|ORIGINAL RESEARCH REPORT
|Year : 2023 | Volume
| Issue : 1 | Page : 15-21
Clinical characteristics and outcome of patients admitted during the first and second waves of COVID-19 pandemic at a Tertiary Hospital in Lagos, Nigeria
Iorhen Ephraim Akase1, Patricia Eyanya Akintan2, Erereoghor Otrofanowei1, Oluwarotimi Bolaji Olopade3, Gbenga Olorunfemi4, Adefolarin Opawoye3, Felix M Alakaloko5, Uyiekpen Emmanuel Ima-Edomwonyi3, Yeside Olubunmi Akinbolagbe2, Osigwe Paul Agabi1, Danladi Abraham Nmadu3, Gbemileke O Akinbode5, Aramide C Olasope3, Adewale Ogundare3, Abiola Bukunmi Bolarinwa6, Oluwakemi Elizabeth Awojumobi-Otokiti6, Precious J Enajeroh3, Moses Karami3, Christopher Imokhuede Esezobor3, Yewande O Oshodi7, Oluwole Ayodeji Ayotunde8, Wasiu Lanre Adeyemo9, Christopher O Bode10
1 Department of Medicine, College of Medicine, University of Lagos, Lagos, Nigeria
2 Department of Pediatrics, College of Medicine, University of Lagos, Lagos, Nigeria
3 Department of Medicine, Lagos University Teaching Hospital, Lagos, Nigeria
4 Division of Epidemiology and Biostatistics, University of Witwatersrand, Johannesburg, South Africa
5 Department of Surgery, Lagos University Teaching Hospital, Lagos, Nigeria
6 Department of Hematology and Blood Transfusion, Lagos University Teaching Hospital, Lagos, Nigeria
7 Department of Psychiatry, College of Medicine, University of Lagos, Lagos, Nigeria
8 Department of Obstetrics and Gynaecology, College of Medicine, University of Lagos, Lagos, Nigeria
9 Department of Oral and Maxillofacial Surgery, College of Medicine, University of Lagos, Lagos, Nigeria
10 Department of Surgery, College of Medicine, University of Lagos, Lagos, Nigeria
|Date of Submission||11-Jul-2022|
|Date of Acceptance||02-Jan-2023|
|Date of Web Publication||29-Mar-2023|
Dr. Iorhen Ephraim Akase
Department of Medicine, Infectious Diseases Unit, College of Medicine, University of Lagos, Lagos
Source of Support: None, Conflict of Interest: None
Introduction: Clinical data on the differences in presentation and outcome of admitted COVID-19 patients in Nigeria are limited. This study aimed to compare the first and second waves of the COVID-19 pandemic in a Tertiary Hospital in Lagos and describe the clinical differences between the waves, the severity of COVID-19, and the mortality differences. Methods: The study was a retrospective review of the medical records of all children and adults admitted to the Lagos University Teaching Hospital (LUTH) COVID-19 Isolation and Treatment Centre during the first wave (from April 2020 to October 2020) and second wave (from December 2020 to April 2021). The clinical characteristics (including COVID severity) and outcome among admitted patients during the two waves were compared. Results: Between April 2020 and April 2021, 602 patients were admitted to LUTH for COVID-19. Patients in the first wave were significantly younger (43 vs. 54.5 years), more in number (53.8% vs. 46.2%), and had a higher proportion of health-care workers than those in the second wave (14.5% vs. 6.5%). Comorbidities were present in more than half of the patients hospitalized for COVID-19 infection (51.0%). This proportion was much higher during the pandemic's second wave (41.7% vs. 61.9%, P < 0.001). The most common comorbidity found in hospitalized patients was hypertension (37.0%). Patients admitted during the second wave had shorter stays (11 vs. 7 days) and similar mortality rates (10.2% vs. 10.8%). Conclusion: The first and second waves had comparable mortality rates though patients in the first wave were younger and there were more healthcare providers in the cohort. Patients admitted to the second wave however had more comorbidities but shorter lengths of stay which may suggest a better understanding of the infection and better outcome.
Keywords: COVID-19, first wave, Lagos (Nigeria), second wave
|How to cite this article:|
Akase IE, Akintan PE, Otrofanowei E, Olopade OB, Olorunfemi G, Opawoye A, Alakaloko FM, Ima-Edomwonyi UE, Akinbolagbe YO, Agabi OP, Nmadu DA, Akinbode GO, Olasope AC, Ogundare A, Bolarinwa AB, Awojumobi-Otokiti OE, Enajeroh PJ, Karami M, Esezobor CI, Oshodi YO, Ayotunde OA, Adeyemo WL, Bode CO. Clinical characteristics and outcome of patients admitted during the first and second waves of COVID-19 pandemic at a Tertiary Hospital in Lagos, Nigeria. J Clin Sci 2023;20:15-21
|How to cite this URL:|
Akase IE, Akintan PE, Otrofanowei E, Olopade OB, Olorunfemi G, Opawoye A, Alakaloko FM, Ima-Edomwonyi UE, Akinbolagbe YO, Agabi OP, Nmadu DA, Akinbode GO, Olasope AC, Ogundare A, Bolarinwa AB, Awojumobi-Otokiti OE, Enajeroh PJ, Karami M, Esezobor CI, Oshodi YO, Ayotunde OA, Adeyemo WL, Bode CO. Clinical characteristics and outcome of patients admitted during the first and second waves of COVID-19 pandemic at a Tertiary Hospital in Lagos, Nigeria. J Clin Sci [serial online] 2023 [cited 2023 Jun 2];20:15-21. Available from: https://www.jcsjournal.org/text.asp?2023/20/1/15/372688
| Introduction|| |
The COVID-19 pandemic occurred in waves. The first wave of COVID-19 in Nigeria began in February 2020 and continued through October 2020, with the second wave spanning from December 2020 to April 2021. In addition, Nigeria has experienced two more COVID-19 outbreaks, the most recent of which lasted from December 2021 to February 2022.
Various SARS-CoV-2 subtypes were responsible for these waves. Different clinical manifestations are assumed to be caused by the variations, with some being more severe than others., The wild-type SARS-CoV-2 virus was primarily responsible for the first wave worldwide (B.1 strain). The appearance of the alpha variant (lineage B.1.1.7), first found in the United Kingdom in September 2020, and the beta variant (lineage B.1.351), first identified in South Africa, sparked the second wave. The third wave was believed to be triggered by the appearance of the delta variant (lineage B.1.617.2), which was first detected in India and was thought to cause more severe COVID-19 and higher mortality than previously identified variants. In November 2021, the omicron variation (lineage B.1.1.529) was discovered in Botswana and South Africa.,,
In response to the many waves of COVID-19 infection, various countries developed evolving measures. In Nigeria, the major goal of the COVID-19 response during the first wave was to contain diagnosed COVID-19 infections and limit the spread of new infections in the community. As a result, all COVID-19-positive cases were placed in isolation centers. However, in the second wave, asymptomatic, mildly severe, and moderate COVID-19 patients were treated in the community, according to guidelines for home-based care, with only severe and critical infections being admitted to the hospital.,
In Nigeria, epidemiologic disparities between the first and second waves have been documented using country-level data. The second wave had higher test-positivity rates (20.8% vs. 18.2%), a higher mean age (37.67 vs. 33.57), a higher proportion of females (41.90% vs. 35.64%), and a higher proportion of asymptomatic patients at the time of testing than the first wave (79.7 vs. 74.93%). Clinical data on the differences in presentation and outcome of admitted COVID-19 patients in Nigeria, on the other hand, are limited.
This study aimed to examine the first and second waves of the COVID-19 pandemic in a tertiary hospital in Lagos, and describe the clinical differences between the waves, the severity of COVID-19, and the mortality differences.
| Methods|| |
The study was a retrospective study of the clinical characteristics and outcome of all children and adults admitted to the Lagos University Teaching Hospital (LUTH) COVID-19 Isolation and Treatment Centre from April 2020 to April 2021.
The study was conducted at LUTH COVID-19 Isolation and Treatment Centre which has a total of 96-bed spaces in three wards with a separate intensive care unit of four beds located in another building. The center which was set up in March 2020, admitted its first patient on the April 6th, 2020, and was one of the 5 designated COVID-19 isolation and treatment Centers in Lagos State. It is located inside LUTH and provided services for both children and adults. The LUTH COVID-19 Isolation and Treatment Centre is the only one in Lagos State that is located inside a multispecialist tertiary hospital. The hospital set up a COVID-19 response team. The team was made up of 3 pediatricians, 5 consultants in internal medicine, hematologist, and an anesthetist. This group also included 8 resident doctors from internal medicine, medical officers, pharmacists, and nurses. The treatment and Infection prevention and control (IPC) protocol was based on the NCDC guidelines.
The review involved all patients with COVID-19 admitted to the isolation and treatment center. These were both children and adults with positive real-time reverse transcriptase polymerase chain-confirmed SARS-CoV-2.
The sample size for this study was 602, which was determined by the number of patients admitted to the LUTH isolation ward between April 2020 and April 2021. The case notes for these patients were reviewed. The first wave lasted from April to October 2020, and the second wave extended from December 2020 to April 2021.
The medical record of each patient admitted for COVID-19 was reviewed at the end of hospitalization (discharge, left against medical advice, or death). Two members of the study team extracted the following information from the medical records using a case report form: the sociodemographic information; the clinical features at presentation and during hospitalization; underlying chronic medical conditions and preexisting chronic medications; hospital resource utilization or needs such as the need for oxygen therapy, mechanical ventilation and dialysis; duration of hospitalization; and outcome of hospitalization.
The primary study outcome was the in-hospital mortality rate among children and adults with COVID-19. Other outcomes included the clinical severity of COVID-19 among children and adults, the duration of hospitalization, and demand for hospital resources such as oxygen therapy and mechanical ventilation among children and adults with COVID-19.
The study was approved by the LUTH Health Research Ethics Committee. All extracted information bore no identifiers to the study participants; names of participants were replaced with study ID. Confidentiality was ensured by allowing access to de-identifiable extracted data to members of the study team who required access. Furthermore, the extracted information documented in the study pro forma was stored in a locked cabinet; electronic databases derived from the study were password-protected, with access restricted to only those members of the study team who required it.
Data were entered into an excel sheet and then transferred into the Statistical Package for Social Science (SPSS, IBM, Armonk, New York, USA) version 16 for analysis. Categorical variables were presented with frequency and percentages, while age and duration of admission were presented as the median and interquartile range (IQR). Line graphs were used to depict the monthly trends in the number of admissions. Categorical variables were compared among the two waves using the Pearson's Chi-square while continuous variables (age and duration of admission) were compared using the Mann–Whitney U-test. Two-tailed test of the hypothesis was assumed and P < 0.05 was taken as statistically significant level.
| Results|| |
Sociodemographic characteristics of study participants
In all, 602 patients were hospitalized at LUTH for COVID-19 between April 2020 and April 2021. Patients admitted during the first wave were more than those in the second wave (n = 328/602, 53.8% vs. 278/602, 46.2%). The median age of the participants was 47 years (IQR = 27 years), as indicated in [Table 1], with patients from the first wave being much younger than those from the second wave (43 [IQR = 27.8] years vs. 54.5 [IQR = 23.3] years). The proportion of men was more than the proportion of women in both waves, However, the proportion of men reduced in the second wave as compared to the first wave (n = 202, 62.3% for wave 1 vs. n = 150/278, 54.0% for wave 2, P = 0.037). Health-care workers (HCWs) made up about 10% of COVID-19 patients, with the first wave having more HCWs than the second wave (14.5% vs. 6.5%). The majority of the patients (32.1%) had completed secondary school or had received more education (29.1%).
|Table 1: Comparison of sociodemographic characteristics of patients by wave|
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There were two major peaks in case admissions seen in May 2020 and January 2021 and a significant dip in case admissions in November 2021 [Figure 1].
More than half of the patients hospitalized for COVID-19 infection (51.0%) had comorbidities [Table 2]. The proportion of comorbidities was lower in the first wave as compared with the second wave (61.9% vs. 41.7%, P < 0.001). Hypertension was the most prevalent comorbidity found in hospitalized patients (37.0%). Dementia, benign prostatic hypertrophy, renal transplant, glaucoma, cardiac arrhythmias, achalasia, atrial septal disease, gastroesophageal reflux disease, Hepatitis B infection, migraine, thyroid disease, seizure disorder, pulmonary tuberculosis, Parkinson's disease, spondylosis are among the other comorbidities seen in 7.9% of cases. In both waves, <5% of female patients hospitalized were pregnant.
|Table 2: Comparison of the clinical and social among patients admitted during waves|
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For all admitted cases, contact tracing of potential or confirmed COVID-19 infection exposure revealed unknown sources in a majority of patients (83.1%), with exposure to colleagues the most commonly reported known exposure (8.3%), as shown in [Table 3].
Cough was the most prevalent symptom among patients in both waves of the pandemic, affecting nearly one-third (30.2%) in the first wave and almost half of the patients (48.9%) in the second. About 76.5% of those hospitalized with cough in the first wave had a dry cough, whereas 23.5% produced phlegm. Similarly, 74.5% of those in the second wave experienced a dry cough. Rashes, leg edema, orthopnoea, parotid swelling, and urine frequency are some of the less prevalent signs and symptoms [Figure 2].
|Figure 2: Pattern of presentation of COVID-19 infection cases in Lagos University Teaching Hospital (percentage prevalence of symptoms)|
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Four hundred and ninety-six patients (82.5%) survived and were discharged; about 80.2% did not require oxygen supplementation, while 2.3% did. The overall case fatality rate was 10.5%; first and second COVID-19 waves had comparable mortality rates (10.2% vs. 10.8%). There was no statistically significant association between the waves and the outcomes [χ2 = 5.989, P = 0.200, [Table 4]].
As indicated in [Table 5], patients hospitalized during the first wave stayed on average longer than those admitted during the second wave (11 [IQR = 9] vs. 7 [IQR = 5] days, respectively).
| Discussion|| |
Between April 2020 and April 2021, 602 COVID-19 patients were admitted to the LUTH. Patients in the first wave were substantially younger, more numerous, and had a greater number of HCWs than those in the second wave. In addition, the second wave of patients had more comorbidities, a shorter duration of stay, but similar mortality rates to the first wave.
The higher mean average age of the patients in the second was consistent with the adjusted admission policy of the second wave of COVID-19., Even though people of all ages have a similar predisposition to COVID-19, older people more commonly present with more severe disease, warranting admission. Alterations in lung structure and muscular atrophy may cause age-related geriatric changes in physiologic performance, lung reserve, airway clearance, and defense barrier function. Our study showed a higher male-to-female ratio, a feature that has been reported in other studies elsewhere., Males have reported a greater number of infections among confirmed COVID-19 cases than females, resulting in a gender disparity in COVID-19 case mortality. This disparity is believed to be driven by gender-related behavior, physiological traits, and the interaction of sex hormones with the immune system.,
Another important demographic was the high proportion of HCWs that were admitted to this cohort. This was partly due to the higher risks of exposure associated with patient care, most of whom were providing care to patients at a time of inadequate personal protective equipment, and poor training on IPC. In addition, the heightened sense of awareness and index for suspicion meant more staff presented to the hospital for evaluation at the slightest suspicion. This was especially so in the first wave of the pandemic. The long-term effect of such infections acquired in the course of providing care is currently unknown, but the impact may span from fear induced by perceived vulnerability to infections, to psychological manifestations such as posttraumatic stress disorder, depression, anxiety, and chronic stress.,
In both waves, a significant proportion of admitted patients were unaware of the possible source of their infection because they had no contact with any known COVID-19 carrier. This finding has been reported elsewhere,, and it is most likely due to transmission from asymptomatic individuals at the time of contact. The official reported figures for the incidence of COVID-19 infections in most African countries were under-estimated, with a modeling study projecting that only 14.2% of infections were diagnosed, indicating a large pool of undiagnosed infections within communities acting as reservoirs of the infection.
Fever was more commonly reported among patients admitted during the second wave. This was consistent with the different admission criteria used during the different waves, with patients in the second wave more likely to be admitted for clinical reasons rather than public health concerns. A greater proportion of patients admitted during the second wave presented more frequently with cough and fatigue, but with almost similar patterns for most other symptoms, including shortness of breath. This is in keeping with the poorly predictive value of clinical symptoms in making the diagnosis of COVID-19, especially in the early stages. Patients presenting later in the course of illness are more likely to have complications and therefore are more commonly associated with shortness of breath, hypoxemia, and a higher risk of death when these symptoms are found together.
Comorbidities have been identified as a significant contributor to severe COVID-19 infection. In the second wave, we admitted more people with comorbidities than in the first. This could be because of a change in admission requirements rather than the variant in circulation at the time., While it has been reported that the B.1.1.7 variant is associated with more severe disease than the Wuhan variant (which caused the first wave), it is difficult to say that this was the case here because our center was receiving referrals from other COVID-19 isolation facilities. As a result, the higher proportion of patients in the second wave appears to be due to the admission policy at the time rather than the virulence of the circulating variant. Other studies, like ours, have found that the most common co-morbidity among COVID-19 patients is hypertension., The link between COVID-19 and hypertension is not fully understood, but the fact that both illnesses are related to age may be a factor. Despite hypertension being found in the majority of COVID-19 patients, most studies have found diabetes mellitus to be more closely related to mortality than hypertension.,
Despite a decrease in the number of absolute admissions to our facility, the mortality rates were essentially the same across both waves. This finding must be interpreted in light of the higher number of infections recorded in the society, which appears to imply that the COVID-19 mortality rate in Nigeria was less severe than that of the first wave. This is consistent with findings in Europe and China,,, but not with findings in South Africa, where the second wave was associated with more COVID-19 infections, higher admission rates, and higher in-hospital mortality. It has been hypothesized that higher mortality rates were closely related to the number of admissions per time, as well as the resources dedicated to the care of patients admitted with COVID-19. Thus it appears that the ability of most facilities, including ours, to keep mortality rates at the same level, if not lower, may be due to more experience with the management of patients with COVID-19, as well as better preparedness compared to the first wave, which was associated with inadequate preparedness in many facilities and scientific uncertainty surrounding COVID-19., This may also explain the shorter duration of admission in our facility during the second wave, which was driven in part by a change in discharge policy from using two negative polymerase chain reaction tests during the first wave to the resolution of clinical symptoms in the second wave, a position derived from increased experience managing COVID-19 patients locally and globally.
| Conclusion|| |
The first and second waves had comparable mortality rates though patients in the first wave were younger and there were more healthcare providers in the cohort. Patients admitted to the second wave however had more comorbidities but shorter lengths of stay which may suggest a better understanding of the infection and better outcome.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]