Epidemiology of thromboembolic events in children and adolescents with antiphospholipid syndrome: A systematic review with meta-analysis

BACKGROUND AND AIM

This was a systematic review and meta-analysis of the prevalence of thromboembolic events in children and adolescents with antiphospholipid syndrome (APS).

METHODS

We searched PubMed, EMBASE and Web of Science to select relevant articles published between 1 January 2000 and 27 February 2022. We used the random-effects meta-analysis to estimate pooled point prevalence rates of thromboembolic events in studies with a minimum sample size of 30.

RESULTS

We included five studies reporting data of 336 children and adolescents with primary APS and secondary APS (SAPS). Pooled point prevalence rates of initial general thrombosis, arterial thrombosis, venous thrombosis and stroke in individuals with seropositive APS were 98.2% (95% confidence interval [CI] 87.5-100), 27.6% (95% CI 21.4-34.2), 51.1% (95% CI 38.2-63.9) and 13.4% 95% CI (6.3-22.7), respectively. Pooled point prevalence rates of initial arterial and venous thromboses in children and adolescents with SAPS were 45.7% (95% CI 21.1-71.6) and 29.2% (95% CI 14.8-46), respectively.

CONCLUSION

Arterio-venous thromboembolism is highly frequent in children and adolescents with SAPS. More studies using thrombotic and non-thrombotic APS classification criteria are warranted to better assess the frequency and predictors of thromboembolism in age- and ancestry-diverse pediatric populations affected by different types of APS.

Autoimmune inflammatory myopathy biomarkers

The autoimmune inflammatory myopathy disease spectrum, commonly known as myositis, is a group of systemic diseases that mainly affect the muscles, skin and lungs. Biomarker assessment helps in understanding disease mechanisms, allowing for the implementation of precise strategies in the classification, diagnosis, and management of these diseases. This review examines the pathogenic mechanisms and highlights current data on blood and tissue biomarkers of autoimmune inflammatory myopathies.

Epidemiology of Idiopathic Inflammatory Myopathies in Africa: A Contemporary Systematic Review

BACKGROUND

The epidemiology of idiopathic inflammatory myopathies (IIMs) has been extensively studied in America, Europe, and Asia, but remains unclear in Africa.

OBJECTIVE

The aim of this review was to summarize available data on the epidemiology of IIMs in Africa.

METHODS

We searched MEDLINE, EMBASE, and African Journals Online for studies published up to December 30, 2020, and reporting epidemiological data on IIMs in Africa. Data were combined through narrative synthesis. The review protocol was registered with PROSPERO, CRD42020186781.

RESULTS

We included 39 studies reporting 683 cases (71.7% adults) of IIMs. Incidence rates of ~7.5/1,000,000 person-years and 1.2/1,000,000 person-years were estimated for dermatomyositis (DM), whereas polymyositis (PM) had an incidence rate of 8.8/1,000,000 person-years. Prevalence estimates of 11.49/100,000 and 11/100,000 (95% confidence interval, 0-32) were provided for IIMs and the PM subtype, respectively. Mean age at diagnosis ranged from 7.9 to 57.2 years, and 50% to 100% of the patients were females. Main subtypes of adult-onset IIMs were DM (21%-93%) and PM (12%-79%), whereas the commonest juvenile subtype was juvenile DM (5.8%-9%). Skeletal muscle involvement (56%-100%) was the main disease feature, and esophagus was the most commonly affected internal organ (6%-65.2%). Anti-Jo1/histidyl tRNA synthetase (7%-100%) and anti-Mi2 (17%-45%) antibodies were the most frequent myositis specific antibodies. Early mortality was high (7.8%-45%), and main death causes were infections, cancers and organ damage in respiratory and cardiovascular domains.

CONCLUSIONS

Apart from a potential younger age at onset of adult IIMs in Africa, current sparse data mostly suggest a similar epidemiology between Africa and other regions. Further high-quality studies are required to validate these findings.

Epidemiology of Digital Clubbing and Hypertrophic Osteoarthropathy: A Systematic Review and Meta-analysis

ABSTRACT

Digital clubbing and hypertrophic osteoarthropathy (HOA) are long-standing clinical entities, but their prevalence have not been synthesized. We aimed to estimate the prevalence of digital clubbing and HOA in people with existing medical conditions.We comprehensively searched PubMed, Embase, and Web of Science to select studies addressing HOA or digital clubbing and published through March 23, 2021. Summary estimates of the prevalence were derived through random-effects meta-analysis and narrative synthesis. The review protocol has been registered with PROSPERO, CRD42021243934.Of 3973 records, we included 142 studies. In adults, the pooled prevalence of digital clubbing was 33.4% (95% confidence interval [CI], 16.6-52.8), 31.3% (95% CI, 22.4-41.1), 27% (95% CI, 9.4-49.5), and 22.8% (95% CI, 10.8-37.6) in subjects with intestinal diseases, interstitial lung diseases, infective endocarditis, and hepatic diseases, respectively. In children and adolescents, the pooled prevalence of digital clubbing was 29.1% (95% CI, 19.4-39.9), 23% (95% CI, 9.0-41.1), 19.5% (95% CI, 4.1-42.4), and 17.1% (95% CI, 9.5-26.5) in subjects with human immunodeficiency virus infection, hemoglobinopathies, cystic fibrosis, and tuberculosis. The pooled prevalence of HOA was 10.1% (95% CI, 2.0-23.1) in adults with cancers, and 5% (95% CI, 2.5-8.2) in children and adolescents with cystic fibrosis.In conclusion, the prevalence of digital clubbing varied across disease groups in both adults and children. Full-spectrum HOA was mostly reported in adults with liver disease and cancers, and in children and adolescents with cystic fibrosis.

Epidemiology of Sjögren Syndrome in Africa: A Scoping Review

BACKGROUND

The epidemiology of Sjögren syndrome (SS) has been extensively studied in America, Europe, and Asia.

OBJECTIVE

To summarize available data on the epidemiology of SS in Africa.

METHODS

MEDLINE, EMBASE, and African Journals Online were searched from inception up to May 17, 2020, to identify relevant articles. Data gleaned from these reports have been summarized narratively in this review.

RESULTS

Twenty-one hospital-based studies were included. These studies reported 744 cases of SS. The mean age at diagnosis varied between 28 and 73.6 years, and the female proportion ranged from 83.3% to 100%. There was no population-based incidence or prevalence. Among people with autoimmune and other rheumatic conditions, the frequency of primary SS was in the range 1.9% to 47.6%, whereas that of rheumatoid arthritis-associated secondary SS was in the range 4.3% to 100%. Sicca symptoms were the commonest features, with most frequently involved organs being joints, lungs, and neurological structures. Main autoantibodies were anti-Ro/SS antigen A, anti-La/SS antigen B, and antinuclear antibodies.

CONCLUSIONS

The epidemiology of SS is poorly characterized in Africa. Available data are broadly consistent with those from other populations. Extensive and high-quality research is urgently needed.

Oral antiviral treatments for COVID-19: opportunities and challenges

The use of antiviral COVID-19 medications can successfully inhibit SARS-CoV-2 replication and prevent disease progression to a more severe form. However, the timing of antiviral treatment plays a crucial role in this regard. Oral antiviral drugs provide an opportunity to manage SARS-CoV-2 infection without a need for hospital admission, easing the general burden that COVID-19 can have on the healthcare system. This review paper (i) presents the potential pharmaceutical antiviral targets, including various host-based targets and viral-based targets, (ii) characterizes the first-generation anti-SARS-CoV-2 oral drugs (nirmatrelvir/ritonavir and molnupiravir), (iii) summarizes the clinical progress of other oral antivirals for use in COVID-19, (iv) discusses ethical issues in such clinical trials and (v) presents challenges associated with the use of oral antivirals in clinical practice. Oral COVID-19 antivirals represent a part of the strategy to adapt to long-term co-existence with SARS-CoV-2 in a manner that prevents healthcare from being overwhelmed. It is pivotal to ensure equal and fair global access to the currently available oral antivirals and those authorized in the future.

Outcomes of pregnancy and associated factors in sub-Saharan African women with systemic lupus erythematosus: a scoping review

Objective

To scope and summarise available literature on the outcomes of pregnancy and associated factors in sub-Saharan African women with SLE.

Methods

Electronic databases and reference lists of retrieved articles were searched to identify relevant studies published from 1 January 2000 to 28 October 2019. Data were combined through narrative synthesis.

Results

We included four studies retrospectively reporting a total of 137 pregnancies in 102 women over a 26-year period. Mean age at conception ranged from 27.2 to 39.9 years. Kidney damage, the predominant organ manifestation before conception, was reported in 43 (42.2%) patients. Ninety-seven (70.8%) pregnancies resulted in 98 live births. SLE flares occurred in 44 (32.2%) pregnancies, mainly skin (20.4%) and renal (18.2%) flares. Major adverse pregnancy outcomes (APOs) were preterm birth 38.8%, low birth weight 29.8%, pregnancy loss 29.2% and pre-eclampsia 24.8%. The main factors associated with APOs were nephritis and SLE flares.

Conclusion

Over two-thirds of pregnancies resulted in live birth in this cohort of sub-Saharan African women with SLE. The main APOs and associated factors described in other parts of the world are also seen in this region, but with high rates of APOs. A large prospective multinational study is warranted for more compelling evidence.

Assessment of the efficacy of hemodialysis on uric acid clearance in a sub-Saharan African population at the end stage kidney disease

Background

Uricemia dramatically rises with the stage of chronic kidney disease (CKD) and correlates with its mortality. Hemodialysis (HD) being the most used treatment at the end stage in sub-Saharan Africa, we sought to evaluate its efficacy on the clearance of uric acid (UAc) when used alone and twice per week.

Methods

A cross-sectional study of all consenting patients with CKD stage 5 recruited at random during HD sessions in a reference Centre in Cameroon from January to April 2017. We collected socio-demographic data, relevant clinical information, HD related variables, and measured serum uric acid (SUA) levels before and after the dialysis to assess the uric acid clearance. A clearance between 65 and 80% and above 80% was considered as low and good efficacy of HD respectively. Statistical analysis was performed using SPSS version 21.0. Factors associated with HD efficacy were assessed using Fisher’s exact test and are presented with their odds ratios (OR) and 95% confidence levels.

Results

One hundred four patients (53 females) were included. The mean age was 49.9 ± 13.3 years. Hypertension (25%) and chronic glomerulonephritis (16%) were the main suspected etiologies of CKD. The median time on renal replacement therapy by HD was 3 years [1; 6]. The prevalence of hyperuricemia was 81.9%. The means of SUA levels were 78.8 ± 13.8 mg/L and 26.4 ± 6.6 mg/L respectively before and after dialysis. Mean SUA clearance was 66% ± 10%. The efficacy of HD on UAc was moderate in 92 (63.9%) and good in 2 (1.4%) patients. Excess weight (OR 0.4 [0.2; 0.9]) and Kt/Vurea < 1.2 (OR 0.1 [0.04; 0.2]) significantly reduces the efficacy of HD.

Conclusion

HD used alone for 2 sessions per week has a moderate efficacy on uric acid clearance in CKD. Therefore, we should improve the Kt/V (> 1.2), and combine HD to uric acid lowering drugs and diet modifications to increase its efficacy.

Coronavirus Disease 2019 (COVID-19) as a Multi-Systemic Disease and its Impact in Low- and Middle-Income Countries (LMICs)

Currently, the coronavirus disease 2019 (COVID-19) is the priority of the global health agenda. Since the first case was reported in Wuhan, China, this infection has continued to spread and has been considered as a pandemic by the World Health Organization (WHO) within 3 months of its outbreak. Several studies have been done to better understand the pathogenesis and clinical aspects of the disease. It appears that COVID-19 affects almost all body organs due to the direct effect of the virus and its induced widespread inflammatory response. This multi-systemic aspect of the disease has to be inculcated in COVID-19 management by health providers to improve patient outcomes. This strategy could help curb the burden of the disease especially in low- and middle-income countries (LMICs) like most African countries where the pandemic is at an “embryonic” stage.

Adult T-type lymphoblastic lymphoma presenting as hypercalcemic crisis and aplastic anemia: a case report

BACKGROUND

Hypercalcemia and aplastic anemia are two uncommon presentations of non-Hodgkin lymphoma that potentially worsen the disease prognosis. Although hypercalcemia has been reported in the B-cell subtypes and some T-cell subtypes of non-Hodgkin lymphoma, it has not been described in T-cell lymphoblastic lymphoma. The same applies to aplastic anemia, which is also not described in T-type lymphomas.

CASE PRESENTATION

We report a case of a 52-year-old Cameroonian man with acute kidney injury who presented with confusion, abdominal pain, constipation, polyuria, polydipsia, calciphylaxis, enlarged lymph nodes, tachycardia, and a blood pressure of 170/88 mmHg. Laboratory investigations revealed hypercalcemia (total/ionized 199.5/101.75 mg/L), normal serum phosphorus (40.20 mg/L), and a low intact parathyroid hormone (9.70 pg/ml). Complete blood count revealed pancytopenia. Peripheral blood smear confirmed thrombocytopenia but showed neither blasts nor flower cells. Bone marrow aspirate revealed hypocellularity with no blasts or fibrosis. Lymph node biopsy was suggestive of T-cell precursor lymphoma. T-lymphoblastic lymphoma presenting with hypercalcemic crisis and aplastic anemia was diagnosed, and the patient received the cyclophosphamide-doxorubicin-vincristine-prednisone protocol of chemotherapy together with filgrastim and whole-blood transfusion for aplastic anemia. The short-term outcome was fatal, however.

CONCLUSIONS

Severe hypercalcemia and aplastic anemia are potential paraneoplastic syndromes of adult T-type lymphoblastic lymphoma, with fatal short-term outcome.

Severe clinical immunodeficiency in a patient with human immunodeficiency virus infection and relatively high CD4 counts: a case report

BACKGROUND

The coexistence of neuromeningeal cryptococcosis and Kaposi's sarcoma is not surprising in a patient with human immunodeficiency virus infection and a low CD4 count, although it is rarely described. However, we describe such an association in a patient with human immunodeficiency virus infection and a relatively high CD4 count.

CASE PRESENTATION

A 41-year old Cameroonian woman presented to our hospital with subacute occipital headaches associated with photophobia, blurred vision, phonophobia, projectile vomiting, and tonic seizures. In her past history, there was an human immunodeficiency virus infection known for 12 years, for which she had been taking (with good compliance) tenofovir-lamivudine-efavirenz-based antiretroviral therapy for the same period of time. One month before the consultation, gastric Kaposi's sarcoma had been diagnosed, justifying the treatment with doxorubicin she had received. A clinical examination was unremarkable. A computed tomography scan of her brain was normal, and cerebrospinal fluid analysis revealed Cryptococcus neoformans. Her CD4 count was 353/mm3. Orally administered antifungal treatment with fluconazole (1200 mg/day) and flucytosine (1500 mg × 4/day) was started immediately, but she died on the sixth day of this treatment.

CONCLUSION

This clinical case shows that the coexistence of neuromeningeal cryptococcosis and gastric Kaposi's sarcoma is possible in all patients with human immunodeficiency virus infection, regardless of CD4 count.

Data on the epidemiology of heart failure in Sub-Saharan Africa

In Sub-Saharan Africa (SSA), chronic non-communicable diseases and cardiovascular diseases in particular, are progressively taking over infectious diseases as the leading cause of morbidity and mortality. Heart failure is a major public health problem in the region. We summarize here available data on the prevalence, aetiologies, treatment, rates and predictors of mortality due to heart failure in SSA.

Association of insulin treatment versus oral hypoglycaemic agents with diabetic retinopathy and its severity in type 2 diabetes patients in Cameroon, sub-Saharan Africa

BACKGROUND

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease associated with multiple macro and microvascular complications, diabetic retinopathy (DR) being the commonest one. Recent literature has reported an increased risk of DR with insulin use.

METHODS

We carried out a cross-sectional study at the Ophthalmology Department of the Douala General Hospital (DGH) during a 2-year period to explore the association between insulin treatment and both DR and its severity as compared with oral hypoglycemic agents (OHAs) in Cameroonian T2DM patients aged ≥35 years, and who were all screened for DR through eye examination including exhaustive retinal evaluation.

RESULTS

In total, medical files of 134 T2DM patients were analyzed. The frequency of DR was 54.1% among patients on OHA and 73.9% among those on insulin treatment, giving an overall frequency of 57.5%. There were significantly more OHA treated patients than insulin treated patients (82.8% vs. 17.2%, P<0.001). As expected, both the OHA and insulin groups were comparable by age, sex, duration of diabetes, past history of hypertension, alcohol misuse, and current tobacco smoking. DR was almost significantly more frequent in T2DM patients under insulin regimen than in patients under OHA [73.9% vs. 54.1%; odds ratio (OR) 2.4; 95% confidence interval (CI), 0.9-6.6; P=0.06]. Proliferative diabetic retinopathy (PDR) was significantly more observed in insulin treated patients than in OHA treated patients (34.8% vs. 15.3%; OR 2.95; 95% CI, 1.1-8; P=0.035). Irrespective of staging, the frequency of diabetic macular edema (DME) was significantly higher in the insulin group than in the OHA group (43.5% vs. 19.8%; OR 3.1; 95% CI, 1.2-8; P=0.019).

CONCLUSIONS

Compared with OHA, insulin therapy may be associated with DR, DR severity and DME in these T2DM sub-Saharan African patients.

Impact of a 12-week aerobic exercise training program on anthropometric and metabolic parameters of a group of type 2 diabetes Cameroonian women aged ≥50 years

BACKGROUND

We examined whether aerobic exercise could have an impact on anthropometric and metabolic parameters of type 2 diabetes mellitus (T2DM) Cameroonian women aged ≥50 years.

METHODS

We enrolled 23 T2DM Cameroonian women aged ≥50 years regularly followed at the National Obesity Center of Yaounde, Cameroon, in a 12-week aerobic exercise program monitored by a pedometer. Exercise intensity was progressively set between 55% and 75% of maximum heart rate. We measured weight, body mass index (BMI), fat, lean mass, visceral fat, maximum oxygen uptake, glycaemia and insulin tolerance index at baseline, after six and twelve weeks. A mixed ANOVA model was used to evaluate changes of outcome measures over time.

RESULTS

Total body weight was significantly reduced after 12 weeks (P<0.05), waist circumference after 6 and 12 weeks (P<0.05). There was an increase of the lean mass from 6 weeks (P<0.001) and a reduction of the mean visceral fat at 12 weeks (P<0.001). At the end of the program, the mean glycaemia was significantly decreased (P<0.05), and the maximum oxygen uptake was enhanced (P<0.05).

CONCLUSIONS

The 12-week aerobic exercise program improved the anthropometric and metabolic parameters as well as the aerobic capacity of T2DM Cameroonian women aged ≥50 years.

The highly neglected burden of resistant hypertension in Africa: a systematic review and meta-analysis

OBJECTIVE

The hypertension epidemic in Africa collectively with very low rates of blood pressure control may predict an incremented prevalence of resistant hypertension (RH) across the continent. The aim of this study was to determine the prevalence of RH and associated risk factors in Africa.

DATA SOURCES

We conducted a comprehensive search of electronic databases (PubMed, EMBASE, Africa Wide Information and Africa Index Medicus) completed by manual search of articles, regardless of language or publication date.

METHODS

We included studies which have reported the prevalence and/or risk factors for RH in Africa from inception to 19 May 2016. Forest plots were drawn to visualise the combined prevalence of RH and extent of statistical heterogeneity between studies.

RESULTS

Out of 259 retrieved studies, only 5 from Cameroon, Nigeria, Burkina Faso, Lesotho and Algeria with a total population of 4 068 patients were finally included in this review. There was no study from the Eastern part of Africa. Though the definition of RH was not similar across studies, its prevalence was respectively 11.7%, 4.9%, 14.6%, 14.3% and 19.0%, with an overall pooled prevalence of 12.1% (95% CI 8.0% to 17.7%). Potential risk factors were: non-compliance to treatment, ageing, male sex, dyslipidaemia, metabolic syndrome, previous cardiovascular events, physical inactivity and stress, but not excessive salt intake, alcohol and coffee ingestions. Moreover, diabetes, smoking, obesity and renal insufficiency yielded discrepant results.

CONCLUSIONS

There is a huge dearth of research on the epidemiology of RH in Africa. Thereby, an extensive study of RH prevalence and risk factors is still largely warranted to curtail the high and continuously increasing burden of hypertension across Africa.

Maternal hyperglycemia during labor and related immediate post-partum maternal and perinatal outcomes at the Yaoundé Central Hospital, Cameroon

BACKGROUND

Data on the prevalence and complications of gestational diabetes are very scarce in Cameroon. The aim of this study was to evaluate the uptake of screening for gestational diabetes and assess the immediate post-partum outcome of hyperglycemic parturient mothers and perinatal outcome of their babies.

METHODS

A prospective cohort study was held at the Maternity of the Yaoundé Central Hospital from March to June 2013. One hundred volunteer women in labor without overt diabetes mellitus and having fasted for 8 to 12 h were recruited. No intervention was given. A clinical examination was done and capillary glucose recorded. Parturient women were categorized into two groups (hyperglycemic and non-hyperglycemic subjects) based on glycemia results interpreted according to the International Association of Diabetes and Pregnancy Study Groups. Mothers' clinical examination was repeated and neonates examined immediately after delivery. Perinatal outcomes associated with maternal hyperglycemia during labor were assessed using relative risks. A p value <0.05 was considered statistically significant.

RESULTS

One hundred women with a mean age of 27 (SD 6) years were recruited. Of them, 22 (22 %) had already been screened for gestational diabetes at baseline. Thirty-one (31 %) were diagnosed with hyperglycemia during labor, and this condition was highly associated with macrosomia in neonates (RR = 8.9, 95 % CI 2.70-29.32; p < 0.001). Other complications associated with maternal hyperglycemia during labor were perineal tears, cesarean section, and intrauterine fetal death, though the association was not statistically significant.

CONCLUSIONS

The main finding of this study is that maternal hyperglycemia during labor is highly associated with macrosomia in neonates. About a third of mothers were concerned with hyperglycemia during labor, and gestational diabetes was insufficiently screened in this series.

Effect of low-dose spironolactone on resistant hypertension in type 2 diabetes mellitus: a randomized controlled trial in a sub-Saharan African population

Background

Low-dose spironolactone has been proven to be effective for resistant hypertension in the general population, but this has yet to be confirmed in type 2 diabetic (T2DM) patients. We assessed the efficacy of a low-dose spironolactone on resistant hypertension in a sub-Saharan African population of T2DM patients from Cameroon.

Methods

This was a four-week single blinded randomized controlled trial in 17 subjects presenting with resistant hypertension in specialized diabetes care units in Cameroon. They were randomly assigned to treatment with a daily 25 mg of spironolactone (n = 9) or to an alternative antihypertensive regimen (n = 8), on top of any ongoing regimen and prevailing lifestyle prescriptions. They were seen at the start of the treatment, then 2 and 4 weeks later. The primary outcome was change in office and self-measured blood pressure (BP) during follow-up, and secondary outcomes were changes in serum potassium, sodium, and creatinine levels.

Results

Compared with alternative treatment, low-dose spironolactone was associated with significant decrease in office systolic BP (−33 vs. −14 mmHg; p = 0.024), and in diastolic BP (−14 vs. −5 mmHg; p = 0.006). After 1 month of spironolactone, all the patients were controlled based on BP below 130/80 mmHg, with significant office BP reduction from 158 ± 17/86 ± 11 to 125 ± 11/72 ± 8, vs. 158 ± 8/94 ± 8 to 144 ± 17/89 ± 12 mmHg in the alternative treatment group. There was no significant variation in sodium and creatinine levels in both groups, but a mild increase of potassium levels in the spironolactone group.

Interpretation

Add-on low-dose spironolactone was effective in reducing BP to optimal levels in T2DM Cameroonian patients despite mild increase in serum potassium.

Trial registration ClinicalTrials.gov Identifier NCT02426099. Date of registration April 2015

Hypertension prevalence, incidence and risk factors among children and adolescents in Africa: a systematic review and meta-analysis protocol

INTRODUCTION

The African adult population is facing a growing epidemic of hypertension. Establishment of accurate epidemiological data on hypertension in African children and adolescents may have important implications for hypertension preventive strategies in Africa.

METHODS AND ANALYSIS

This systematic review and meta-analysis will follow the MOOSE Guidelines. Relevant abstracts published in English/French from 1 January 1985 to 31 July 2015 will be searched in PubMed, Google Scholar and Online African journals. Full texts of eligible studies will then be accessed through PubMed, Google Scholar, HINARI and the respective journals' websites. Relevant unpublished papers and conference proceedings will also be checked. Data will be analysed using R statistical software. The study-specific estimates will be pooled through a random-effects meta-analysis model to obtain an overall summary estimate of the prevalence/incidence of hypertension across studies. Also, we will assess the association between risk factors and hypertension. Heterogeneity of studies will be evaluated by the χ(2) test on Cochrane's Q statistic. Funnel plots analysis and Egger's test will be done to detect publication bias. Results will be presented by geographic region (central, eastern, northern, southern and western Africa). A p value less than 0.05 will be considered significant for factors that predicted hypertension.

ETHICS AND DISSEMINATION

The current study is based on published data, and thus ethical approval is not required. This systematic review and meta-analysis is expected to serve as input for designing early life preventive and control strategies, and as a guide for future research based on existing gaps. The final report of the systematic review in the form of a scientific paper will be published in peer-reviewed journals. Findings will further be presented at conferences and submitted to relevant health authorities.

TRIAL REGISTRATION NUMBER

CRD42015019029.

Therapeutic potential of folic acid supplementation for cardiovascular disease prevention through homocysteine lowering and blockade in rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a chronic inflammatory disease that preferentially affects joints, and characterized by an approximately two-fold increased risk of cardiovascular diseases compared with the general population. Beyond classical cardiovascular risk factors, systemic inflammatory markers are primarily involved. Hence, anti-inflammatory strategies such as homocysteine-lowering interventions are warranted. Indeed, hyperhomocysteinemia is commonly found in RA patients as a result of both genetic and non-genetic factors including older age, male gender, disease-specific features and disease-modifying antirheumatic drugs. Most importantly in the pathophysiology of hyperhomocysteinemia and its related cardiovascular diseases in RA, there is a bi-directional link between immuno-inflammatory activation and hyperhomocysteinemia. As such, chronic immune activation causes B vitamins (including folic acid) depletion and subsequent hyperhomocysteinemia. In turn, hyperhomocysteinemia may perpetrate immuno-inflammatory stimulation via nuclear factor ƙappa B enhancement. This chronic immune activation is a key determinant of hyperhomocysteinemia-related cardiovascular diseases in RA patients. Folate, a homocysteine-lowering therapy could prove valuable for cardiovascular disease prevention in RA patients in the near future with respect to homocysteine reduction along with blockade of subsequent oxidative stress, lipid peroxidation, and endothelial dysfunction. Thus, large scale and long term homocysteine-lowering clinical trials would be helpful to clarify the association between hyperhomocysteinemia and cardiovascular diseases in RA patients and to definitely state conditions surrounding folic acid supplementation. This article reviews direct and indirect evidence for cardiovascular disease prevention with folic acid supplementation in RA patients.

Is air pollution a risk factor for rheumatoid arthritis?

Rheumatoid arthritis is a chronic inflammatory debilitating disease triggered by a complex interaction involving genetic and environmental factors. Active smoking and occupational exposures such as silica increase its risk, suggesting that initial inflammation and generation of rheumatoid arthritis-related autoantibodies in the lungs may precede the clinical disease. This hypothesis paved the way to epidemiological studies investigating air pollution as a potential determinant of rheumatoid arthritis. Studies designed for epidemiology of rheumatoid arthritis found a link between traffic, a surrogate of air pollution, and this disease. Furthermore, a small case–control study recently found an association between wood smoke exposure and anticyclic citrullinated protein/peptide antibody in sera of patients presenting wood-smoke-related chronic obstructive pulmonary disease. However, reports addressing impact of specific pollutants on rheumatoid arthritis incidence and severity across populations are somewhat conflicting. In addition to the link reported between other systemic autoimmune rheumatic diseases and particulate matters/gaseous pollutants, experimental observation of exacerbated rheumatoid arthritis incidence and severity in mice models of collagen-induced arthritis after diesel exhaust particles exposure as well as hypovitaminosis D-related autoimmunity can help understand the role of air pollution in rheumatoid arthritis. All these considerations highlight the necessity to extend high quality epidemiological researches investigating different sources of atmospheric pollution across populations and particularly in low-and-middle countries, in order to further explore the biological plausibility of air pollution’s effect in the pathogenesis of rheumatoid arthritis. This should be attempted to better inform policies aiming to reduce the burden of rheumatoid arthritis.

Targeting Household Air Pollution for Curbing the Cardiovascular Disease Burden: A Health Priority in Sub-Saharan Africa

Household air pollution (HAP) is a major public health problem, particularly in sub-Saharan Africa where most of the populations still rely on solid fuels for cooking, heating, and lighting. This narrative review highlights the direct and indirect evidence of the important role of HAP in cardiovascular disease, especially in sub-Saharan African countries where highest rates of major cardiovascular disease and death are observed, and thus provides ample reason for promotion of preventive interventions to reduce HAP exposures in the region. There is an urgent need for efficient strategies to educate populations on the health issues associated with this health hazard, to provide affordable clean cooking energy for poor people and to promote improved household ventilation. High-quality data on household energy practices and patterns of HAP and related health issues are still needed for efficient policy making in this region.

Osteoprotegerin in relation to insulin resistance and blood lipids in sub-Saharan African women with and without abdominal obesity

BACKGROUND

Osteoprotegerin (OPG), a soluble member of the tumor necrosis factor receptor superfamily that inhibits bone resorption, has been suggested as a potential marker of cardiovascular risk. This study aimed to assess the relationship between insulin resistance, lipid profile and OPG levels in obese and non-obese sub-Saharan African women.

METHODS

Sixty obese (44) and non-obese (16) volunteer women aged 18 to 40 years were recruited in this cross-sectional study. Their clinical (age, height, weight, waist circumference, systolic and diastolic blood pressures) and biochemical parameters (fasting blood glucose, total cholesterol, high density lipoprotein-cholesterol (HDL-C)) were measured using standard methods. Insulin levels were measured using an electrochemiluminescence immunoassay, while OPG levels were measured using the ELISA technique. Low density lipoprotein-cholesterol (LDL-C), body mass index (BMI) and Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) were calculated using standard methods. Abdominal obesity was defined as a waist circumference ≥ 80 cm.

RESULTS

OPG levels were higher in obese than in normal subjects, though the difference was not significant (p = 0.9). BMI, waist circumference, percent body fat and systolic blood pressure were significantly higher in obese than in non-obese subjects (p < 0.05). In these subjects, only age significantly correlated with OPG levels (r = 0.831, p = 0.003), while none of the anthropometric nor metabolic parameter did, even after adjustment for age. In obese subjects, OPG levels fairly correlated with HDL-C (r = 0.298, p = 0.058), and significantly correlated with HOMA-IR (r = -0.438, p = 0.018). After adjustment for age, OPG levels remained negatively correlated to HOMA-IR (r = -0.516, p = 0.020) and LDL-C (r = -0.535, p = 0.015) and positively correlated to HDL-C (r = 0.615, p = 0.004). In multiple linear regression analysis, age was a main determinant of OPG levels in non-obese (β = 0.647, p = 0.006) and obese (β = 0.356, p = 0.044) women. HDL-C was also associated to OPG levels in obese women (β = 0.535, p = 0.009).

CONCLUSION

The positive correlation of OPG with HDL-C and HOMA-IR, and its negative correlation with LDL-C suggest that it may be a marker of insulin sensitivity/resistance and atherogenic risk in obese African women.