We present this retrospective study that describes the clinical characteristics of 109 patients with COVID-19 admitted in EFSTH, a tertiary teaching Hospital in The Gambia. It provides additional insight into the risk factors for COVID-19 mortality in moderate to critically ill patients with COVID 19 associated pneumonia in resource limited countries. As in previous studies, our study has confirmed that age, co-morbidities especially Diabetes Mellitus as important prognostic factors associated with mortality in COVID 19 patients. We further report clinically important prognostic risk factors that are independently associated with mortality in our cohort: Hypoxemia (spo2 ≤ 93%) and patients referred from lower level health facilities.
The demographics of our patients were consistent with other studies. Males were more affected, and much older at presentation compared to females(7),(14). Most of our patients were also elderly with co-morbidities, hypertension and Diabetes mellitus being the most common(2),(15),(16),(17). As confirmed in other studies(3),(7),(18),(19), increasing age and Diabetes Mellitus were important prognostic factors associated with mortality in our patients. In contrast, 69.4% of deaths occurred at 60 years or older in our cohort as compared to 80%, or more in these other studies. This difference could be due to the very young age in West Africa(3),(10) (64% under the age of 24 years) compared to the develop world. Despite having a young population, the Gambia also has other risk factors similar to European countries ( 27% of Gambians have hypertension and 6% have diabetes) which further increases the risk of severe forms of COVID-19 and mortality(15).
The most commonly reported symptoms in our cohort were cough, dyspnea and fever at the time of presentation which is similar to other studies(20)(21)(22). However, fever was not the most common symptom at presentation. As already known, cough and dypsnea are the most common symptoms in the late phase of the disease which also coincides with the severe phase and also the onset of complications(23). This confirms the fact that most of the patients in our cohort presented late with either a severe disease or a complication of COVID 19.Therefore using a case definition requiring fever and at least one respiratory symptom may lead to an under diagnosis of a substantial proportion of patients with severe Covid 19(22) in The Gambia. Whether this finding in our cohort is due to the severity of the disease at presentation and/ or age of our patients, further research is needed to answer this question.
Most of our patients were referred from lower level health facilities. However, self referred patients had a better prognosis as compared to those referred from lower level health facilities. As already known, stigmatization negatively affects people in seeking and accessing health care(24)during pandemics. Study done in adult Gambian population also showed high level of worry and fear related to Covid-19(25). Further delay in lower level health facilities and the lack of critical care resources in these facilities could therefore result in worsening of patient’s condition before referring to a tertiary level. These important findings suggest that factors responsible for delay in referring patients in our lower level health facilities must be identified and addressed. As already stated in the 2012–2020 national health policy of The Gambia, some of the challenges of referring patients include inadequate number of ambulances, intermittent shortage of fuel, inadequate capacity to manage cases effectively, inadequate feedback mechanism, inadequate referral protocol and guidelines and late referrals especially at community level. Other factors that could have contributed to late referrals included the delay in receiving COVID 19 results from the central testing centre, and the non-availability of sample collectors in some health facilities.
Majority of our Patients presented with SPO2 of ≤ 93%. These patients were older, more likely to present with co-morbidities, respiratory features and more likely to be non-survivors. About 90% of the patients who died within 24 hrs also had Spo2 ≤ 93% and death within 24hrs was significantly associated with Spo2 ≤ 93%. On subgroup analysis, 70% of patients with 60 years or older who had increased risk for mortality had SPO2 of ≤ 93%. Despite supplemental oxygen, oxygen saturation of ≤ 93% was independently associated with death in our patients. Similar findings were found in other studies(26),(27) but at a lower level of oxygen saturation. This easily acquired clinical measure provides a more robust risk factor for fatal outcomes of patients with COVID 19 and thus should be part of our health system priority list. These findings of hypoxemia as an important prognostic factor for hospitalised patients with COVID 19 pneumonia in our cohort justifies the need to: 1) provide reliable supply of oxygen and its consumables (e.g. Nasal cannula, simple face mask, non-rebreathing mask), 2) set up and implement treatment guidelines on the use of oxygen, and 3) train health workers on the importance of oxygen therapy and modalities involved in giving oxygen.
Non survivors in our study were older, more likely to present with higher respiratory rate, lower oxygen saturation and Diabetes mellitus compared to survivors. This study confirms the fact that non-survivors were more likely to have severe disease and predictors of poor outcome(26). Approximately 35.8 % of our patients died of COVID 19. This is high when compared with patients admitted due to pneumonia (8.7–21%)(4),(5),(6) but is lower when compared with critically ill patients (49%)(7). The reason for this mortality may be that those who have a severe COVID 19 disease (54.7% in our study) are the ones likely to present to a tertiary health care facility as compared to the mild or asymptomatic cases. Majority of deaths occurred within 24hrs of admission and the median duration from admission to death is 1 day (1–18 days). The duration of hospital stay for non-survivors was similar to a study done in Nigeria(26) but much shorter compared to other studies(28). Death within 24 hrs was also significantly associated with lower oxygen saturation. This further confirms the need for supplemental oxygen as a first essential step for the treatment of patients with severe COVID-19 and should be a primary focus in The Gambia.
Further subgroup analysis, also indicates that mortality rate of patients referred from lower level heath facilities was higher (46 % vs 25%) as compared to self referred patients. This further confirms the fact that the lack of critical care resources, poor referral system and delay in COVID 19 testing in the lower level health facilities may have an impact on the outcome of COVID 19 patients in The Gambia.
This study has some limitations. First, as COVID 19 is a new disease and not much was known about the disease at the beginning of the pandemic, limited laboratory and radiologic investigations were done for our patients. Therefore, their role might be underestimated in predicting mortality. Secondly, Lack of effective antiviral, inadequate adherence to standard supportive therapy, and high-dose corticosteroid use might have also contributed to the poor clinical outcomes in some patients. Lastly, interpretation of our findings might be limited by the sample size. Even with its limitations, the results presented in this article are similar to the world literature but has found delay in primary and secondary health facilities as an important prognostic factor in low resource settings.