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Table of Contents
ORIGINAL ARTICLE
Year : 2021  |  Volume : 4  |  Issue : 2  |  Page : 124-129

Epidemiological and clinical characteristics of fatalities from COVID-19 in Saudi Arabia: A multicentric, retrospective study


1 Global Center of Mass Gatherings Medicine, Ministry of Health, Imam Mohammed Ibn Saud Islamic University, Riyadh, Saudi Arabia
2 Department of Surgery, College of Medicine, Imam Mohammed Ibn Saud Islamic University, Riyadh, Saudi Arabia
3 Department of Emergency Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia

Date of Submission07-Sep-2020
Date of Decision06-Nov-2020
Date of Acceptance26-Nov-2020
Date of Web Publication13-Apr-2021

Correspondence Address:
Ahmed A Alahmari
Global Center of Mass Gatherings Medicine, Ministry of Health, P. O. Box 8320, 13314 Riyadh
Saudi Arabia
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jnsm.jnsm_107_20

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  Abstract 


Background: Although Saudi Arabia harbors a large number of confirmed cases with coronavirus disease 2019 (COVID-19), the Kingdom is characterized by a low case fatality rate, compared to that of other parts of the world. Patient-specific factors can play a role in this observation. Thus, we conducted the present retrospective study to investigate the epidemiologic characteristics of all fatalities resulting from COVID-19 infection in Saudi Arabia as of April 27, 2020. Materials and Methods: The present study was a multicentric, retrospective study that retrieved the data of all confirmed COVID-19-related deaths in Saudi Arabia from March 2 to April 27, 2020. Only records of the cases who underwent reverse transcription-polymerase chain reaction laboratory tests to confirm the presence of COVID-19 were retrieved. The data of COVID-19 fatalities in Saudi Arabia were obtained from the Health Electronic Surveillance Network of the Ministry of Health. Results: Up to April 27, 2020, 147 cases of COVID-19-related deaths were reported in Saudi Arabia. Almost two-thirds of them were aged above 50 years and majority of them were male (83.7%). Health-care workers represented 3.1% of the dead cases (n = 4 cases). The vast majority of the cases were from Makkah (44.9%) and Madinah (21.8%). Among males, the number of Saudi cases was much lower than non-Saudi cases with 22 and 101 deaths, respectively. Over 80% of the included cases had reported signs and symptoms before death, mainly fever and cough. Out of the 129 cases who had available data regarding comorbidities, 104 cases (80.6%) had one or more comorbidities. The median (interquartile range [IQR]) time from the onset of symptoms till test result confirmation was 5.5 (5) days, while the median (IQR) time from sample collection till test result confirmation was 1 (2) day. On the other hand, the median time from symptom onset till hospitalization and that till death was 1 (3) and 7 (8) days, respectively. Conclusion: COVID-19 is a growing pandemic with unprecedented spread rate and profound impact on the health of specific subsets of affected patients. In the present report, we demonstrated that fatalities from COVID-19 in Saudi Arabia are more common in older age groups, male patients, and non-Saudi residents. Besides, the presence of comorbidities is highly prevalent among fatalities from COVID-19 in Saudi Arabia. The Saudi health-care system has the advantage of fast-track diagnosis, which, in return, could have contributed to the low case fatality rate observed in the Kingdom. Further studies are required to identify the independent predictors of mortality for patients with COVID-19.

Keywords: Coronavirus disease 2019, epidemiology, mortality, Saudi Arabia


How to cite this article:
Alahmari AA, Alowais J, Khan AA. Epidemiological and clinical characteristics of fatalities from COVID-19 in Saudi Arabia: A multicentric, retrospective study. J Nat Sci Med 2021;4:124-9

How to cite this URL:
Alahmari AA, Alowais J, Khan AA. Epidemiological and clinical characteristics of fatalities from COVID-19 in Saudi Arabia: A multicentric, retrospective study. J Nat Sci Med [serial online] 2021 [cited 2021 Jun 13];4:124-9. Available from: https://www.jnsmonline.org/text.asp?2021/4/2/124/313637




  Introduction Top


The coronavirus disease 2019 (COVID-19) pandemic represents one of the greatest global health crises affecting 215 countries in various regions of the world and it has caused nearly 669,000 deaths worldwide.[1] Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), the causative agent of COVID-19, has thought to be initially transmitted to humans from bats in Huanan wholesale seafood market.[2] Currently, human-to-human transmission, by respiratory droplets, is the main route of the outbreak;[3] the published evidence highlights that the infection can be transmitted by both symptomatic and asymptomatic cases, leading to the dramatic spread of the outbreak within the community.[4] COVID-19 poses a critical socioeconomic challenge and threatens to collapse the health-care system in many countries by overwhelming the available health-care resources (such as ventilators and beds).[5]

The clinical presentation of COVID-19 varies widely from asymptomatic/mild symptoms to fatal disease course,[6] including acute respiratory distress syndrome (ARDS).[7] In the vast majority of cases, flu-like symptoms are usually present with a benign course and complete resolution.[8] Nonetheless, in a subset of the affected patients, severe alveolar cell damage and inflammatory process can occur, leading to overproduction of pro-inflammatory cytokines such as interleukin-6.[9] This cytokine storm can lead to ARDS, dysregulation in thermoreceptors, overproduction of lymphocytes, multiple organ failures, and eventually death.[10],[11],[12] Cardiac involvement has been reported in patients with COVID-19 as well.[13]

The current global mortality rate from COVID-19 is nearly 4% of the total cases.[1] Nevertheless, we can observe apparent inconsistencies in the spread of the virus and the course of the disease among the different regions affected, with wide variation in the mortality and case fatality rates.[14] While inadequate testing and low quality of health-care services were hypothesized as contributing factors for the reported low fatality rates during the pandemic,[15] initial reports from China suggest a potential impact of patient-specific factors on the outcome of COVID-19. Elderly patients; cases with comorbidities, such as diabetic and hypertensive care; and patients with immunosuppression seem to be more severely affected by COVID-19, with higher mortality rates in these subgroups.[16],[17] Predisposing genetic factors may play a role in determining an individual's susceptibility to infection and disease course as well.[18],[19] The different distributions of these variables among the affected countries may influence the mortality rates.

On March 2, 2020, the Ministry of Health (MOH) in Saudi Arabia has announced the first documented COVID-19 case in the Kingdom. Since then, the number of documented cases has increased to reach 278,835 cases by the end of July 2020. To date, a total of 2917 deaths were attributed to COVID-19 in the Kingdom, leading to a fatality rate of 1%.[20] We conducted the present retrospective study to investigate the epidemiologic characteristics of all fatalities resulting from COVID-19 infection in Saudi Arabia as of April 27, 2020.


  Materials and Methods Top


The present study was initiated after obtaining the protocol approval from the responsible ethics committees of MOH in the Kingdom of Saudi Arabia. We confirm that the present study did not violate any of the ethics principles declared by the latest version of the Declaration of Helsinki.[21] The preparation of the present manuscript run in compliance with the recommendations of the Strengthening the Reporting of Observational Studies in Epidemiology statement.[22]

Study design and population

Saudi Arabia is one of the Eastern Mediterranean Region (EMR) countries with a current population of nearly 35 million people.[23] Since the first documented case of COVID-19, the MOH developed a Health Electronic Surveillance Network (HESN) to document all suspected and confirmed cases of COVID-19 in Saudi Arabia. The present study was a multicentric, retrospective study that retrieved the HESN data of all confirmed COVID-19-related deaths in Saudi Arabia from March 2 to April 27, 2020. Only records of the cases who underwent reverse transcription-polymerase chain reaction laboratory tests to confirm the presence of COVID-19 were retrieved.

Data collection

The data of COVID-19 fatalities in Saudi Arabia were obtained from the HSEN. The extracted data included demographic characteristics (age, gender, nationality, region, occupation, and history of travel to endemic countries), patients' symptoms, presence of comorbidities, duration of symptoms before admission, time from hospitalization till death, time from symptoms until the confirmation of COVID-19, and time from sample collection until the confirmation of COVID-19. The data underwent thorough data management steps to ensure accuracy and validity. Each variable was checked for any typing or entry mistakes and bizarre or irrelevant observations.

Statistical analysis

The continuous variables were expressed as median with interquartile range (IQR), and the categorical variables were expressed as percentages (%). The graphical presentations were done using excel office worksheet, while the geographical presentation of the cases on a map was made using the Centers for Disease Control and Prevention Epi Info™ Version 7.2.3. 1. All median values, as well as their measures of variability, were formatted to one decimal place. All percentages were rounded to one decimal place. The analysis was done using IBM Corp. Released 2016. IBM SPSS Statistics for Windows, Version 24.0. Armonk, NY: IBM Corp.


  Results Top


A total of 26,740 residents of Saudi Arabia were tested positive for COVID-19 until April 27, 2020. Of them, 147 cases died and 23,602 cases had active disease with no definite outcome [Figure 1].
Figure 1: Patients' disposition flowchart

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Demographic characteristics

The highest percentages of fatalities were present among 50–59 years' age group (25.9%), 60–69 years' age group (21.1%), and 40–49 years' age group (17.7%). Notably, there were no reported deaths among patients aged less than 20 years, while that fatality rate was 2% among patients aged more than 90 years. The vast majority of patients were male (83.7%) and non-Saudis (74.8%). Health-care workers represented 3.1% of the fatalities (n = 4 cases). Of the 50 cases who had data regarding the history of travels, seven cases (14%) had a history of travel to endemic countries [Table 1]. Concerning the regional distribution of the fatality cases, the vast majority of the cases were from Makkah (44.9%), Madinah (21.8%), Jeddah (21.1%), and Eastern Region (4.8%), while Aseer, Jazan, and Tabuk harbored the least numbers of fatalities [0.7% each; [Figure 2]]. The distribution of fatalities was examined according to gender and nationality. Among males, the number of Saudi cases was much lower than non-Saudi cases with 22 and 101 deaths, respectively. This discrepancy was less in the female group, with Saudi females having a higher count of dead cases (15 vs. nine deaths among non-Saudi cases). The distribution of cases occurred in a similar pattern across all age categories, except for non-Saudi males in which the middle age group had a notably higher number of dead cases [Figure 3].
Table 1: Epidemiological features of coronavirus disease 2019 cases in Saudi Arabia

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Figure 2: Geographical distribution of coronavirus disease 2019 dead cases in Saudi Arabia

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Figure 3: Gender-wise and nation-wise distribution across age groups of coronavirus disease 2019 dead cases

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Clinical presentation

Over 80% of the included cases had reported signs and symptoms before death. The most commonly reported symptoms were fever (n = 87/108; 80.6%), cough (n = 85/108; 78.7%), difficulty breathing (n = 74/106; 69.8%), and sore throat [n = 14/105; 13.3%; [Figure 4]].
Figure 4: Symptoms reported earlier by coronavirus disease 2019dead cases

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Associated comorbidities

Out of the 129 cases who had available data regarding comorbidities, 104 cases (80.6%) had one or more comorbidities. The most commonly reported comorbidity was diabetes mellitus (n = 66/115; 57.4%), followed by cardiovascular disease (n = 23/116; 19.8%), hypertension (n = 22/116; 19%), chronic renal disease (n = 9/114; 7.9%), and cancer (n = 4/114; 3.5%). The data are presented in [Figure 5].
Figure 5: Distribution of comorbidities among all coronavirus disease 2019 dead cases

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Time variables

Time variables related to sample collection, test confirmation, hospitalization, and death are presented in [Figure 6]. The median (IQR) time from symptom onset till test result confirmation was 5.5 (5) days, whereas the median (IQR) time from sample collection till test result confirmation was 1 (2) day. On the other hand, the median time from symptom onset till hospitalization and death was 1 (3) and 7 (8) days, respectively.
Figure 6: Time variables of coronavirus disease 2019 cases

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  Discussion Top


In the past few months, the landscape of the COVID-19 pandemic has changed with a dramatic shift in the apex of the number of confirmed cases from China to the USA, Europe, and EMR. In the EMR, the number of confirmed cases rose sharply to reach 1,533,357 cases by the end of July 2020, with reported 39,661 deaths, leading to a mortality rate of 2.6%.[1] While Saudi Arabia is currently having the third-highest number of confirmed cases in the EMR after Iran and Pakistan, the case fatality rate is notably lower in Saudi Arabia, compared to that of other countries of the region.[1],[24] A growing evidence highlights that the different distributions of epidemiological characteristics among the affected countries may influence the mortality rates. Thus, in the present report, we described the characteristics of all fatalities resulting from COVID-19 infection in Saudi Arabia as of April 27, 2020.

Since the report of the initial clusters of COVID-19 cases, it was observed that older age groups are more vulnerable to infection and severe presentation, with higher fatality rates when compared to younger patients.[25] While it was initially unclear whether the difference between age groups reflects the lower risk of severe disease or lower susceptibility to infection, recent reports demonstrated that children under the age of 10 had similar susceptibility to older age groups,[26] which, in turn, highlights that the difference between age groups stems from the ability to fight the infection. Many authors proposed various pathogenic mechanisms behind the severe presentation in elderly population including age-dependent difficulty in removing particles from small airways,[27] low levels of angiotensin-converting enzyme 2 (ACE2) in the elderly,[28] incompetent immune response, excessive release of inflammatory mediators in the elderly – “inflamm-aging,”[29] and high frequency of comorbidities in the elderly population.[25] In the present report, we found that the incidence of mortality increased progressively with aging among COVID-19 patients in Saudi Arabia; more than two-thirds of the cases were older than 50 years and no fatalities were observed among cases younger than 20 years. To our knowledge, there are no currently published reports about the characteristics of COVID-19-related fatalities in Saudi Arabia. However, recent retrospective studies from Egypt,[30] Iran,[31] and Pakistan[32] demonstrated that older age groups were more susceptible to severe disease and death from COVID-19. This was in line with other reports from outside of EMR countries, such as China and the USA.[33],[34]

Recent surveillances demonstrated that male patients are more susceptible to severe COVID-19 infection and mortality;[35] this sex-specific difference was even observed in previous SARS outbreaks.[36] According to previous experiments, when combined with aging, males exhibited a lower level of ACE2,[37] less competent immune response,[38] and greater reduction in upper airway size than females.[39] Such factors could partly explain the higher susceptibility of severe infection among the male population. In our cohort, the male gender represented nearly 84% of the cases. Again, this was comparable to that of other reports from EMR countries.[30],[31],[32] In a previous systematic review, male patients had a three-fold increase in the risk of death from COVID-19, than female patients.[40]

Previous reports from the UK and the USA demonstrated that ethnicity might play a role in the course and outcome of COVID-19; both African-American and South Asian groups showed higher risks of intensive care admission, need for ventilation, and death than other ethnicities.[41] In a recent UK Biobank-based study, poor socioeconomic status was linked to a higher risk of severe COVID-19 infection among vulnerable ethnic groups.[42] This poor socioeconomic status can lead to less compliance with preventive measures and, hence, higher susceptibility of infection and severe disease.[43] The genetic variations in some of the key players in SARS-CoV infections, such as the MBL gene,[44] across different ethnicities, may be another explanatory factor for the ethnic-specific difference in the susceptibility to severe COVID-19 infection. In the present study, non-Saudi cases accounted for the vast majority of fatalities from COVID-19 in Saudi Arabia; it is well known that people from South Asia and India represent the majority of foreign workers in the Kingdom.[45] We observed that most of the cases were from regions in which the majority of non-Saudi residents live, such as Makkah and Jeddah. Our observation of the sex-specific difference in mortality between Saudi and non-Saudi cases can be explained by the fact that the majority of non-Saudi residents are actually males.[46]

It is widely established that comorbidities are major contributors to severe presentation and death in COVID-19 patients. For example, poorly controlled diabetes, with the subsequent deterioration in the body immune function, was found to significantly increase the risk of composite adverse outcomes, including death, among COVID-19 cases.[47] Likewise, malignancies and chronic renal diseases, alongside other immunocompromised conditions, were reported to be significant predictors of mortality in the setting of COVID-19.[48] The preexistence of cardiovascular or chronic lung diseases worsens the outcomes of COVID-19 as well.[49],[50] In our cohort, 80.6% had one or more comorbidities in the form of diabetes mellitus, cardiovascular diseases, hypertension, chronic renal disease, and cancer. The frequencies of comorbid conditions in the present study were comparable to that of other cohorts from EMR.[30],[31],[32] In a large cohort from China, hypertension, diabetes, and chronic obstructive pulmonary diseases were prevalent among severe COVID-19 cases.[51] Patients with preexistent comorbidities, such as diabetes and cardiovascular diseases, were more likely to suffer from severe disease in another report of COVID-19 cases.[16]

To that end, we observe that the epidemiological characteristics of COVID-19-related fatalities in Saudi Arabia are comparable to those of other countries of the region, as well as to those of other parts of the world. Thus, we can assume that the disparity in mortality rates between Saudi Arabia and other EMR countries stems from the difference in health-care systems, rather than from the peculiar epidemiological and clinical characteristics of the residents of the Kingdom. Alongside strict preventive measures taken by the Kingdom' authorities, Saudi Arabia took major steps to improve early discovery of the cases and the outcome of COVID-19.[52] For example, Saudi authorities implemented a health informatics tools to enable people who suspect to have COVID-19 to directly book appointments at dedicated COVID-19 clinics and drive-through mass testing locations around the Kingdom.[53] Massive screening was also hypothesized to discover asymptomatic cases who would not be discovered otherwise, which was reflected in the mortality rate within the Kingdom. In the present study, we found that the health-care facilities in Saudi Arabia take a median of only 1 day from sample collection to confirmation of the diagnosis of COVID-19, which reflects a fast-track diagnosis in confirmation of the suspected cases. Besides, the median time from symptom onset shown until hospitalization was only 1 day, which also indicates that seeking health care is fast in the KSA.

This is one of the first reports about the epidemiological and clinical characteristics of fatalities from COVID-19 in Saudi Arabia. However, we acknowledge that the present study had some limitations. The lack of enough data about alive COVID-19 cases in Saudi Arabia during the same study period restricted us to perform a proper analytical approach to identify potential predictors of COVID-19-related mortality in Saudi Arabia. In addition, data of the present study were collected retrospectively with many potential biases, such as case ascertainment bias. Most of the patient variables were self-reported, which could not be verified, with lack of much important clinical information.


  Conclusion Top


COVID-19 is a growing pandemic with unprecedented spread rate and profound impact on the health of specific subsets of affected patients. In the present report, we demonstrated that fatalities from COVID-19 in Saudi Arabia are more common in older age groups, male patients, and non-Saudi residents. Besides, the presence of comorbidities is highly prevalent among fatalities from COVID-19 in Saudi Arabia. The Saudi health-care system has the advantage of fast-track diagnosis, which, in turn, could have contributed to the low case fatality rate observed in the Kingdom. Further studies are required to identify independent predictors of mortality for patients with COVID-19.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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