Aetiologies of altered states of consciousness: A prospective hospital-based study in a series of 464 patients of northern Tanzania

Neurological disorders in Northern Tanzania: A 6-year prospective hospital-based case series

Background

The burden of neurological disorders is large and altered by the HIV epidemic.

Objectives

We describe the pattern of neurological disorders and their association with HIV infection in adult patients attending a consultant hospital in Northern Tanzania.

Methods

In this prospective cross-sectional study, we collected data on adult neurological referrals over a 6-year period between 2007-13. The odds of HIV infection, across neurological categories adjusted for age and sex, was calculated.

Results

Of 2037 participants, 54.8% were male and 45.2% were female. The median age of participants was 43 years. The results for HIV screening were available for 992/2037 (48.7%) patients, of whom 306 (30.8%) were seropositive. The most frequent neurological disorders were cerebrovascular disease (19.9%), paraplegia (13.6%), and peripheral neuropathies (8%). Taken together CNS infection accounted for 278/2037 (13.6%). The adjusted odds (aOR) of HIV infection was highest amongst infections; brain abscesses (aOR 107, 95% CI 35.1-470.4) and meningitis/encephalitis (aOR 40.1, 95% CI 13.6-172.9), but also raised in cerebrovascular disease, paraplegia, peripheral neuropathies, cranial nerve palsies, seizures, cerebllar disorders, movement disorders, motor neuron disease and headache.

Conclusion

The main pattern of neurological disorders in Northern Tanzania is presented. The odds of HIV infection was highest in CNS infections and in a wide range of non-communicable neurological disorders.

Long-term consumption of virgin coconut (Cocos nucifera) oil diet impairs learning and memory in CD1 mice

Objective

Virgin coconut oil (VCO) has been used in the management of dementia in Alzheimer’s disease (AD). Therefore, this research investigated the effect of long-term consumption of VCO diet on learning and memory in CD1 mice.

Methods

Thirty male CD1 mice (divided into three groups, n = 10) were fed with standard rodent chow (control), 5% and 20% VCO diets (respectively) for 28 d. The Morris Water Maze (MWM) test was used to test the effect of VCO on visuo-spatial learning and memory, while the Novel Object Recognition Test (NORT) was used to measure short- and long-term recognition memory.

Results

Learning performance of mice did not differ in the MWM. During the probe trial, duration in the retention quadrant and annulus crossings were lower (P < 0.05) in the 5% and 20% VCO diet groups compared to the control diet group, showing that VCO impaired visuo-spatial memory. During the NORT, mice showed more total approaches in the 20% VCO diet group (P < 0.05) compared to control and the 5% VCO diet groups during the short-term memory test. During the long-term memory retention test, the total approaches were also higher in the 20% VCO group compared to control and 5% VCO group (P > 0.05). The discrimination index was also lower in the 20% VCO group compared to control and 5% VCO diet groups indicating impaired long-term cognitive memory in mice given 20% VCO diet. Histological examination of brains showed damage within the CA1 pyramidal cell layer of the hippocampus in the 20% VCO diet group, in line with the behavioural observations.

Conclusion

Long-term consumption of virgin coconut oil diet impairs memory in mice.

Clinical Spectrum, Etiology, and Outcome of Neurological Disorders in the Rural Hospital of Mosango, the Democratic Republic of Congo

There is little published information on the epidemiology of neurological disorders in rural Central Africa, although the burden is considered to be substantial. This study aimed to investigate the pattern, etiology, and outcome of neurological disorders in children > 5 years and adults admitted to the rural hospital of Mosango, province of Kwilu, Democratic Republic of Congo, with a focus on severe and treatable infections of the central nervous system (CNS). From September 2012 to January 2015, 351 consecutive patients hospitalized for recent and/or ongoing neurological disorder were prospectively evaluated by a neurologist, subjected to a set of reference diagnostic tests in blood or cerebrospinal fluid, and followed-up for 3–6 months after discharge. No neuroimaging was available. Severe headache (199, 56.7%), gait/walking disorders (97, 27.6%), epileptic seizure (87, 24.8%), and focal neurological deficit (86, 24.5%) were the predominant presentations, often in combination. Infections of the CNS were documented in 63 (17.9%) patients and mainly included bacterial meningitis and unspecified meningoencephalitis (33, 9.4%), second-stage human African trypanosomiasis (10, 2.8%), and human immunodeficiency virus (HIV)-related neurological disorders (10, 2.8%). Other focal/systemic infections with neurological manifestations were diagnosed in an additional 60 (17.1%) cases. The leading noncommunicable conditions were epilepsy (61, 17.3%), psychiatric disorders (56, 16.0%), and cerebrovascular accident (23, 6.6%). Overall fatality rate was 8.2% (29/351), but up to 23.8% for CNS infections. Sequelae were observed in 76 (21.6%) patients. Clinical presentations and etiologies of neurological disorders were very diverse in this rural Central African setting and caused considerable mortality and morbidity.

The prevalence and clinical manifestations of delirium in sub-Saharan Africa: a systematic review with inferences

BACKGROUND

In high-income countries with ageing populations, delirium is most prevalent in older adults and in palliative and intensive care settings. The prevalence and aetiology of delirium are likely to differ in low income countries, including sub-Saharan Africa (SSA), due to different population demographics, disease burden and exposure to pathogens. We reviewed published literature relating to the prevalence, clinical features and underlying causes of delirium in SSA and compare this with that published in high-income countries in order to identify knowledge and clinical service gaps, and priorities for further research.

METHODS

We performed a narrative review by comprehensively searching the following databases: Medline, PsychInfo, Embase and PubMed. Studies published between January 1 1975 and December 31 2013 in all languages, including the terms 'delirium', 'acute brain syndrome', 'organic brain syndrome', or 'acute confusion' originating from SSA were included. In addition, reference lists of included articles and online databases of African medical literature were hand-searched. We also included case series and case reports due to paucity of published studies.

RESULTS

We identified a total of 46 relevant studies. Delirium was the main focus of only one cross-sectional study, whereas most included delirium in studies on neuropsychiatric conditions. Only two studies reported prevalence in older adults. Most studies reported very low (<2%) delirium prevalence, whereas delirium in psychiatric inpatient and outpatient settings was higher than expected (18.2%-29.9%). Descriptive studies of 'bouffee delirante' from psychiatry settings were often describing delirium. Infection and HIV seropositivity were common associations of delirium throughout these studies. There were no studies of intensive, critical or surgical care settings or of management strategies.

CONCLUSIONS

We currently know very little about the prevalence, presentation and aetiology of delirium in developing countries. This knowledge gap should be tackled with some urgency, in order to address questions of screening, diagnosis, prevention and management in this setting.

Epidemiology of Dementia among the Elderly in Sub-Saharan Africa

Objectives. To review epidemiologic studies on the prevalence, incidence, and risk factors of dementia in sub-Saharan Africa (SSA). Methods. A MEDLINE search (from January 1992 to December 31, 2013) of epidemiologic studies, with no language restriction, was conducted using the keywords “dementia” or “Alzheimer's” and “Africa.” We selected for review population and hospital-based studies that reported the prevalence, incidence, or risk factors of dementia in SSA in people aged 60 years and above. References of selected articles were reviewed to identify additional relevant articles that met our selection criteria. Results. Of a total of 522 articles, 41 were selected and reviewed. The reported prevalence of dementia in SSA varied widely (range: 2.29%–21.60%); Alzheimer's disease was the most prevalent type of dementia. Only two studies conducted in Nigeria reported incidence data. Major risk factors identified include older age, female gender, cardiovascular disease, and illiteracy. Conclusion. Data on the epidemiology of dementia in SSA is limited. While earlier studies reported a lower prevalence of dementia in older persons, recent studies have put these findings into question suggesting that dementia prevalence rates in SSA in fact parallel data from Western countries.

Epilepsy in poor regions of the world

Epilepsy is a common disorder, particularly in poor areas of the world, and can have a devastating effect on people with the disorder and their families. The burden of epilepsy in low-income countries is more than twice that found in high-income countries, probably because the incidence of risk factors is higher. Many of these risk factors can be prevented with inexpensive interventions, but there are only a few studies that have assessed the effect of reducing risk factors on the burden of epilepsy. The mortality associated with epilepsy in low-income countries is substantially higher than in less impoverished countries and most deaths seem to be related to untreated epilepsy (eg, as a result of falls or status epilepticus), but the risk factors for death have not been adequately examined. Epilepsy is associated with substantial stigma in low-income countries, which acts as a barrier to patients accessing biomedical treatment and becoming integrated within society. Seizures can be controlled by inexpensive antiepileptic drugs, but the supply and quality of these drugs can be erratic in poor areas. The treatment gap for epilepsy is high (>60%) in deprived areas, but this could be reduced with low-cost interventions. The substantial burden of epilepsy in poor regions of the world can be reduced by preventing the risk factors, reducing stigma, improving access to biomedical diagnosis and treatment, and ensuring that there is a continuous supply of good quality antiepileptic drugs.