We identified 425 medical records of patients with TBI that met the inclusion criteria. Among these, 43 patients died during hospitalization, and 23 records lacked a telephone number. Of the 359 records retained, 234 patients were managed at HCY (65.2%) and 125 at HGY (34.8%). Fifty-seven (57) phone numbers could not be reached (calls and SMS with no response). Among the 302 individuals contacted, there were 13 incorrect respondents and 9 patients who had died during long-term follow-up.

Among the 280 patients reached, we evaluated 114 patients, of whom 2 were excluded due to aphasia. The final study population consisted of 112 patients, including 74 (66.1%) from HCY and 38 (33.9%) from HGY. Figure 1 presents the patient flow diagram.

Figure 1. Flow diagram.

A total of 112 patients were included, with a median age of 36 (27 - 47) years (range 18 - 65). The 18 - 29 age group was represented by 36.6%. Males were more commonly represented, with a frequency of 90.2% and a sex ratio of 9.2:1.

In terms of occupation, 82.1% of the participants had a paid job prior to the trauma and 15.2% were pupils or students. We counted 70.5% of participants with primary or secondary education (Table 1).

Only 25.0% were treated within the first 6 hours. Half the patients (48.2%) were admitted to hospital more than 24 hours after the trauma. Road traffic accidents (RTAs) were the main cause of injury (57.1%), followed by assaults (23.2%). Motorbikes were involved in 76.6% of road accidents. The median Glasgow score was 12 (10 - 13), (range 5 to 15). TBI was moderate in 60.7% of cases. The median duration of coma was 3 (0 - 5) days, (range 0 to 34 days), with 37.5% of patients in coma for more than 3 days. Isolated TCE occurred in 64.3% of cases. The most frequently associated traumatic injury was facial in 17.9% of cases.

The brain scan perform rate was 97.3%. Lesions were found in 92.0% of cases, 61.1% of which were hemorrhagic, dominated by parenchymal contusions (21.3%) and 30.8% were bony.

More than half the participants (58.0%) underwent surgery. Craniotomy (40.0%) was the main type of operation, with extradural hematoma the dominant indication (35.4%). The median length of hospitalization was 10 (8 - 14) days (range 3 to 56). At discharge, 35.7% of participants had sequelae (Table 1).

The median time between the trauma and the assessment was 19 (14 - 26) months (range 13 to 40). Two-thirds (68.8%) of the patients had persistent long-term complaints of which we identified six types: headaches, forgetfulness, asthenia, motor deficit, epileptic seizures and deafness. The proportion of forgetfulness was 39.8%. among the participants, 21.3% had not returned to their previous job and 3.7% had changed jobs (Table 1).

Table 1. Population characteristics.

Data are in n (%) or median (quartiles: Q25 - Q75). *TBI = Traumatic brain injury.

Cognitive decline was assessed in each participant using 4 tests. The cognitive functions assessed were: visuospatial and executive functions, naming, memory, attention, language, calculation, abstraction, orientation, constructive praxis, motor speed and psychomotor speed. The overall prevalence of cognitive disorders was 58.0%. The frequency was 44.6% with the MoCA, 33.0% with the MMSE, 29.5% with the IHDS and 42.9% for the 5 Dubois words. Most of the patient hat a mild cognitive impairment. Figure 2 shows levels of cognitive disorders.

Bivariate analysis showed that age, return to work, level of education, Glasgow coma score, duration of coma, type of management and sequelae were significantly associated with cognitive disorders (p-value < 0.05). Multivariate analysis showed that primary education (OR=3.590; CI_95% [1.098 - 11.731]; p = 0.034), secondary education (OR=2.784; CI_95% [1.157 - 6.701]; p = 0.022), coma lasting more than 3 days (OR=2.984; CI_95% [1.298 - 6.859]; p = 0.010) and the presence of sequelae (OR=4.727; CI_95% [1.916 - 11.660]; p = 0.001) increased the risk of cognitive disorders. In addition, surgical management (OR=0.438; CI_95% [0.198 - 0.966]; P = 0.041) was a protective factor (Table 2).

(a)

(b)

Figure 2. Levels of cognitive disorders. (a). MoCA (Montreal Cognitive Assessment) and MMSE (Mini-Mental State Examination); (b). IHDS (International HIV Dementia Scale) and Dubois’ fives words.

Table 2.Multivariate analysis.

Our series consisted of 112 head trauma patients, with a median age of 36 years. Bello et al. found an average of 33 years [6], Thomas et al. 44 years [7]. The male predominance in our study is found in other authors such as Djientcheu et al (60%) [3] and Konaté et al (93%) [8]. The young male population is the most active and therefore the most at risk of trauma. Half of the victims were employed in the tertiary sector. This sector includes, in particular, transport, which, through RTAs, is the main circumstance in which TBIs occur. Ruet et al. reported a population dominated by blue-collar workers (48.1%) [9]. The level of education was primary or secondary in 70.5% of cases. Minoo et al. found that 64% of their population had a school education. A low level of schooling is a factor in the onset of cognitive problems after a head injury [10].

Only 25.0% were treated within the first 6 hours. Bello et al. documented that 35.0% of patients were attended to within 03 hours of the trauma [6]; all of our participants were transported by non-medical means, unlike the 45.7% who were transported by ambulance in Douala in 2011 [4]. The delay in treatment can be explained on the one hand by the poor functioning of our emergency medical assistance services and on the other by the fact that neurosurgery services are concentrated in major cities and take in trauma patients referred from other towns or even other regions of the country. Road accidents were the main cause of trauma. Motorbikes were involved in 76.6% of these. Transport by motorbike taxi is widespread in Cameroon, both in the cities and in rural areas, as it is in many other countries in the region. The trauma was moderate in 60% of cases, with a median coma duration of 3 days.

The brain scan showed lesions in 92% of cases, dominated by hemorrhagic lesions.

As a result, 58% of patients received surgical treatment. These results are similar to those found in the literature, with intracranial lesions being independent of the Glasgow coma score.

The median observation delay was 19 months, and two-thirds of patients had persistent long-term complaints, dominated by forgetfulness (40%) and headaches (20%). Failure to return to work was observed in 21% of patients. Bello etal. found 30% [6], Ruet et al. [9] 64% at one year. The latter study was carried out on a population of severe head trauma patients only.

Cognitive impairment was assessed in each participant using 4 tests for a global evaluation. The overall prevalence of cognitive disorders was 58.0%. Their frequency was 44.6% with the MoCA. Bello et al. found a prevalence of cognitive disorders of 40% using the MoCA [6]. Annoni et al. obtained a proportion of 60% of TCE patients with cognitive disorders, which had a major impact on the resumption of professional activities [11]. However, Bagirana et al. found 28.4% cognitive impairment in injured patients at 6 months (compared with 6.6% in controls) [12]. This could be explained by the broader spectrum of cognitive functions explored by our various tests.

The factors significantly associated with cognitive impairment in our population were primary education level (OR=3.590), secondary education level (OR=2.784), coma lasting more than 3 days (OR=2.984) and presence of sequelae (OR=4.727) at hospital discharge. In addition, surgical management (OR=0.438) was a protective factor. Bagirana et al. found a significant association between the severity of the initial trauma and cognitive disorders [12]; unlike Bello et al. who found no association between the type of cognitive disorders and the severity of the initial trauma [6]. Minoo et al. found severity of initial trauma and lack of school education to be significantly associated with cognitive impairment in adult brain injured patients [10].