of COVID-19 from Wuhan:
a retrospective observational study. Am J Respir Crit
Care Med. 2020; In Press.
10. Guan WJ, Liang WH, Zhao Y, Liang HR, Chen ZS, Li YM,
et al. Comorbidity and its impact on 1590 patients
with Covid-19 in China: a nationwide analysis. Eur
Respir J. 2020; 26:2000547.
11. Guan WJ, Ni ZY, Hu Y, Liang WH, Ou CQ, He JX, et al.
Clinical characteristics of coronavirus disease 2019 in
China. N Engl J Med. 2020; In Press.
12. Guo W, Li M, Dong Y, Zhou H, Zhang Z, Tian C, et al.
Diabetes is a risk factor for the progression and
prognosis of COVID-19. Diabetes Metab Res Rev.
2020; 31(1):e3319.
13. Han YN, Feng ZW, Sun LN, Ren XX, Wang H, Xue YM,
et al. A comparative-descriptive analysis of clinical
characteristics in 2019-Coronavirus-infected children
and adults. J Med Virol. 2020; In Press.
14. Huang C, Wang Y, Li X, Ren L, Zhao J, Hu Y, et al.
Clinical features of patients infected with 2019
novel coronavirus in Wuhan, China. Lancet. 2020;
15. Jin X, Lian JS, Hu JH, Gao J, Zheng L, Zhang YM,
et al. Epidemiological, clinical and virological
characteristics of 74 cases of coronavirus-infected
disease 2019 (COVID-19) with gastrointestinal
symptoms. Gut. 2020; In Press.
16. Li J, Li S, Cai Y, Liu Q, Li X, Zeng Z, et al. Epidemiological
and clinical characteristics of 17 hospitalized patients
with 2019 novel coronavirus infections outside
Wuhan, China. MedRxiv. 2020; In Press.
17. Lian J, Jin X, Hao S, Cai H, Zhang S, Zheng L, et al.
Analysis of epidemiological and clinical features
in older patients with corona virus disease 2019
(COVID-19) out of Wuhan. Clin Infect Dis. 2020;
18. Liang W, Guan W, Chen R, Wang W, Li J, Xu K, et al.
Cancer patients in SARS-CoV-2 infection: a nationwide
analysis in China. Lancet Oncol. 2020; 21(3):335-7.
19. Liu K, Fang YY, Deng Y, Liu W, Wang MF, Ma JP, et al.
Clinical characteristics of novel coronavirus cases
in tertiary hospitals in Hubei Province. Chin Med J
(Engl). 2020; In Press.
20. Liu W, Tao ZW, Lei W, Ming-Li Y, Kui L, Ling Z, et al.
Analysis of factors associated with disease outcomes
in hospitalized patients with 2019 novel coronavirus
disease. Chin Med J (Engl). 2020; In Press.
21. Liu Y, Yang Y, Zhang C, Huang F, Wang F, Yuan J, et al.
Clinical and biochemical indexes from 2019-nCoV
infected patients linked to viral loads and lung injury.
Sci China Life Sci. 2020; 63(3):364-74.
22. Tang X, Du R, Wang R, Cao T, Guan L, Yang C, et al.
Comparison of hospitalized patients with acute
respiratory distress syndrome caused by COVID-19
and H1N1. Chest. 2020; In Press.
23. Wang D, Hu B, Hu C, Zhu F, Liu X, Zhang J, et al. Clinical
characteristics of 138 hospitalized patients with 2019
novel coronavirus-infected pneumonia in Wuhan,
China. JAMA. 2020; In Press.
24. Wang L, He W, Yu X, Hu D, Bao M, Liu H, et al. Coronavirus
disease 2019 in elderly patients: characteristics and
prognostic factors based on 4-week follow-up. J Infect.
2020; In Press.
25. Wang R, Liao C, He H, Hu C, Wei Z, Hong Z, et al.
COVID-19 in hemodialysis patients: a report of 5
cases. Am J Kidney Dis. 2020; In Press.
26. Wang X, Fang J, Zhu Y, Chen L, Ding F, Zhou R, et al.
Clinical characteristics of non-critically ill patients
with novel coronavirus infection (COVID-19) in a
Fangcang Hospital. Clin Microbiol Infect. 2020; In
27. Wang Z, Yang B, Li Q, Wen L, Zhang R. Clinical features
of 69 cases with coronavirus disease 2019 in Wuhan,
China. Clin Infect Dis. 2020; 16:ciaa272.
28. Wu C, Chen X, Cai Y, Xia J, Zhou X, Xu S, et al. Risk factors
associated with acute respiratory distress syndrome
and death in patients with coronavirus disease 2019 
pneumonia in Wuhan, China. JAMA Intern Med. 2020;
In Press.
29. Wu J, Liu J, Zhao X, Liu C, Wang W, Wang D, et al.
Clinical characteristics of imported cases of COVID-19
in Jiangsu province: a multicenter descriptive study.
Clin Infect Dis. 2020; 29:ciaa199.
30. Xie H, Zhao J, Lian N, Lin S, Xie Q, Zhuo H. Clinical
characteristics of Non-ICU hospitalized patients
with coronavirus disease 2019 and liver injury: a
retrospective study. Liver Int. 2020; In Press.
31. Xu XW, Wu XX, Jiang XG, Xu KJ, Ying LJ, Ma CL, et al.
Clinical findings in a group of patients infected with
the 2019 novel coronavirus (SARS-Cov-2) outside of
Wuhan, China: retrospective case series. BMJ. 2020;
32. Zhang JJ, Dong X, Cao YY, Yuan YD, Yang YB, Yan YQ,
et al. Clinical characteristics of 140 patients infected
with SARS-CoV-2 in Wuhan, China. Allergy. 2020; In
33. Zhang L, Zhu F, Xie L, Wang C, Wang J, Chen R, et al.
Clinical characteristics of COVID-19-infected cancer
patients: a retrospective case study in three hospitals
within Wuhan, China. Ann Oncol. 2020; In Press.
34. Zhang X, Cai H, Hu J, Lian J, Gu J, Zhang S, et al.
Epidemiological, clinical characteristics of cases
of SARS-CoV-2 infection with abnormal imaging
findings. Int J Infect Dis. 2020; In Press.