Short Physical Performance Battery and Study of Osteoporotic Fractures Index in the Exploration of Frailty Among Older People in Cameroon

Objectives: To investigate the relationship between the Short Physical Performance Battery (SPPB) and the Study of Osteoporotic Fractures (SOF) index.Methods: We present data from a cross-sectional survey conducted in Cameroon. Frailty was defined as an SOF index > 0. The sensitivity and specificity of the SPPB were investigated. Principal component analysis (PCA) was performed to assess the contribution of each subtest of the SPPB to the relationship with the SOF.Results: Among 403 people included (49.6% women), average age of 67.1 (±6.2) years, 35.7% were frail according to the SOF. After determining the best SPPB threshold for diagnosing frailty (threshold = 9, Se = 88.9%, Sp = 74.9%), 47.9% were frail according to the SPPB. The first dimension of PCA explained 55.8% of the variability in the data. Among the subtests of the SPPB, the chair stand test item was the component most associated with the SOF index.Conclusion: Despite the overlap between the SOF and the SPPB, our results suggest that a negative result on the five chair-stands test alone would be sufficient to suspect physical frailty

Evolution et synthèse des connaissances sur une pathologie neurologique énigmatique : le Nodding Syndrome

The Nodding Syndrome (NS) is an atypical form of childhood epilepsy that has been prevalent in East Africa for many years. The aim of this thesis was to provide as comprehensive an overview as possible of this condition. To achieve this objective, we first confirmed, through a field survey, the existence of NS cases in the Central African Republic, thus confirming an extension to Central Africa. Next, we conducted a systematic review of the literature which allowed us to: 1) study the contemporary geographical distribution of NS cases (which remains limited to Eastern and Central Africa); 2) identify the limitations and challenges of an inoperative definition of the condition and thus propose one that is suitable for epidemiological investigations; 3) describe the particular clinical presentations of NS; 4) identify the treatments used and their alternatives; and 5) carry out a detailed synthesis of etiological research, since its cause remains unknown. Finally, we have proposed a multicentric survey with the main objective of investigating the possible/probable etiologies of NS. This thesis has thus made it possible to measure this public health burden, which remains limited (for the time being) to sub-Saharan Africa, and to highlight the many challenges facing the scientific community in the fight against this pathology (with its unpredictable epidemiological twists and turns). By gathering and studying almost all the publications on NS up to the end of the year 2021, this work aims at providing a comprehensive view of what is known about NS today, and of the questions that remain unanswered. The epidemiological and clinical contributions may provide new directions on the subject, including helping to design area-specific public health strategies for better management of children affected by this dreadful disease.Le Nodding Syndrome (NS) est une forme d'epilepsie atypique de l'enfant sevissant depuis de nombreuses annees en Afrique de l'Est. L'objectif de cette these etait de faire un etat des lieux le plus exhaustif possible de cette pathologie. Pour atteindre cet objectif, nous avons d'abord confirme, par une enquete de terrain, !'existence de cas de NS en Republique Centrafricaine, confirmant ainsi une extension vers l'Afrique Centrale. Ensuite, nous avons realise une revue systematique de la litterature qui nous a permis : 1) d'etudier la distribution geographique contemporaine des cas de NS (qui reste limite a l'Est et au Centre de l'Afrique); 2) d'identifier les limites et les defis lies a une definition inoperante de cette pathologie et ainsi d'en proposer une qui soit adaptee aux enquetes epidemiologiques ; 3) de decrire les presentations cliniques particulieres du NS ; 4) d'identifier les traitements utilises et leurs alternatives et 5) de realiser une synthese detaillee des recherches a visee etiologique, puisque sa cause demeure toujours inconnue. Enfin, nous avons propose un schema d'etude multicentrique dont l'objectif principal porte sur les etiologies possibles/ probables du NS. Cette these a ainsi permis de mesurer ce fardeau de sante publique qui reste limite (pour !'instant) a l'Afrique sub-saharienne, et de souligner les nombreux defis auxquels la communaute scientifique doit faire face dans la lutte contre cette pathologie (aux rebondissements epidemiologiques imprevisibles). En regroupant et etudiant la quasi-totalite des publications afferant au NS jusqu'a la fin de l'annee 2021, ce travail s'est voulu un apport indispensable pour une vision exhaustive de ce que l'on sait aujourd'hui sur le NS, et des questions qui restent en suspens. Les contributions sur les plans epidemiologique et clinique donneront peut-etre de nouvelles orientations sur le sujet notamment une aide a la conception de strategies de sante publique adaptees a chaque zone pour une meilleure prise en charge des enfants touches par cette pathologie redoutable

Evolution and synthesis of knowledge on an enigmatic neurological pathology : Nodding Syndrome

Le Nodding Syndrome (NS) est une forme d’épilepsie atypique de l’enfant sévissant depuis de nombreuses années en Afrique de l’Est. L’objectif de cette thèse était de faire un état des lieux le plus exhaustif possible de cette pathologie. Pour atteindre cet objectif, nous avons d’abord confirmé, par une enquête de terrain, l’existence de cas de NS en République Centrafricaine, confirmant ainsi une extension vers l’Afrique Centrale. Ensuite, nous avons réalisé une revue systématique de la littérature qui nous a permis : 1) d’étudier la distribution géographique contemporaine des cas de NS (qui reste limité à l’Est et au Centre de l’Afrique) ; 2) d’identifier les limites et les défis liés à une définition inopérante de cette pathologie et ainsi d’en proposer une qui soit adaptée aux enquêtes épidémiologiques ; 3) de décrire les présentations cliniques particulières du NS ; 4) d’identifier les traitements utilisés et leurs alternatives et 5) de réaliser une synthèse détaillée des recherches à visée étiologique, puisque sa cause demeure toujours inconnue. Enfin, nous avons proposé un schéma d’étude multicentrique dont l’objectif principal porte sur les étiologies possibles/ probables du NS. Cette thèse a ainsi permis de mesurer ce fardeau de santé publique qui reste limité (pour l’instant) à l’Afrique sub-saharienne, et de souligner les nombreux défis auxquels la communauté scientifique doit faire face dans la lutte contre cette pathologie (aux rebondissements épidémiologiques imprévisibles). En regroupant et étudiant la quasi-totalité des publications afférant au NS jusqu’à la fin de l’année 2021, ce travail s'est voulu un apport indispensable pour une vision exhaustive de ce que l’on sait aujourd’hui sur le NS, et des questions qui restent en suspens. Les contributions sur les plans épidémiologique et clinique donneront peut-être de nouvelles orientations sur le sujet notamment une aide à la conception de stratégies de santé publique adaptées à chaque zone pour une meilleure prise en charge des enfants touchés par cette pathologie redoutable.The Nodding Syndrome (NS) is an atypical form of childhood epilepsy that has been prevalent in East Africa for many years. The aim of this thesis was to provide as comprehensive an overview as possible of this condition. To achieve this objective, we first confirmed, through a field survey, the existence of NS cases in the Central African Republic, thus confirming an extension to Central Africa. Next, we conducted a systematic review of the literature which allowed us to: 1) study the contemporary geographical distribution of NS cases (which remains limited to Eastern and Central Africa); 2) identify the limitations and challenges of an inoperative definition of the condition and thus propose one that is suitable for epidemiological investigations; 3) describe the particular clinical presentations of NS; 4) identify the treatments used and their alternatives; and 5) carry out a detailed synthesis of etiological research, since its cause remains unknown. Finally, we have proposed a multicentric survey with the main objective of investigating the possible/probable etiologies of NS. This thesis has thus made it possible to measure this public health burden, which remains limited (for the time being) to sub-Saharan Africa, and to highlight the many challenges facing the scientific community in the fight against this pathology (with its unpredictable epidemiological twists and turns). By gathering and studying almost all the publications on NS up to the end of the year 2021, this work aims at providing a comprehensive view of what is known about NS today, and of the questions that remain unanswered. The epidemiological and clinical contributions may provide new directions on the subject, including helping to design area-specific public health strategies for better management of children affected by this dreadful disease

Nodding syndrome en République Centrafricaine

International audienceContexte : « Nodding Syndrome (NS) » est un terme qui apparait pour la première fois en 2012 pour décrire une forme atypique d’épilepsie de l’enfant qui se manifeste par des « hochements de la tête (HT) ». La maladie est restée longtemps limitée en Afrique de l’Est ; elle peut évoluer vers des formes graves et entraîner la mort. La cause de la maladie est inconnue à ce jour.Objectifs : Confirmer l'existence de cas de NS en République centrafricaine (RCA).Méthode : Il s’agissait d’une étude transversale descriptive en population générale. La recherche des cas s’est faite à travers le porte-à-porte dans le village Landja. La confirmation des cas était effectuée par un neurologue dans un centre de santé et un EEG était réalisé. Un traitement était proposé à tous les malades.Résultats : Un total de 6 175 personnes ont été interrogées dans 799 ménages. Après examen des cas, nous avons identifié 5 cas de NS chez des filles âgées de 8 à 16 ans. L'âge d'apparition des crises était compris entre 5 et 12 ans. Un seul cas a été classé comme NS confirmé selon la classification de l'Organisation Mondiale de la Santé en 2012. Trois d'entre eux présentaient un retard mental et deux étaient en dessous de la taille attendue pour leur âge. Des anomalies électroencéphalographiques ont été constatées chez quatre patients.Conclusion : Les cas de Nodding syndrome ont été décrits pour la première fois en RCA. Malgré certaines particularités, ces cas sont similaires à ceux décrits ailleurs. Étant donné que seule une petite partie de la zone touchée a été étudiée, la zone d'étude le long de la rivière Oubangui doit être étendue afin d'évaluer la charge réelle de la NS en RCA

Response to “Nodding Syndrome Associated with Onchocerciasis”

LETTR

Nodding syndrome en République Centrafricaine

International audienceContexte : « Nodding Syndrome (NS) » est un terme qui apparait pour la première fois en 2003 pour décrire une forme atypique d’épilepsie de l’enfant qui se manifeste par des « hochements de la tête (HT) ». La maladie est restée longtemps limitée en Afrique de l’Est ; elle peut évoluer vers des formes graves et entraîner la mort. La cause de la maladie est inconnue à ce jour.Objectifs : Confirmer l'existence de cas de NS en République centrafricaine (RCA).Méthode : Il s’agissait d’une étude transversale descriptive en population générale. La recherche des cas s’est faite à travers le porte-à-porte dans le village Landja. La confirmation des cas était effectuée par un neurologue dans un centre de santé et un EEG était réalisé. Un traitement était proposé à tous les malades.Résultats : Un total de 6 175 personnes ont été interrogées dans 799 ménages. Après examen des cas, nous avons identifié 5 cas de NS chez des filles âgées de 8 à 16 ans. L'âge d'apparition des crises était compris entre 5 et 12 ans. Deux cas ont été classés comme "HN plus" selon la classification de Winkler en 2008 et un seul cas a été classé comme NS confirmé selon la classification de l'OMS en 2012. Trois d'entre eux présentaient un retard mental et deux étaient en dessous de la taille attendue pour leur âge. Des anomalies électroencéphalographiques ont été constatées chez quatre patients.Conclusion : Les cas de Nodding syndrome ont été décrits pour la première fois en RCA. Malgré certaines particularités, ces cas sont similaires à ceux décrits ailleurs. Étant donné que seule une petite partie de la zone touchée a été étudiée, la zone d'étude le long de la rivière Oubangui doit être étendue afin d'évaluer la charge réelle de la NS en RCA

Mapping, Associated Factors, and Pathophysiology of Nodding Syndrome in Africa: A Systematic Review

International audienceIntroduction: Nodding syndrome (NS) remains a poorly understood disorder. For a long time, it has been thought to be restricted to East Africa; however, cases in Central Africa have been increasing over time. The objective of this systematic review (SR) was to provide a summary of the state of knowledge on NS to date.Methods: All original articles published on NS up to November 2021 were searched in four major databases and in the gray literature. Commentaries, editorials, book chapters, books, conference paper, qualitative studies that mentioned NS cases were also included. Data retrieved included study location (with GPS coordinates searched), year of study and publication, population characteristics, definition and diagnosis of NS, associated factors, and treatment if applicable. A meta-analysis of associated factors was performed where possible, and results were presented as odds ratios (ORs) and visualized as forest plots. Geographic information systems were used for cartographic representations. The quality of the articles included was assessed.Results: Of the 876 articles initially identified, 67 (corresponding to 59 studies) were included in the SR. NS is only present in Central and East Africa. Interestingly, there were reports of NS in Central Africa prior to 2010, earlier than previously thought. The way NS diagnosis was established varies according to studies, and the 2012 WHO classification was used in only 60% of the studies. Approximately 11% of the articles did not meet the quality requirements set for this review. In our meta-analysis, the main factor associated with NS was onchocerciasis (OR = 8.8 [4.8, 15.9]). However, the pathophysiology of the disease remains poorly understood. The lack of common anti-epileptic drugs is a significant barrier to the management of head nodding and associated epileptic seizures.Discussion/conclusion: The lack of an operational definition of NS is an obstacle to its diagnosis and, thus, to its appropriate treatment. Indeed, diagnostic difficulties might have led to false positives and false negatives which could have altered the picture of NS presented in this article. Treatment should take into account nutritional and psychological factors, as well as associated infections. Some risk factors deserve further investigation; therefore, we suggest a multicentric study with an etiological focus using a more operational definition of NS

Onchocerciasis in tropical neurology: A scoping review

International audienceBackground: Onchocerciasis is a serious problem in tropical areas. The role of the parasite as a factor associatedwith neurological diseases needs to be addressed because it might involve a reduction of the risk via eliminationstrategies. We performed a systematic scoping review to identify available studies on this association and put intoperspective the different methodological approaches for interpreting the evidence.Methodology: A literature search was conducted using MEDLINE (Pubmed) through October 1, 2020. We includedall the studies evaluating the association between onchocerciasis and four neurological diseases (epilepsy,nodding syndrome, Nakalanga syndrome, and encephalitis) in tropical countries. A descriptive and criticalsummary of the results was conducted to provide an overview of the findings.Results: Overall, 161 articles were identified in the literature search. After full-length examination, we included twelve articles for epilepsy and three for nodding syndrome. Two meta-analyses of case-control studies found a modest strength of the association between O. volvulus and epilepsy. Recent meta-analyses and original studies support a significant association. Epidemiological studies suggest an association between onchocerciasis and nodding syndrome, however, the level of evidence from case-control studies was relatively low. No measure ofassociation was reported for Nakalanga syndrome. There was no specific study on the association between O. volvulus and encephalitis.Conclusion: The association between onchocerciasis and epilepsy seems increasingly likely. However, there are still many unanswered questions about the different clinical presentations of this epilepsy. Strong international collaboration is essential to improve our understanding of risk factors and physiopathological mechanisms of these intriguing conditions

Onchocerciasis in tropical neurology: A scoping review

International audienceBackground: Onchocerciasis is a serious problem in tropical areas. The role of the parasite as a factor associatedwith neurological diseases needs to be addressed because it might involve a reduction of the risk via eliminationstrategies. We performed a systematic scoping review to identify available studies on this association and put intoperspective the different methodological approaches for interpreting the evidence.Methodology: A literature search was conducted using MEDLINE (Pubmed) through October 1, 2020. We includedall the studies evaluating the association between onchocerciasis and four neurological diseases (epilepsy,nodding syndrome, Nakalanga syndrome, and encephalitis) in tropical countries. A descriptive and criticalsummary of the results was conducted to provide an overview of the findings.Results: Overall, 161 articles were identified in the literature search. After full-length examination, we included twelve articles for epilepsy and three for nodding syndrome. Two meta-analyses of case-control studies found a modest strength of the association between O. volvulus and epilepsy. Recent meta-analyses and original studies support a significant association. Epidemiological studies suggest an association between onchocerciasis and nodding syndrome, however, the level of evidence from case-control studies was relatively low. No measure ofassociation was reported for Nakalanga syndrome. There was no specific study on the association between O. volvulus and encephalitis.Conclusion: The association between onchocerciasis and epilepsy seems increasingly likely. However, there are still many unanswered questions about the different clinical presentations of this epilepsy. Strong international collaboration is essential to improve our understanding of risk factors and physiopathological mechanisms of these intriguing conditions

Visual Impairment and Physical Frailty in Sub-Saharan Africa

International audienceBackgroundsAging has been clearly associated with visual and physical performance. Alteration of visual function is associated with negative health outcome such as cognitive decline, disability, loss of mobility.ObjectivesTo determine the relationship between visual impairment (VI) and physical frailty (using the SOF index and SPPB).MethodsData from the Douala Study of Aging, an observational, cross-sectional study. Visual impairment was self-reported. Physical frailty was assessed using the SOF index and the SPPB test. Considering the SOF index, participants meeting one or more criteria (unintentional weight loss, inability to do five chair stands, low energy level) were classified as pre-frail/frail. The SPPB is consisting of three sub-tests : test of balance, chair stands test and gait speed test (range between 0 to 12). Participants with SPPB test score > 9 were classified as fit. Descriptive statistics and linear regression analyses were used to determine the relationship between VI and physical frailty.ResultsThe study sample consisted of 406 patients aged 55 years or older, among whom 49.80 % were female. The mean age of participants was 67.0 (+/- 6.4) years. A total of 359 (88.4 %) have self-reported VI. Considering both test (SOF and SPPB), the prevalence of frailty/pre-frailty was 40 %. After adjustments, the VI was significantly associated with physical frailty (OR :2.88 IC95 % 1.23 - 6.79, P<0.001) and OR : 2.69 IC 95 % 1.31 - 5.55, P< 0.001) respectively for SOF index and SPPB test.ConclusionOur study supports an association between VI and physical frailty defined according to the SOF index and the SPPB. This results suggest that VI could be consider as an indicator of physical frailty among elder persons in Subsaharan Africa