Juliet Addo

Hypertension In Sub-Saharan Africa A Systematic Review

Hypertension is an important public health challenge worldwide. Information on the burden of disease from hypertension is essential in developing effective prevention and control strategies. An up-to-date and comprehensive assessment of the evidence concerning hypertension in sub-Saharan Africa is lacking. A literature search of the PUBMED database was conducted and supplemented by a manual search of bibliographies of retrieved articles. The search was restricted to population based studies on hypertension in sub-Saharan Africa published between January 1975 and May 2006. Data were extracted after a standard protocol and using standard data collection forms. Thirty-seven publications met the inclusion criteria. The prevalence of hypertension varied extensively between and within studies. Prevalence of hypertension was higher in urban than rural studies in all studies that covered both types of area, and also increased with increasing age in most studies. In most studies less than 40% of people with blood pressure above the defined normal range had been previously detected as hypertensive. Of people with previously diagnosed hypertension, less than 30% were on drug treatment in most studies, and less than 20% had blood pressure within the defined normal range. Hypertension is of public health importance in sub-Saharan Africa, particularly in urban areas, with evidence of considerable under-diagnosis, treatment, and control. There is an urgent need to develop strategies to prevent, detect, treat, and control hypertension effectively in the African region.

Socioeconomic Status and Stroke An Updated Review

Background and Purpose— Rates of stroke incidence and mortality vary across populations with important differences between socioeconomic groups worldwide. Knowledge of existing disparities in stroke risk is important for effective stroke prevention and management strategies. This review updates the evidence for associations between socioeconomic status and stroke. Summary of Review— Studies were identified with electronic searches of MEDLINE and EMBASE databases (January 2006 to July 2011) and reference lists from identified studies were searched manually. Articles reporting the association between any measure of socioeconomic status and stroke were included. Conclusions— The impact of stroke as measured by disability-adjusted life-years lost and mortality rates is >3-fold higher in low-income compared with high- and middle-income countries. The number of stroke deaths is projected to increase by >30% in the next 20 years with the majority occurring in low-income countries. Higher incidence of stroke, stroke risk factors, and rates of stroke mortality are generally observed in low compared with high socioeconomic groups within and between populations worldwide. There is less available evidence of an association between socioeconomic status and stroke recurrence or temporal trends in inequalities. Those with a lower socioeconomic status have more severe deficits and are less likely to receive evidence-based stroke services, although the results are inconsistent. Poorer people within a population and poorer countries globally are most affected in terms of incidence and poor outcomes of stroke. Innovative prevention strategies targeting people in low socioeconomic groups are required along with effective measures to promote access to effective stroke interventions worldwide.

Cardiovascular disease, diabetes and established risk factors among populations of sub-Saharan African descent in Europe: a literature review

BackgroundMost European countries are ethnically and culturally diverse. Globally, cardiovascular disease (CVD) is the leading cause of death. The major risk factors for CVD have been well established. This picture holds true for all regions of the world and in different ethnic groups. However, the prevalence of CVD and related risk factors vary among ethnic groups.MethodsThis article provides a review of current understanding of the epidemiology of vascular disease, principally coronary heart disease (CHD), stroke and related risk factors among populations of Sub-Sahara African descent (henceforth, African descent) in comparison with the European populations in Europe.ResultsCompared with European populations, populations of African descent have an increased risk of stroke, whereas CHD is less common. They also have higher rates of hypertension and diabetes than European populations. Obesity is highly prevalent, but smoking rate is lower among African descent women. Older people of African descent have more favourable lipid profile and dietary habits than their European counterparts. Alcohol consumption is less common among populations of African descent. The rate of physical activity differs between European countries. Dutch African-Suriname men and women are less physically active than the White-Dutch whereas British African women are more physically active than women in the general population. Literature on psychosocial stress shows inconsistent results.ConclusionHypertension and diabetes are highly prevalent among African populations, which may explain their high rate of stroke in Europe. The relatively low rate of CHD may be explained by the low rates of other risk factors including a more favourable lipid profile and the low prevalence of smoking. The risk factors are changing, and on the whole, getting worse especially among African women. Cohort studies and clinical trials are therefore needed among these groups to determine the relative contribution of vascular risk factors, and to help guide the prevention efforts. There is a clear need for intervention studies among these populations in Europe.

Delay in Presentation After an Acute Stroke in a Multiethnic Population in South London: The South London Stroke Register

Background Delayed presentation to hospital after an acute stroke is a major explanation given for low thrombolysis rates. This study aimed to investigate the factors associated with delays in presentation after an acute stroke and changes after a mass media campaign. Methods and Results Data were from a population-based study involving 1392 patients with first-ever strokes between 2002 and 2010 in a multiethnic South London population. Associations were determined between prehospital delay (≥3 hours) and variables of interest, including ethnicity, by using multivariate logistic regression analyses. Differences in prehospital delay and thrombolysis rates were determined for the period immediately before and after the FAST mass media campaign (2007/2008 versus 2009/2010). The median (Q1 to Q3) time to presentation was 4.73 (1.55 to 12.70) hours, and 550 (39.5%) presented within 3 hours of symptom onset. In multivariate analysis, patients of black ethnicity had increased odds of delay (odds ratio: 1.63; 95% confidence interval, 1.11 to 2.38), whereas those with more severe strokes characterized by a higher National Institutes of Health Stroke Scale score (odds ratio: 0.35; 95% confidence interval, 0.20 to 0.61) had reduced odds of delay. There was no difference in the proportion of patients who arrived within 3 hours (P=0.30) in the period immediately before and after the FAST campaign (40.7% in 2007/2008 versus 44.9% in 2009/2010). Among patients with ischemic stroke, 119 (11.0%) received thrombolysis between 2002 and 2010, with no difference observed between the pre- and postcampaign periods (16.9% versus 16.4%). Conclusion Significant delays in seeking care after stroke still occur in this population despite efforts to increase public awareness. Future educational programs must identify and specifically address factors that influence behavior and should target those at higher risk of delay. (J Am Heart Assoc. 2012;1:e001685 doi: 10.1161/JAHA.112.001685.)

Review of community-based interventions for prevention of cardiovascular diseases in low- and middle-income countries

Background. An increasing burden of cardiovascular disease (CVD) is occurring in low- and middle-income countries (LMICs) as a result of urbanisation and globalisation. Low rates of awareness and treatment of risk factors worsen the prognosis in these settings. Prevention of CVD is proven to be cost effective and should be the main intervention. Insight into prevention programmes in LMIC is important in addressing the rising levels of these diseases. Objective. To evaluate the effectiveness of the community-based interventions for CVD prevention programmes in LMIC. Design. A literature review with searches in the databases of PubMed, EMBASE, CINAHL, LILACS, African Index Medicus and Google Scholar between 1990 and May 2012. Results. Twenty-six studies involving population-based and high-risk interventions have been included in this review. The content of the population intervention was mainly health promotion through media and health education, and the high-risk approach focused often on education of patients, training of health care providers and implementing treatment guidelines. A few studies had a single intervention on exercising or salt reduction. Most studies showed a significant reduction of cardiovascular risk ranging from lifestyle changes on diet, smoking and alcohol to biomedical outcomes like blood pressure, glucose levels or weight. Some studies showed improved management of risk factors like increased control of hypertension or adherence to medication. Conclusion. There have been effective community-based programmes aimed at reducing cardiovascular risk factors in LMIC but these have generally been limited to the urban poor. Health education with a focus on diet and salt, training of health care providers and implementing treatment guidelines form key elements in successful programmes.

Ancestry as a Determinant of Mean Population C-Reactive Protein Values: Implications for Cardiovascular Risk Prediction

Background—Eligibility for rosuvastatin treatment for cardiovascular disease prevention includes a C-reactive protein (CRP) concentration >2 mg/L. Most observational studies of CRP and cardiovascular disease have been in Europeans. We evaluated the influence of ancestry on population CRP concentration to assess the implications for statin targeting in non-Europeans. Methods and Results—In a systematic review and meta-analysis among 221 287 people from 89 studies, geometric mean CRP was 2.6 mg/L (95% credible interval, 2.27 to 2.96) in blacks resident in the United States (n=18 585); 2.51 mg/L (95% CI, 1.18 to 2.86) in Hispanics (n=5049); 2.34 mg/L (95% CI, 1.99 to 2.8) in South Asians (n=1053); 2.03 mg/L (95% CI, 1.77 to 2.3) in whites (n=104 949); and 1.01 mg/L (95% CI, 0.88 to 1.18) in East Asians (n=39 521). Differences were not explained by study design or CRP assay and were preserved after adjustment for age and body mass index. At age 60 years, fewer than half of East Asians but more than two thirds of Hispanics were estimated to have CRP values exceeding 2 mg/L. HapMap frequencies of CRP polymorphisms known to associate with CRP concentration but not coronary heart disease events differed by ancestry. In participant data from the Wandsworth Heart and Stroke Study including European, South Asian and African, and Caribbean-descent subjects, body mass index, systolic blood pressure, and smoking contributed to between-group differences in CRP, but the majority of the difference in CRP was unexplained. Conclusions—Differences in CRP concentration in populations of diverse ancestry are sufficiently large to affect statin eligibility, based on a single CRP threshold of 2 mg/L, and only partially influenced by differences in variables related to cardiovascular risk. A single threshold value of CRP for cardiovascular risk prediction could lead to inequalities in statin eligibility that may not accurately reflect underlying levels of cardiovascular risk.

Hypertensive target organ damage in Ghanaian civil servants with hypertension.

Background Low levels of detection, treatment and control of hypertension have repeatedly been reported from sub Saharan Africa, potentially increasing the likelihood of target organ damage. Methods A cross-sectional study was conducted on 1015 urban civil servants aged≥25 years from seven central government ministries in Accra, Ghana. Participants diagnosed to have hypertension were examined for target organ involvement. Hypertensive target organ damage was defined as the detection of any of the following: left ventricular hypertrophy diagnosed by electrocardiogram, reduction in glomerular filtration rate, the presence of hypertensive retinopathy or a history of a stroke. Results Of the 219 hypertensive participants examined, 104 (47.5%) had evidence of target organ damage. The presence of target organ damage was associated with higher systolic and diastolic blood pressure levels. The odds of developing hypertensive target organ damage was five to six times higher in participants with blood pressure (BP)≥180/110 mmHg compared to those with BP<140/90 mmHg, and there was a trend to higher odds of target organ damage with increasing BP (p = 0.001). Women had about lower odds of developing target organ damage compared to men. Conclusions The high prevalence of target organ damage in this working population associated with increasing blood pressure, emphasises the need for hypertension control programs aimed at improving the detection of hypertension, and importantly addressing the issues inhibiting the effective treatment and control of people with hypertension in the population.

Provision of acute stroke care and associated factors in a multiethnic population: prospective study with the South London Stroke Register

Objectives To investigate time trends in receipt of effective acute stroke care and to determine the factors associated with provision of care. Design Population based stroke register. Setting South London. Participants 3800 patients with first ever ischaemic stroke or primary intracerebral haemorrhage registered between January 1995 and December 2009. Main outcome measures Acute care interventions, admission to hospital, care on a stroke unit, acute drugs, and inequalities in access to care. Results Between 2007 and 2009, 5% (33/620) of patients were still not admitted to a hospital after an acute stroke, particularly those with milder strokes, and 21% (124/584) of patients admitted to hospital were not admitted to a stroke unit. Rates of admission to stroke units and brain imaging, between 1995 and 2009, and for thrombolysis, between 2005 and 2009, increased significantly (P<0.001). Black patients compared with white patients had a significantly increased odds of admission to a stroke unit (odds ratio 1.76, 95% confidence interval 1.35 to 2.29, P<0.001) and of receipt of occupational therapy or physiotherapy (1.90, 1.21 to 2.97, P=0.01), independent of age or stroke severity. Patients with motor or swallowing deficits were also more likely to be admitted to a stroke unit (1.52, 1.12 to 2.06, P=0.001 and 1.32, 1.02 to 1.72, P<0.001, respectively). Length of stay in hospital decreased significantly between 1995 and 2009 (P<0.001). The odds of brain imaging were lowest in patients aged 75 or more years (P=0.004) and those of lower socioeconomic status (P<0.001). The likelihood of those with a functional deficit receiving rehabilitation increased significantly over time (P<0.001). Patients aged 75 or more were more likely to receive occupational therapy or physiotherapy (P=0.002). Conclusion Although the receipt of effective acute stroke care improved between 1995 and 2009, inequalities in its provision were significant, and implementation of evidence based care was not optimal.

Obesity in urban civil servants in Ghana: Association with pre-adult wealth and adult socio-economic status

OBJECTIVE To investigate the distribution of obesity and its association with pre-adult wealth and adult socio-economic factors in urban Ghanaian civil servants. STUDY DESIGN Cross-sectional study of urban civil servants. METHODS A total of 1015 (615 men and 400 women) civil servants aged 25 years and above employed in seven central government ministries and departments in Accra, Ghana were studied (participation rate 82.7%). RESULTS The prevalence of obesity [body mass index (BMI) > or =30.0 kg/m(2)] was 10% in men and 36% in women. Men of higher pre-adult or current socio-economic position generally had higher mean BMI and waist circumference. In women, however, the mean waist circumference was higher in those of lower socio-economic position (lower education, less pre-adult wealth), but mean BMI did not differ significantly between socio-economic groups. There was a positive graded association between pre-adult and adult levels of wealth (determined by the availability of selected household amenities) and the risk of obesity in men (P-trend=0.003), but weak suggestions of an inverse association between adult level of wealth and obesity in women under 45 years of age. CONCLUSIONS The high prevalence of obesity in this population indicates the need for appropriate interventions for its prevention and treatment. Programmes and interventions to control obesity need to address different needs of men and women in the various social strata, and must not be limited to adults.

Rationale and cross-sectional study design of the Research on Obesity and type 2 Diabetes among African Migrants: the RODAM study.

Introduction Obesity and type 2 diabetes (T2D) are highly prevalent among African migrants compared with European descent populations. The underlying reasons still remain a puzzle. Gene–environmental interaction is now seen as a potential plausible factor contributing to the high prevalence of obesity and T2D, but has not yet been investigated. The overall aim of the Research on Obesity and Diabetes among African Migrants (RODAM) project is to understand the reasons for the high prevalence of obesity and T2D among sub-Saharan Africans in diaspora by (1) studying the complex interplay between environment (eg, lifestyle), healthcare, biochemical and (epi)genetic factors, and their relative contributions to the high prevalence of obesity and T2D; (2) to identify specific risk factors within these broad categories to guide intervention programmes and (3) to provide a basic knowledge for improving diagnosis and treatment. Methods and analysis RODAM is a multicentre cross-sectional study among homogenous sub-Saharan African participants (ie, Ghanaians) aged >25 years living in rural and urban Ghana, the Netherlands, Germany and the UK (http://rod-am.eu/). Standardised data on the main outcomes, genetic and non-genetic factors are collected in all locations. The aim is to recruit 6250 individuals comprising five subgroups of 1250 individuals from each site. In Ghana, Kumasi and Obuasi (urban stratum) and villages in the Ashanti region (rural stratum) are served as recruitment sites. In Europe, Ghanaian migrants are selected through the municipality or Ghanaian organisations registers. Ethics and dissemination Ethical approval has been obtained in all sites. This paper gives an overview of the rationale, conceptual framework and methods of the study. The differences across locations will allow us to gain insight into genetic and non-genetic factors contributing to the occurrence of obesity and T2D and will inform targeted intervention and prevention programmes, and provide the basis for improving diagnosis and treatment in these populations and beyond.