Hypertension In Sub-Saharan Africa

Ethnic differences in prevalence and risk factors for hypertension in the Suriname Health Study: a cross sectional population study

BACKGROUND

Limited information is available about the prevalence, ethnic disparities, and risk factors of hypertension within developing countries. We used data from a nationwide study on non-communicable disease (NCD) risk factors to estimate, explore, and compare the prevalence of hypertension overall and in subgroups of risk factors among different ethnic groups in Suriname.

METHOD

The Suriname Health Study used the World Health Organization Steps design to select respondents with a stratified multistage cluster sample of households. The overall and ethnic specific prevalences of hypertension were calculated in general and in subgroups of sex, age, marital status, educational level, income status, employment, smoking status, residence, physical activity, body mass index (BMI), and waist circumference (WC). Differences in the prevalence between ethnic subgroups were assessed using the Chi-square test. We used several adjustment models to explore whether the observed ethnic differences were explained by biological, demographic, lifestyle, or anthropometric risk factors.

RESULTS

The prevalence of hypertension was 26.2 % (95 % confidence interval 25.1 %-27.4 %). Men had higher mean values for systolic and diastolic blood pressure compared to women. Blood pressure increased with age. The prevalence was highest for Creole, Hindustani, and Javanese and lowest for Amerindians, Mixed, and Maroons. Differences between ethnic groups were measured in the prevalence of hypertension in subcategories of sex, marital status, education, income, smoking, physical activity, and BMI. The major difference in association of ethnic groups with hypertension was between Hindustani and Amerindians.

CONCLUSION

The prevalence of hypertension in Suriname was in the range of developing countries. The highest prevalence was found in Creoles, Hindustani, and Javanese. Differences in the prevalence of hypertension were observed between ethnic subgroups with biological, demographic, lifestyle, and anthropometric risk factors. These findings emphasize the need for ethnic-specific research and prevention and intervention programs.

Hypertension and Obesity in Dakar, Senegal

BACKGROUND

Cardiovascular disease is a major public health problem in many sub-Saharan African countries, but data on the main cardiovascular risk factors-hypertension and obesity-are almost nonexistent in Senegal. The aims of this study were therefore (i) to report the prevalence, awareness, treatment and control of hypertension among adults in Dakar, (ii) to assess the prevalence of general and central obesity, and (iii) to analyze the association between hypertension and general and central obesity.

METHODS

A cross-sectional survey was carried out in 2015 on a representative sample of 1000 dwellers of the Senegalese capital aged 20-90.

RESULTS

The overall prevalence of hypertension was 24.7%. Among hypertensive respondents, 28.4% were aware of their condition; 16.0% were on antihypertensive medication; 4.9% had controlled blood pressure. The frequency of doctor visits was a significant predictor of awareness (OR = 2.16; p<0.05) and treatment (OR = 2.57; p<0.05) of hypertension. The prevalence of underweight, overweight and general obesity were 12.6%, 19.2% and 9.7% respectively. The prevalence of central obesity was 26% by WC and 39.8% by WHtR. General obesity and central obesity by WHtR significantly predicted HTN among men and women, but not central obesity by WC.

CONCLUSIONS

This study has demonstrated a high prevalence of hypertension in Dakar and a high prevalence of obesity among women-particularly among older women. The awareness, treatment, and effective control of hypertension are unacceptably low. The blood pressure of women with general obesity, and men with central obesity, in the community should be monitored regularly to limit the burden of cardiovascular disease in Senegal.

Examining risk factors for hypertension in Ghana: evidence from the Study on Global Ageing and Adult Health

Like most countries in sub-Saharan Africa, hypertension contributes substantially to morbidity and mortality in Ghana, yet nationally representative studies that examine the odds of becoming hypertensive among Ghanaians are conspicuously missing. We aimed to fill this void in the literature. The data used for analysis came from the first wave of the Study on Global Ageing and Adult Health (SAGE), collected in Ghana from January 2007 to December 2008 by the World Health Organization (WHO). A total of 5573 respondents were sampled for the study. Random-effects C-log-log models were employed in examining socio-economic, lifestyle and psychosocial factors on the odds of becoming hypertensive in Ghana. Separate models were run for male and females. Results indicated there were strong significant associations between socio-economic, lifestyle and psychosocial factors on the likelihood of becoming hypertensive, among Ghanaian men and women. Compared with the poorest, Ghanaians from wealthy households were significantly more likely to be hypertensive. Educated women, as compared with the uneducated, were also more likely to be hypertensive. Ghanaians who engaged in vigorous or intensive activities continuously, for at least 10 minutes, were significantly less likely to be hypertensive, compared to those who did not. Happier men had lower odds of becoming hypertensive, and depressed women had increased odds of reporting they were hypertensive.

Population-Based Assessment of Hypertension Epidemiology and Risk Factors among HIV-Positive and General Populations in Rural Uganda

BACKGROUND

Antiretroviral therapy scale-up in Sub-Saharan Africa has created a growing, aging HIV-positive population at risk for non-communicable diseases such as hypertension. However, the prevalence and risk factors for hypertension in this population remain incompletely understood.

METHODS

We measured blood pressure and collected demographic data on over 65,000 adults attending multi-disease community health campaigns in 20 rural Ugandan communities (SEARCH Study: NCT01864603). Our objectives were to determine (i) whether HIV is an independent risk factor for hypertension, and (ii) awareness and control of hypertension in HIV-positive adults and the overall population.

RESULTS

Hypertension prevalence was 14% overall, and 11% among HIV-positive individuals. 79% of patients were previously undiagnosed, 85% were not taking medication, and 50% of patients on medication had uncontrolled blood pressure. Multivariate predictors of hypertension included older age, male gender, higher BMI, lack of education, alcohol use, and residence in Eastern Uganda. HIV-negative status was independently associated with higher odds of hypertension (OR 1.2, 95% CI: 1.1-1.4). Viral suppression of HIV did not significantly predict hypertension among HIV-positives.

SIGNIFICANCE

The burden of hypertension is substantial and inadequately controlled, both in HIV-positive persons and overall. Universal HIV screening programs could provide counseling, testing, and treatment for hypertension in Sub-Saharan Africa.

Shining a Light on Task-Shifting Policy: Exploring opportunities for adaptability in non-communicable disease management programmes in Uganda

In terms of disease burden, many low- and middle-income countries are currently experiencing a transition from infectious to chronic diseases. In Uganda, non-communicable diseases (NCDs) have increased significantly in recent years; this challenge is compounded by the healthcare worker shortage and the underfunded health system administration. Addressing the growing prevalence of NCDs requires evidence-based policies and strategies to reduce morbidity and mortality rates; however, the integration and evaluation of new policies and processes pose many challenges. Task-shifting is the process whereby specific tasks are transferred to health workers with less training and fewer qualifications. Successful implementation of a task-shifting policy requires appropriate skill training, clearly defined roles, adequate evaluation, an enhanced training capacity and sufficient health worker incentives. This article focuses on task-shifting policy as a potentially effective strategy to address the growing burden of NCDs on the Ugandan healthcare system.

The feasibility and acceptability of screening for hypertension in private drug retail outlets: a pilot study in Mwanza region, Tanzania

BACKGROUND

Hypertension is a major contributor to ill health in sub-Saharan Africa. Developing countries need to increase access for screening. This study assesses the feasibility and acceptability of using private sector drug retail outlets to screen for hypertension in Mwanza region, Tanzania.

METHODS

A pilot study took place in eight drug retail outlets from August 2013 to February 2014. Customers ≥18 years were invited for screening. Socio-demographic characteristics, hypertension knowledge, hypertension screening and treatment history were collected. Subjects with systolic blood pressure over 140 mmHg were referred for follow up. Referral slips captured attendance. Mystery client visits and follow up phone calls were conducted to assess service quality.

RESULTS

A total of 971 customers were screened, one person refused; 109 (11.2%) had blood pressure over 140/90 mmHg and were referred for ongoing assessment; 85/109 (78.0%) were newly diagnosed. Customers reported that the service was acceptable. Service providers were able to follow the protocol. Only 18/85 (21%) newly diagnosed participants visited the referral clinic within two weeks.

CONCLUSIONS

Blood pressure screening was feasible and acceptable to customers of private drug retail outlets. However many who were referred failed to attend at a referral centre and further research is needed in this area.

Prevalence, awareness, treatment, control and socio demographic determinants of hypertension in Malaysian adults

BACKGROUND

Hypertension is the leading cardiovascular risk factor globally as well as in Malaysia. This study aimed to estimate the prevalence, awareness, treatment, control and the socio demographic determinants of hypertension among Malaysian adults.

METHOD

The analytic sample consisted of 11,288 adults aged ≥ 30 years recruited at baseline in 2007-2011 from the REDISCOVER Study which is an ongoing, prospective cohort study involving 18 urban and 22 rural communities in Malaysia. Socio-demographics, anti-hypertensive treatment details and an average of at least two blood pressure measurements were obtained.

RESULTS

The age-adjusted prevalence was 42.0 % (CI: 40.9-43.2) and was higher in men [43.5 % (CI: 41.2-45.0)] than women [41.0 % (CI: 39.8-42.3)]. Participants from rural areas (APR: 1.12, CI: 1.04-1.20); aged at least 40-49 years (APR: 1.86, CI: 1.62-2.14); who were overweight (APR: 1.24, CI: 1.15-1.34) and obese (APR: 1.54, CI: 1.43-1.6) were more likely to have hypertension. The Indigenous ethnic group was less likely to be aware (APR: 0.81, CI: 0.69-0.92) and to be on treatment (APR: 0.66, CI: 0.55-0.79). Those in rural areas were less likely to have their hypertension controlled (APR: 0.61, CI: 0.49-0.75). On the other hand, control was more likely in females (APR: 1.25, CI: 1.01-1.54) and Indigenous group (APR: 1.64, CI: 1.19-2.25).

CONCLUSION

Hypertension is common in the Malaysian adults. The control of hypertension has increased over the years but is still quite low. Public health measures, as well as individual interventions in primary care are crucial to reduce their risk of developing complications.

Emerging Early Actions to Bend the Curve in Sub-Saharan Africa's Nutrition Transition

BACKGROUND

Sub-Saharan Africa is the last region to undergo a nutrition transition and can still avoid its adverse health outcomes.

OBJECTIVE

The article explores emerging responses to "bend the curve" in sub-Saharan Africa's nutrition transition to steer public health outcomes onto a healthier trajectory.

METHODS

Early responses in 3 countries at different stages of food system transformation are examined: South Africa-advanced, Ghana-intermediate, and Uganda-early. By comparing these with international experience, actions are proposed to influence nutrition and public health trajectories as Africa's food systems undergo rapid structural change.

RESULTS

Arising from rapid urbanization and diet change, major public health problems associated with overweight are taking place, particularly in South Africa and among adult women. However, public health responses are generally tepid in sub-Saharan Africa. Only in South Africa have policy makers instituted extensive actions to combat overweight and associated noncommunicable diseases through regulation, education, and public health programs. Elsewhere, in countries in the early and middle stages of transition, public health systems continue to focus their limited resources primarily on undernutrition. Related pressures on the supply side of Africa's food systems are emerging that also need to be addressed.

CONCLUSIONS

Three types of intervention appear most feasible: maternal and child health programs to simultaneously address short-term undernutrition problems while at the same time helping to reduce future tendencies toward overweigh; regulatory and fiscal actions to limit access to unhealthy foods; and modernization of Africa's agrifood food system through job skills training, marketing reforms, and food industry entrepreneurship.

Local Actors' Frames of the Role of Living Conditions in Shaping Hypertension Risk and Disparities in a Colombian Municipality

Conditions in the social and physical environment influence population health and risk for CVD, including hypertension. These environmental conditions are influenced by the decisions of public officials, community leaders, and service providers. Examining the frames that local decision makers bring to understanding hypertension can provide important insights into the decisions that they make about strategies for addressing this problem in their jurisdiction. The goal of this study was to examine the frames that local decision makers in Quibdó, Colombia, bring to understanding hypertension risk, and in particular, whether and how they use frames that encompass associations between living conditions and hypertension risk. Data for this qualitative study were collected using a stratified sampling strategy. Semi-structured interviews were conducted in 2012 with 13 local decision makers and analyzed using a framework approach. Participants linked the structural conditions experienced in Quibdó, including displacement, limited economic opportunities, and the infrastructure of the city, to hypertension risk through multiple pathways, including behavioral risk factors for hypertension and physiologic responses to stress. They described the social patterning of these factors across socioeconomic, racial/ethnic, and gender hierarchies. Although several conditions associated with hypertension risk are widely distributed in the city's population, social processes of marginalization and stratification create additional disadvantages for those on the lower rungs of the social hierarchy.

Neglected chronic disease: The WHO framework on non-communicable diseases and implications for the global poor

The current global framework on noncommunicable disease (NCD), as exemplified by the WHO Action Plan of 2012, neglects the needs of the global poor. The current framework is rooted in an outdated pseudo-evolutionary theory of epidemiologic transition, which weds NCDs to modernity, and relies on global aggregate data. It is oriented around a simplistic causal model of behaviour, risk and disease, which implicitly locates 'risk' within individuals, conveniently drawing attention away from important global drivers of the NCD epidemic. In fact, the epidemiologic realities of the bottom billion reveal a burden of neglected chronic diseases that are associated with 'alternative' environmental and infectious risks that are largely structurally determined. In addition, the vertical orientation of the framework fails to centralise health systems and delivery issues that are essential to chronic disease prevention and treatment. A new framework oriented around a global health equity perspective would be able to correct some of the failures of the current model by bringing the needs of the global poor to the forefront, and centralising health systems and delivery. In addition, core social science concepts such as Bordieu's habitus may be useful to re-conceptualising strategies that may address both behavioural and structural determinants of health.

Neighborhood clustering of non-communicable diseases: results from a community-based study in Northern Tanzania

Background

In order to begin to address the burden of non-communicable diseases (NCDs) in sub-Saharan Africa, high quality community-based epidemiological studies from the region are urgently needed. Cluster-designed sampling methods may be most efficient, but designing such studies requires assumptions about the clustering of the outcomes of interest. Currently, few studies from Sub-Saharan Africa have been published that describe the clustering of NCDs. Therefore, we report the neighborhood clustering of several NCDs from a community-based study in Northern Tanzania.

Methods

We conducted a cluster-designed cross-sectional household survey between January and June 2014. We used a three-stage cluster probability sampling method to select thirty-seven sampling areas from twenty-nine neighborhood clusters, stratified by urban and rural. Households were then randomly selected from each of the sampling areas, and eligible participants were tested for chronic kidney disease (CKD), glucose impairment including diabetes, hypertension, and obesity as part of the CKD-AFRiKA study. We used linear mixed models to explore clustering across each of the samplings units, and we estimated absolute-agreement intra-cluster correlation (ICC) coefficients (ρ) for the neighborhood clusters.

Results

We enrolled 481 participants from 346 urban and rural households. Neighborhood cluster sizes ranged from 6 to 49 participants (median: 13.0; 25th–75th percentiles: 9–21). Clustering varied across neighborhoods and differed by urban or rural setting. Among NCDs, hypertension (ρ = 0.075) exhibited the strongest clustering within neighborhoods followed by CKD (ρ = 0.440), obesity (ρ = 0.040), and glucose impairment (ρ = 0.039).

Conclusion

The neighborhood clustering was substantial enough to contribute to a design effect for NCD outcomes including hypertension, CKD, obesity, and glucose impairment, and it may also highlight NCD risk factors that vary by setting. These results may help inform the design of future community-based studies or randomized controlled trials examining NCDs in the region particularly those that use cluster-sampling methods.

Determinants of Mean Blood Pressure and Hypertension among Workers in West Africa

Background. This review was undertaken to estimate the mean blood pressure and evaluate its determinants as well as the determinants of hypertension among workers in West Africa. Methods. In a follow-up to an earlier study, a systematic search for articles published between 1980 and August 2015 was undertaken using major databases. Results. A total of 55 articles involving 34,919 different cadres of workers from six countries were retrieved. The mean systolic blood pressure (BP) ranged from 116.6 ± 1.3 mmHg to 151.7 ± 13.6 mmHg while the mean diastolic BP ranged from 69.6 ± 11.0 mmHg to 97.1 ± 9.1 mmHg. Population-wide prehypertension was common. The major determinants of mean BP and hypertension were similar and included male sex, older age group, higher socioeconomic status, obesity, alcohol consumption, plasma glucose, and sodium excretion. Ethnicity and educational level were inconsistently associated with hypertension. Workers at higher risk of cardiovascular event did not perceive themselves as such. Conclusion. The prevailing mean prehypertensive BP, low perception of risk, and clustering of risk factors call for interventions such as healthy diets, improved physical activity, and a favourable work environment. Successful models for improving the cardiovascular health of sedentary informal sector workers in Africa are urgently needed.

Blood pressure (BP) control and perceived family support in patients with essential hypertension seen at a primary care clinic in Western Nigeria

Context:

Nonadherence to therapeutic plans has been reported among hypertensive patients. Researchers have also shown that adherence to therapeutic plans improves if motivation in the form of social support is provided. There is a dearth of local studies that explore the influence of family support on treatment outcomes of hypertensive patients.

Aims:

The aim of the study was to determine the relationship between BP control and perceived family support in patients with essential hypertension seen at a primary care setting in Western Nigeria.

Settings and Design:

This was a cross-sectional hospital-based study.

Subjects and Methods:

Systematic random sampling technique was used in selecting 360 hypertensive respondents between April and July 2013. Data were collected through a pretested interviewer-administered questionnaire and a standardized tool, Perceived Social Support Family Scale, which measured the respondents’ level of perceived family support.

Statistical Analysis Used:

Statistical Package for Social Sciences (SPSS) version 17.0 was used to analyze data.

Results:

The majority of the respondents were middle-aged (61.1%) and female (59.4%). Blood pressure (BP) was controlled in 46.4% of the respondents. Most of the respondents (79.4%) had “strong” perceived family support. Strong perceived family support (odds ratio [OR] 4.778, 95% confidence interval [CI] =2.569–8.887) and female gender (OR 1.838, 95% CI = 1.177–2.869) were independent predictors of controlled BP.

Conclusions:

The proportion of hypertensive patients with optimal BP control is low in this practice setting. The positive association between BP control and perceived family support emphasizes the need for physicians to reflect on the available family support when managing hypertensive patients.

Risk factors of hypertension among adults aged 35-64 years living in an urban slum Nairobi, Kenya

Background

Hypertension is an emerging public health problem in Sub Saharan Africa (SSA) and urbanization is considered to favor its emergence. Given a paucity of information on hypertension and associated risk factors among urban slum dwellers in SSA, we aimed to characterize the distribution of risk factors for hypertension and investigate their association with hypertension in an urban slum in Kenya.

Methods

We conducted a community based cross-sectional survey among adults 35 years and older living in Kibera slum Nairobi, Kenya. Trained interviewers collected data on socio demographic characteristics and self reported health behaviours using modified World Health Organization stepwise surveillance questionnaire for chronic disease risk factors. Anthropometric and blood pressure measurements were performed following standard procedures. Multiple logistic regression was used for analysis and odds ratios with 95 % confidence intervals were calculated to identify risk factors associated with hypertension.

Result

A total of 1528 adults were surveyed with a mean age of 46.7 years. The age-standardized prevalence of hypertension was 29.4 % (95 % CI 27.0–31.7). Among the 418 participants classified as hypertensive, over one third (39.0 %) were unaware they had hypertension. Prevalence of current smoking and alcohol consumption was 8.5 and 13.1 % respectively. Over one quarter 26.2 % participants were classified as overweight (Body Mass Index [BMI] ≥25 to ≤29.9 kg/m²), and 17 % classified as obese (BMI ≥30 kg/m²). Overweight, obesity, current smoking, some level of education, highest wealth index, moderate physical activity, older age and being widowed were each independently associated with hypertension. When fit in a multivariable logistic regression model, being a widow [AOR = 1.7; (95 % CI, 1.1–2.6)], belonging to the highest wealth index [AOR = 1.6; (95 % CI, 1.1–2.5)], obesity [AOR = 1.8; 95 % CI, 1.1–3.1)] and moderate physical activity [AOR = 1.9; (95 % CI, 1.2–3.0)], all remained significantly associated with hypertension.

Conclusion

Hypertension in the slum is a public health problem affecting at least one in three adults aged 35–64 years. Age, marital status, wealth index, physical inactivity and body mass index are important risk factors associated with hypertension. Prevention measures targeting the modifiable risk factors associated with hypertension are warranted to curb hypertension and its progressive effects.

Prevalence of hypertension in Ethiopia: a systematic meta-analysis

BACKGROUND

Hypertension has been increasing in developing countries including Ethiopia. Other than smaller studies, there is no national prevalence study on hypertension in Ethiopia. These smaller studies reported varied prevalence of hypertension. This study is intended to summarize and pool the results of smaller region based studies to provide a national level estimate of the prevalence of hypertension.

METHODS

The studies were identified through internet search using the data base of MEDLINE/PubMed, Google scholar, EMBASE, HINARI, Cochrane library and reference lists of previous prevalence studies. We also made manual searches to identify relevant articles. Descriptive information for the original studies is presented in a table and the quantitative results were presented in forest plots. The Cochrane Q test and I2 test statistic were used to test heterogeneity across studies. The Pooled estimate of prevalence of hypertension was computed by a random effects model.

RESULTS

One hundred eight titles were identified through electronic searching using keywords. Of these, nine studies were meet the inclusion criteria. A random effect meta-analysis of the results from these 9 studies was conducted to provide an estimate of the prevalence of hypertension in the Ethiopian population. The analysis showed that the prevalence of hypertension among Ethiopian population was estimated to be 19.6 % (95 % CI: 13.7 %, 25.5 %). Subgroup analyses indicated that the prevalence of hypertension is higher in the urban population (23.7 %) than rural and urban combined (14.7 %). The prevalence of hypertension among males (20.6 %) and females (19.2 %) was similar.

CONCLUSION

This study found that the prevalence of hypertension in Ethiopia is increasing. This evidence suggests that attention has to be given to primary prevention of hypertension in the Ethiopian adult population, especially in the urban population by integrating it with health extension programs.

The burden of hypertension in sub-Saharan Africa: a four-country cross sectional study

Background

Hypertension, the leading single cause of morbidity and mortality worldwide, is a growing public health problem in sub-Saharan Africa (SSA). Few studies have estimated and compared the burden of hypertension across different SSA populations. We conducted a cross-sectional analysis of blood pressure data collected through a cohort study in four SSA countries, to estimate the prevalence of pre-hypertension, the prevalence of hypertension, and to identify the factors associated with hypertension.

Methods

Participants were from five different population groups defined by occupation and degree of urbanization, including rural and peri-urban residents in Uganda, school teachers in South Africa and Tanzania, and nurses in Nigeria. We used a standardized questionnaire to collect data on demographic and behavioral characteristics, injuries, and history of diagnoses of chronic diseases and mental health. We also made physical measurements (weight, height and blood pressure), as well as biochemical measurements; which followed standardized protocols across the country sites. Modified Poison regression modelling was used to estimate prevalence ratios (PR) as measures of association between potential risk factors and hypertension.

Results

The overall age-standardized prevalence of hypertension among the 1216 participants was 25.9 %. Prevalence was highest among nurses with an age-standardized prevalence (ASP) of 25.8 %, followed by school teachers (ASP = 23.2 %), peri-urban residents (ASP = 20.5 %) and lowest among rural residents (ASP = 8.7 %). Only 50.0 % of participants with hypertension were aware of their raised blood pressure. The overall age-standardized prevalence of pre-hypertension was 21.0 %. Factors found to be associated with hypertension were: population group, older age, higher body mass index, higher fasting plasma glucose level, lower level of education, and tobacco use.

Conclusions

The prevalence of hypertension and pre-hypertension are high, and differ by population group defined by occupation and degree of urbanization. Only half of the populations with hypertension are aware of their hypertension, indicating a high burden of undiagnosed and un-controlled high blood pressure in these populations.

Prevalence of Hypertension in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

We aimed to obtain overall and regional estimates of hypertension prevalence, and to examine the pattern of this disease condition across different socio-demographic characteristics in low-and middle-income countries. We searched electronic databases from inception to August 2015. We included population-based studies that reported hypertension prevalence using the current definition of blood pressure ≥140/90 mm Hg or self-reported use of antihypertensive medication. We used random-effects meta-analyses to pool prevalence estimates of hypertension, overall, by World Bank region and country income group. Meta-regression analyses were performed to explore sources of heterogeneity across the included studies. A total of 242 studies, comprising data on 1,494,609 adults from 45 countries, met our inclusion criteria. The overall prevalence of hypertension was 32.3% (95% confidence interval [CI] 29.4-35.3), with the Latin America and Caribbean region reporting the highest estimates (39.1%, 95% CI 33.1-45.2). Pooled prevalence estimate was also highest across upper middle income countries (37.8%, 95% CI 35.0-40.6) and lowest across low-income countries (23.1%, 95% CI 20.1-26.2). Prevalence estimates were significantly higher in the elderly (≥65 years) compared with younger adults (<65 years) overall and across the geographical regions; however, there was no significant sex-difference in hypertension prevalence (31.9% vs 30.8%, P = 0.6). Persons without formal education (49.0% vs 24.9%, P < 0.00001), overweight/obese (46.4% vs 26.3%, P < 0.00001), and urban settlers (32.7% vs 25.2%, P = 0.0005) were also more likely to be hypertensive, compared with those who were educated, normal weight, and rural settlers respectively. This study provides contemporary and up-to-date estimates that reflect the significant burden of hypertension in low- and middle-income countries, as well as evidence that hypertension remains a major public health issue across the various socio-demographic subgroups. On average, about 1 in 3 adults in the developing world is hypertensive. The findings of this study will be useful for the design of hypertension screening and treatment programmes in low- and middle-income countries.

Results of a hypertension and diabetes treatment program in the slums of Nairobi: a retrospective cohort study

Background

Cardiovascular diseases (CVD) are the world’s leading cause of death and their prevalence is rising. Diabetes and hypertension, major risk factors for CVD, are highly prevalent among the urban poor in Africa, but treatment options are often limited in such settings. This study reports on the results of an intervention for the treatment of diabetes and hypertension for adult residents of two slums in Nairobi, Kenya.

Methods

After setting up two clinics in two slums in Nairobi, hypertension and/or diabetes patients were seen by a clinician monthly. Socio-demographic characteristics and clinical data were collected over a 34-month period. Records were analyzed for 726 patients who visited the clinics at least once to determine clinic attendance and compliance patterns using survival analysis. We also examined changes in systolic blood pressure (SBP), diastolic blood pressure (DBP) and random blood glucose (RBG) during the course of the program.

Results

There was poor compliance with clinic attendance as only 3.4 % of patients attended the clinics on a regular (monthly) basis throughout the 34-month period. 75 % of hypertension patients were not compliant after four visits and 27 % of patients had only one clinic visit. Significant reduction of mean SBP and DBP (150.4 mmHg to 141.5 mmHg, P = .003, and 89.3 mmHg to 83.2 mmHg, P < .001) was seen for all patients that stayed in care for at least one year.

Conclusions

Establishing a preventative care and treatment system in low resource settings for CVD is challenging due to high dropout rates and non-compliance. Innovative strategies are needed to ensure that benefits of treatment programs are sustained for long-term CVD risk reduction in poor urban populations.

Endothelium nitric oxide-independent vasorelaxant effects of the aqueous extract from Stephania abyssinica on the isolated rat thoracic aorta

BACKGROUND

Stephania abyssinica (Dillon & A. Rich) Walp (Menispermaceae) is a medicinal plant used in the west region of Cameroon to treat arterial hypertension. The present study evaluated the vasorelaxant effects of the aqueous (AESA) and methanol (MESA) extracts from the fresh leaves of S. abyssinica on aorta rings isolated from Wistar rats.

METHODS

Aorta rings with intact endothelium were contracted with KCl (60 mM) or phenylephrine (10-5 M) and exposed to cumulative concentrations of each extract, ranging from 10 to 1,000 µg/mL. The vasorelaxant effects of AESA were further evaluated in presence of Nω-nitro-L-arginine methyl ester (L-NAME, 10-4 M), tetraethylammonium (TEA, 5 µM), glibenclamide (5 µM), propranolol (5 µM), and the association glibenclamide-propranolol (AGP). In another set of experiments, the effect of AESA was evaluated on calcium-induced contraction in a hyperpotassic milieu.

RESULTS

AESA and MESA exhibited a concentration-dependent vasorelaxation on KCl-contracted aortic rings with respective EC50 of 160.10 and 346.50 µg/mL. AESA similarly relaxed aortic rings contracted with phenylephrine (EC50, 176.80 µg/mL). The vasorelaxant activity of AESA was not significantly affected by L-NAME but was markedly reduced by TEA, glibenclamide, propranolol, and AGP. AESA strongly inhibited the Ca2+-induced contraction by 95%.

CONCLUSIONS

These results support the use of S. abyssinica against arterial hypertension and suggest that the vasorelaxant effect of AESA is not mediated via the endothelium/nitric oxide pathway. AESA relaxant properties might be due to an inhibition of Ca2+ influx and/or the activation of ATP-sensitive K+ channels probably via the stimulation of β-adrenergic receptors.

Preparedness of Tanzanian health facilities for outpatient primary care of hypertension and diabetes: a cross-sectional survey

Background

Historically, health facilities in sub-Saharan Africa have mainly managed acute, infectious diseases. Few data exist for the preparedness of African health facilities to handle the growing epidemic of chronic, non-communicable diseases (NCDs). We assessed the burden of NCDs in health facilities in northwestern Tanzania and investigated the strengths of the health system and areas for improvement with regard to primary care management of selected NCDs.

Methods

Between November, 2012, and May, 2013, we undertook a cross-sectional survey of a representative sample of 24 public and not-for-profit health facilities in urban and rural Tanzania (four hospitals, eight health centres, and 12 dispensaries). We did structured interviews of facility managers, inspected resources, and administered self-completed questionnaires to 335 health-care workers. We focused on hypertension, diabetes, and HIV (for comparison). Our key study outcomes related to service provision, availability of guidelines and supplies, management and training systems, and preparedness of human resources.

Findings

Of adult outpatient visits to hospitals, 58% were for chronic diseases compared with 20% at health centres, and 13% at dispensaries. In many facilities, guidelines, diagnostic equipment, and first-line drug therapy for the primary care of NCDs were inadequate, and management, training, and reporting systems were weak. Services for HIV accounted for most chronic disease visits and seemed stronger than did services for NCDs. Ten (42%) facilities had guidelines for HIV whereas three (13%) facilities did for NCDs. 261 (78%) health workers showed fair knowledge of HIV, whereas 198 (59%) did for hypertension and 187 (56%) did for diabetes. Generally, health systems were weaker in lower-level facilities. Front-line health-care workers (such as non-medical-doctor clinicians and nurses) did not have knowledge and experience of NCDs. For example, only 74 (49%) of 150 nurses had at least fair knowledge of diabetes care compared with 85 (57%) of 150 for hyptertension and 119 (79%) of 150 for HIV, and only 31 (21%) of 150 had seen more than five patients with diabetes in the past 3 months compared with 50 (33%) of 150 for hypertension and 111 (74%) of 150 for HIV.

Interpretation

Most outpatient services for NCDs in Tanzania are provided at hospitals, despite present policies stating that health centres and dispensaries should provide such services. We identified crucial weaknesses (and strengths) in health systems that should be considered to improve primary care for NCDs in Africa and identified ways that HIV programmes could serve as a model and structural platform for these improvements.

Funding

UK Medical Research Council.

Current Prevalence Pattern of Hypertension in Nigeria: A Systematic Review

BACKGROUND

The global burden of hypertension and other non-communicable diseases (NCDs) is rapidly increasing, and the African continent seems to be the most affected region in the world. The prevalence of hypertension in Nigeria forms a substantial portion of the total burden in Africa because of the large population of the country currently estimated to be over 170 million.

OBJECTIVE

The purpose of this systematic review is to summarise up to date data on the prevalence and distribution of hypertension in Nigeria from prevalence studies.

METHODS

A search of the following databases: PubMed, EMBase and WHO cardiovascular InfoBase from 1968 till date was conducted to identify studies which provide estimates of prevalence of hypertension in Nigeria.

RESULTS

The search yielded a total of 1748 hits from which 45 relevant studies met the inclusion criteria for the review. The overall crude prevalence of hypertension ranged from 0.1% (95%CI:-0.1 to 0.3) to 17.5% (95% CI: 13.6 to 21.4) in children and 2.1% (95%CI: 1.4 to 2.8) to 47.2% (95%CI: 43.6 to 50.8) in adults depending on the benchmark used for diagnosis of hypertension, the setting in which the study was conducted, sex and ethnic group. The crude prevalence of hypertension ranged from 6.2% (95%CI: 4.0 to 8.4) to 48.9% (95%CI: 42.3 to 55.5) for men and 10% (95%CI: 8.1 to 12) to 47.3% (95%CI: 43 to 51.6%) for women. In most studies, prevalence of hypertension was higher in males than females. In addition, prevalence across urban and rural ranged from 9.5% (95%CI: 13.6 to 21.4) to 51.6% (95%CI: 49.8 to 53.4) and 4.8% (95%CI: 2.9 to 6.7) to 43% (95%CI: 42.1 to 43.9) respectively.

CONCLUSIONS

The prevalence of hypertension is high among the Nigerian population. Appropriate interventions need to be developed and implemented to reduce the preventable burden of hypertension especially at Primary Health Care Centres which is the first point of call for over 55% of the Nigerian population.

Application and applicability of non-invasive risk models for predicting undiagnosed prevalent diabetes in Africa: A systematic literature search

BACKGROUND AND PURPOSE

Prediction algorithms are increasingly advocated in diabetes screening strategies, particularly in developing countries. We conducted a systematic review to assess the application and applicability of existing non-invasive prevalent diabetes risk models to populations within Africa.

DESIGN

systematic review data sources A systematic search of English literatures in Medline via PubMed from 1999 until June, 2014. Study selection Included studies had to report on the development, validation or implementation of a model that was primarily constructed to predict prevalent undiagnosed diabetes using non-laboratory based predictors.

DATA EXTRACTION

Data were extracted on the type of statistical model, type and range of predictors in the model, performance measures in both internal and external validation, and whether the model was developed from, validated or implemented in an African population.

RESULTS

Twenty-three studies reporting on non-invasive prevalent diabetes models were identified. Ten from Europe (some with multiethnic populations), nine models were developed among Asian population, two from the USA and two from the Middle-East. The c-statistics for these models ranged from 0.65 to 0.88 in the development studies, and from 0.63 to 0.80 in the validation studies. Twenty models were validated, and none in Africa. Among predictors commonly included in models, parental/family history of diabetes and personal history of hypertension appear to be more prone to measurement errors in the African context.

CONCLUSION

Existing prevalent diabetes prediction models have not been applied to African populations, and issues with the measurement of key predictors make their applicability likely inaccurate.

Prevalence of hypertension and its treatment among adults presenting to primary health clinics in rural Zambia: analysis of an observational database

Background

Hypertension constitutes a growing burden of illness in developing countries like Zambia. Adequately screening and treating hypertension could greatly reduce the complications of stroke and coronary disease. Our objective was to determine the prevalence of hypertension and identify current treatment practices among adult patients presenting for routine care to rural health facilities in the Better Health Outcomes through Mentoring and Assessments (BHOMA) project.

Methods

We conducted a retrospective analysis of routinely collected clinical data from 46 rural government clinics in Zambia. Our analysis cohort comprised patients ≥ 25 years with recorded blood pressure measurements, who sought care at primary health centers. Consistent with prior research, in our primary analysis, we only included data from first visits. Hypertension was defined as a systolic blood pressure ≥140 mmHg, or diastolic blood pressure ≥90 mmHg, or reported use of antihypertensive medication. A sensitivity analysis was performed using median blood pressure for individuals with multiple visits.

Results and Discussion

From January 2011 to December 2014, 116,130 first visits by adult patients met eligibility criteria. The crude prevalence of hypertension by onsite measurement or reported use of antihypertensive medication was 23.1 % [95 % CI: 22.8-23.3] (23.6 % in females, 22.3 % in males). The age standardized prevalence of hypertension across participating sites was 28.0 % [95 % CI: 27.7-28.3] (29.7 % in females, 25.8 % in males). Sensitivity analysis revealed a similar prevalence using data from all visits. Only 5.6 % of patients had a diagnosis of hypertension documented in their medical record. Among patients with hypertension, only 18.0 % had any antihypertensive drug prescribed, with nifedipine (8.9 %), furosemide (8.3 %), and propranolol (2.4 %) as the most common.

Conclusions

Age standardized prevalence of hypertension in rural primary health clinics in Zambia was high compared to other studies in rural Africa; however, we diagnosed hypertension with only one measurement and this may have biased our findings. Future efforts to improve hypertension control should focus on population preventive care and primary healthcare provider education on individual management.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2258-4) contains supplementary material, which is available to authorized users.

Hypertension, a Neglected Disease in Rural and Urban Areas in Moramanga, Madagascar

BACKGROUND

Hypertension is one of the main risk factors of cardiovascular diseases. In Madagascar, studies on hypertension in urban and rural communities are scarce.

OBJECTIVES

The aim of this study was to determine the prevalence of hypertension and identify associated risk factors in adults living in a health and demographic system in Moramanga, Madagascar.

METHODS

The study included people aged 15 years old and above living in a health and demographic system in Moramanga. A household census was performed in 2012 to enumerate the population in 3 communities in Moramanga. In addition to the questionnaire used in the initial census, a standardized questionnaire and blood pressure were taken twice after 5 and 10 minutes of rest. In urban areas, heights and weights were also measured to calculate the body mass index.

RESULTS

There were 3621 and 4010 participants respectively in rural and urban areas. Prevalence of hypertension in rural population was 27.0% (IC95% [25.6-28.5]) and 29.7% (IC95% [28.3-31.1]) in urban population. Among hypertensive subjects, 1.7% (17/979) and 5.3% (64/1191) were on antihypertensive treatment for at least 1 month before the survey in rural and urban population, respectively. In rural areas, increasing age (65 years and older vs 18-25 years OR = 11.81, IC95% [7.79-18.07]), giving more than 3 positive responses to the usual risks factors of hypertension (OR = 1.67, IC95% [1.14-2.42]) and singles in comparison with married people (OR = 1.61, IC95% [1.20-2.17]) were associated to hypertension in a logistic regression model. In urban areas, increasing age (65 years and older vs 18-25 years OR = 37.54, IC95% [24.81-57.92]), more than 3 positive responses to the usual risks of hypertension (OR = 3.47, IC95% [2.58-4.67]) and obesity (OR = 2.45, IC95% [1.56-3.87]) were found as risk factors.

CONCLUSION

Hypertension is highly prevalent in rural areas although it is significantly less treated. As a result, a major epidemic of cardiovascular diseases is at risk in Madagascar's progressively aging society.

Hypertension Prevalence, Awareness and Control Levels among Ghawarna: An African-Descendant Ethnic Minority in the Jordan Valley

OBJECTIVE

Treatment and control of hypertension (HTN) is a challenging issue as undiagnosed HTN prevalence seems to be high among certain ethnic groups, such as African-descendant populations. The current study attempted to measure HTN prevalence, awareness and control levels among Ghawarna, an African-descendant ethnic group living in the Jordan Valley (Al-Ghawr).

DESIGN SETTING AND PARTICIPANTS

A cross-sectional study was conducted in a community of Ghawarna between March and June 2013 in Ghawr Al-Mazraa Village in the southern part of the Jordan Valley. A total of 517 participants, aged >25 years, were randomly selected using cluster random sampling technique.

MAIN MEASURES

Data were collected using an interviewer-administrated questionnaire and on-location measurement of blood pressure (BP), height, and weight. Prevalence rates were compared by sex and age groups using chi-square test while backward selection logistic regression analysis was used to identify predictors of HTN.

RESULTS

We found 229 (44.3%) of the 517 participants had HTN. Of those 229 hypertensives, 146 (28.2%) participants were discovered to have HTN for the "first time." Only 23 of the 83 who were aware of their hypertension had their BP controlled. When we added the undiagnosed HTN (n=146) to the uncontrolled HTN (n=60), the prevalence of uncontrolled HTN became 90% (206/229). Older age, higher BMI, diabetes mellitus, and dyslipidemia were associated with having HTN.

CONCLUSIONS

HTN prevalence, awareness and control levels are alarming among Ghawarna.

Prevalence of hypertension among federal ministry civil servants in Addis Ababa, Ethiopia: a call for a workplace-screening program

BACKGROUND

The prevalence of hypertension (HTN) is increasing rapidly in Ethiopia, but data are limited on hypertension prevalence in specific workplaces. Therefore, the aim of this study was to assess the prevalence and associated factors of hypertension among federal ministry civil servants.

METHODS

Institutional based cross sectional study was conducted from February to April 2014. Simple random sampling technique was used to select 655study participants. A standardized questionnaire adapted from The World Health Organization's (WHO) STEP tool was used to collect the data. In this study, HTN was defined as mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) of 140/90 mmHg and above, and patients on regular drug therapy for H. Data were entered into EPI-Info 3.5.2 and analyzed by SPSS version 20. Binary logistic regression model was used to identify associated factors. Odds ratio with 95 % CI was computed to assess the strength of the association and significant level.

RESULT

The prevalence of hypertension was found to be 27.3 % (95 % CI 23.3 - 31 %). Civil servants of age 48 years and above [AOR = 5.88, 95 % CI: 2.36-14.67], age 38-47 years [AOR = 2.80, 95 % CI: 1.18-6.60] and age 28-37 years [AOR = 2.35, 95 % CI: 1.00-5.56]) were more likely to be hypertensive. Similarly, ever cigarette smoking [AOR =2.34(1.31-4.17), family history of hypertension [AOR = 3.26, 95 % CI 1.96-5.40], self-reported Diabetes Mellitus (DM) [AOR = 13.56, 95 % CI: 6.91-26.6], and body mass index (BMI > 25 kg/m(2)) [AOR = 7.36, 95 % CI: 2.36-14.67] were found to be significantly associated with hypertension.

CONCLUSION

The prevalence of hypertension among federal ministry civil servants was found to be high; which is an indication for institution based hypertension-screening programs especially focusing on those aged 28 years and above, obese, DM patients and cigarette smokers.

Vitamin A: potential misclassification of vitamin A status among patients with type 2 diabetes and hypertension in urban Ghana

BACKGROUND

Sub-Saharan Africa is facing a double burden of malnutrition: vitamin A deficiency (VAD) prevails, whereas the nutrition-related chronic conditions type 2 diabetes (T2D) and hypertension are emerging. Serum retinol—a VAD marker—increases in kidney disease and decreases in inflammation, which can partly be attributed to alterations in the vitamin A-transport proteins retinol-binding protein 4 (RBP4) and prealbumin. Kidney dysfunction and inflammation commonly accompany T2D and hypertension.

OBJECTIVE

Among urban Ghanaians, we investigated the associations of T2D and hypertension with serum retinol as well as the importance of kidney function and inflammation in this regard.

DESIGN

A hospital-based, case-control study in individuals for risk factors of T2D, hypertension, or both was conducted in Kumasi, Ghana (328 controls, 197 with T2D, 354 with hypertension, and 340 with T2D plus hypertension). In 1219 blood samples, serum retinol, RBP4, and prealbumin were measured. Urinary albumin and estimated glomerular filtration rate (eGFR) defined kidney function. C-reactive protein (CRP) >5 mg/L indicated inflammation. We identified associations of T2D and hypertension with retinol by linear regression and calculated the contribution of RBP4, prealbumin, urinary albumin, eGFR, and CRP to these associations as the percentages of the explained variance of retinol.

RESULTS

VAD (retinol <1.05 μmol/L) was present in 10% of this predominantly female, middle-aged, overweight, and deprived population. Hypertension, but not T2D, was positively associated with retinol (β: 0.12; 95% CI: 0.08, 0.17), adjusted for age, sex, socioeconomic factors, anthropometric measurements, and lifestyle. In addition to RBP4 (72%) and prealbumin (22%), the effect of increased retinol on individuals with hypertension was mainly attributed to impaired kidney function (eGFR: 30%; urinary albumin: 5%) but not to inflammation.

CONCLUSIONS

In patients with hypertension, VAD might be underestimated because of increased serum retinol in the context of kidney dysfunction. Thus, the interpretation of serum retinol in sub-Saharan Africa should account for hypertension status.

High prevalence of hypertension and of risk factors for non-communicable diseases (NCDs): a population based cross-sectional survey of NCDS and HIV infection in Northwestern Tanzania and Southern Uganda

BACKGROUND

The burden of non-communicable diseases (NCDs) is increasing in sub-Saharan Africa, but data available for intervention planning are inadequate. We determined the prevalence of selected NCDs and HIV infection, and NCD risk factors in northwestern Tanzania and southern Uganda.

METHODS

A population-based cross-sectional survey was conducted, enrolling households using multistage sampling with five strata per country (one municipality, two towns, two rural areas). Consenting adults (≥18 years) were interviewed using the WHO STEPS survey instrument, examined, and tested for HIV and diabetes mellitus (DM). Adjusting for survey design, we estimated population prevalences of hypertension, DM, obstructive pulmonary disease, cardiac failure, epilepsy and HIV, and investigated factors associated with hypertension using logistic regression.

RESULTS

Across strata, hypertension prevalence ranged from 16 % (95 % confidence interval (CI): 12 % to 22 %) to 17 % (CI: 14 % to 22 %) in Tanzania, and from 19 % (CI: 14 % to 26 %) to 26 % (CI: 23 % to 30 %) in Uganda. It was high in both urban and rural areas, affecting many young participants. The prevalence of DM (1 % to 4 %) and other NCDs was generally low. HIV prevalence ranged from 6 % to 10 % in Tanzania, and 6 % to 12 % in Uganda. Current smoking was reported by 12 % to 23 % of men in different strata, and 1 % to 3 % of women. Problem drinking (defined by Alcohol Use Disorder Identification Test criteria) affected 6 % to 15 % men and 1 % to 6 % women. Up to 46 % of participants were overweight, affecting women more than men and urban more than rural areas. Most patients with hypertension and other NCDs were unaware of their condition, and hypertension in treated patients was mostly uncontrolled. Hypertension was associated with older age, male sex, being divorced/widowed, lower education, higher BMI and, inversely, with smoking.

CONCLUSIONS

The high prevalence of NCD risk factors and unrecognized and untreated hypertension represent major problems. The low prevalence of DM and other preventable NCDs provides an opportunity for prevention. HIV prevalence was in line with national data. In Tanzania, Uganda and probably elsewhere in Africa, major efforts are needed to strengthen health services for the PREVENTION, early detection and treatment of chronic diseases.

Feasibility of a large cohort study in sub-Saharan Africa assessed through a four-country study

BACKGROUND

Large prospective epidemiologic studies are vital in determining disease etiology and forming national health policy. Yet, such studies do not exist in sub-Saharan Africa (SSA) notwithstanding the growing burden of chronic diseases.

OBJECTIVE

We explored the feasibility of establishing a large-scale multicountry prospective study at five sites in four sub-Saharan countries.

DESIGN

Based on country-specific considerations of feasibility, Nigeria enrolled health care professionals, South Africa and Tanzania enrolled teachers, and Uganda enrolled village residents at one rural and one periurban site each. All sites used a 6-month follow-up period but different approaches for data collection, namely standardized questionnaires filled out by participants or face-to-face interviews.

RESULTS

We enrolled 1415 participants from five sites (range 200-489) with a median age of 41 years. Approximately half had access to clean-burning cooking fuel and 70% to piped drinking water, yet 92% had access to a mobile phone. The prevalence of chronic diseases was 49% among 45- to 54-year-olds and was dominated by hypertension (21.7% overall) - ranging from 4.5 to 31.2% across sites - and a serious injury in the past 12 months (12.4% overall). About 80% of participants indicated willingness to provide blood samples. At 6-month follow-up, 68% completed a questionnaire (45 to 96% across sites) with evidence that mobile phones were particularly useful.

CONCLUSIONS

Our pilot study indicates that a large-scale prospective study in SSA is feasible, and the burden of chronic disease in SSA may already be substantial necessitating urgent etiologic research and primary prevention.

Examining the Risk Factors Associated With Hypertension Among the Elderly in Ghana

OBJECTIVE

This study sought to examine the risk factors associated with hypertension among the elderly in Ghana. We focused on the association between chronic diseases, socioeconomic factors, and being hypertensive.

METHOD

Data for the study were drawn from Wave 1 of the 2007/2008 Ghana Study on Global Ageing and Adult Health (SAGE). A binary logit model was used to estimate the effect of other noncommunicable diseases, psychosocial factors, lifestyle factors, and sociocultural and biosocial factors on the elderly being hypertensive.

RESULTS

Elderly Ghanaians who had been diagnosed with arthritis, angina, diabetes, and asthma were significantly more likely to be hypertensive. Additionally, those depressed were found to be 1.22 times more likely to be hypertensive.

DISCUSSION

Prevention and control of hypertension are complex and demand multistakeholder collaboration including governments, educational institutions, media, food and beverage industry, and a conscious focus on personal lifestyle factors.

Cardiovascular prevention model from Kenyan slums to migrants in the Netherlands

Cardiovascular diseases (CVD) are the main cause of morbidity and mortality worldwide. As prevention and treatment of CVD often requires active screening and lifelong follow up it is a challenge for health systems both in high-income and low and middle-income countries to deliver adequate care to those in need, with efficient use of resources.

We developed a health service model for primary prevention of CVD suitable for implementation in the Nairobi slums, based on best practices from public health and the private sectors. The model consists of four key intervention elements focusing on increasing awareness, incentives for promoting access to screening and treatment, and improvement of long-term adherence to prescribed medications. More than 5,000 slum dwellers aged ≥35 years and above have been screened in the study resulting in more than 1000 diagnosed with hypertension and referred to the clinic.

Some marginalized groups in high-income countries like African migrants in the Netherlands also have low rates of awareness, treatment and control of hypertension as the slum population in Nairobi. The parallel between both groups is that they have a combination of risky lifestyle, are prone to chronic diseases such as hypertension, have limited knowledge about hypertension and its complications, and a tendency to stay away from clinics partly due to cultural beliefs in alternative forms of treatment, and lack of trust in health providers. Based on these similarities it was suggested by several policymakers that the model from Nairobi can be applied to other vulnerable populations such as African migrants in high-income countries. The model can be contextualized to the local situation by adapting the key steps of the model to the local settings.

The involvement and support of African communities’ infrastructures and health care staff is crucial, and the most important enabler for successful implementation of the model in migrant communities in high-income countries. Once these stakeholders have expressed their interest, the impact of the adapted intervention can be measured through an implementation research approach including collection of costs from health care providers’ perspective and health effects in the target population, similar to the study design for Nairobi.

Hypertension, cardiovascular risk factors and antihypertensive medication utilisation among HIV-infected individuals in Rakai, Uganda

OBJECTIVES

To assess the prevalence of hypertension, elevated blood pressure and cardiovascular risk factors among HIV-positive individuals in rural Rakai District, Uganda.

METHODS

We assessed 426 HIV-positive individuals in Rakai, Uganda from 2007 to 2010. Prevalence of hypertension and elevated blood pressure assessed by clinical measurement was compared to clinician-recorded hypertension in case report forms. Multiple logistic regression and z-tests were used to examine the association of hypertension and elevated blood pressure with age, sex, body mass index (BMI), CD4 cell count and antiretroviral treatment (ART) use. For individuals on antihypertensives, medication utilisation was reviewed.

RESULTS

The prevalence of hypertension (two elevated blood pressure readings at different time points) was 8.0% (95% CI: 5.4-10.6%), and that of elevated blood pressure (one elevated blood pressure reading) was 26.3% (95% CI: 22.1-30.5%). Age ≥50 years and higher BMI were positively associated with elevated blood pressure. ART use, time on ART and CD4 cell count were not associated with hypertension. Eighty-three percent of subjects diagnosed with hypertension were on antihypertensive medications, most commonly beta-blockers and calcium channel blockers.

CONCLUSIONS

Hypertension is common among HIV-positive individuals in rural Uganda.

Hypertension in Zimbabwe: A meta-analysis to quantify its burden and policy implications

AIM: To estimate the pooled prevalence of hypertension in Zimbabwe and describe its trend since independence in 1980 using secondary source data.

METHODS: MEDLINE, EMBASE and Scopus databases from April 1980 to December 2013 were searched for population and community based studies on the prevalence of hypertension among adults (≥ 18 years) in Zimbabwe. The key words used were “prevalence”, “epidemiologic studies”, “hypertension” or “high blood pressure”, based on the cut-off (≥ 140 mmHg systolic blood pressure and/or ≥ 90 mmHg diastolic blood pressure). We conducted a meta-analysis on the published studies, using the random-effects model to estimate the pooled prevalence.

RESULTS: The search retrieved 87 publications, of which four studies met the selection criteria. The four studies had a total of 4829 study participants between 1997 and 2010 across 5 provinces in Zimbabwe. Two studies were in urban areas, while the other two had mixed study settings (urban and rural). The overall pooled prevalence of hypertension was 30% (95%CI: 19%, 42%, I²= 98%, χ² = 164.15, P = 0.00).

CONCLUSION: Our results show a high prevalence of hypertension in Zimbabwe, with urban areas having higher prevalence than rural areas.

Prevalence, awareness, treatment and control of hypertension in urban poor communities in Accra, Ghana

BACKGROUND

Hypertension is a major public health problem in many sub-Saharan African countries including Ghana, but data on urban poor communities are limited. The aim of this study was therefore to assess the prevalence, awareness, management and control of hypertension among a young adult population in their reproductive ages living in urban poor communities in Accra.

METHODS

Cross-sectional, population-based survey of 714 young adults in their reproductive ages (women aged 15-49 years, men aged 15-59 years) living in three urban poor suburbs of Accra, Ghana.

RESULTS

The overall prevalence of hypertension in all three communities was 28.3% (women 25.6% and men 31.0%). Among respondents who had hypertension, 7.4% were aware of their condition; 4% were on antihypertensive medication while only 3.5% of hypertensive individuals had adequate blood pressure (BP) control (BP <140/90  mmHg). The level of awareness and treatment was lower in men than in women (3.1 and 1.3% for men and 11.9 and 6.5% for women, respectively). Among individuals with hypertension, the rate of control was higher among women than among men (5.0 and 2.1%, respectively).

CONCLUSION

Although about a quarter of the young adult population in these low-income communities of Accra have hypertension, the levels of awareness, treatment and control are abysmally low. We recommend community-specific primary and secondary prevention interventions that draw on existing resources, specifically implementing cardiovascular disease (CVD) interventions in faith-based organizations and task-shifting CVD care through the national Community-based Health Planning and Services (CHPS) programme.

Burden of Undiagnosed Hypertension in Sub-Saharan Africa

The burden of hypertension in Sub-Saharan Africa has been increasing over the past few decades. However, a large proportion of the population with hypertension remains undiagnosed, untreated, or inadequately treated, contributing to the rising burden of cardiovascular disease in the region. We conducted a systematic review and meta-analysis to assess the recent burden of hypertension in Sub-Saharan Africa, based on studies published between 2000 and 2013. We pooled data from 33 surveys involving over 110 414 participants of mean age 40 years. Hypertension prevalence varied widely across the studies (range 15%–70%), partly because of differences in participant mean ages (31–76 years). The predicted prevalence of hypertension at mean participant ages of 30, 40, 50, and 60 years were 16%, 26%, 35%, and 44%, respectively, with a pooled prevalence of 30% (95% confidence interval, 27%–34%). Of those with hypertension, only between 7% and 56% (pooled prevalence: 27%; 95% confidence interval, 23%–31%) were aware of their hypertensive status before the surveys. Overall, 18% (95% confidence interval, 14%–22%) of individuals with hypertension were receiving treatment across the studies, and only 7% (95% confidence interval, 5%–8%) had controlled blood pressure. This review found a high prevalence of hypertension, as well as low percentage of hypertension awareness, treatment, and control in Sub-Saharan Africa, highlighting the need for implementation of timely and appropriate strategies for diagnosis, control, and prevention.

The prevalence, awareness, and control of hypertension among workers in West Africa: a systematic review

BACKGROUND

: Interventions in workplace settings are considered to be cost-effective in preventing cardiovascular diseases. A systematic review was conducted to assess the prevalence of hypertension and the level of awareness and control among workers in West Africa.

DESIGN

A systematic search for studies on formal and informal sector workers aged ≥15 years in West Africa published between 1980 and September 2014 was undertaken using the Ovid Medline, Embase, PubMed, and Google Scholar databases. Clinical and obstetric studies and studies that did not report prevalence were excluded. Data on study settings, characteristics of workers, blood pressure (BP) levels, prevalence of hypertension, and associated demographic factors were extracted.

RESULTS

A total of 45 studies from six countries were identified involving 30,727 formal and informal sector workers. In 40 studies with a common definition of hypertension, the prevalence ranged from 12.0% among automobile garage workers to 68.9% among traditional chiefs. In 15 of these studies, the prevalence exceeded 30%. Typically sedentary workers such as traders, bank workers, civil servants, and chiefs were at high risk. Among health care workers, the prevalence ranged from 17.5 to 37.5%. The prevalence increased with age and was higher among males and workers with higher socio-economic status. Complications of hypertension, co-morbidities, and clustering of risk factors were common. The crude prevalence of hypertension increased progressively from 12.9% in studies published in the 1980s to 34.4% in those published in 2010-2014. The proportion of hypertensives who were previously aware of their diagnosis, were on treatment or had their BP controlled was 19.6-84.0%, 0-79.2%, and 0-12.7%, respectively. Hypertensive subjects, including health workers, rarely checked their BP except when they were ill.

CONCLUSIONS

There is a high prevalence of hypertension among West Africa's workforce, of which a significant proportion is undiagnosed, severe or complicated. The clustering of risk factors, co-morbidities, and general low awareness warrant an integrated and multisectoral approach. Models for workplace health programmes aiming to improve cardiovascular health should be extended to informal sector workers.

Traditional herbal medicine use among hypertensive patients in sub-Saharan Africa: a systematic review

Hypertension is increasingly common in sub-Saharan Africa, and rates of hypertension control are low. Use of traditional herbal medicines (THM) is common among adults in sub-Saharan Africa and may affect hypertension therapy. We searched Ovid MEDLINE, Ovid EMBASE, and Web of Knowledge in June 2013 to find studies about THM use among hypertensive patients living in sub-Saharan Africa. Two independent reviewers evaluated titles and abstracts. Qualifying references were reviewed in full text. Data were extracted using a standardized questionnaire. Four hundred and eighty-one references were retrieved, and four articles from two countries met criteria for inclusion. The prevalence of THM use was 25-65% (average 38.6%). THM was the most common type of complementary and alternative medicines used by patients (86.7-96.6%). Among THM users, 47.5% concomitantly used both allopathic medicine and THM. Increased age (p<0.001), male sex (RR 2.58), belief in a supernatural cause of hypertension (RR 2.11), and family history of hypertension (OR 1.78) were positively associated with THM use, while belief that hypertension is preventable was negatively associated with THM use (OR 0.57). More than one-third of adults with hypertension in sub-Saharan Africa use THM. Half of these patients use THM concurrently with allopathic medicine. Healthcare workers in sub-Saharan Africa must discuss THM use with their hypertensive patients. More research is urgently needed to define the impact of THM use on hypertension control and outcomes in sub-Saharan Africa.

Perceptions of inhibitors and facilitators for adhering to hypertension treatment among insured patients in rural Nigeria: a qualitative study

BACKGROUND

Universal health care coverage has been identified as a promising strategy for improving hypertension treatment and control rates in sub Saharan Africa (SSA). Yet, even when quality care is accessible, poor adherence can compromise treatment outcomes. To provide information for adherence support interventions, this study explored what low income patients who received hypertension care in the context of a community based health insurance program in Nigeria perceive as inhibitors and facilitators for adhering to pharmacotherapy and healthy behaviors.

METHODS

We conducted a qualitative interview study with 40 insured hypertensive patients who had received hypertension care for > 1 year in a rural primary care hospital in Kwara state, Nigeria. Supported by MAXQDA software, interview transcripts were inductively coded. Codes were then grouped into concepts and thematic categories, leading to matrices for inhibitors and facilitators of treatment adherence.

RESULTS

Important patient-identified facilitators of medication adherence included: affordability of care (through health insurance); trust in orthodox "western" medicines; trust in Doctor; dreaded dangers of hypertension; and use of prayer to support efficacy of pills. Inhibitors of medication adherence included: inconvenient clinic operating hours; long waiting times; under-dispensing of prescriptions; side-effects of pills; faith motivated changes of medication regimen; herbal supplementation/substitution of pills; and ignorance that regular use is needed. Local practices and norms were identified as important inhibitors to the uptake of healthier behaviors (e.g. use of salt for food preservation; negative cultural images associated with decreased body size and physical activity). Important factors facilitating such behaviors were the awareness that salt substitutes and products for composing healthier meals were cheaply available at local markets and that exercise could be integrated in people's daily activities (e.g. farming, yam pounding, and household chores).

CONCLUSIONS

With a better understanding of patient perceived inhibitors and facilitators of adherence to hypertension treatment, this study provides information for patient education and health system level interventions that can be designed to improve compliance.

TRIAL REGISTRATION

ISRCTN47894401 .

Non-Communicable Disease Mortality and Risk Factors in Formal and Informal Neighborhoods, Ouagadougou, Burkina Faso: Evidence from a Health and Demographic Surveillance System

The expected growth in NCDs in cities is one of the most important health challenges of the coming decades in Sub-Saharan countries. This paper aims to fill the gap in our understanding of socio-economic differentials in NCD mortality and risk in low and middle income neighborhoods in urban Africa. We use data collected in the Ouagadougou Health and Demographic Surveillance System. 409 deaths were recorded between 2009–2011 among 20,836 individuals aged 35 years and older; verbal autopsies and the InterVA program were used to determine the probable cause of death. A random survey asked in 2011 1,039 adults aged 35 and over about tobacco use, heavy alcohol consumption, lack of physical activity and measured their weight, height, and blood pressure. These data reveal a high level of premature mortality due to NCDs in all neighborhoods: NCD mortality increases substantially by age 50. NCD mortality is greater in formal neighborhoods, while adult communicable disease mortality remains high, especially in informal neighborhoods. There is a high prevalence of risk factors for NCDs in the studied neighborhoods, with over one-fourth of the adults being overweight and over one-fourth having hypertension. Better-off residents are more prone to physical inactivity and excessive weight, while vulnerable populations such as widows/divorced individuals and migrants suffer more from higher blood pressure. Females have a significantly lower risk of being smokers or heavy drinkers, while they are more likely to be physically inactive or overweight, especially when married. Muslim individuals are less likely to be smokers or heavy drinkers, but have a higher blood pressure. Everything else being constant, individuals living in formal neighborhoods are more often overweight. The data presented make clear the pressing need to develop effective programs to reduce NCD risk across all types of neighborhoods in African cities, and suggest several entry points for community-based prevention programs.

Hypertension education intervention with ugandan nurses working in hospital outpatient clinic: a pilot study

Noncommunicable diseases (NCDs) pose a significant global burden in both developed and developing countries. It is estimated that, by 2025, 41.7% of males and 38.7% of females in Sub-Saharan Africa will develop high blood pressure (HBP). This is particularly true in Uganda with hypertensive prevalence rates estimated to range from 22.5% to 30.5%. Coupled with low levels of detection, treatment, and control, hypertension represents a Ugandan public health crisis. An innovative WHO-ISH education program culturally was adapted in a pilot study and focused on knowledge, skills, and attitudes (KSA) of nurses caring for hypertensive patients in an outpatient clinic. Pre-post intervention data was collected and analyzed in which significant improvements were noted on all the three outcome measures. This pilot study demonstrated that nurses' knowledge, skills, and attitudes could be significantly improved with a multimodal education program implemented in a low resource environment.

Association between body fat composition and blood pressure level among secondary school adolescents in Dar es Salaam, Tanzania

INTRODUCTION

Excess body fat and high blood pressure (BP) are important risk factors for increased cardiovascular morbidity and mortality, and both may have their roots of occurrence in childhood and adolescence. The present study aimed at determining the association between body fat composition and BP level among adolescents in Tanzania.

METHODS

A cross-sectional study involving 5 randomly selected secondary schools within Dar es Salaam was conducted between June and November 2013. Structured questionnaires were used to collect information on demographic characteristics and other cardiovascular risk factors. BP, height, weight and waist circumference were measured following standard methods. Body fat was assessed by skinfold thickness and categorized as underfat, healthy, overfat or obese according to World Health Organization definitions. Hypertension was defined as BP ≥ 90(th) percentile for age, height and gender of the adolescent.

RESULTS

The study included 582 adolescents (mean age 16.5 ± 1.8 years, 52.1% boys). The proportion of adolescents with overfat or obesity was 22.2%. Systolic, diastolic and combined hypertension was present in 17.5%, 5.5%, and 4.0% respectively. In the total population mean body fat percent correlated positively with diastolic BP and mean arterial pressure (MAP) but not with systolic BP. In multivariate analysis body mass index (β=0.21, p=0.008) and waist circumference (β=0.12, p=0.049), but not body fat percentage (β=-0.09, p=0.399) independently predicted higher MAP.

CONCLUSION

Body mass index predicts BP level better than body fat composition and should be used as a measure of increased risk for hypertension among adolescents.

Deaths ascribed to non-communicable diseases among rural Kenyan adults are proportionately increasing: evidence from a health and demographic surveillance system, 2003-2010

BACKGROUND

Non-communicable diseases (NCDs) result in more deaths globally than other causes. Monitoring systems require strengthening to attribute the NCD burden and deaths in low and middle-income countries (LMICs). Data from health and demographic surveillance systems (HDSS) can contribute towards this goal.

METHODS AND FINDINGS

Between 2003 and 2010, 15,228 deaths in adults aged 15 years (y) and older were identified retrospectively using the HDSS census and verbal autopsy in rural western Kenya, attributed into broad categories using InterVA-4 computer algorithms; 37% were ascribed to NCDs, 60% to communicable diseases (CDs), 3% to injuries, and <1% maternal causes. Median age at death for NCDs was 66y and 71y for females and males, respectively, with 43% (39% male, 48% female) of NCD deaths occurring prematurely among adults aged below 65y. NCD deaths were mainly attributed to cancers (35%) and cardio-vascular diseases (CVDs; 29%). The proportionate mortality from NCDs rose from 35% in 2003 to 45% in 2010 (χ2 linear trend 93.4; p<0.001). While overall annual mortality rates (MRs) for NCDs fell, cancer-specific MRs rose from 200 to 262 per 100,000 population, mainly due to increasing deaths in adults aged 65y and older, and to respiratory neoplasms in all age groups. The substantial fall in CD MRs resulted in similar MRs for CDs and NCDs among all adult females by 2010. NCD MRs for adults aged 15y to <65y fell from 409 to 183 per 100,000 among females and from 517 to 283 per 100,000 population among males. NCD MRs were higher among males than females aged both below, and at or above, 65y.

CONCLUSIONS

NCDs constitute a significant proportion of deaths in rural western Kenya. Evidence of the increasing contribution of NCDs to overall mortality supports international recommendations to introduce or enhance prevention, screening, diagnosis and treatment programmes in LMICs.

Prevalence and associated factors of hypertension among adults in Durame Town, Southern Ethiopia

Background

To date, non-communicable diseases, such as cardiovascular diseases, are becoming severe public health challenges particularly in developing countries. Hypertension is a modifiable risk factor that contributes the leading role for mortality. The problem is significant in low- and middle-income countries like sub-Saharan Africa. However, there are limited studies in developing countries, particularly in Ethiopia. Hence, determining the magnitude of hypertension and identifying risk groups are important.

Methods

A community based cross sectional study was conducted in April 2013 among adults (age>31 years) old. A systematic sampling technique was used to select a total of 518 study participants. Data were collected after full verbal informed consent was obtained from each participant. Multivariable logistic regressions were fitted to control the effect of confounding. Adjusted Odds ratios (OR) with their 95% confidence intervals (95% CI) were calculated to measure associations. Variables having P-value <0.05 were considered as significant.

Results

The overall prevalence of hypertension in Durame town was 22.4% (95% CI: 18.8–26.0). Nearly 40% of hypertensive patients were newly screened. Male sex [AOR  = 2.03, 95% CI; 1.05–3.93], age [AOR  = 29.49, 95% CI; 10.60–81.27], salt use [AOR  = 6.55, 95% CI; 2.31–18.53], eating vegetable three or fewer days per week [AOR  = 2.3,95% CI; 1.17–4.51], not continuously walking at least for 10 minutes per day [AOR  = 7.82, 95% CI; 2.37–25.82], having family history of hypertension [AOR  = 2.46, 95%CI; 1.31–4.61] and being overweight/obese [AOR  = 15.7, 95% CI 7.89–31.21)] were found to be risk factors for hypertension.

Conclusions

The prevalence of hypertension is found to be high. Older age, male sex, having family history of hypertension, physical inactivity, poor vegetable diet, additional salt consumption and obesity were important risk factors associated with hypertension among adults. Community level intervention measures with a particular emphasis on prevention by introducing lifestyle modifications are recommended.

Prevalence of hypertension and associated cardiovascular risk factors in an urban slum in Nairobi, Kenya: a population-based survey

BACKGROUND

Urbanisation has been described as a key driver of the evolving non-communicable disease (NCD) epidemic. In Africa, hypertension is the commonest cardiovascular problem. We determined the prevalence and risk factor correlates of hypertension in the largest Nairobi slum.

METHODS

In 2010 we conducted a population-based household survey in Kibera, a large informal settlement in Nairobi City; utilising cluster sampling with probability proportional to size. Households were selected using a random walk method. The WHO instrument for stepwise surveillance (STEPS) of chronic disease risk factors was administered by trained medical assistants, who also recorded blood pressure (BP) and anthropometric measures. BP was recorded using a mercury sphygmomanometer utilising the American Heart Association guidelines. Hypertension was defined as per the 7th Report of the Joint National Committee or use of prescribed antihypertensive medication. Those with hypertension or with random capillary blood sugar (RCBS) >11.1 mmol/l had an 8 hours fasting venous blood sugar sample drawn. Age standardised prevalence was computed and multivariate analysis to assess associations.

RESULTS

We screened 2200 and enrolled 2061 adults; 50.9% were males; mean age was 33.4 years and 87% had primary level education. The age-standardised prevalence of hypertension (95% CI) was 22.8% (20.7, 24.9). 20% (53/258) were aware of their hypertensive status; 59.3% had pre-hypertension; 80% reported high levels of physical activity and 52% were classified as harmful alcohol drinkers; 10% were current smokers and 5% had diabetes. Majority of males had normal BMI and waist circumference, whereas a third of females were obese or overweight and 40% had central obesity. Older age, higher general and central obesity were independently associated with hypertension and higher SBP and DBP readings.

CONCLUSIONS

Our findings of high prevalence of hypertension, in association with excess body weight in this poor urban slum community, point to the need for greater awareness and implementation of primary preventive strategies.