Know your blood pressure; the theme of world hypertension day 2014.

Dear Editor-in-Chief

Firstly World Hypertension Day (WHD) inaugurated in May 2005 and has become an annual event ever since (1).

The aim of the WHD is to promote public alertness of high blood pressure and to promote citizens of all countries to prevent and control this soundless killer, the modern epidemic (1). WHD was initiated firstly by the World Hypertension League (1).

High blood pressure (hypertension) is considered as the silent killer since it has no apparent symptoms. Investigations show that the disease involves more than 1.5 billion people global, and around seven million people die every year from hypertension (1–5).

The average rate of high blood pressure in men is 28.6% whereas it is about 23.9% in women. Firstly WHD inaugurated in May 2005 and has become an annual event ever since, then WHO devoted the 17th of May of every year to be the WHD to emphasize the hazards of this disease and to spread recognizing and alertness, which prevention is the main strategy to avoid various health risks linked to high blood pressure like heart and kidney diseases (1, 5). It is evident that long-term untreated hypertension can damage the arteries and vital organs through the body, leading to renal disease, heart disease, stroke, and other serious vision disorders (1, 5, 6).

Generally, it is thought that hypertension is the biggest single risk factor for death worldwide. Several recent studies from various continents have detected the higher prevalence of hypertension in the urban versus rural population. Urbanization usually is associated with increased income and adoption of an unhealthy lifestyle (4–7).

Generally, risk factors underlying the emergence of high blood pressure and related complications in the developing countries follow the similar pattern as those recognized in the developed world. Education and greater wealth seem to have a strong impact on the risk of high blood pressure, while this association may be confounded by lifestyle factors. Alongside with urbanization and improved income, there is a desire for modern suitability, like the adoption of unhealthy food habits with the alteration from traditional rural diets with a low glycemic index and a higher fiber content to a food rich in salt, saturated fats, and poor-quality carbohydrates such as fast foods (1, 5, 6–9). Furthermore, diminished physical activity and inactive occupations may be important risk factors for high blood pressure. Unfortunately, many investigations show that alertness of high blood pressure in the developing world population is low. In part, this likely reflects a low quantity of literacy and education. However it also appears to reflect a low level of access to medical care. Hence, WHO has taken a lead role in the progress of global strategies for the prevention of the noncommunicable diseases, like high blood pressure, and their risk factors (10–15). In fact, in developing populations, inadequate funds, and inexperience, are main barriers to high blood pressure diagnosis and therapy. There often is competition for limited financial resources with other important communicable causes of mortality and morbidity for example, malaria, HIV/AIDS, and tuberculosis. Additionally, money allocated to public health initiatives is much less than that in Western countries (1, 5, 12–15) All together, these clarifications for the limited progress achieved to date should justify a more intensive collaborative approach to manage high blood pressure. One of the messages of WHD is lifestyle change, like increasing exercise and decreasing consumption of calorie-dense and fat-rich diets salt and tobacco will help prevent the development of advanced stages of high blood pressure. Smoking is a preventable cause of high blood pressure, and increasing alertness of the harmful effects of smoking should be more vigorously promoted (10–18). One of the under noticed items in the development of hypertension is nutritional and other exogenous environmental factors during development which may permanently affect the fetus in uterus. There is some evidences that low birth weight (LBW) and intrauterine growth restriction (IUGR) are associated with a greater risk of high blood pressure (6, 15–20).

Investigations have reported higher blood pressures in adults born with LBW, even after adjusting for some factors like, parental blood pressure, smoking, oral contraceptive use, current weight, and gender (12–22). It is assumed that low birth weight resulting to reduced nephron number may be one of the main factors in the development of high blood pressure in later life (12–20). Then compensatory adaptation mechanisms following reduced proportion of nephron numbers consisting of glomerular hypertension, glomerular hyper-filtration and glomerular sclerosis well happened. These lesions might be worsened more by programmed alterations in renal vascular structure, kidney function and modifications in endocrine and metabolic homeostasis (1, 5, 6, 20–22). Indeed, it was suggested that LBW may have longer term effects on the risk of high blood pressure. In developing country populations, nutritional deficit commonly persists into early childhood and even later. In fact, it is possible that early childhood growth patterns affect blood pressure in adulthood. Interestingly, it is possible that high blood pressure at old age is associated with size at birth and growth and development during early childhood (1, 5, 6, 20–23).

In sum, optimal management of high blood pressure is important in preventing the risk of cardiovascular and renal diseases. Measurement of estimated glomerular filtration rate (eGFR), along with urine protein, preferably albumin, principally in patients with high blood pressure, is important for the early detection of renal disease. Appropriate treatment, largely targeting systolic blood pressure, has been encouraged. It should be noted that, treatment of systolic blood pressure ≥ 140 mm Hg mostly by renoprotective agents is our main stay as a nephrology point of view (1, 5, 6, 20–23). Finally more and more countries are linking to the World Hypertension Day each year to promote alertness, prevention and control of high blood pressure.

The success of World Hypertension Day is due to the interest and voluntary action of various participants from each member country. We hope that, this combination of public and private stakeholders will continue to contribute to the realization of WHD aim and, hence, to improve high blood pressure control worldwide.