Hypertension in older adults in Africa: A systematic review and meta-analysis.
ABSTRACT: BACKGROUND:Hypertension is the leading driver of cardiovascular disease deaths in Africa. Its prevalence is highest in older populations. Yet, this group has received little attention in many African countries. We conducted a systematic review and meta-analysis (PROSPERO registration: CRD42017056474) to estimate the prevalence of hypertension in older adults living in Africa. METHODS:We searched grey literature and major electronic databases including PubMed and Embase for population-based studies and published between 1 January 1980 to 28 May 2018 reporting the prevalence of hypertension for adults aged ?50 years living in Africa. We employed a random effects model to estimate the pooled prevalence across included studies. FINDINGS:We screened 10,719 articles and retrieved 103 full-text articles to evaluate for inclusion in the review. Thirty-four unique studies providing 37 data points on 43,025 individuals in 15 African countries were analyzed. The prevalence of hypertension ranged from 22.3% to 90.0% from the individual studies while the overall pooled prevalence was 57.0% (95% CI 52%-61%). The prevalence was not statistically significantly different by sex, residence, or African sub-region. In individual studies, older age and overweight/obesity were independently associated with hypertension. Twenty-nine (78%) data points were deemed to be of low- or moderate-risk of bias. Eliminating high-risk bias studies made little difference to the pooled estimate of hypertension. Sensitivity analyses, omitting one study at a time, identified three studies with significant but relatively small impact on the pooled estimate. We observed substantial heterogeneity (I2 = 98.9%) across the studies which was further explored by meta-regression analyses. Overall, the GRADE assessment suggested moderate quality evidence in the results. CONCLUSION:The persistent high prevalence of hypertension among older adults in Africa, even in rural populations warrants more attention to the cardiovascular health of this group by public health authorities.
Project description:The health of older persons has not been a major priority in many African countries. Hypertension is one of the common health problems of older persons. However, there is little information on the prevalence of hypertension in older adults in Africa. This is in spite of the fact that Africa has the highest age-standardized prevalence of hypertension in the world. We therefore present this protocol to conduct a systematic review and meta-analysis on the prevalence of hypertension and the level of its awareness among older persons living in Africa.Major databases (EMBASE, MEDLINE, Academic Search Complete, CINAHL, PsycINFO) and unpublished literature will be searched to identify population-based studies on hypertension in adults aged 50 years and older living in Africa. Eligible articles are those which use the 140/90-mmHg cutoff to diagnose hypertension and were published from 1980 to present. We will exclude subjects in restricted environments such as patients and refugees. Articles will be independently evaluated by two reviewers to determine if they meet the inclusion criteria. They will also evaluate the quality of included studies using a validated tool by Hoy and colleagues for prevalence studies. The main outcome is the prevalence of hypertension while the explanatory variables include demographic, socio-economic, dietary, lifestyle and behavioural factors. Effect sizes in bivariate and multivariate analyses will be presented as odds or prevalence ratios. We will explore for heterogeneity of the standard errors across the studies, and if appropriate, we will perform a meta-analysis using a random-effects model to present a summary estimate of the prevalence of hypertension in this population.The estimates of the prevalence, the risk factors and the level of awareness of hypertension could help in galvanizing efforts at prioritizing the cardiovascular health of older persons in Africa.PROSPERO CRD42017056474.
Project description:BACKGROUND:An estimated 55% of older adults in Africa have systemic hypertension, a major risk factor for stroke, heart failure and dementia in the region. The risk factors associated with hypertension in this population group in Africa have not been systematically evaluated. We, therefore, undertook a systematic review to identify these risk factors. METHODS:We searched for population-based studies of adults aged ≥50 years living in Africa and reporting an estimate of hypertension and associated risk factors. We included articles published in any language between January 1980 and May 2018 using a comprehensive search strategy. We extracted data including the sample characteristics, prevalence of hypertension and risk factors with their effect sizes. RESULTS:From an initial 10,719 records, we retained 63 eligible full text articles for review out of which we analyzed 23 studies made up of 19 primary and four multiple publications which had data on risk factors from bivariate or multivariable analysis. The primary studies, published from 2010 to 2018, involved a total of 30,500 participants in 12 different countries with mean ages ranging from 62.7 ± 9 years to 76.9 ± 8.4 years. Through narrative synthesis, we found consistent determinants of hypertension (overweight/obesity and history of stroke), less consistent but frequent determinants (including older age group, female sex and urban residence), inconsistent determinants (including education, wealth index, alcohol intake and physical activity) and nonsignificant covariates (marital status and having health insurance). Overall, the highest adjusted odds ratios were those associated with obesity and history of stroke. CONCLUSION:The key determinants of systemic hypertension in older adults in Africa are older age group, overweight/obesity, history of stroke and female sex. Health programmes should promote weight reduction throughout the life course, including during the middle and older age of African adults.
Project description:BACKGROUND:Asthma is one of the neglected diseases in Africa with a high prevalence. Allergic fungal diseases have been reported to complicate asthma progression and treatment outcomes. However, data about fungal asthma and its associated complications are limited in Africa. We aimed to estimate the burden of fungal asthma among adults and children in Africa using a systematic review. METHODS:We first engaged the Institute for Health Metrics and Evaluation (IHME) to highlight the trend in morbidity and mortality attributed to asthma in Africa. We then searched PubMed, HINARI and Google Scholar for all studies of any design focusing on fungal asthma in any African country. Languages were restricted to English and French, but not year of publication. We estimated the weighted prevalence of allergic fungal infections among asthmatics with a 95% CI and pooled the results using a random effects model. This study is registered with PROSPERO, number CRD42019117319. RESULTS:The IHME data showed that there has been a gradual increase in morbidity and mortality due to asthma in African adults with a prevalence of 4%. Our search retrieved 5233 citations. We retained 20 studies that met our selection criteria. These were from 13 African countries published between 1967 and 2018. There were eight cross-sectional studies and twelve review articles. The average asthma prevalence in Africa was 6% from these studies. The prevalence of fungal sensitisation was relatively high (3-52%) in the asthmatic population with an average of 28% and a pooled estimate of 23.3%, mostly due to Aspergillus species. Prevalence of Allergic bronchopulmonary apsergillosis was estimated at 1.6-21.2%. Diagnosis of fungal allergy was mostly made by skin prick tests. There was no data on the use of medication to manage fungal asthma. None of the studies evaluated the association between fungal allergy and asthma severity. Data were lacking in children. CONCLUSION:There is a high prevalence of fungal sensitization among Africans with asthma. Fungal asthma is a significant problem in Africa but there remains a paucity of data on the epidemiology and associated complications. There is urgent need for national epidemiological studies to estimate the actual burden of fungal asthma in Africa.
Project description:OBJECTIVES:While increasing attention is paid to the rising prevalence of chronic diseases in Africa, there is little focus on chronic kidney disease (CKD). This systematic review assesses CKD burden among the general population and high-risk groups on the entire African continent. DESIGN, SETTING AND PARTICIPANTS:We searched Medline and PubMed databases for articles published between 1 January 1995 and 7 April 2017 by sensitive search strategies focusing on CKD surveys at the community level and high-risk groups. In total, 7918 references were evaluated, of which 7766 articles were excluded because they did not meet the inclusion criteria. Thus, 152 studies were included in the final analysis. OUTCOME MEASUREMENT:The prevalence of CKD in each study group was expressed as a range and pooled prevalence rate of CKD was calculated as a point estimate and 95%?CI. No meta-analysis was done. Data were presented for different populations. RESULTS:In the community-level studies, based on available medium-quality and high-quality studies, the prevalence of CKD ranged from 2% to 41% (pooled prevalence: 10.1%; 95%?CI 9.8% to 10.5%). The prevalence of CKD in the high-risk groups ranged from 1% to 46% (pooled prevalence: 5.6%; 95%?CI 5.4% to 5.8%) in patients with HIV (based on available medium-quality and high-quality studies), 11%-90% (pooled prevalence: 24.7%; 95%?CI 23.6% to 25.7%) in patients with diabetes (based on all available studies which are of low quality except four of medium quality) and 13%-51% (pooled prevalence: 34.5%; 95?% CI 34.04% to 36%) in patients with hypertension (based on all available studies which are of low quality except two of medium quality). CONCLUSION:In Africa, CKD is a public health problem, mainly attributed to high-risk conditions as hypertension and diabetes. The poor data quality restricts the validity of the findings and draws the attention to the importance of designing future robust studies.
Project description:This meta-analysis was undertaken to estimate the prevalence of diabetic nephropathy and its association with hypertension in diabetics of sub-Saharan African countries.A total of 27 studies were included for the meta-analysis. The pooled overall prevalence of diabetic nephropathy was 35.3 (95% CI 27.46-43.14). In sub-group analyses by types of diabetes and regions, for instance, the prevalence was 41.4% (95% CI 32.2-50.58%) in type-2 diabetes mellitus and 29.7% (95% CI 14.3-45.1%) in Eastern Africa. Pooled point estimates from included studies revealed an increased risk of diabetic nephropathy with hypertension compared to without hypertension (OR?=?1.67, 95% CI 1.31, 2.14). Diabetic nephropathy is a common complication in diabetic patients. Diabetic nephropathy complication is significantly higher in hypertensive patients. A preventive strategy should be adopted or planned to reduce diabetes mellitus and its complication of neuropathy, particularly in hypertensive.
Project description:Background:Gestational diabetes mellitus (GDM) is a major public health problem and threat to maternal and child health in Africa. No prior review has been conducted in Africa using the updated GDM diagnostic criteria. Therefore, this review aimed to estimate the pooled prevalence and determinants of GDM in Africa by using current international diagnostic criteria. Methods:A systematic review and meta-analysis was conducted by comprehensive search of the published studies in Africa. Electronic databases (PubMed, Scopus, Cochrane Library, EMBASE, Google Scholar, CINAHL, Web of Science, Science direct and African Journals Online) were searched using relevant search terms. Data were extracted on an excel sheet and Stata/ SE 14.0 software was used to perform the meta-analysis. Heterogeneity of included studies were assessed using I 2 and Q test statistics. I2?>?50% and Q test with its respective p-value <?0.05 were suggestive for the presence of a significant heterogeneity. Publication bias was assessed using the Egger's regression test and funnel plot. Subgroup and sensitivity analyses were done. A random effects model was used to estimate the pooled prevalence of GDM and odds ratio (OR) with 95% confidence interval (CI). Result:A total of 23 studies were included in the final analysis. The pooled prevalence of GDM in Africa was 13.61% (95% CI: 10.99, 16.23; I2?=?96.1%), and 14.28% (95% CI, 11.39, 17.16; I2?=?96.4%) in the sub-Saharan African region. The prevalence was highest in Central Africa 20.4% (95% CI, 1.55, 38.54), and lowest in Northern Africa 7.57% (95% CI, 5.89, 9.25) sub- regions. Overweight and obesity, macrosomia, family history of diabetes, history of stillbirth, history of abortion, chronic hypertension and history of previous GDM had positively associated with GDM. Conclusions:The prevalence of GDM is high in Africa. Being overweighed and/or obese, ever had macrocosmic baby, family history of diabetes, history of stillbirth, history of abortion or miscarriage, chronic hypertension and history of previous GDM were factors associated with GDM. Preventing overweighed and obese, giving due attention to women having high-risk cases for GDM in pregnancy are strongly recommended to mitigate the burden. Systematic review registration:PROSPERO (2018:CRD42018116843).
Project description:BACKGROUND:Diabetes mellitus (DM) is a global health care problem that can impose a substantial economic burden. Diabetic peripheral neuropathy (DPN) is a common microvascular complication of DM that increases the potential for morbidity and disability due to ulceration and amputation. Though there is a significant amount of variation in the primary studies on DM regarding the prevalence of DPN in Africa. Hence, this study was aimed to estimate the overall prevalence of DPN in DM patients in Africa. METHODS:PubMed, Scopus, Google Scholar, African Journals OnLine, WHO African Library, and the Cochrane Review were systematically searched online to retrieve related articles. The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines was followed. Heterogeneity across the included studies was evaluated by the inconsistency index (I2). Publication bias was examined by funnel plot and Egger's regression test. The random-effect model was fitted to estimate the pooled prevalence of diabetic peripheral neuropathy among patients in Africa. The meta-analysis was performed using the STATA™ Version 14 software. RESULTS:Twenty-three studies which includes 269,691 participants were included in the meta-analysis. The overall pooled prevalence of diabetic peripheral neuropathy was 46% (95% CI:36.21-55.78%). Based on the subgroup analysis, the highest prevalence of diabetic peripheral neuropathy in DM patients was reported in West Africa at 49.4% (95% CI: 32.74, 66.06). CONCLUSION:This study revealed that the overall prevalence of diabetic peripheral neuropathy is relatively high in Africa. Hence, DPN needs situation-based interventions and preventive strategies, which are specific to the country. Further meta-analysis is needed to identify associated factors for the occurrence of diabetic peripheral neuropathy.
Project description:BACKGROUND:Despite the high prevalence of epilepsy in sub-Saharan Africa and the established relationship between depression and epilepsy, the extent of comorbid epilepsy and depression in the region is still poorly understood. The objective of this systematic review and meta-analysis is to address this gap in the literature by determining the pooled prevalence of depression among epileptic patients in sub-Saharan Africa. METHODS:A systematic desk review and electronic web-based search of PubMed, Google Scholar, EMBASE, PsycINFO and the World Health Organization's Hinari portal (which includes the SCOPUS, African Index Medicus, and African Journals Online databases) conducted from December 2, 2017 to February 30, 2018, identified peer-reviewed, original research articles and doctoral dissertations using pre-defined quality and inclusion criteria. Relevant data were extracted and descriptive summaries of the studies presented in tabular form. The I2 statistic was used to assess heterogeneity across studies. Funnel plot asymmetry and Egger's tests were used to check for publication bias and the methodological quality of the included studies were assessed using the scale developed by Hoy and colleagues. The pooled prevalence of comorbidity at a 95% confidence interval (CI) was determined by applying a trim and fill analysis in a random-effects model. RESULTS:Our search identified 167 studies, of which 14 original research articles and two doctoral dissertations reporting on case-control and cross-sectional studies were eligible for inclusion in the final analysis. The pooled estimate of prevalence of depression among patients with epilepsy was 32.71% (95% CI: 25.50-39.91%). Regional sub-group analysis found that the pooled prevalence in East Africa was 34.52% (95% CI: 23.53-45.51%) and 29.69% (95% CI: 22.7-36.68%) in Southern and West Africa. The odds of depression among epileptic patients receiving polytherapy were 2.65 higher than in those receiving monotherapy (95% CI: 1.49-4.71, I2 = 79.1%, p < 0.05). CONCLUSION:Our findings indicate high comorbidity in sub-Saharan Africa and suggest that it may be more prevalent there than elsewhere. Comorbidity is statistically associated with polytherapy in the studies reviewed. Given the high levels of comorbidity in the region, more attention should be paid to incorporating depression screening and treatment into existing epilepsy programs and to revising treatment guidelines on comorbid depression to reduce polytherapy.
Project description:Background:Metabolic syndrome (MetS) is a major public health problem in Sub-Saharan Africa. We systematically reviewed the literature towards estimating the prevalence of MetS among apparently "healthy" Ghanaian adults. Methods:We searched PubMed, Web of Science, Scopus, Africa Journals Online, African Index Medicus, and Google scholar as well as the websites of the Ministry of Health and Ghana Health service through September 2016. Only studies conducted among apparently "healthy" (no established disease, e.g., diabetes and hypertension) adults aged ? 18 years were considered. Only studies that utilised the National Cholesterol Education Program Adult Treatment Panel (NCEP-ATP), World Health Organization (WHO), or International Diabetes Federation (IDF) classifications for MetS were included. Results:Data from nine studies involving 1,559 individuals were pooled. The prevalence of MetS based on NCEP-ATP, WHO, and IDF classifications was 12.4% (95% confidence interval [CI] = 8.3-17.4%), 6.0% (95% CI = 1.4-13.1%), and 21.2% (95% CI = 12.4-30.9), respectively. Prevalence of MetS was higher among women than men. Conclusion:Among a population of adult Ghanaians deemed "healthy," there is a high prevalence of MetS. Preventive measures are required to address the risk components of MetS such as obesity and hypertension which are rapidly rising in Ghana.
Project description:The burden of hypertension is high in Africa, and due to rapid population growth and ageing, the exact burden on the continent is still far from being known. We aimed to estimate the prevalence and awareness rates of hypertension in Africa based on the cut off "?140/90 mm Hg".We conducted a systematic search of Medline, EMBASE and Global Health. Search date was set from January 1980 to December 2013. We included population-based studies on hypertension, conducted among people aged ?15 years and providing numerical estimates on the prevalence of hypertension in Africa. Overall pooled prevalence of hypertension in mixed, rural and urban settings in Africa were estimated from reported crude prevalence rates. A meta-regression epidemiological modelling, using United Nations population demographics for the years 1990, 2000, 2010 and 2030, was applied to determine the prevalence rates and number of cases of hypertension in Africa separately for these four years.Our search returned 7680 publications, 92 of which met the selection criteria. The overall pooled prevalence of hypertension in Africa was 19.7% in 1990, 27.4% in 2000 and 30.8% in 2010, each with a pooled awareness rate (expressed as percentage of hypertensive cases) of 16.9%, 29.2% and 33.7%, respectively. From the modelling, over 54.6 million cases of hypertension were estimated in 1990, 92.3 million cases in 2000, 130.2 million cases in 2010, and a projected increase to 216.8 million cases of hypertension by 2030; each with an age-adjusted prevalence of 19.1% (13.9, 25.5), 24.3% (23.3, 31.6), 25.9% (23.5, 34.0), and 25.3% (24.3, 39.7), respectively.Our findings suggest the prevalence of hypertension is increasing in Africa, and many hypertensive individuals are not aware of their condition. We hope this research will prompt appropriate policy response towards improving the awareness, control and overall management of hypertension in Africa.