Systematic Review Article     Jan-June 2021  

Clinical Characteristics and Outcomes among Patients with Covid-19 in Different Regions of the World

By Yuanlin Zhou1, Huihai Fan1

Affiliations

  1. Department of Pediatrics, The Sixth People's Hospital of Chengdu, China

ABSTRACT
The SARS-CoV-2 outbreak began in China in December 2019 and rapidly spread globally. Up to July 2020, the number of cases of coronavirus disease 2019 (COVID-19) had been increasing in the USA, Italy, England, Spain and numerous other countries. Patients with this disease in different countries present with different clinical manifestations and different prognosis. The present study aimed to analyse the clinical characteristics of patients infected with SARS-CoV-2 in different regions of the world and provide special advices for the different regions to prevent the spread and a second outbreak of COVID-19.

Key Words: COVID-19, SARS-CoV-2, Characteristics, Worldwide.

INTRODUCTION

The novel coronavirus severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) has been rapidly spreading worldwide, with >10 million patients infected with this disease. Up to July 2020, the number of cases of coronavirus disease 2019 (COVID-19) had been increasing in the USA, Italy, England, Spain and numerous other countries.1-4 There have been ~13 million reported cases of this pandemic and >500,000 deaths. This disease was originated in Wuhan (Hubei, China).5 SARS-CoV-2 has been classified into A, B and C types, according to the gene variants.6 Different countries are associated with different SARS-CoV-2 types. European and American patients are mostly infected with the A and C types, while East Asian patients with B type.6 Patients with this disease in different countries present with different clinical characteristics including demographics, clinical presentations, comorbidities, and mortalities. It was reported that the median patient age was 52 years in China;7 however, the median age of the patients was 40 years in Korea.8 The most common symptoms included fever (85.81%; 399 of 465) on admission, followed by cough (67.10%; 312 of 465) in China.9 In Poland, the most common symptoms of COVID-19 were fever (43.78%; 74 of 169), shortness of breath (36.09%; 61 of 169), and fatigue (33.73%; 57 of 169).10 However, the most common symptoms were cough (73.8%; 738 of 1,000), and fever (72.8%; 728 of 1,000), followed by dyspnea (63.10%; 631 of 1000) in the USA.11

The aim of this review was to assess the characteristics of COVID-19 among different countries. The healthcare data of patients with COVID-19 reported worldwide, which may provide specific suggestions for different countries for the diagnosis and prevention of a second outbreak of COVID-19.

METHODOLOGY

Literature review was conducted according to preferred reporting items for systematic reviews and meta-analyses guidelines. Medline, Embase and Web of Science databases were searched between December 1, 2019 and April 30, 2020. The search strategy used a combination of MeSH terms and free terms: ‘2019-nCOV’ or ‘SARS-CoV-2’ or ‘COVID19’ and ‘clinical feature’ or ‘clinical characteristics’ or ‘symptom’ or ‘manifestation’. Searches were limited to literature published in English.

Studies published in English language about the clinical characteristics, including demographics, clinical presentation, comorbidities and mortality of covid19 were selected. The inclusion criteria were full manuscript on the clinical characteristics of patients with SARS-CoV-2 infection. All the patients in these studies were confirmed with SARS-CoV-2 by laboratory test with a positive result on the reverse transcriptase polymerase chain reaction assay for SARS-CoV-2. Articles with incomplete information, review articles, editorial, case reports, ongoing studies and guidelines were excluded. Two investigators reviewed each full-text articles and finished the studies selection independently. Selected studies were checked together and the disagreements were resolved through consensus. Of the 522 studies reviewed (Figure 1), 27 articles were finally selected. All the patients in the 27 articles were included in this study.

Primary outcome is discharge; and second outcome is remained in hospital. Characteristic included demographics, clinical presentations, comorbidities and mortalities. Data about the characteristics including demographics, clinical presentations, comorbidities and mortalities in these studies were extracted by independent investigators. Then the investigators verified the data together. Controversies among investigators were solved by discussion or counselling evidence-based medicine experts in the department. Quality of evidence for randomised studies was assessed according to the cochrane collaboration’s tool for assessing risk of bias, and the Newcastle Ottawa scale was used to assess quality of nonrandomised studies.

Five hundred and twenty-two studies were reviewed (Figure 1), and 27 articles were finally selected. The data was analysed through Chi-square test and Fisher’s exact test, as appropriate. All statistical analyses were performed using the IBM SPSS version 20.0. Confidence interval (CI) is 95%. A p-value of less than 0.05 was considered to be statistically significant.

Figure 1: Prisma flow diagram showing the literature research and selection strategy.

RESULTS

A total of 38,753 patients from 27 studies were included in the present study. Characteristics of the studies included in the systematic analysis are listed in Table I.

Before March, the COVID-19 outbreak mainly occurred in Asia. A total of 97.51% (1,723 of 1,767) of the COVID-19 cases were located in Asia. Between March and April, 55.25% (20,425 of 36,968) of COVID-19 cases were found in Europe, with Europe becoming the new main site of the COVID-19 outbreak. Concurrently, the disease began to rapidly spread in the USA, with a total of 33.92% (12,541 of 36,968) cases of COVID-19 occurring in the USA.

To assess the characteristics of COVID-19 according to the month of presentation, the clinical manifestations of COVID-19 reported before March and between March and April were analysed (Table II).

Based on the results, hypertension was among the most common comorbidities. In addition to liver disease and HIV, patients with neurological disorders, chronic lung disease and diabetes mellitus had more COVID-19 in March and April, compared with before March. Fever and cough were the most common symptoms of COVID-19. As regards dyspnea in the context of COVID-19, the proportion of patients with dyspnea between March and April was 58.47% compared to 14.50% before the period as above.

To date, the COVID-19 outbreak was mainly spread in Asia, Europe and USA. Hence, the world was divided into three regions (Asia, Europe and USA). The characteristics of patients with COVID-19 were compared among different regions of the world (Table III).

 The compared characteristics included comorbidities, symptoms and outcomes. The comorbidity rates of patients with COVID-19 vary across different areas, ranging between 0.90 and 55.01%. The hypertension rate was 55.01% in the USA, while it was 44.56% in Europe and 7.81% in Asia.

In Asia, only 3.97% of the patients had heart disease, whereas 17.95% of patients in Europe and 33.2% of those in the USA had heart disease. The rates of diabetes mellitus in Europe (15.67%) and in the USA (28.61%) were also higher compared with those in Asia (5.37%). Similar to the aforementioned comorbidities, 15.50% patients with COVID-19 in Europe and 18.34% in the USA had chronic lung disease, which was higher compared with the reported percentage in Asia (4.00%). By contrast, liver disease is more common as comorbidity among Asians (3.24%).

Next, the symptoms of COVID-19 were compared among Asia, Europe and the USA. The most common symptoms of COVID-19 were fever, coughing and shortness of breath, observed in all regions of the world. However, compared to Asia, the incidence of dyspnea among COVID-19 patients in Europe and the USA is higher. Myalgia is less common in Europe, accounting for only 4.17%, as 26.65% of the patients in the USA suffered from myalgia. As regards nausea and vomiting, only 4.46% and 3.55% had this symptom in Asia and Europe, respectively as compared with 17.80% in USA. Diarrhea was reported in 6.14% in Asia and 5.16% in Europe, whereas 21.32% of patients with COVID-19 in the USA had diarrhea.

Finally, the outcome of COVID-19 among Asia, Europe and USA were compared. In the present study, 41% of patients were discharged overall, 74.12% were discharged in Asia and 40.56% were discharged in Europe. In the USA, 35.62% of patients were discharged, which is lower compared with in Asia. A total of 37.54% of patients in all reported data still remained in hospital to receive treatment, where 18.94% remained in hospital in Asia, compared to 33.86% in Europe. Additionally, 51.34% (5,925/11,541) of patients remained in hospital in the USA. The rates of patients remaining in hospital in the USA and Europe were higher compared with in Asia. Around 25.60% patients died with COVID-19 in Europe, which is higher compared with Asia (6.46%) and the USA (12.58%).

DISCUSSION

The present study described the characteristics of 38,753 patients with COVID-19; worldwide between December 1st 2019 and April 30th, 2020. This disease was first reported in Wuhan, China and rapidly spread to other countries, including Korea, USA, Italy and Iran, among others.29

Table I: Characteristics of studies and patients included in the systematic analysis.

Authors

Time

Region

Sample

Median age

Males (%)

Study type

Zhongwei Xiong7

February 9th to March 5, 2020

China

421

52 (39–61)

214

retrospective study

single-centerstudy

Jiangshan Lian9

January 17, 2020, to January 31

China

465

45(5-88)

243 (52.26%)

retrospective study

multicenter study

Marta Colaneri [2

February 21 to 28

Italy

44

67.5

28

retrospective study

single-center study

Dawei Wang 13

January 1 to 28

China

138

56(42-28)

63

retrospective study

single-center study

Mengyao Ji14

January 2 to to 28

China

101

51.0 (37.0–61.0)

48 (48%)

retrospective study

single-center study

Michael G Argenziano11

March 1 to April 5

USA

1000

63.0 (50.0-75.0)

596

retrospective study

single-center study

Annemarie B Docherty15

February 6 to and 19 April 2020.

UK

20133

72.9 (58.0-82.0)

12 068 (59.9)

prospective cohort study

multicenter study

Christopher M Petrilli16

March 1 2020 to 8 April

USA

5279

54 (38-66)

2615 (49.5)

prospective cohort study

single-center study

Yalei Shanga17

January to 2020 to January 26

China

62

41 (32-52)

35 (56)

retrospective study

 multicenter study

Håkon Ihle-Hansen18

March 9 to 31 

Norway

42

72.5

28

retrospective study

single-center study

Helena Barrasa2

March 1 to 31

Spain

48

63 (12)

27 (56%)

prospective cohort study

 multicenter study

Mohamad Nikpouraghdam4

February 19 2020 to April 15 2020

Iran

2964

56(46–65)

1955

retrospective study

single-center study

Guqin Zhang[9

February 2 to 10, 2020.

China

221

55.0 (39.0–66.5)

108

retrospective study

single-center study

Ying Sun20

Before April

China

63

47

37

unclear

unclear

Simone Piva3

March 2 and March 13

Italy

33

64 (59–72)

30

prospective cohort study

single-center study

Wenjie Yang21

January 17 to February 10

China

149

45.11 ± 13.35

81

retrospective study

multicenter study

Matthew J Cummings22

March 2 to April 1, 2020

USA

257

62 (51–72)

171

prospective cohort study

multicenter study

Yalei Shang[7

January 10th 2020 to March

China

307

46(33, 55)

164

prospective cohort study

multicenter study

Chaolin Huang

January 2, 2020

China

41

49.0 (41.0–58.0)

30

prospective cohort study

single-center study

Nanshan Chen23

January 1 to Jan 20, 2020

China

99

55.5 (13.1)

67 (68%)

retrospective study

single-centre study

Eu Suk Kim 8

January 19 2020 to February 17, 2020

Korea

28

42.6 ± 13.4

15 (53.6)

prospective cohort study

multicenter study

Rui Huang24

January 22, 2020 to February10, 2020

China

202

44.0 (33.0, 54.0)

116 (57.4)

retrospective study

multicenter study

Yiwu Zhou25

January 20, 2019, and February 8, 2020.

China

366

43 (31.8–51.0)

207 (56.6)

retrospective study

 multicenter study

Jeremy A W Gold26

March 1 to March 30, 2020

USA

305

60(46–69)

49.50%

prospective cohort study

multicenter study

Błażej Nowak10

March 16, 2020 and 2020/4/7

Poland

169

63.7 (19.6)

87

retrospective  study

single-center study

Safiya Richardson27

March 1, 2020, and April 4, 2020

USA

5700

63 (52-75)

3437

unclear

multicenter study

Kyung Soo Hong28

Before March 29th

Korea

98

55.4±17.1

38.00

retrospective study

single-center study

The disease characteristics, such as admission rates, fatality rates and symptoms, vary widely among different regions of the world.9-11

The aim of the present study was to comprehensively analyse the characteristics of COVID-19 and analyse the risk factors of COVID-19; in different regions of the world providing personal suggestions for the different regions. It was observed that patients in the USA had the highest rate of comorbidities such as hypertension, heart disease, chronic lung disease, and diabetes mellitus; whereas in Asia, the most common comorbidities were liver diseases and HIV infection. This finding indicates that Europe and the USA must improve the screening and preventive measures for COVID-19 in patients with hypertension, heart disease, chronic lung disease and diabetes mellitus, particularly those with hypertension and/or heart diseases. As regards the clinical symptoms, fever and cough are the most common symptoms worldwide; whereas, the incidence of dyspnea is higher among patients with COVID-19 in Europe and the USA. This finding indicates that, in addition to fever and cough, screening for dyspnea is important for preventing the spread of SARS-CoV-2. This phenomenon may be partially attributed to the high proportion of related comorbidities in patients from Europe and the USA.


Table II: Characteristics of patients with COVID-19 before March and March-April.

 

Before March

March-April

p

Comorbidities

Heart diseases

8.41%

 21.75%  

0.000

Neurologic disorder

2.94%

11.96%

0.000

Chronic lung disease

1.94%

15.37%

0.000

Diabetes mellitus

7.15%

19.17%

0.000

Hypertension

18.23%

39.68%

0.000

Liver disease

3.27%

1.66%

0.000

Malignancy

2.86%

5.52%

0.000

Kidney disease

1.56%

8.51%

0.000

HIV

2.24%

0.47%

0.000

Symptoms

Fever

74.98%

62.77%

0.000

Cough

52.53%

63.85%

0.000

Sputum

57.05%

8.89%

0.000

Myalgia

13.52%

23.28%

0.000

Fatigue

27.65%

23.11%

0.047

Short of breath

14.50%

58.47%

0.000

Nausea and vomiting

4.78%

13.21%

0.000

Diarrhea

7.23%

13.89%

0.000

Headache

9.22%

9.03%

 

Rhinorrhoea

3.33%

7.50%

0.002

Sore throat

11.86%

9.10%

0.051

Clinical outcomes

Remains in hospital

62.55%

36.70%

0.000

Discharged

30.94%

43.57%

0.000

Died

3.88%

4.48%

0.478



Table III: Characteristics of COVID-19 patients among Asia, Europe and America.

 

Asia

Europe

America

p

Comorbidities

Heart diseases

w3.97%

17.95%

33.20%

0.000

Neurologic disorder

10.45%

11.99%

11.03%

0.209

Chronic lung disease

4.00%

15.50%

18.34%

0.000

Diabetes mellitus

5.37%

15.67%

28.61%

0.000

Hypertension

7.81%

44.56%

55.01%

0.000

Liver disease

3.24%

1.88%

1.05%

0.000

Malignancy

1.34%

5.70%

6.53%

0.000

Kidney disease

0.90%

8.41%

10.55%

0.000

HIV

2.25%

0.27%

1.04%a

0.000

Fever

72.08%

62.12%

72.47%

0.000

Cough

57.08%

63.76%

71.68%

0.000

Myalgia

15.30%

4.17%

26.65%

0.000

Short of breath/dyspnea

12.38%

59.94%

65.31%

0.000

Nausea and vomiting

4.46%

3.55%

17.80%

0.000

Diarrhea

6.14%

5.16%

21.32%

0.000

Clinical outcomes

Remains in hospital

18.94%

33.86%

51.34%

0.000

Discharged

74.12%

40.56%

35.62%

0.000

Died

6.46%

25.60%

12.58%

0.000

Patients in Asia had higher rates of discharge and lower rates of mortality compared with Europe and USA (p=0.000). In the USA, although the rate of discharge was the lowest among the three areas, the mortality of patients with COVID-19 was not the highest. A possible explanation may be the advanced medical technology available in the USA. However, the mortality rate of patients with COVID-19 in Europe was very high. The higher mortality rates of COVID-19 in Europe and USA may be due to the high rate of comorbidities, suggesting that more attention should be paid to patients with comorbidities, such as more health monitoring, more protective equipment, more supportive treatment etc.

CONCLUSION

COVID-19 has higher prevalence among patients with comorbidities, such as heart disease, chronic lung disease, and hypertension in the USA and Europe compared with Asia (p=0.000). Liver disease and HIV were risk factors associated with COVID-19 in Asia. Hence, patients with HIV and liver disease also should be closely followed in Asia to prevent the spread and a possible second outbreak of COVID-19. Furthermore, not only the symptoms such as fever and cough should be monitored; but also the dyspnea, myalgia, nausea, vomiting, and diarrhea should be screened in Europe and USA. The mortality rates in Europe and USA were significantly higher compared with that in Asia.

PATIENTS CONSENT:
The consents of the patients were taken prior to the writing of the manuscript.

CONFLICT OF INTEREST:
The authors declared no conflict of interest.

AUTHORS’ CONTRIBUTION:
ZY, FH: Contributed to the design of the work and acquisition, analysis, or interpretation of data for the work together. They worked on the drafting of the work or revising it critically for important intellectual content and approved the version to be published. They agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

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