Hypertension: Risks and Prevalence

When an individual is diagnosed with hypertension, it indicates that their average arterial pressure surpasses the accepted normal range. The increase in blood pressure raises significant health concerns for three primary reasons: its widespread prevalence, potential adverse consequences, and the likelihood of symptoms going unnoticed even in the later stages of clinical progression.

The negative effects of hypertension are diverse, affecting various organs, and it stands as the primary and most substantial risk factor for both coronary heart attacks and cerebrovascular diseases. Additionally, it can directly contribute to congestive heart failure and renal inadequacy. The absence of a specific threshold value underscores the gradual nature of the risk, escalating with the harmful effects of elevated blood pressure. Consequently, the evaluation of hypertension needs to be approached subjectively. While some advocate for diastolic pressure consistently exceeding 90 mmHg as a fundamental criterion, defining systolic pressure consistently at 140 mmHg as hypertension results in varying clinical outcomes for different reasons.

Using these criteria as a foundation, an extensive scanning program reveals that approximately 25% of the general population is affected by hypertension. However, despite the systolic and diastolic values set as limits for adults being 160/95, the prevalence is unexpectedly found to be 18% in this program. Although hypertension tends to be more severe in young adults, its frequency increases with age.

Around 90% of hypertension cases are idiopathic, classified as primary (essential) hypertension. The remaining 10%, mostly secondary, are associated with renal diseases and coarctation of the renal artery (renovascular hypertension), typically triggered by an atheroma plaque. Secondary hypertension may also develop at a low rate due to primary aldosteronism and certain adrenal disorders such as Cushing's syndrome and pheochromocytoma.
Hypertension: Risks and Prevalence

Renovascular hypertension

In most Westernized countries, and especially among older individuals, renovascular hypertension is the most remediable cause of elevated blood pressure.

Renovascular hypertension is a reversible cause of hypertension secondary to a decrease in renal perfusion pressure which activates the renin-angiotensin system and leads to the release of rennin and the production of angiotensin II.  It is a progressive disorder that can result in serious complications without adequate treatment.

Angiotensin II increases sodium reabsorption and induces postglomeruler and systemic arterial vasoconstriction, causing renovascular hypertension. The prevalence of renovascular hypertension was estimated at about 5% of all hypertensive individuals but it is varied form less than 1% to more than 50% depending on the degree of screening in the study population.

With prevalence of about 5%, renovascular disease represents the most frequent cause of secondary hypertension.

Unlike the diagnosis of most other cardiovascular and nephorologic conditions, renovascular hypertension can be diagnosed only retrospectively, by means of a physiologic blood pressure (BP) response to an intervention.
Renovascular hypertension

Idiopathic pulmonary arterial hypertension

Primary arterial hypertension is and has often been classified into two separate categories: primary pulmonary (arterial) hypertension, and secondary pulmonary arterial hypertension.

The term ‘primary’ pulmonary hypertension was replaced by ‘idiopathic’ pulmonary hypertension and when there was a genetic basis, ‘familial’ pulmonary hypertension.

Primary hypertension that occurred along with other conditions was referred to as ‘associated’ pulmonary hypertension.

Idiopathic pulmonary arterial hypertension is highly morbid disease characterized by progressive obliteration of precapillary arterioles.

The disease manifested by progressive pulmonary vascular remodeling, compromised pulmonary blood flow and right heart failure.

Idiopathic pulmonary arterial hypertension is rare, occurring in one to two cases per one million people per year, with an overall prevalence estimated at 1300 per one million.

According to World Health Organization (WHO) estimated, there are 5000 patients with Idiopathic pulmonary arterial hypertension in the United States and Europe. However, the prevalence may be increased because of heightened awareness and early recognition in minimally symptomatic patients.
Idiopathic pulmonary arterial hypertension