The prevalence of traumatic brain injury among trauma patients in Ethiopia: systematic review and meta-analysis
Semagn Mekonnen Abate1, Bedru Jemal Abafita1, Tesfanew Bekele2
1Department of Anesthesiology, College of Health Sciences and Medicine, Dilla University, Dilla Ethiopia
2Department of Surgery, College of Health Sciences and Medicine, Dilla University, Dilla Ethiopia
Semagn Mekonnen Abate, Department of Anesthesiology, College of Health Sciences and Medicine, Dilla University, Dilla Ethiopia.
Background: Traumatic Brain Injury is the common cause of mortality and disability in the young age populations particularly in children and adolescents. The objective of this systematic review and meta-analysis was to assess the prevalence of Traumatic Brain Injury among trauma patients in Ethiopia. Methods: A three-stage search strategy was conducted on PubMed/Medline, Science direct and African Online Journal and a grey literature search were conducted on Google scholars. The data analysis was conducted with R software version 3.6.1. Results: The pooled prevalence of Traumatic Brain Injury in Ethiopia was 20% (95% confidence interval, 11 to 32). Subgroup analysis revealed that Road Traffic Accident was the commonest mechanism of injury in Ethiopia 21% (95% confidence Interval (IC), 15 to 30 followed by Assault 18% (95% confidence interval, 5 to 48). Conclusion: The review revealed that the prevalence of Traumatic Brain Injury among trauma patients in Ethiopia is high as compared to continental and global reports. The policymakers and stakeholders should work on regulatory laws on transportation and pre-hospital emergency medical care system is also highly in demand.
Registration: This review was registered in Prospero international prospective register of systematic reviews (CRD42020146643).
Keywords: Head injury, Road Traffic Accident, Assault, Ethiopia.
Ann Afr Surg. ****; **(*):***
Conflicts of Interest: None
© 2020 Author. This work is licensed under the Creative Commons Attribution 4.0 International License.
Head injury is defined as any trauma to the head resulting from the external mechanical force, such as rapid acceleration or deceleration, impact or penetration (1). Centers for Disease Control and Prevention (CDC) defines Traumatic Brain Injury (TBI) as a disruption in the normal function of the brain that can be caused by a bump, blow, or jolt to the head or a penetrating head injury (2).
Head injury is the common cause of mortality and disability in the young age population particularly in children and adolescents (1). Head injury is considered the greatest contributor to death and disability globally among all trauma-related injuries (3). In addition to the impact of TBI on the individual, TBI can negatively affect families, communities, and the economy of the country through the loss of productive age groups and treatment costs (4).
It is estimated that in the USA, around 5.3 million people are living with a TBI related disability (5) and 7.7 million people in the European Union have experienced TBI have disabilities (6). The World Health Organization (WHO) estimates that each year more than 10 million people in the world sustain TBIs resulting in death or severe disability (7).
The global burden of disease study report shows that there were 27.08 million new cases of TBI in 2016. The report also revealed that TBI caused 8.1 million years of life lived with disability (YLD). In sub-Saharan Africa, there were 2.9 million new cases of TBI which was equivalent to 360 per 100,000 populations. The report also showed that Ethiopia accounted for 659(624-703) TBI cases per 100,000 population which was roughly representing 10.8% sub-Saharan Africa and 28% of Eastern sub-Saharan Africa Traumatic Brain injury cases (3).
The incidence of TBI globally is rising, mainly owing to injuries associated with increases in population density, the increased use of motor vehicles, particularly in middle-income and low-income countries (8). Globally, road traffic accidents are responsible for more than 50 million injuries every year, with about 1.2 million endings in death (3,9,10). Many TBIs are indeed the result of motor-related accidents, but the pattern of injury varies across regions: in high-income countries, individuals with TBI are generally motor-vehicle occupants, whereas in middle-income and low-income countries patients with TBI are often vulnerable road-traffic users such as pedestrians, cyclists, and motorcyclists. Increased motorization combined with inadequate traffic education and slow implementation of traffic safety regulations is the main cause of the increasing incidence of TBI in low-income and middle-income countries (11).
The prevalence of traumatic brain injury among trauma patients in Ethiopia varied from town to town. A study conducted at Addis Ababa emergency center, Tikur Anbessa specialized hospital showed that among 204 head injury patients enrolled in the study, forty-one percent (41%) of injuries occurred from a road traffic accident and 21 patients died (10.3%) (12). Another study in myungsun Christian medical center reveals that the prevalence of head injury among trauma patients visited the adult emergency department was 24.9% and road traffic accident was the leading cause of head injury (43.5%) followed by fall down accident 35.8% (13). A study done at Jimma university teaching hospital shows that the prevalence of head injury among patients admitted to adult ED was 3.69%. Interpersonal violence accounted for (54.1%) whereas road traffic accidents accounted for (31.1%) (14). Another study in Tikur Anbessa specialized hospital ED indicates that there was a 1.9% mortality rate out of 9956 patients who visited the emergency department. The most common cause of death was head injury (21.5%) (15). A study conducted Ayder referral hospital show that the prevalence of head injury from road traffic accident record review was 48.7%(16).
Another study conducted at Dilla university referral hospital shows the prevalence of head injury was 32.1% and road traffic accident was the main cause of head injury (17). A study at Gondar university referral hospital also reveals that the prevalence of head injury was 40.5%. Among this 46.7 % occurred due to interpersonal fight (18). A Study done in Ayder referral hospital showed that the prevalence of head injury was 56.3% and the most common causes of head injury were fallen down accident (41.9%), road traffic accident (24.9%), and interpersonal violence (24.8%) (19). In Ethiopia, there no national prevalence of head injury and the health planners and policymakers utilized demographic health surveys. The aim of the current study is therefore to assess the national prevalence of traumatic brain injury among trauma patients in Ethiopian.
Protocol and registration
The systematic review and meta-analysis was conducted based on the Preferred Reporting Items for Systematic and Meta-analysis (PRISMA) protocols. This systematic review and meta-analysis was registered in Prospero international prospective register of systematic reviews (PROSPERO identifier CRD42020146643)
Types of studies
All cross-sectional studies reporting the prevalence of Traumatic Brain Injury among trauma patients in Ethiopia without any date and language restriction were incorporated.
Types of participants
The participants were all trauma cases having a head and/or neck injury.
Outcomes of interest
The primary outcome of interest was the prevalence of Traumatic Brain Injury among trauma patients in Ethiopia. The risk factors Traumatic Brain Injury among trauma patients in Ethiopia in different regions of the country were secondary outcomes.
The review incorporates studies conducted in Ethiopian.
The review included all cross-sectional studies conducted to assess the magnitude of Traumatic Brain Injury and other cross-sectional studies conducted on pattern and outcomes of trauma that reports Traumatic Brain Injury as a secondary outcome.
Studies that didn’t report traumatic brain injury, randomized controlled trials, cohort and case-control studies, systemic reviews, and case reports and series were excluded.
The search strategy was intended to explore all available published and unpublished studies on Traumatic Brain Injury among trauma patients in Ethiopia without date and language restrictions. A three steps search strategy was employed in this review. An initial search on PubMed/Medline, Science direct and African Online Journal was carried out followed by an analysis of the text words contained in Title/Abstract and indexed terms. A second search was undertaken by combining free text words and indexed terms with Boolean operators. The third search was conducted with the reference lists of all identified reports and articles for additional studies. Finally, an additional and grey literature search was conducted on Google scholars up to ten pages. The search strategy conducted in PubMed was presented in appendix 1.
The data from each study were extracted with two independent authors with a customized format. The disagreements between the two independent authors were resolved by the other two authors. The extracted data includes Author names, date of publication, sample size, the prevalence of head injury among trauma patients, mean age of participants and risk factors of the trauma. Finally, the data were then imported for analysis in R software version 3.6.1.
Data analysis was carried out in R statistical software version 3.6.1with Meta and metafor packages. The pooled prevalence of traumatic brain injury was determined with a random effect model as there was substantial heterogeneity. The Heterogeneity among the included studies was checked with forest plot, χ2 test, I2 test, and the p-values. Substantial heterogeneity among the included studies was investigated with subgroup analysis. Publication bias was checked with a funnel plot and the objective diagnostic test was conducted with Egger's correlation, Begg's regression tests, and Trim and fill method. Furthermore, moderator analysis was carried out to identify the independent predictors of Traumatic Brain Injury among trauma patients. The results were presented based on the Preferred Reporting Items for Systemic Reviews and Meta-Analysis (PRISMA)(31), (appendix III).
Description of included studies
A total of 198 articles were identified from different databases as described in the methodology section with the Prisma flow diagram (Figure 1). Twenty-one articles were selected for evaluation after the successive screening. Twelve Articles with 14,017 participants reporting the prevalence of head injury as a primary outcome were included and the characteristics of each included studies were described in (Table 1) and the rest were excluded with reasons (Table 2). The included studies were published from 2011 to 2019 with sample size ranged from171 to 4153. The mean (SD) ages of the included studies varied from 24.7± 15.8 to 30.7±14 years.
Nine studies were conducted in the Oromia region (3), Addis Ababa (3) and SNNPR (3) whereas there were only two and one studies in Amhara and Tigray regional states respectively. However, there was no study reporting the magnitude of TBI in Somalia, Afar, Gambella, Benshangul Gumuz, and Dire Dawa City Administration. The five included studies assessed the prevalence and outcomes of Traumatic Brain Injury whereas the remaining seven studies were on pattern and outcomes of trauma and they reported Traumatic Brain Injury. The majority of included studies reported the prevalence of Traumatic Brain Injury alone and the rest reported the prevalence of head and neck injury. Two of the included studies used the total admission for calculation of prevalence and ten of the included studies used the total trauma cases as a source of population. Seven studies identified Road Traffic accident as the main mechanism of Traumatic Brain Injury followed by Assault whereas five studies reported Assault as the main mechanism of injury followed by Road Traffic accident.
Assessment of methodological quality
Articles identified for retrieval were assessed by two independent Authors for methodological quality before inclusion in the review using a standardized critical appraisal Tool adapted from the Joanna Briggs Institute (20) (Table 3). The disagreements between the Authors appraising the articles were resolved through discussion with the other Two Authors. Articles with average scores greater than fifty percent were included for data extraction.
Twelve studies reported Traumatic Brain Injury was included for Meta-analysis. The five studies were conducted on the prevalence of Traumatic Brain Injury whereas seven studies were conducted on patterns of Trauma but they included in the Meta-analysis because of the reported prevalence of Traumatic Brain Injury.
The pooled prevalence of Traumatic Brain Injury in Ethiopia was 20% (95% confidence interval (CI) 11 to 32 studies, and 12915 participants) (Figure 2).
Subgroup analysis with region showed that prevalence of Traumatic Brain Injury was the highest in Tigray regional state 49% (95% confidence Interval (IC), 43 to 54, one study, 322 participants) followed by Oromia regional state 20% (95% confidence Interval (IC), 3 to 66, three studies, 4972 participants) whereas the lowest was in Amhara regional state 15% (95% confidence Interval (IC), 3 to 53, two studies, 4413 participants) followed by Addis Ababa and Sothern Nations Nationalities people’s region (Figure 3).
Subgroup analysis with mechanism injury revealed that Road Traffic Accident was the highest mechanism of injury in Ethiopia 21% (95% confidence Interval (IC), 15 to 30, seven studies, 3530 participants). The subgroup analysis also revealed that Assault was the second cause of Traumatic Brain Injury in Ethiopia, 18% (95% confidence Interval (IC), 5 to 48, 5 studies, 9385participants) (Figure 4).
The funnel plot for evaluation of publication bias didn’t show asymmetric funnel plot (Figure5). Besides, the rank correlation and Egger’s regression test didn’t show a significant difference for small study effect (p-value >0.05). Moderator analysis failed to identify the effects of study quality, mean age of participants, year of publication and sample size on effect estimate of Traumatic Brain injury among trauma patients, p-value >0.05.
The pooled prevalence of Traumatic Brain Injury in Ethiopia was 20% (95% Confidence Interval (CI), 11 to 32). The finding of this review is in line with a systemic review conducted in the Sub-Saharan African region. The similarity may be explained by relatively similar socio-economic status, mode of transportation, and infrastructure within these regions (30).
Global report on Traumatic Brain Injury revealed that the prevalence of Traumatic Brain Injury was very low in the USA, China, Norway, and Finland when compared to this systemic review. The possible explanation for this discrepancy might be due to road safety protocols, better infrastructure, and community awareness towards possible risk factors of injury including violence, driving speed, substance abuse and use of safety belts.
This systemic review revealed that personal violence/Assault was the second most common cause of Traumatic Brain Injury in Ethiopia. However, personal violence was the least mentioned cause of Traumatic Brain Injury as depicted with other systemic reviews conducted in the Sub-Saharan region and global set up (3, 28,30). This discrepancy might be due to the current tribalism and instability in the Ethiopian context.
The systemic review revealed that Road Traffic Accident was the most common cause of Traumatic Brain Injury which is in line with another systemic review conducted in the Sub-Saharan region. The similarity may be explained by a similar mode of transportation, socioeconomic status, transportation and principles of road safety (30).
The subgroup analysis revealed that the prevalence of Traumatic Brain Injury in Ethiopia was higher in Tigray regional state as compared to other regional states. This discrepancy might be due to a few studies, only one study on the prevalence of traumatic brain injury in this region, study setting and small sample size.
Limitation of the study
The review incorporated a few studies assessing the prevalence of Traumatic Brain Injury among trauma patients. Besides, there were a small number of studies in some regions and there were no studies at all in some regions assessing the prevalence of traumatic brain injury. As a result, the review had substantial heterogeneity. The methodological qualities of the included studies were high to moderate as depicted with the methodological assessment tool. However, the overall quality of evidence was low because there was an inconsistency effect estimate within studies and also it is a meta-analysis of cross-sectional studies (low levels of evidence).
The review revealed that the prevalence of Traumatic Brain Injury among trauma patients in Ethiopia is high when it is compared with continental and global reports. Road Traffic Accident and Assault were the most common causes of traumatic brain injury in Ethiopia. Therefore, interventions aiming at reducing the prevalence of Traumatic Brain Injury through awareness creation strategies on road safety, regulatory laws on transportation, mode of transport, types of vehicles, and driving license. Besides, the policymakers and stakeholders should work on awareness creation strategies on road safety, regulatory laws on transportation, mode of transport, types of vehicles, driving license, and pre-hospital emergency medical care system are highly in demand to reduce the prevalence of Traumatic Brain Injury in Ethiopia. Further evidence on the prevalence of Traumatic Brain Injury and associated factors from each region with a large sample size is still in demand.
Ethics approval and consent to participate
Ethical clearance and approval were obtained from the ethical review board of the College of Health Science and Medicine.
Consent for publication
Availability of data and materials
Data and material can be available where appropriate.
The authors declare that there are no competing interests
No funding was obtained from any organization
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