Tropical ataxic neuropathy: Findings of a neuroepidemiological survey of Odeda, southwest Nigeria.

BACKGROUND: Tropical ataxic neuropathy seems to have dwindled in public health importance in Nigeria despite the high consumption of cassava-based meals by a huge proportion of people in local Nigerian communities. Yet a recent report suggest its persistence in the same ethnogeographic setting where it was first reported in Nigeria. Our objective was to investigate the prevalence of tropical ataxic neuropathy in Odeda, Ogun state, southwest Nigeria inhabited by a different ethnic group compared to Epe where the disease was first described. METHODS: A two-stage, cross-sectional survey of Odeda local government area for the prevalence and profile of toxiconutritional neurological disorders was carried out between May and June 2015. A screening instrument was applied by trained non - medical interviewers with positive responders further evaluated by a neurologist. RESULTS: 2392 individuals aged 18 years or older were screened and had a mean age of 37.2 ±â€¯16.1 years, were predominantly of Egba Yoruba ethnicity. Thirty nine cases of tropical ataxic neuropathy were diagnosed and crude prevalence rate was 16.3/1000 (95% CI 11.2-21.4/1000). Older age and rural residence were associated with higher prevalence. Distal sensory polyneuropathy was the most common feature whereas sensorineural deafness was the least common finding. CONCLUSION: This report provides evidence that tropical ataxic neuropathy persists and in a wider geographic spread. Thus tropical ataxic neuropathy still remains a significant public health importance and concerted efforts are required to mitigate or eradicate tropical ataxic neuropathy in southwest Nigeria and other regions of Africa affected by cassava- related toxiconutritional disorders.

Epidemiology of active epilepsy in a suburban community in Southeast Nigeria: A door-to-door survey.

CONTEXT: Epilepsy is one of the most common neurologic conditions afflicting an estimated 65 million people the world over. Current community-based data on the prevalence of active epilepsy in Africa are sparse. AIMS: This study was aimed at determining the prevalence and profile of active epilepsy in a suburban community in Southeast Nigeria. METHODS: It was a two phase cross-sectional descriptive study. In the first phase, those with possible active epilepsy were identified in a door-to-door survey using a modification of the World Health Organization Neuroscience research protocol. In the second phase, cases of active epilepsy were identified and the clinical forms of epilepsy diagnosed based on the International League against Epilepsy guidelines 1993. RESULTS: A total of 6,800 persons was screened in the first phase of the study. There were 29 cases (16 males and 13 females) of active epilepsy. The point prevalence of active epilepsy was 4.3/1,000 (95% confidence interval (95% CI): 2.7-5.9) for the total population, 4.9/1,000 (95% CI: 2.5-7.3) for males and 3.7/1,000 (95% CI: 1.7-5.7) for females. The age-adjusted prevalence for the total population was 4.1/1,000 (US Population 2000). Classified using clinical criteria only, generalized seizures occurred in 62.1% (n=18) while partial seizures occurred in 37.9% (n=11) of cases. CONCLUSIONS: The prevalence of active epilepsy in Southeast Nigeria is comparable to that found in developed and some developing countries but less than that reported in suburban Southwest Nigeria about three decades ago.

Illness concept among people with epilepsy and their caregivers and preferred treatment methods in a suburban community in Southeast Nigeria.

BACKGROUND: Epilepsy, one of the world's most prevalent chronic diseases is still regarded as a supernatural disease in many parts of the world. These superstitious and cultural beliefs tend to influence treatment seeking behavior of people living with epilepsy (PWE) and their caregivers. STUDY DESIGN: People living with epilepsy in a semi-urban community in Southeast Nigeria were identified in a two phase door-to-door cross-sectional descriptive study. Those identified and their caregivers were further interviewed to determine their concepts of the disease, their treatment (actual and preferred) and what informed treatment. RESULTS: We found 29 cases of active epilepsy, 16 (55.2%) males and 13 (44.8%) females. Witchcraft was held as a major cause of epilepsy in the community accounting for 36.2% (n=17) of the responses. The three major treatment modalities used were spiritual (healing churches), traditional (herbal medicines) and orthodox treatment with antiepileptic drugs. Spiritual treatment was the preferred treatment modality, though most (89.7%) have used traditional (herbal medicine) treatment at one point in the course of the disease. Beliefs on epilepsy and information on the disease obtained mostly from non-medical sources informed treatment. CONCLUSION: The epileptic population studied preferred spiritual treatment though use of traditional treatment was also common. Treatment seeking behavior was greatly influenced by their beliefs and information on the disease obtained mainly from non-medical sources.

Epilepsy treatment gap: prevalence and associated factors in Southeast Nigeria.

OBJECTIVES: The treatment gap of epilepsy in developing countries is high, and data on the magnitude and causes of epilepsy treatment gap in Africa are sparse. We aimed to determine the prevalence and causes of epilepsy treatment gap among people with epilepsy in a Suburban community in Southeast Nigeria. MATERIALS AND METHODS: The direct method was used to determine epilepsy treatment gap in a two-phase cross-sectional study. Those with probable epilepsy were identified in a door-to-door survey using a modification of World Health Organization (WHO) protocol in the first phase. In the second phase, an epilepsy-specific questionnaire that was further designed to determine the magnitude and causes of epilepsy treatment gap was used. RESULTS: The overall treatment gap of epilepsy was 76% (n = 22/29). The major contributors to the overall treatment gap were people who were never diagnosed accounting for a diagnostic gap of 38% (n = 11/29) and those who were diagnosed but discontinued antiepileptic drug (AED) treatment of their own volition accounting for a therapeutic gap of 38% (n = 11/29). CONCLUSIONS: Epilepsy treatment gap in Southeast Nigeria is comparable to that in many developing countries. Fifty percent of the overall treatment gap was caused by patients discontinuing AED treatment of their own volition despite continuing fits. This result may indicate that perhaps with appropriate education on the need to adhere to therapy, the treatment gap in the community may be narrowed.

Nutritional status of older persons presenting in a primary care clinic in Nigeria.

The study objective was to determine the nutritional status and its association with sociodemographic characteristics and health complaints of older persons presenting at the General Outpatients Department (GOPD) Clinic of University College Hospital (UCH), Ibadan, Nigeria. A cross-sectional descriptive design was used to select 500 consecutively presenting participants aged 60 years and older between September and December, 2009. The Mini-Nutritional Assessment (MNA) tool and body mass index were used to assess undernutrition and overweight, respectively. The prevalence of nutritional problems was 61.9% (undernutrition = 7.8% and overweight = 54.1%). Being unmarried (P < 0.001), engagement in a job after the age of 60 years (P < 0.001), constipation (P = 0.009), rectal bleeding (P = 0.008), and oral problems (mouth, teeth, and tongue) were significantly (P < 0.001) associated with undernutrition. Younger age (P = 0.050) and female gender (P = 0.011) were significantly associated with being overweight. Logistic regression analysis showed being unmarried OR = 1.355 (95%CI 1.075-1.708) to be the most important factor for the development of undernutrition. The high prevalence of nutritional problems in this study underscores the need for intervention in this population. Correlation analysis (Pearson's) showed a positive association between BMI and MNA scores (r = 0.152, P = 0.001).

Prevalence of cognitive impairment: data from the Indianapolis Study of Health and Aging.

BACKGROUND: The epidemiology and natural history of cognitive impairment that is not dementia is important to the understanding of normal aging and dementia. OBJECTIVE: To determine the prevalence and outcome of cognitive impairment that is not dementia in an elderly African American population. METHOD: A two-phase, longitudinal study of aging and dementia. A total of 2212 community-dwelling African American residents of Indianapolis, IN, aged 65 and older were screened, and a subset (n = 351) received full clinical assessment and diagnosis. Subsets of the clinically assessed were seen again for clinical assessment and rediagnosis at 18 and 48 months. Weighted logistic regression was used to generate age-specific prevalence estimates. RESULTS: The overall rate of cognitive impairment among community-dwelling elderly was 23.4%. Age-specific rates indicate increasing prevalence with increasing age: 19.2% for ages 65 to 74 years, 27.6% for ages 75 to 84 years, and 38.0% for ages 85+ years. The most frequent cause of cognitive impairment was medically unexplained memory loss with a community prevalence of 12.5%, followed by medical illness-associated cognitive impairment (4.0% prevalence), stroke (3.6% prevalence), and alcohol abuse (1.5% prevalence). At 18-month follow-up, 26% (17/66) of the subjects had become demented. CONCLUSIONS: Cognitive impairment short of dementia affects nearly one in four community-dwelling elders and is a major risk factor for later development of dementia.

Cognitive function in Nigerians with newly diagnosed epilepsy.

OBJECTIVE: The objective of this study was to evaluate the pattern of cognitive disturbances in Nigerian Africans with newly diagnosed epilepsy, prior to onset of drug therapy. METHODS: A total of 60 consecutive patients (mean age 31.6 +/- 17.4, range 14-55 years) presenting with a clinical diagnosis of epilepsy were recruited for the study. Sixty healthy volunteers without a history of epilepsy and who were age-, sex- and level of education matched with the epileptic patients, were recruited as controls. The administration of cognitive tests was done with the FePsy computerized neuropsychological test battery. The tests administered were the visual and auditory reaction times, the continuous performance test and the recognition memory tests to assess mental speed, attention and memory respectively. The means of the cognitive performances of the epileptic patients and controls were statistically compared. RESULTS: Epileptic patients performed worse than the controls across the spectrum of cognitive tasks assessed (P = 0.00001; P < 0.025), with the exception of the beta parameter (response bias) of the vigilance test (P = 0.488; P > 0.025). CONCLUSIONS: The cognitive impairments of short-term memory, psychomotor speed and sustained attention observed in this study are similar to those reported in the literature for patients with epilepsy. The results of this study will be useful in the counseling of patients on their educational, social and vocational needs.

Community screening interview for dementia (CSI 'D'); performance in five disparate study sites.

The Community Screening Interview for Dementia (CSI 'D') was developed as a screening instrument for dementia for use in cross-cultural studies. It consists of two components, a cognitive test for non-literate and literate populations and an informant interview regarding performance in everyday living. The development of the CSI 'D', involving harmonization, translation, back translation and pilot testing, for use in five sites is described. The results demonstrate the adaptability and utility of the CSI 'D' in populations from very different socioeconomic backgrounds. The inclusion of informant data adds significantly to the performance of the CSI 'D' as a dementia screen. The combination of informant and cognitive scores in a discriminant score produces better sensitivity and specificity for dementia than cognitive scores alone. The informant score has a significant independent effect in predicting dementia.

Prevalence of Alzheimer's disease and dementia in two communities: Nigerian Africans and African Americans.

OBJECTIVE: This article reports on a prevalence study of dementia and Alzheimer's disease among two groups of subjects with the same ethnic background but widely differing environments. METHOD: The study was conducted among residents aged 65 years and older in two communities: Yorubas (N = 2,494) living in Ibadan, Nigeria, and African Americans (N = 2,212 in the community and N = 106 in nursing homes) living in Indianapolis, Indiana. The study design consisted of a screening stage followed by a clinical assessment stage for selected subjects on the basis of their performance on the screening tests. RESULTS: The age-adjusted prevalence rates of dementia (2.29%) and Alzheimer's disease (1.41%) in the Ibadan sample were significantly lower than those in the Indianapolis sample, both in the community-dwelling subjects alone (4.82% and 3.69%, respectively) and in the combined nursing home and community samples (8.24% and 6.24%, respectively). The prevalence rates of dementia and Alzheimer's disease increased consistently with advancing age in both study groups. CONCLUSIONS: To the authors' knowledge, this is the first study, using the same research method at the two sites, to report significant differences in rates of dementia and Alzheimer's disease in two different communities with similar ethnic origins.

Lack of an association between apolipoprotein E epsilon 4 and Alzheimer's disease in elderly Nigerians.

As part of a community-based study of Alzheimer's Disease (AD) in a Nigerian population aged 65 years and over, we have determined apolipoprotein E (APOE) genotypes on 56 subjects (39 controls and 17 subjects with dementia, including 12 with AD). The epsilon 4 allele of APOE was not associated with AD or dementia in this community-based sample. The epsilon 4 allele frequency was 17.6% in demented patients and 16.7% in AD patients compared with 20.5% in the control subjects. These findings are in marked contrast to the strong association between the epsilon 4 allele and AD in our previously reported study with African Americans.

De novo myotonic dystrophy mutation in a Nigerian kindred.

An expansion of an unstable (CTG)n trinucleotide repeat in the 3' UTR of a gene encoding a putative serine/threonine protein kinase (DMPK) on human chromosome 19q13.3 has been shown to be specific for the myotonic dystrophy (DM) disease phenotype. In addition, a single haplotype composed of nine alleles within and flanking DMPK over a physical distance of 30 kb has been shown to be in complete linkage disequilibrium with DM. This has led to two hypotheses: (1) predisposition for (CTG)n instability results from a founder effect that occurred only once or a few times in human evolution; and (2) elements within the disease haplotype may predispose the (CTG)n repeat to instability. A detailed haplotype analysis of the DM region was conducted on a Nigerian (Yoruba) DM family, the only indigenous sub-Saharan DM case reported to date. Each affected member of this family had an expanded (CTG)n repeat in one of his or her DMPK alleles. However, unlike all other DM populations studied thus far, disassociation of the (CTG)n repeat expansion from other alleles of the putative predisposing haplotype was found. We conclude that the expanded (CTG)n repeat in this family is the result of an independent mutational event. Consequently, the origin of DM is unlikely to be a single mutational event, and the hypothesis that a single ancestral haplotype predisposes to repeat expansion is not compelling.

Xenobiotic metabolism in idiopathic Parkinson's disease in Nigerian Africans.

The acetylator phenotype using sulphadimidine as a probe drug was studied in 20 idiopathic Parkinson's disease (IPD) patients and 21 control subjects. 10(50%) of the IPD patients belonged to the slow acetylator phenotype but this did not differ significantly from the proportion 7 (33%) of control subjects who were slow acetylators. The result does not suggest a role for acetylation in the aetiopathogenesis of IPD in Nigerian African.

Alzheimer's disease in Nigeria.

The age-related dementias of the elderly (those aged 65 years or more) are of major public health importance in developed countries. Developing countries, most of which are undergoing epidemiological transition and greying of population, currently contain more than half of the world's population of elderly, a proportion that would reach 75% by 2020. Apart from reports from China, there is little or no information on the dementias of the elderly in developing countries. Alzheimer's disease, which accounts for two-thirds of dementia of the elderly in Caucasian population, is under-documented and believed to be rare in black Africans. But black Americans who are of black African lineage commonly suffer from Alzheimer's disease. A recent autopsy survey of the brains of elderly Nigerians showed absence of senile plaques and neurofibrillary tangles, the pathognomonic histologic lesions of Alzheimer's disease and ageing found in 25% to 80% of normal undemented elderly Caucasians and Japanese. In a community-based door-to-door survey of a population of 9000, including 932 elderly Nigerians, no subject with dementia as defined by DSM-IIIR was found, although there was significant decline of cognition with age, female sex and less than 6 years of formal education. The distribution of cognitive scores is a highly skewed unimodal curve. We emphasize the potential value of cross-cultural epidemiological studies of ethnic groups in different environments and with different prevalence ratios of Alzheimer's disease, in identifying putative environmental factors for this disease.

Rarity of dementia (by DSM-III-R) in an urban community in Nigeria.

Dementia of the elderly, a public health problem world-wide, is underdocumented in black Africa. We carried out a door-to-door survey in Idikan in NW3 ward, a political and administrative unit, with a population of 9000: in Ibadan city, Nigeria, to determine the burden of dementia. Census and demographic listing was done by trained clinical students who concurrently administered a modified Mini Mental State Examination as a screening instrument to those aged 40 years or more. Only 2 out of 932 subjects refused: 293 (31%) were aged 65 years or more. Those who were positive to the screening test and 20% of negatives were investigated by neurologists. Decline in cognitive function significantly correlated with age, female sex and low level of education. Impaired cognition was present in 41 (4.4%) but was due to depressive disorders in 7 (0.6%) patients. In none of the remaining 34 (3.8%) subjects could a diagnosis of dementia as defined by DSM-III-R be justified.

Cross-cultural studies in Alzheimer's disease.

The search for risk factors for Alzheimer's disease would be greatly enhanced by identification of populations with significantly different prevalence rates, particularly if these populations consisted of ethnic groups now living in different environments and cultures. Evidence is presented that two such groups are worthy of further study: subjects of African origin living in Africa and in the West and Native Americans living on and off reserves.

Epidemiology of age-related dementias in the Third World and aetiological clues of Alzheimer's disease.

The prevalence of age-associated dementia which already constitutes enormous public health problems in many developed industrialised countries, is currently low in many developing countries. Community-based studies and autopsy survey in Nigerian Africans showed absence of Alzheimer's disease (AD). The ageing revolution with enormous increase in the population of the elderly is already occurring in developing countries which are also undergoing epidemiological transition. Geographical epidemiological studies of the age associated dementias, in developing and developed countries, and especially in ethnic groups who live in different environments have great potential in identifying putative risk factors, probably currently present in developed industrialised countries and absent in developing less industrialised countries where the disease is as of now relatively uncommon.