Prevalence, treatment, and control of hypertension in primary care: gaps, trends, and opportunities

Since most cases of hypertension are managed in family practice, estimates of the prevalence, treatment, and control in the primary care population are needed to adequately address the burden of hypertension in Canada as it has in other countries. The authors used a large primary care research database to determine the prevalence of hypertension between 2000 and 2003. Blood pressure recordings were used to estimate the rates of prevalence, treatment, and control of hypertension for the overall population and for important subgroups. The prevalence of hypertension was 17.3%, most patients had untreated hypertension (68.6%), and only 15.8% had blood pressure treated and controlled. Higher rates of treatment and control were observed among older adults, those with type II diabetes, and those with a previous myocardial infarction. Odds of achieving target blood pressure were significantly better when combination therapy vs monotherapy was used. The prevalence of hypertension in primary care is high and most patients remain untreated; however, increased risk appears to lead to better treatment and control.     

Risk factors associated with uncontrolled hypertension: findings from the baseline CARMEN survey in Cienfuegos, Cuba

OBJECTIVES: Identifying methods to improve pharmacologic control of elevated blood pressure remains the most urgent challenge in clinical research on hypertension. The probability of having inadequate control varies widely in the population and better understanding of the factors responsible could help to focus treatment strategies. METHODS: A population-based community survey of 1475 persons aged 25-74 years, in Cienfuegos, Cuba, was used to identify these factors in a low-resource setting. RESULTS: While half of women with hypertension were controlled, only one-third of men were receiving successful treatment. Gender differences were not seen, however, among those currently taking medications. The largest burden of hypertension in absolute terms was concentrated in the age range 45-64, emphasizing the heavy burden of uncontrolled high blood pressure that falls on middle-aged men. Race-ethnicity was not a determinant of treatment and control status, nor was inability to obtain medication. CONCLUSIONS: These findings largely confirm the pattern observed in industrialized countries and demonstrate the near-universal challenge confronting primary-care systems in physician-based control of cardiovascular risk factors.     

Resources for mental health: scarcity, inequity, and inefficiency

Resources for mental health include policy and infrastructure within countries, mental health services, community resources, human resources, and funding. We discuss here the general availability of these resources, especially in low-income and middle-income countries. Government spending on mental health in most of the relevant countries is far lower than is needed, based on the proportionate burden of mental disorders and the availability of cost-effective and affordable interventions. The poorest countries spend the lowest percentages of their overall health budgets on mental health. Most care is now institutionally based, and the transition to community care would require additional funds that have not been made available in most countries. Human resources available for mental health care in most low-income and middle-income countries are very limited, and shortages are likely to persist. Not only are resources for mental health scarce, they are also inequitably distributed-between countries, between regions, and within communities. Populations with high rates of socioeconomic deprivation have the highest need for mental health care, but the lowest access to it. Stigma about mental disorders also constrains use of available resources. People with mental illnesses are also vulnerable to abuse of their human rights. Inefficiencies in the use of available resources for mental health care include allocative and technical inefficiencies in financing mechanisms and interventions, and an overconcentration of resources in large institutions. Scarcity of available resources, inequities in their distribution, and inefficiencies in their use pose the three main obstacles to better mental health, especially in low-income and middle-income countries.     

Silica, silicosis and tuberculosis.

Exposure to crystalline silica dust causes multiple diseases, but silicosis and silica dust-associated tuberculosis (TB), in particular, are the two diseases that remain high on the list of occupational health priorities in low-income countries and that still occur in some high-income countries. The prevalence of silica-related TB is exacerbated by the human immunodeficiency virus (HIV) epidemic in low-income countries. This review describes the morphology of silica and the variable potency of the different forms. Sources of crystalline silica are discussed, with emphasis on less commonly recognised sources, such as small-scale mining operations and agriculture. Trends in the prevalence of silicosis are also presented. Although efforts have been made for many years in most countries to reduce silica dust levels, silicosis continues to occur even in young people. The clinical and pathological features and diagnosis of silicosis, with emphasis on chest radiography, are described. The high risk of mycobacterial infection in silica-exposed individuals is given particular attention, with emphasis on control. Treatment for latent TB is recommended. The management of silicosis and silica-associated TB, including monitoring for early detection of disease and surveillance to identify disease-causing workplaces, are discussed in detail. Prevention of disease, in the form of dust control, remains the focus of the World Health Organization and International Labour Office Global Elimination of Silicosis Campaign. However, clinicians must be aware that silica-associated diseases will be around for many years to come.     

Public-private partnerships to reduce tobacco dependence

Four-fifths of the estimated one billion deaths that will be caused by tobacco dependence over the next 100 years will occur in low-income countries. Along with other tobacco control policy measures, the treatment for tobacco dependence is a cost-effective policy measure in low-income countries. In public health, public-private partnerships for drugs and vaccines and incentives for commercial private sector engagement are proposed to tackle the communicable diseases of the poor. This paper will argue that public-private partnerships are also an appropriate and important vehicle to reduce the harm caused by tobacco. For the pharmaceutical sector to engage in the marketing of tobacco dependence treatment products in low-income countries the incentives must be aligned, and a self-sustaining market must be developed. A rational market would be large, characterized by high volumes and low margins. The framework convention on tobacco control of the WHO provides a global infrastructure for taking public sector action to reduce the harm caused by tobacco. The convention could call for a proportion of tobacco tax from high-income countries to be used to fund tax credits and other incentives for increasing the access to tobacco dependence treatment in low-income countries.     

Outpatient hypertension treatment, treatment intensification, and control in Western Europe and the United States

BACKGROUND: Hypertension guidelines in the United States tend to have more aggressive treatment recommendations than those in European countries. METHODS: To explore international differences in hypertension treatment, treatment intensification, and hypertension control in western Europe and the United States, we conducted cross-sectional analyses of the nationally representative CardioMonitor 2004 survey, which included 21 053 hypertensive patients visiting 291 cardiologists and 1284 primary care physicians in 5 western European countries and the United States. The main outcome measures were latest systolic and diastolic blood pressure (BP) levels, hypertension control (latest BP level, <140/90 mm Hg), and medication increase (dose escalation or an addition to or switch of drug therapy) for inadequately controlled hypertension. RESULTS: At least 92% of patients in each country received antihypertensive drug treatment. The initial pretreatment BP levels were lowest and the use of combination drug therapy (>or=2 antihypertensive drug classes) was highest in the United States. Multivariate analyses controlling for age, sex, current smoking, and physician specialty indicated that, compared with US patients, European patients had higher latest systolic BP levels (by 5.3-10.2 mm Hg across countries examined) and diastolic BP levels (by 1.9-5.3 mm Hg), a smaller likelihood of hypertension control (odds ratios, 0.27-0.50), and a smaller likelihood of medication increase for inadequately controlled hypertension (odds ratios, 0.29-0.65) (all P<.001). In addition, controlling for initial pretreatment BP level attenuated the differences in latest systolic and diastolic BP levels and the likelihood of hypertension control. CONCLUSION: Lower treatment thresholds and more intensive treatment contribute to better hypertension control in the United States compared with the western European countries studied.     

Prevalence, awareness, treatment and control of hypertension in North America, North Africa and Asia

Results from national surveys of prevalence, awareness, treatment and control provide the most meaningful basis for assessing the burden of hypertension in the community. National surveys conducted in a variety of countries in North America, Europe, Australia, Asia and Africa have identified a strikingly similar relationship between age and blood pressure (BP), with a progressive and steep increase in systolic BP throughout adult life and a less steep increase in diastolic BP from adolescence until the fifth or sixth decade. In most countries surveyed, there was a high prevalence of hypertension. Approximately, one quarter of all adults in the United States and Egypt had hypertension (systolic BP>/=140 mmHg or diastolic BP>/=90 mmHg or use of antihypertensive medication) in national surveys conducted in 1988-1991 and 1991-1993, respectively. The corresponding percentage was somewhat lower (14.4%) for adults surveyed in China during 1991, but temporal trends indicate that the prevalence of hypertension is increasing rapidly in that country. In the 1988-1991 national survey, more than 25% of US adults were unaware of their diagnosis, only 55% were being treated with antihypertensive medication and only 29% were on antihypertensive medication with a systolic/diastolic BP >140/90 mmHg. The situation was much worse in Egypt and China, with only 8% and <5% of adults with hypertension, respectively, being treated with antihypertensive medication and having a systolic/diastolic BP <140/90 mmHg. These survey results underscore the fact that hypertension is highly prevalent, poorly treated and controlled, and an escalating health challenge in economically developing countries.     

Treatment and disease outcomes of migrants from low- and middle-income countries in the Australian HIV Observational Database cohort

People from culturally and linguistically diverse backgrounds, including low- and middle-income countries, account for a third of new HIV diagnoses in Australia and are a priority for HIV prevention and treatment programs. We describe the demographic and clinical characteristics of participants in the Australian HIV Observational Database (AHOD) and compare disease outcomes, progression to AIDS and treatment outcomes of those born in low- and middle-income countries, with those born in high-income countries and Australia. All participants enrolled in AHOD sites where country of birth is routinely collected were included in the study. Age, CD4 count, HIV viral load, antiretroviral therapy, hepatitis co-infection, all-cause mortality and AIDS illness were analysed. Of 2403 eligible participants, 77.3% were Australian born, 13.7% born in high-income countries and 9.0% born in middle- or low-income countries. Those born in Australia or high-income countries were more likely to be male (96%) than those from middle- or low-income countries (76%), p?p?p?p?=?.19.There was no difference in adjusted incidence risk ratios for all-cause mortality and AIDS incidence in all three groups, p?=?.39. These findings reflect successful outcomes of people born in low- and middle-income countries once engaged in HIV care.     

Hypertension and chronic kidney disease in Asian populations

The countries of Asia are home to multiple ethnicities. There are ethnic differences in diet, culture, and attitudes towards health screening, access to care, and treatment of chronic diseases. Chronic kidney disease (CKD) and end‐stage kidney disease (ESKD) have rising incidence and prevalence due to increased affliction with non‐communicable diseases of diabetes and hypertension. To prevent the expensive complications of ESKD, one of the most important risk factors to control is hypertension in patients with CKD. We performed a narrative review on the prevalence of CKD in patients with hypertension, the prevalence and control of hypertension in patients with CKD, and the dietary sodium intake in CKD populations.     

Hypertension and cardiovascular health in Venezuela and Latin American countries

Since 1950 all countries of the Latin-American subcontinent have experienced very important changes in several health indicators, in the demographic, epidemiological, socio-cultural and way of living profiles. The proportion of the population over 65 years old tend to be low in the Latin American countries in contrast to developed countries. Cardiovascular diseases are the main cause of death in most of the Latin American countries at a similar rate to that of the developed world. As infectious diseases are reduced, cardiovascular diseases takes their place as the main cause of death in Latin American countries. Prevalence of hypertension in different reports show variations from 40 to 8% in the adult population, but on average 20 to 23% of the adult population have elevated blood pressure. This prevalence is similar to reports in the developed world. However there is considerable variability in each country and its regions so it is important that local studies of prevalence and local factors in the development of hypertension are investigated. The degree of awareness, treatment and control of hypertension is lower than that reported in the developed world, and it is important to establish programmes to attend to this public health problem, from prevention to treatment, from primary care to higher levels of attention.     

World Health Organization (WHO) and International Society of Hypertension (ISH) risk prediction charts: assessment of cardiovascular risk for prevention and control of cardiovascular disease in low and middle-income countries

Cardiovascular disease (CVD) is the leading cause of the growing global disease burden due to non-communicable diseases. For successful prevention and control of CVD, strategies that focus on individuals need to complement population-wide strategies. Strategies that focus on individuals are cost effective only when targeted at high-risk groups. Risk prediction tools that easily and accurately predict an individual's absolute risk of CVD are key to targeting limited resources at high-risk individuals who are likely to benefit the most. Health systems in low-income countries do not have the basic infrastructure facilities to support resource-intensive risk prediction tools, particularly in primary healthcare. The WHO/ISH charts presented here, enable the prediction of future risk of heart attacks and strokes in people living in low and middle income countries, for the first time. Furthermore, since the charts use simple variables they can be applied even in low resource settings. Thus the WHO/ISH risk predication charts and the accompanying guideline will improve the effectiveness of cardiovascular risk management even in settings which do not have sophisticated technology.     

Study of Prevalence, Awareness,and control of Hypertension in a Suburban Area of Kathmandu, Nepal

BACKGROUND, In the context of rapidly raising occurrence of cardiovascular diseases in the developing countries, it becomes imperative to study the scenario in its various aspects. The present study in Nepal deals with the hypertension as it is one of the major risk factors of cardiovascular diseases. METHODS AND RESULTS, A house-to-house survey was conducted in a suburban area of Kathmandu valley from February to June 2005 in adult population (age >/=18 years) to estimate the prevalence, awareness, treatment, and control rates of hypertension. Blood pressure was measured twice using standardized mercury sphygmomanometer, and an average of the two readings was taken. Total number of subjects were 1114 (men:541; women: 573; mean age: 37.8 -/+ 16.3 years). Overall prevalence of hypertension was 19.7% (22.2% in men and 17.3% in women, p < 0.05).Prevalence of hypertension in age group of >/=40 years was 36%.Awareness, treatment, and control rates were 41.1%, 26%, and 6%, respectively. CONCLUSION, Our study indicates that prevalence of hypertension is significant in Nepal and is comparable with other developing countries of this region. Awareness, treatment, and control rates are poor.     

Hypertension in developing economies: a review of population-based studies carried out from 1980 to 1998

AIM: Hypertension is an established major risk factor underlying the epidemic of coronary and cardiovascular diseases in most developed countries, and it has been shown to be a public health problem in many developing countries since the 1970s. This review was carried out to illustrate the current situation with regard to blood pressure levels and the prevalence and management of hypertension in developing countries. METHODS: A search for papers published in medical journals from 1991 to 1998 was performed using the MEDLINE database. A total of 40 articles were selected according to previously defined criteria. RESULTS: Hypertension is a public health problem for most of the developing countries reviewed, and it is frequently associated with low levels of awareness, treatment and control. A positive association between the gross national product per capita and the prevalence of hypertension in developing countries is also evident. CONCLUSIONS: Differences in methodology between national surveys make international comparisons difficult. Nevertheless, low-cost hypertension control programmes in developing countries are needed, along with development of the primary prevention of hypertension.     

ADVANCE: action in diabetes and vascular disease

The burden of Type II diabetes is growing rapidly worldwide, across high-, middle- and low-income countries. This burden is associated primarily with increased risks of macrovascular and microvascular diseases, and it is agreed that multifactorial treatment regimens are required to reduce it. ADVANCE (Action in Diabetes and Vascular disease: Preterax and Diamicron-MR Controlled Evaluation) is a large-scale, 2 x 2 factorial, randomised clinical trial. It will investigate the potential benefits of blood pressure lowering, using a fixed low-dose combination of perindopril and indapamide vs placebo, and of tighter glucose control, using an intensive gliclazide-MR-based glucose control regimen vs a standard guidelines-based regimen, separately and together. The two primary outcomes are a composite macrovascular end point of nonfatal stroke, nonfatal myocardial infarction and cardiovascular death; and a composite microvascular end point of new or worsening nephropathy or microvascular eye disease. Following successful recruitment and randomisation of 11,140 participants by March 2003, the study is currently half way through its planned follow-up of 4.5 years. Adherence to randomised study treatment is good; and loss to follow-up is minimal. It is hoped that the study will answer a number of unresolved issues. The blood pressure lowering arm will investigate the possible reduction in major vascular disease in patients with Type II diabetes whether or not they have hypertension, and the possible benefits of blood pressure lowering in such patients already receiving background therapy with the ACE inhibitor perindopril. The glucose control arm will investigate the possible reduction in both macrovascular and microvascular disease achieved with tighter glucose control, targeting an HbA1c of 6.5% and a fasting blood glucose of 6.0 mmol/l. Finally, the factorial design will enable investigation of the combined effects of more intensive glucose control and tighter control of blood pressure.     

Prevalence,Awareness, Treatment,and Control of Hypertension in Lebanon

The prevalence and factors related to hypertension (HTN) treatment and control are well investigated in the Western world but remain poorly understood in the Middle East and in middle‐income countries such as Lebanon. In order to measure the prevalence, awareness, treatment, and control rates of HTN in Lebanon, the authors measured blood pressure (BP) in 1697 adults. The prevalence of optimal BP (<120/80 mm Hg) was 33% and that of pre‐HTN (BP ≥120/80 mm Hg but <140/90 mm Hg) was 30%. The prevalence, awareness, treatment, and control (among treated hypertensive) rates of HTN were 36.9%, 53%, 48.9%, and 54.2%, respectively. Overall, only 27% of patients with HTN had their BP under control. Awareness was the most important predictor of treatment. No predictor of control could be identified. The authors concluded that HTN is prevalent in Lebanon and its overall control is low. Improving awareness is the most important target for intervention.     

Tobacco use,cancer causation and public health impact

This review describes global patterns of tobacco use and the mechanisms by which tobacco use is involved in carcinogenesis. A second part will discuss the association between tobacco use and risk of specific cancer types. Tobacco use has traditionally been a practice of high-income countries, but it has recently been taken up in low-income countries and it is particularly common in men. A wide variety of tobacco products exist, of which cigarettes are most frequently consumed. Tobacco products contain more than 50 established or identified carcinogens and these may increase risk of cancer by causing mutations that disrupt cell cycle regulation, or through their effect on the immune or endocrine systems. Certain factors such as genes, diet and environmental exposures may alter susceptibility to cancer in tobacco users. Today at least 15% of all cancers are estimated to be attributable to smoking, but this figure is expected to increase because of the uptake of tobacco use in low-income countries.     

HIV, aging and continuity care: strengthening health systems to support services for noncommunicable diseases in low-income countries

Although health systems in most low-income countries largely provide episodic care for acute symptomatic conditions, many HIV programs have developed effective, locally owned and contextually appropriate policies, systems and tools to support chronic care services for persons living with HIV (PLWH). The continuity of care provided by such programs may be especially critical for older PLWH, who are at risk for more rapid progression of disease and are more likely to have complications of HIV and its treatment than their younger counterparts. Older PLWH are also more likely to have other chronic noncommunicable diseases (NCDs), including hypertension, diabetes, cancers and chronic lung disease. As the number of older PLWH rises, enhanced chronic care systems will be required to optimize their health and wellbeing. These systems, lessons and resources can also be leveraged to support the burgeoning numbers of HIV-negative individuals with chronic NCD in need of ongoing care.     

Burkitt's lymphoma

Burkitt's lymphoma is a highly aggressive B-cell non-Hodgkin lymphoma and is the fastest growing human tumour. The disease is associated with Epstein-Barr virus and was one of the first tumours shown to have a chromosomal translocation that activates an oncogene (c-MYC). Burkitt's lymphoma is the most common childhood cancer in areas where malaria is holoendemic. The incidence is very high in immunosuppressed patients in non-endemic areas, especially when associated with HIV infection. Outcome with intensive chemotherapy has improved and is now excellent in children, but the prognosis is poor in elderly adults. The success of intensive treatment relies on good supportive care. The therapy offered in oncology units in low-income countries is not as aggressive as in centres in high-income countries and outcomes are less successful. Adjuvant monoclonal antibody therapy with rituximab shows promise for improved outcomes and reduced toxic effects in the future.     

Awareness, treatment and control of hypertension: the 'rule of halves' in an era of risk-based treatment of hypertension

Detection, treatment and control of high blood pressure in many populations are insufficient. We reported current prevalence, awareness, treatment and control of hypertension in the Netherlands and compared the findings with other studies. Furthermore, we related actual treatment of hypertension to estimated absolute 10-year cardiovascular risk, as according to current guidelines on this subject, initiation of blood pressure-lowering treatment depends on the level of cardiovascular risk. The Utrecht Health Project is a prospective cohort study in a suburb of Utrecht. Information on medical history, life style and measurements of blood pressure, cholesterol and glucose of the first 4950 participants of the study was obtained. Cardiovascular risks were calculated using the Framingham risk function. Prevalence of hypertension was 23.3%. Among those with hypertension, 33.7% was aware of the condition. Of those aware, 59.4% was treated. Of those treated, 41.9% had blood pressure below the recommended level. In half of those aware of their hypertension, and a calculated cardiovascular risk less than 10%, treatment of hypertension was started unnecessary. Of those aware of their hypertension with a calculated cardiovascular 10 years risk exceeding the treatment threshold of 20%, treatment was absent in 33.6%. Awareness and control of hypertension are still inadequate in the Netherlands and comparable with other European countries. Management of hypertension is too often not risk-based despite recommendations in guidelines on prevention of cardiovascular diseases available since 2000.     

Monitoring and surveillance of chronic non-communicable diseases: progress and capacity in high-burden countries

The burden of chronic, non-communicable diseases in low-income and middle-income countries is increasing. We outline a framework for monitoring of such diseases and review the mortality burden and the capacity of countries to respond to them. We show data from WHO data sources and published work for prevalence of tobacco use, overweight, and cause-specific mortality in 23 low-income and middle-income countries with a high burden of non-communicable disease. Data for national capacity for chronic disease prevention and control were generated from a global assessment that was done in WHO member states in 2009-10. Although reliable data for cause-specific mortality are scarce, non-communicable diseases were estimated to be responsible for 23·4 million (or 64% of the total) deaths in the 23 countries that we analysed, with 47% occurring in people who were younger than 70 years. Tobacco use and overweight are common in most of the countries and populations we examined, but coverage of cost-effective interventions to reduce these risk factors is low. Capacity for prevention and control of non-communicable diseases, including monitoring and surveillance operations nationally, is inadequate. A surveillance framework, including a minimum set of indicators covering exposures and outcomes, is essential for policy development and assessment and for monitoring of trends in disease. Technical, human, and fiscal resource constraints are major impediments to the establishment of effective prevention and control programmes. Despite increasing awareness and commitment to address chronic disease, concrete actions by global partners to plan and implement cost-effective interventions are inadequate.