Identification of genetic risk loci and causal insights associated with Parkinson's disease in African and African admixed populations: a genome-wide association study.

BACKGROUND: An understanding of the genetic mechanisms underlying diseases in ancestrally diverse populations is an important step towards development of targeted treatments. Research in African and African admixed populations can enable mapping of complex traits, because of their genetic diversity, extensive population substructure, and distinct linkage disequilibrium patterns. We aimed to do a comprehensive genome-wide assessment in African and African admixed individuals to better understand the genetic architecture of Parkinson's disease in these underserved populations. METHODS: We performed a genome-wide association study (GWAS) in people of African and African admixed ancestry with and without Parkinson's disease. Individuals were included from several cohorts that were available as a part of the Global Parkinson's Genetics Program, the International Parkinson's Disease Genomics Consortium Africa, and 23andMe. A diagnosis of Parkinson's disease was confirmed clinically by a movement disorder specialist for every individual in each cohort, except for 23andMe, in which it was self-reported based on clinical diagnosis. We characterised ancestry-specific risk, differential haplotype structure and admixture, coding and structural genetic variation, and enzymatic activity. FINDINGS: We included 197 918 individuals (1488 cases and 196 430 controls) in our genome-wide analysis. We identified a novel common risk factor for Parkinson's disease (overall meta-analysis odds ratio for risk of Parkinson's disease 1·58 [95% CI 1·37-1·80], p=2·397 × 10-14) and age at onset at the GBA1 locus, rs3115534-G (age at onset ß=-2·00 [SE=0·57], p=0·0005, for African ancestry; and ß=-4·15 [0·58], p=0·015, for African admixed ancestry), which was rare in non-African or non-African admixed populations. Downstream short-read and long-read whole-genome sequencing analyses did not reveal any coding or structural variant underlying the GWAS signal. The identified signal seems to be associated with decreased glucocerebrosidase activity. INTERPRETATION: Our study identified a novel genetic risk factor in GBA1 in people of African ancestry, which has not been seen in European populations, and it could be a major mechanistic basis of Parkinson's disease in African populations. This population-specific variant exerts substantial risk on Parkinson's disease as compared with common variation identified through GWAS and it was found to be present in 39% of the cases assessed in this study. This finding highlights the importance of understanding ancestry-specific genetic risk in complex diseases, a particularly crucial point as the Parkinson's disease field moves towards targeted treatments in clinical trials. The distinctive genetics of African populations highlights the need for equitable inclusion of ancestrally diverse groups in future trials, which will be a valuable step towards gaining insights into novel genetic determinants underlying the causes of Parkinson's disease. This finding opens new avenues towards RNA-based and other therapeutic strategies aimed at reducing lifetime risk of Parkinson's disease. FUNDING: The Global Parkinson's Genetics Program, which is funded by the Aligning Science Across Parkinson's initiative, and The Michael J Fox Foundation for Parkinson's Research.

Genome-wide Association Identifies Novel Etiological Insights Associated with Parkinson's Disease in African and African Admixed Populations.

Background: Understanding the genetic mechanisms underlying diseases in ancestrally diverse populations is a critical step towards the realization of the global application of precision medicine. The African and African admixed populations enable mapping of complex traits given their greater levels of genetic diversity, extensive population substructure, and distinct linkage disequilibrium patterns. Methods: Here we perform a comprehensive genome-wide assessment of Parkinson's disease (PD) in 197,918 individuals (1,488 cases; 196,430 controls) of African and African admixed ancestry, characterizing population-specific risk, differential haplotype structure and admixture, coding and structural genetic variation and polygenic risk profiling. Findings: We identified a novel common risk factor for PD and age at onset at the GBA1 locus (risk, rs3115534-G; OR=1.58, 95% CI = 1.37 - 1.80, P=2.397E-14; age at onset, BETA =-2.004, SE =0.57, P = 0.0005), that was found to be rare in non-African/African admixed populations. Downstream short- and long-read whole genome sequencing analyses did not reveal any coding or structural variant underlying the GWAS signal. However, we identified that this signal mediates PD risk via expression quantitative trait locus (eQTL) mechanisms. While previously identified GBA1 associated disease risk variants are coding mutations, here we suggest a novel functional mechanism consistent with a trend in decreasing glucocerebrosidase activity levels. Given the high population frequency of the underlying signal and the phenotypic characteristics of the homozygous carriers, we hypothesize that this variant may not cause Gaucher disease. Additionally, the prevalence of Gaucher's disease in Africa is low. Interpretation: The present study identifies a novel African-ancestry genetic risk factor in GBA1 as a major mechanistic basis of PD in the African and African admixed populations. This striking result contrasts to previous work in Northern European populations, both in terms of mechanism and attributable risk. This finding highlights the importance of understanding population-specific genetic risk in complex diseases, a particularly crucial point as the field moves toward precision medicine in PD clinical trials and while recognizing the need for equitable inclusion of ancestrally diverse groups in such trials. Given the distinctive genetics of these underrepresented populations, their inclusion represents a valuable step towards insights into novel genetic determinants underlying PD etiology. This opens new avenues towards RNA-based and other therapeutic strategies aimed at reducing lifetime risk. Evidence Before this Study: Our current understanding of Parkinson's disease (PD) is disproportionately based on studying populations of European ancestry, leading to a significant gap in our knowledge about the genetics, clinical characteristics, and pathophysiology in underrepresented populations. This is particularly notable in individuals of African and African admixed ancestries. Over the last two decades, we have witnessed a revolution in the research area of complex genetic diseases. In the PD field, large-scale genome-wide association studies in the European, Asian, and Latin American populations have identified multiple risk loci associated with disease. These include 78 loci and 90 independent signals associated with PD risk in the European population, nine replicated loci and two novel population-specific signals in the Asian population, and a total of 11 novel loci recently nominated through multi-ancestry GWAS efforts.Nevertheless, the African and African admixed populations remain completely unexplored in the context of PD genetics. Added Value of this Study: To address the lack of diversity in our research field, this study aimed to conduct the first genome-wide assessment of PD genetics in the African and African admixed populations. Here, we identified a genetic risk factor linked to PD etiology, dissected African-specific differences in risk and age at onset, characterized known genetic risk factors, and highlighted the utility of the African and African admixed risk haplotype substructure for future fine-mapping efforts. We identified a novel disease mechanism via expression changes consistent with decreased GBA1 activity levels. Future large scale single cell expression studies should investigate the neuronal populations in which expression differences are most prominent. This novel mechanism may hold promise for future efficient RNA-based therapeutic strategies such as antisense oligonucleotides or short interfering RNAs aimed at preventing and decreasing disease risk. We envisage that these data generated under the umbrella of the Global Parkinson's Genetics Program (GP2) will shed light on the molecular mechanisms involved in the disease process and might pave the way for future clinical trials and therapeutic interventions. This work represents a valuable resource in an underserved population, supporting pioneering research within GP2 and beyond. Deciphering causal and genetic risk factors in all these ancestries will help determine whether interventions, potential targets for disease modifying treatment, and prevention strategies that are being studied in the European populations are relevant to the African and African admixed populations. Implications of all the Available Evidence: We nominate a novel signal impacting GBA1 as the major genetic risk factor for PD in the African and African admixed populations. The present study could inform future GBA1 clinical trials, improving patient stratification. In this regard, genetic testing can help to design trials likely to provide meaningful and actionable answers. It is our hope that these findings may ultimately have clinical utility for this underrepresented population.

MAPT allele and haplotype frequencies in Nigerian Africans: Population distribution and association with Parkinson's disease risk and age at onset.

INTRODUCTION: The association between MAPT and PD risk may be subject to ethnic variability even within populations of similar geographical origin. Data on MAPT haplotype frequencies, and its association with PD risk in black Africans are lacking. We aimed to determine the frequencies of MAPT haplotypes and their role as risk factors for PD and age at onset in Nigerians. METHODS: The haplotype and genotype frequencies of MAPT rs1052553 were analysed in 907 individuals with PD and 1022 age-matched healthy controls from the Nigeria Parkinson's Disease Research network cohort. Clinical data related to PD included age at study, age at onset (AAO), and disease duration. RESULTS: The frequency of the H1 haplotype was 98.7% in PD, and 99.1% in controls (p = 0.19). The H2 haplotype was present in - 1.3% of PD and 0.9% of controls (p = 0.24). The most frequent MAPT genotype was H1H1 (PD - 97.5%, controls - 98.2%). The H1 haplotype was not associated with PD risk after accounting for gender and AAO (Odds ratio for H1/H1 vs H1/H2 and H2/H2: 0.68 (95% CI:0.39-1.28); p = 0.23). CONCLUSIONS: Our findings support previous studies that report a low frequency of the MAPT H2 haplotype in black ancestry Africans but document its occurrence in Nigerians. The MAPT H1 haplotype was not associated with an increased risk or age at onset of PD in this cohort.

MAPT allele and haplotype frequencies in Nigerian Africans: population distribution and association with Parkinson's disease risk and age at onset.

Background: The microtubule-associated protein tau ( MAPT ) gene is critical because of its putative role in the causal pathway of neurodegenerative diseases including Parkinson's disease (PD). However, there is a lack of clarity regarding the link between the main H1 haplotype and risk of PD. Inconsistencies in reported association may be driven by genetic variability in the populations studied to date. Data on MAPT haplotype frequencies in the general population and association studies exploring the role of MAPT haplotypes in conferring PD risk in black Africans are lacking. Objectives: To determine the frequencies of MAPT haplotypes and explore the role of the H1 haplotype as a risk factor for PD risk and age at onset in Nigerian Africans. Methods: The haplotype and genotype frequencies of MAPT rs1052553 were analysed using PCR-based KASP™ in 907 individuals with PD and 1,022 age-matched neurologically normal controls from the Nigeria Parkinson's Disease Research (NPDR) network cohort. Clinical data related to PD included age at study, age at onset, and disease duration. Results: The frequency of the main MAPT H1 haplotype in this cohort was 98.7% in individuals with PD, and 99.1% in healthy controls (p=0.19). The H2 haplotype was present in 41/1929 (2.1%) of the cohort (PD - 1.3%; Controls - 0.9%; p=0.24). The most frequent MAPT genotype was H1H1 (PD - 97.5%, controls - 98.2%). The H1 haplotype was not associated with PD risk after accounting for gender and age at onset (Odds ratio for H1/H1 vs H1/H2 and H2/H2: 0.68 (95% CI:0.39-1.28); p=0.23). Conclusions: Our findings support previous studies that report a low frequency of the MAPT H2 haplotype in black ancestry Africans, but document its occurrence in the Nigerian population (2.1%). In this cohort of black Africans with PD, the MAPT H1 haplotype was not associated with an increased risk or age at onset of PD.

Telemedicine ready or not? A cross-sectional assessment of telemedicine maturity of federally funded tertiary health institutions in Nigeria.

Introduction and objective: Telemedicine has reinforced its position as a means for the continuity of healthcare services and a cost-effective approach to improving health equity as demonstrated during the COVID-19 pandemic. The preparedness of health systems for telemedicine is an indicator of the scalability of their services, especially during catastrophes. We aimed to assess the maturity and preparedness of federally funded tertiary health institutions in Nigeria, to deploy telemedicine as such data are currently lacking and are required to drive improvements in health services delivery. Methods: We conducted a cross-sectional survey of thirty randomly selected federally funded tertiary health institutions in Nigeria using the Pan American Health Organization's tool for assessing the maturity level of health institutions to implement telemedicine between 17 September 2020 and 1 September 2021. Descriptive statistics were used for overall maturity levels and non-parametric tests to compare scores for overall maturity and specific Pan American Health Organization domains per region. The level of significance was set at p-value <0.05. Results: The response rate was 77.4% (24 of 30 randomly polled federally funded tertiary health institutions responded). Overall, the median telemedicine maturity level was 2.0 (1.75) indicating a beginner level. No significant inter-zonal difference in the median overall maturity level (p = 0.87). The median maturity levels for telemedicine readiness in specific domains were organizational readiness - 2.0 (2.0), processes 1.0 (1.0), digital environment 2.0 (3.0), human resources 2.0 (1.0), regulatory issues - 1.5 (1.0) and expertise 2.0 (2.0); mostly at beginner level, with no inter-zonal differences. Most participating institutions had no initiatives in place for domains of processes and regulatory issues. Conclusions: The current telemedicine maturity level of federally funded tertiary health institutions in Nigeria is at the beginner level. This behoves policy-makers to advance the implementation and deployment of telemedicine nationwide as part of digital quality healthcare, to improve health equity and to ensure continuity of healthcare services in the event of another pandemic.

APOE E4 is associated with impaired self-declared cognition but not disease risk or age of onset in Nigerians with Parkinson's disease.

The relationship between APOE polymorphisms and Parkinson's disease (PD) in black Africans has not been previously investigated. We evaluated the association between APOE polymorphic variability and self-declared cognition in 1100 Nigerians with PD and 1097 age-matched healthy controls. Cognition in PD was assessed using the single item cognition question (item 1.1) of the MDS-UPDRS. APOE genotype and allele frequencies did not differ between PD and controls (p > 0.05). No allelic or genotypic association was observed between APOE and age at onset of PD. In PD, APOE ε4/ε4 conferred a two-fold risk of cognitive impairment compared to one or no ε4 (HR: 2.09 (95% CI: 1.13-3.89; p = 0.02)), while APOE ε2 was associated with modest protection against cognitive impairment (HR: 0.41 (95% CI 0.19-0.99, p = 0.02)). Of 773 PD with motor phenotype and APOE characterized, tremor-dominant (TD) phenotype predominated significantly in ε2 carriers (87/135, 64.4%) compared to 22.2% in persons with postural instability/gait difficulty (PIGD) (30/135) and 13.3% in indeterminate (ID) (18/135, 13.3%) (p = 0.037). Although the frequency of the TD phenotype was highest in homozygous ε2 carriers (85.7%), the distribution of motor phenotypes across the six genotypes did not differ significantly (p = 0.18). Altogether, our findings support previous studies in other ethnicities, implying a role for APOE ε4 and ε2 as risk and protective factors, respectively, for cognitive impairment in PD.

The impact of sex on blood pressure and anthropometry trajectories from early adulthood in a Nigerian population: insights into women's cardiovascular disease risk across the lifespan.

BACKGROUND: Sex disparities in blood pressure and anthropometry may account for differences in cardiovascular (CV) risk burden with advancing age; modulated by ethnic variability. We explored trajectories of blood pressures (BPs) and anthropometric indices with age on the basis of sex in an urban Nigerian population. METHODS: We conducted a secondary analysis on data from 5135 participants (aged 16-92 years; 2671(52%) females) from our population-based cross-sectional study of BP profiles. We utilized the WHO STEPS and standardized methods for documenting BPs, body mass index (BMI) and waist circumference (WC). Data was analyzed using Analysis of variance (ANOVA), Spearman correlation analysis and mean difference in variables (with 95% confidence interval). We explored the influence of age and sex on BP profiles and specific anthropometric indices using generalized regression analysis. RESULTS: In those aged 15-44 years, males had significantly higher systolic BP (SBP) and pulse pressure (PP). However, mean SBP and PP rose more steeply in females from 25 to 34 years, intersected with that of males from 45 to 54 years and remained consistently higher. Difference in mean BPs (95% Confidence Interval) (comparing < and > 45 years) was higher in females compared to males for SBP (17.4 (15.8 to 19.0) v. 9.2 (7.7 to 10.7), DBP (9.0 (7.9 to 10.1) v. 7.8 (6.7 to 8.9)), and PP (8.4 (7.3 to 9.5) v. 1.4 (0.3 to 2.5)). Females had significantly higher BMI and WC across all age groups (p < 0.001). Age more significantly correlated with BPs, BMI and WC in females. Interaction models revealed that SBP was significantly predicted by age category in females from (15-54 years), while DBP was only significantly predicted by age in the 15-34-year category (p < 0.01). BMI and WC were significantly predicted by age only in the 25-34-year category in females, (p < 0.01). CONCLUSIONS: Our population demonstrates sex disparity in trajectories of SBP, PP, BMI and WC with age; with steeper rise in females. There is a need to focus on CV risk reduction in females, starting before, or during early adulthood.

Assessment of the utility of a screening tool for COVID-19 diagnosis in an accident and emergency department in Lagos, Nigeria: A pilot study.

The use of reverse transcription-polymerase chain reaction (RT-PCR) is the gold standard laboratory test for diagnosing SARS-CoV-2 infection. However, it has the disadvantage of a long turnaround time and cost. The Nigeria Centre for Disease Control (NCDC) formulated a case definition for COVID-19. We sought to determine the utility of a 14-item, point-weighted clinical screening questionnaire adapted from the NCDC case definition in identifying patients more likely to have the disease. This was to aid prompt clinical decision-making. Methods: We retrospectively reviewed the data of 113 non-surgical patients presenting to the Accident and Emergency Department (A and E) of Lagos University Teaching Hospital, Lagos, Nigeria. Patients were stratified based on screening scores into low (0-2), moderate (3-5) and high (6) pre-test categories. Patients with low and high scores ≥6 were admitted to the A and E and the COVID-19 holding ward, respectively, while the moderate group had chest computed tomography scans to aid further decision-making, pending the outcome of their RT-PCR results. The validity of the triage score as compared to the RT-PCR test result was calculated and the kappa score of agreement was utilised to evaluate the concordance between two triage scores. The optimum cut-off score was also obtained based on the maximal Younden's index. Results: The frequencies of low, moderate and high pre-test scores were 34 (30%), 43 (38.1%) and 36 (31.9%), respectively. Overall, 38.1% (43/113) were RT-PCR positive. RT-PCR was positive in 26.5% (9/34) with low screening scores, 55.8% (24/43) with moderate scores and 27.8% (10/36) with high scores. The sensitivity and specificity of a high score of 6 were 25% and 92.86%, while the lower score of 3 had sensitivity and specificity of 62.5% and 58.6%, respectively. Conclusion: The screening tool showed a high specificity in its initial design, which suggests that anyone with a low score using this tool has a high probability of testing negative. We recommend a cut-off score of 4 (score A) or 6 (score B) of the current screening tool be used to increase the chances of identifying persons with COVID-19 for RT-PCR testing.

A Cross-Sectional Comprehensive Assessment of the Profile and Burden of Non-motor Symptoms in Relation to Motor Phenotype in the Nigeria Parkinson Disease Registry Cohort.

BACKGROUND: Data on non-motor symptoms (NMS) in black Africans with Parkinson's disease (PD) are sparse. OBJECTIVE: To describe the profile of NMS in the Nigeria PD Registry (NPDR) cohort and explore the relationship between NMS and PD motor phenotype. METHODS: We conducted a cross-sectional study of the frequency and burden of NMS, based on the non-motor symptoms scale (NMSS) and the Chaudhuri method respectively in our cohort. Baseline demographics, disease characteristics (Hoehn and Yahr stage, MDS-UPDRS total score and Part III motor score), motor phenotype (based on Stebbin et al's algorithm), and levodopa equivalent daily dose (LEDD) were documented. RESULTS: Data are presented for 825 PD whose mean age at study was 63.7 ± 10.1 years, female sex-221 [26.8%] while median PD duration was 36 months. PD phenotypes included tremor-dominant 466 (56.5%), postural instability and gait disorder (PIGD) 259 (31.4%), and indeterminate 100 (12.1%). 82.6% were on treatment (median LEDD of 500 mg/24 hours). 804 (97.5%) endorsed at least 1 NMS. The median NMSS score was 26.0 while subscores for urinary and sexual function domains were significantly higher in males (P < 0.05). PIGD-PD had more frequent NMS and higher frequency of severe/very severe NMSS burden (P = 0.000 for both). Nocturia and fatigue were the most prevalent NMS overall and across motor subtypes. PIGD phenotype and total UPDRS scores were the independent determinants of NMSS scores (P = 0.000). CONCLUSION: The profile and burden of NMS, and association with motor subtype in our black African cohort is largely similar to descriptions from other populations.

Prevalence of obesity and an interrogation of the correlation between anthropometric indices and blood pressures in urban Lagos, Nigeria.

Adverse cardiovascular outcomes are linked to higher burden of obesity and hypertension. We conducted a secondary analysis of data for 5135 participants aged ≥ 16 years from our community-based hypertension prevalence study to determine the prevalence of obesity and association between multiple anthropometric indices and blood pressure (BP). The indices were waist circumference (WC), body mass index (BMI), waist-to-height ratio (WHtR), waist-to-hip ratio (WHR), a body shape index(ABSI), abdominal volume index (AVI), body adiposity index (BAI), body roundness index (BRI), visceral adiposity index (VAI) and conicity index (CI). We performed statistical analyses to determine the association, predictive ability, cutoff values and independent determinants of hypertension. Crude prevalence of obesity was 136 per 1000 (95% confidence interval 126-146). BMI had the strongest correlation with systolic and diastolic BP (rs = 0.260 and 0.264, respectively). Indices of central adiposity (AVI, WC, WHtR, BRI) were the strongest predictors of hypertension (≥ 140/90 mmHg), and their cut-off values were generally higher in females than males. WHR, age, BMI and CI were independent determinants of hypertension ≥ 140 mmHg (p < 0.05). We conclude that, based on this novel study, measures of central adiposity are the strongest predictors and independent determinants of hypertension in our population, and cut-off values vary from previously recommended standards.

Negative screening for 12 rare LRRK2 pathogenic variants in a cohort of Nigerians with Parkinson's disease.

Leucine-rich repeat kinase 2 (LRRK2) gene mutations are the most common genetic cause of Parkinson's disease (PD). More than 300 rare LRRK2 variants have been described, with approximately 17 having confirmed or probable pathogenic role in PD. The distribution differs across ethnic groups, but no PD-related LRRK2 pathogenic variant has been described in persons of Black African ancestry within or outside Africa. We previously reported the absence of LRRK2 p.Gly2019Ser mutation in 126 PD and 55 controls from Nigeria. Using Kompetitive Allele Specific Polymerase Chain Reaction, we screened a new cohort of 92 Nigerians with PD and 210 ethnically matched controls for 12 rare LRRK2 variants shown to be pathogenic in other ethnic populations, including p.Gly2019Ser, p.Arg1441His, p.Gly2385Arg, p.Ala419Val, p.Arg1628Pro, p.Pro755Leu, p.Ile2020Thr, and Tyr1699Cys. All were absent in PD and controls, endorsing our previous findings and confirming that rare LRRK2 pathogenic variants reported in Caucasians, Asians, and persons of mixed ancestry are absent in West Africans. Future studies applying next generation sequencing are necessary to explore novel LRRK2 variants indigenous to Black Africans.

Translation, Validation, Diagnostic Accuracy, and Reliability of Screening Questionnaire for Parkinsonism in Three African Countries.

BACKGROUND: Availability of validated Parkinson's disease (PD) questionnaires in languages spoken in Africa will enable the conduct of epidemiological studies. OBJECTIVE: The aims of the current study were to develop cross-cultural translated and validated Arabic and French versions of a PD screening questionnaire, and determine its diagnostic accuracy for recognition of parkinsonism in early and moderate-advanced PD in three countries (Cameroon (French), Egypt (Arabic), and Nigeria (English)). METHODS: This cross-sectional study screened 159 participants (81 PD and 78 controls) using the PD screening questionnaire. The questionnaire was translated into Arabic and French versions using standard protocols. Cognitive function was assessed using the Montreal Cognitive Assessment and the Identification and Intervention for Dementia in Elderly Africans cognitive screen. Co-morbidity burden was documented using the Charlson Comorbidity Index. PD severity and stage were evaluated using the MDS Unified Parkinson Disease Rating Scale and the Hoehn and Yahr scale respectively. RESULTS: Both PD patients and controls were matched regarding age, gender, education, and co-morbidity burden. The PD screening questionnaire scores were significantly higher in PD (median 8.0, IQR 6.0-10.0) in contrast to controls (0.0, IQR 0.0-0.0) (p < 0.0001), with a similar pattern and level of significance across all country sites. In ROC analysis, the questionnaire demonstrated high diagnostic accuracy for PD overall, with an AUC of 0.992 (95% CI 0.981-1.002). CONCLUSION: The Arabic, French, and English versions of this PD screening questionnaire are valid and accurate screening instruments for recognition of Parkinsonism. This paves the way for conducting epidemiological studies in many African countries.

The Nigeria Parkinson Disease Registry: Process, Profile, and Prospects of a Collaborative Project.

BACKGROUND: Clinical disease registries are useful for quality improvement in care, benchmarking standards, and facilitating research. Collaborative networks established thence can enhance national and international studies by generating more robust samples and credible data and promote knowledge sharing and capacity building. This report describes the methodology, baseline data, and prospects of the Nigeria Parkinson Disease Registry. METHODS: This national registry was established in November 2016. Ethics approval was obtained for all sites. Basic anonymized data for consecutive cases fulfilling the United Kingdom Parkinson's Disease Brain Bank criteria (except the exclusion criterion of affected family members) are registered by participating neurologists via a secure registry website (www.parkinsonnigeria.com) using a minimal common data capture format. RESULTS: The registry had captured 578 participants from 5 of 6 geopolitical zones in Nigeria by July 2019 (72.5% men). Mean age at onset was 60.3 ± 10.7 years; median disease duration (interquartile range) was 36 months (18-60.5 months). Young-onset disease (<50 years) represented 15.2%. A family history was documented in 4.5% and 7.8% with age at onset <50 and ≥ 50, respectively. The most frequent initial symptom was tremor (45.3%). At inclusion, 93.4% were on treatment (54.5% on levodopa monotherapy). Per-capita direct cost for the registry was $3.37. CONCLUSIONS: This is the first published national Parkinson's disease registry in sub-Saharan Africa. The registry will serve as a platform for development of multipronged evidence-based policies and initiatives to improve quality of care of Parkinson's disease and research engagement in Nigeria. © 2020 International Parkinson and Movement Disorder Society.

Prevalence of hypertension and blood pressure profile amongst urban-dwelling adults in Nigeria: a comparative analysis based on recent guideline recommendations.

BACKGROUND: Hypertension is the major risk factor for cardiovascular diseases and prevalence rates are critical to understanding the burden and envisaging health service requirements and resource allocation. We aimed to provide an update of the current prevalence of hypertension and blood pressure profiles of adults in urban Nigeria. METHODS: Cross sectional population-based survey in Lagos, Nigeria. Participants were selected using stratified multistage sampling. Relevant sections of the World Health Organization STEPwise approach to chronic disease risk factor surveillance were utilized for data collection. Blood pressures were categorized based on both the current American College of Cardiology/American Heart Association (ACC/AHA) 2017 guidelines and the pre-existing Joint National Committee on Hypertension 7 (JNC7) (2003) categories. RESULTS: There were 5365 participants (51.8% female), age range of 16-92 years, and mean age ± SD 37.6 ± 13.1. The mean ± SD systolic and diastolic blood pressures were 126.8 ± 18.6 and 80.6 ± 13.2 respectively. There was significant correlation between both systolic and diastolic blood pressures and age (Pearson correlation 0.372 and 0.357 respectively and p = 0.000 in both instances). The prevalence of hypertension was 55.0% (3003) and 27.5% (1473) based on the ACC/AHA 2017 guideline and the JNC7 2003 guidelines respectively. Body mass index was positively correlated with systolic and diastolic BP (p = 0.000). CONCLUSIONS: Over half of the adult population in this major Nigerian city are classified to have hypertension by the recent guideline. There is an urgent need to develop and implement strategies for primordial prevention of hypertension (and obesity) and to restructure our healthcare delivery systems to adequately cater for the current and emerging hypertensive population.

A Nationwide Survey of Parkinson's Disease Medicines Availability and Affordability in Nigeria.

BACKGROUND AND OBJECTIVES: Limited access to medicines can impact negatively on outcomes in people with Parkinson's disease (PD). The study objectives were to determine the availability and assess the affordability of antiparkinsonian medications in pharmacies across Nigeria. METHODS: This was a cross-sectional nationwide study utilizing the World Health Organization/Health Action Initiative methodology. Strategically selected private- and public-sector pharmacies in the six geopolitical zones of Nigeria were surveyed for availability of medicines for management of early and advanced PD. The nine categories were: levodopa/peripheral decarboxylase inhibitors, dopamine receptor agonists, monoamine oxidase type B inhibitors, anticholinergics, catechol-o-methyl transferase inhibitors, atypical antipsychotics, antidepressants, antidementia drugs, and miscellaneous (e.g., drugs for orthostatism, urinary incontinence, and sleep disturbance). Unaffordability was defined as paying more than 1 days' wages (>N600 or > US$1.67) for a standard 30-day supply. RESULTS: One hundred twenty-three pharmacies were surveyed (62 private [50.4%] and 61 public sector [49.6%]; range of 15-25 pharmacies in each geopolitical zone). Private exceeded public-sector availability across all nine categories of PD medicines (P < 0.05). The most available medicines were dopamine receptor agonists (68.3%; predominantly ergot-derived bromocriptine), anticholinergics (56.1%; mainly trihexyphenidyl), and l-dopa formulations (48%; mainly 250/25 l-dopa/carbidopa). Only two medications (trihexyphenidyl tablets and biperiden injection) were affordable. The average number of day's minimum wages for a 30-day supply of PD medicines was 41.3 days (range, 1-371). CONCLUSIONS: PD medicines access is limited in Nigeria. Strategies, including engagement of stakeholders to consider interventions to improve and prioritize PD medicines access, are urgently warranted.