The risk of obstructive sleep apnea and its association with indices of general and abdominal obesity in a Nigerian family practice clinic: a cross-sectional study

Introduction: Obstructive sleep apnea (OSA) is associated with considerable morbidity and mortality. This study assessed the prevalence of high risk of OSA and investigated which anthropometric measure best predicts the OSA risk among patients attending a family practice clinic in a tertiary hospital. Methods: We conducted a descriptive cross-sectional study of 362 consecutive patients (64% females; median age of 54 years). OSA risk was assessed by the Berlin Questionnaire and the patients were divided into two groups according to OSA risk: high and low risk. Anthropometric measurements were conducted as stated in the protocol established in the 3rd National Health and Nutrition Examination Survey. Results: Out of 362 participants, 84 [23.2% (95% CI 19.0%, 28.0%)] had high risk of OSA. Subjects with a high risk of OSA had significantly higher body mass index, waist circumference, hip circumference, and waist-to-height ratio (24.9 vs 23.8, p = 0.002; 89.0 vs 84.0, p < 0.001; 95.0 vs 91.0, p < 0.001; 0.56 vs 0.52, p < 0.001, respectively). Body mass index, waist circumference, hip circumference, and waist-to-height ratio performed similarly in predicting high risk of OSA with Area Under the Curve (AUC) of 0.661, 95% CI (0.592,0.730); 0.659, 95% CI (0.596,0.723); 0.668, 95% CI (0.604,0.733); 0.659 95% CI (0.592,0.725) respectively. The AUCs were similar when the analysis was restricted to those who were overweight. Conclusion: High risk of OSA is moderately prevalent in this population, with measures of central and abdominal adiposity equally predicting the risk

Identifying patients at high risk for obstructive sleep apnoea syndrome in Nigeria: A multicentre observational study

Background: Obstructive sleep apnoea is associated with significant health consequences. A significant proportion of hospitalized patients at risk for obstructive sleep apnoea were never identified and referred for polysomnography for diagnosis. The objective of this study was to determine the factors associated with high risk for obstructive sleep apnoea and use it to identify patients at risk for the condition in tertiary hospitals in Nigeria.Methods: This was a multicentre observational study of adult patients hospitalized in three selected hospitals from 15th January to 17th March 2015. Berlin questionnaire and Epworth sleepiness scale were used to assess for obstructive sleep apnoea risk and excessive daytime sleepiness respectively. Additional questions on traditional risk factors for obstructive sleep apnoea were also obtained.Results: Nine hundred and twenty-six patients were recruited into the study. Respondents’ mean age was 44.3 years ± 15.2years, 486 (52.5%) were females and 556 (60.0%) had one or more medical co-morbidity and none of the patients had a previous diagnosis of obstructive sleep apnoea. Factors that were independently associated with high risk for obstructive sleep apnoea include systemic hypertension(aOR-10.33;95%: CI 6.42-16.61), obesity(aOR-7.87;95% CI: 4.33-14.29); excessive daytime sleepiness (aOR-3.77;95% CI:2.28-6.22), tobacco smoking (aOR-2.99;95% CI: 1.76-5.07), snoring in a first-degree relative (aOR-1.83;95% CI: 1.19-2.81); and the use of sedative (aOR-1.82;95% CI: 1.06-3.15).Conclusions: This study shows that patients with systemic hypertension, obesity, excessive daytime sleepiness, history of smoking, snoring in a firstdegree relative and use of sedatives are at high risk of obstructive sleep apnoea. None of the patients at high risk had a previous diagnosis of sleep apnoea by a physician, highlighting the diagnostic challenges of this condition. The results of this study will assist health care professionals in early identification of individuals at risk of obstructive sleep apnoea and subsequent referral for a sleep study

Targeted next-generation sequencing identifies novel variants in candidate genes for Parkinson’s disease in Black South African and Nigerian patients

Background: The prevalence of Parkinson’s disease (PD) is increasing in sub-Saharan Africa, but little is known about the genetics of PD in these populations. Due to their unique ancestry and diversity, sub-Saharan African populations have the potential to reveal novel insights into the pathobiology of PD. In this study, we aimed to characterise the genetic variation in known and novel PD genes in a group of Black South African and Nigerian patients. Methods: We recruited 33 Black South African and 14 Nigerian PD patients, and screened them for sequence variants in 751 genes using an Ion AmpliSeq™ Neurological Research panel. We used bcftools to filter variants and annovar software for the annotation. Rare variants were prioritised using MetaLR and MetaSVM prediction scores. The effect of a variant on ATP13A2’s protein structure was investigated by molecular modelling. Results: We identified 14,655 rare variants with a minor allele frequency ≤ 0.01, which included 2448 missense variants. Notably, no common pathogenic mutations were identified in these patients. Also, none of the known PD-associated mutations were found highlighting the need for more studies in African populations. Altogether, 54 rare variants in 42 genes were considered deleterious and were prioritized, based on MetaLR and MetaSVM scores, for follow-up studies. Protein modelling showed that the S1004R variant in ATP13A2 possibly alters the conformation of the protein. Conclusions: We identified several rare variants predicted to be deleterious in sub-Saharan Africa PD patients; however, further studies are required to determine the biological effects of these variants and their possible role in PD. Studies such as these are important to elucidate the genetic aetiology of this disorder in patients of African ancestry

Interleukin-6 (\u3cem\u3eIL-6\u3c/em\u3e) rs1800796 and Cyclin Dependent Kinase Inhibitor (\u3cem\u3eCDKN2A/CDKN2B\u3c/em\u3e) rs2383207 Are Associated with Ischemic Stroke in Indigenous West African Men

Background—Inherited genetic variations offer a possible explanation for the observed peculiarities of stroke in sub – Saharan African populations. Interleukin–6 polymorphisms have been previously associated with ischemic stroke in some non-African populations. Aim—Herein we investigated, for the first time, the association of genetic polymorphisms of IL-6 and CDKN2A- CDKN2B and other genes with ischemic stroke among indigenous West African participants in the Stroke Investigative Research and Education Network (SIREN) Study. Methods—Twenty-three previously identified single nucleotide polymorphisms (SNPs) in 14 genes of relevance to the neurobiology of ischemic stroke were investigated. Logistic regression models adjusting for known cardiovascular disease risk factors were constructed to assess the associations of the 24 SNPs in rigorously phenotyped cases (N=429) of ischemic stroke (Men = 198; Women = 231) and stroke– free (N=483) controls (Men = 236; Women = 247). Results—Interleukin-6 (IL6) rs1800796 (C minor allele; frequency: West Africans = 8.6%) was significantly associated with ischemic stroke in men (OR = 2.006, 95% CI = [1.065, 3.777], p = 0.031) with hypertension in the model but not in women. In addition, rs2383207 in CDKN2A/CDKN2B (minor allele A with frequency: West Africans = 1.7%) was also associated with ischemic stroke in men (OR = 2.550, 95% CI = [1.027, 6.331], p = 0.044) with primary covariates in the model, but not in women. Polymorphisms in other genes did not show significant association with ischemic stroke. Conclusion—Polymorphisms rs1800796 in IL6 gene and rs2383207 in CDKN2A/CDKN2B gene have significant associations with ischemic stroke in indigenous West African men. CDKN2A/CDKN2B SNP rs2383207 is independently associated with ischemic stroke in indigenous West African men. Further research should focus on the contributions of inflammatory genes and other genetic polymorphisms, as well as the influence of sex on the neurobiology of stroke in people of African ancestry

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

Dyslipidaemia as a risk factor in the occurrence of stroke in Nigeria: prevalence and patterns

Introduction: stroke is a major public health problem worldwide. Hypertension, diabetes mellitus, dyslipidaemia and smoking are some of the common modifiable risk factors in the occurrence of stroke. Therefore, this study was designed to assess the prevalence and patterns of dyslipidaemia among individuals with acute stroke. Methods: this is a retrospective descriptive cross-sectional study, carried out in the Departments of Medicine at the LAUTECH Teaching hospital, Ogbomoso and General Hospital, Orile-Agege, Lagos, South-West, Nigeria, over a 18-month period between September 2012 and February 2014. One hundred and six (106) patients with acute stroke confirmed with computed tomography (CT) brain scan were recruited. Clinical features, risk factors, lipid profiles and stroke patterns were identified. Results: mean age was significantly higher in ischaemiac stroke compared to haemorrhagic (64.08±10.87 Vs, 56.21±12.38years, p=0.001). There was slight male preponderance in both stroke types (1.3:1). Out of 106 patients, 65 (61.3%) had ischaemic stroke, 38 (35.8%) haemorrhagic and 3 (2.9%) with subarachnoid haemorrhage. Dyslipidaemia is the most frequent risk factor (85.9%), followed by hypertension (66.0%) and diabetes mellitus (15.1%). Dyslipidaemia was significantly higher in the ischaemic stroke compared to haemorrhagic. Reduced HDL-cholesterol is the most prevalent fraction of lipid abnormalities (74.5%). Conclusion: this study showed a significant association (85.9%) between dyslipidaemia and stroke. Our study showed low HDL-C as a potential risk factor for stroke. Hence, prevention of dyslipidaemia as well as other risk factors is the key to reducing the burden of stroke in our country.The Pan African Medical Journal 2016;2

Prevalence, predictors and effects of shift work sleep disorder among nurses in a Nigerian teaching hospital

Abstract Background This study evaluated the prevalence, predictors and effects of Shift Work Sleep Disorder (SWSD) among nurses in a Nigerian teaching hospital. Methods Eighty-eight nurses (44 each from the pool of shift and non-shift nurses), who emerged by simple random sampling, participated in the study. Socio-demographic data and health complaints were obtained with questionnaires. Each participant was assessed with Epworth sleepiness scale (ESS), insomnia severity index (ISI) and sleep log, while SWSD cases were ascertained by applying the International Classification of Sleep Disorders (ICSD-2) criteria. Body mass index, blood pressure, body temperature and salivary cortisol levels were also determined. Results Generally, results showed that the shift group; comprising of shift nurses, recorded higher values of biophysical profiles and more health complaints than the non-shift group (control); comprising of non-shift nurses. Also, 19 (43.2%) of the shift nurses fulfilled the criteria for SWSD, on this basis, the shift group was divided into two: SWSD (n = 19) and No SWSD (n = 25). And within the shift group, the SWSD group had higher systolic (p = 0.014), diastolic (p = 0.012), and mean arterial (p = 0.009) blood pressures; they also recorded higher temperature (p = 0.001), higher salivary cortisol levels (p = 0.027) and more health complaints. Conclusion The results of this study indicate that rotating shift work among nurses is associated with increased level of health complaints and physiologic indices of stress as well as sleep impairment

Targeted next-generation sequencing identifies novel variants in candidate genes for Parkinson’s disease in Black South African and Nigerian patients

CITATION: Oluwole, O. G., et al. 2020. Targeted next-generation sequencing identifies novel variants in candidate genes for Parkinson’s disease in Black South African and Nigerian patients. BMC Medical Genetics, 21:23, doi:10.1186/s12881-020-0953-1.The original publication is available at https://bmcmedgenet.biomedcentral.comBackground: The prevalence of Parkinson’s disease (PD) is increasing in sub-Saharan Africa, but little is known about the genetics of PD in these populations. Due to their unique ancestry and diversity, sub-Saharan African populations have the potential to reveal novel insights into the pathobiology of PD. In this study, we aimed to characterise the genetic variation in known and novel PD genes in a group of Black South African and Nigerian patients. Methods: We recruited 33 Black South African and 14 Nigerian PD patients, and screened them for sequence variants in 751 genes using an Ion AmpliSeq™ Neurological Research panel. We used bcftools to filter variants and annovar software for the annotation. Rare variants were prioritised using MetaLR and MetaSVM prediction scores. The effect of a variant on ATP13A2’s protein structure was investigated by molecular modelling. Results: We identified 14,655 rare variants with a minor allele frequency ≤ 0.01, which included 2448 missense variants. Notably, no common pathogenic mutations were identified in these patients. Also, none of the known PD-associated mutations were found highlighting the need for more studies in African populations. Altogether, 54 rare variants in 42 genes were considered deleterious and were prioritized, based on MetaLR and MetaSVM scores, for follow-up studies. Protein modelling showed that the S1004R variant in ATP13A2 possibly alters the conformation of the protein. Conclusions: We identified several rare variants predicted to be deleterious in sub-Saharan Africa PD patients; however, further studies are required to determine the biological effects of these variants and their possible role in PD. Studies such as these are important to elucidate the genetic aetiology of this disorder in patients of African ancestry.https://bmcmedgenet.biomedcentral.com/articles/10.1186/s12881-020-0953-1Publisher's versio

Serum reference intervals of micronutrients, vitamins, and interleukins among healthy adults in South-Western Nigeria

Objectives: Clinical decision making depends mostly on appropriate application of numerical pathology reports from laboratory results, interpreted by comparison with reference intervals. We determined serum reference intervals of micronutrients, vitamins, and detectable interleukins among healthy adults in South-Western Nigeria. Design and methods: This prospective study used a priori selection approach in blood-donors. They were screened for conditions that could elicit cytokine production.Serum micronutrients were assayed using Atomic Absorption Spectrophotometry; interleukins and vitamins by high Performance Liquid Chromatography. The reference intervals (RIs) were estimated at 2.5th percentile and 97.5th percentile. Results: One hundred and eighteen (118) apparently healthy subjects, aged 18–56 years; 113 (95.8%) being 18–44years, and 5 (4.2%): 45–56 years; mostly males, 13 (11.02%) females, all Africans of Yoruba ethnicity.Estimated reference limits were: Zinc: 9.49–20.54 μmol/L, Selenium: 0.50–1.11 μmol/L, Copper: 13.86–27.97 μmol/L, Iron: 14.19–32.07 μmol/L, Manganese: 6.24–16.37 nmol/L; Magnesium: 0.78–1.62 mmol/L.Vitamins: A-1.08–2.39 μmol/L; D: 59.89–164.42 μmol/L; E: 7.13–19.45 μmol/L; K: 0.16–0.42 nmol/L; B1: 74.09–201.56 nmol/L; B6: 0.12–0.29 nmol/L; B12: 155.55–407.96 pmol/L; C: 47.74–112.99 μmol/L.Detected interleukins (IL-1 to IL-18): IL-1: 0.58–1.24 ng/L, IL-2: 0.09–0.18 ng/L, IL-3: 0.39–0.89 ng/L, IL-4: 0.27–0.58 ng/L, ….to IL-18: 0.74–1.56 ng/L. Conclusions: The RI derived from this study for serum micronutrient, vitamin and interleukin concentrations are the first published for our population. They are in general agreement with those published from other geographical climes but there are differences at the lower and upper limits of the RI. The study reinforces the importance of deriving RI for the population that a clinical laboratory will serve

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