Stroke represents a public health problem with a high mortality rate. In recent years, significant progress has been made in improving the diagnosis and treatment of stroke. In developing countries, with an epidemiological transition in terms of mortality, stroke passed to infectious diseases such as respiratory infections, diarrheal diseases, tuberculosis, HIV/AIDS, and malaria . In Congo, for a long time the diagnosis of stroke was based primarily on clinical grounds. The first CT scanner machines were installed in the early 2000s. We report the contribution brain CT scanner on the epidemiology and management of stroke in Brazzaville.
This is a retrospective study in Department of Neurology of the University Hospital of Brazzaville from 1 January 2006 to 31 December 2011. We included, all patients with the diagnosis of stroke performed by CT scan. The study variables were age, sex, type of stroke, the mortality rate, and the implementation of the CT scanner. Data were analyzed using epi-info 6 6·04dfr. The level of significance was set at P ≤ 0·05, logistic regression tests were used to compare variables between 2006 and 2011.
One thousand six hundred eight patients were included, representing a rate of 56·2% compared with all admissions, 57% (= 817) were male. The mean age was 61 ± 12·7 years (29–99 years), the mean mortality was 24·6 ± 3·8%.
Ischemic stroke was the most common, but its incidence has decreased from 85·6% in 2006 to 67·9% in 2011. The completion rate of the CT scan was 5·81% in 2006 against 93·68% in 2011. After multivariate analysis, between 2006 and 2011, there was a significant increase in cases of cerebral hemorrhage between 2006 and 2011 (OR: 5·21 CI 2·6 to 17·3; P < 0·0001), a decrease mortality (OR: 2·41 CI 1·4 to 8·2; P = 0,004) and a higher rate of completion of the CT scan (OR 15·4 CI: 8·2 to 29·4; P < 0,00001). A correlation was found between completion of CT scan and the frequency of hemorrhagic stroke and mortality rates (Fig. 1).
Brain imaging remains crucial for a correct management of stroke. The use of clinical scores such as the Siriraj stroke score and the WHO score in the determination of hemorrhagic or ischemic mechanism have shown their limitations in many studies . The incidence of hemorrhagic stroke is higher in African countries using brain CT scan, with frequency ranging from 21% to 60·1% compared with ischemic stroke . The increased rate of cerebral hemorrhage in our study can be explained partly by the fact that some small cerebral hematomas were clinically evoke ischemic stroke, and the advent of the CT scan has better defined the mechanisms of stroke as also reported Diagana et al.  in Nouakchott, and second, by a higher prevalence, contrasting with poor management of hypertension in Africa .
The routine use of CT scan has significantly changed the epidemiology and management of stroke in the Congo, the future opening of the MRI and stroke unit will be more beneficial.