Epidemiology

Hypertension is a global public health issue (World Health Organization, 2013). With a growing and ageing global population, as many as 40% of adults aged 25 and over are thought to have hypertension (World Health Organization, 2013). In 2010, it was estimated that 1.39 billion people had hypertension, up from 594 million in 1975, and represented a 5.2% increase from 2000 (Bloch, 2016; NCD Risk Factor Collaboration, 2017). Meanwhile, a recent meta-analysis of 1,670 studies that included 29.5 million participants from across 71 countries identified a prevalence rate that ranged from 4–78% with a crude increase in prevalence observed since the year 2000 (Salem et al., 2018).

Increasing levels of hypertension are of significant concern because of its association with risk of cardiovascular (CV) disease. The lifetime risk of CV disease in a 30-year-old with hypertension is 63.3% compared with 46.1% in someone without hypertension (Rapsomaniki et al., 2014).

Hypertension was responsible for around 19% of global deaths and 7% of total disability-adjusted life years (World Health Organization, 2014; World Health Organization, 2017).


Importantly, hypertension does not just increase your risk of CV disease; high blood pressure is the primary cause of cardiovascular death (Figure 1) (Go et al., 2013).

High blood pressure is the primary cause of CV death (Go et al., 2013).

Figure 1: High blood pressure is the primary cause of CV death (Go et al., 2013).

Hypertension is a global issue, but it does not appear to affect all regions equally. 

Hypertension prevelance

Hypertension tends be more prevalent in low- and middle-income countries (LMICs) than high-income countries (HICs) with a prevalence of 28% in Nigeria and 29% in Russia, but only 13% in the USA (Figure 2) (World Health Organization, 2014). Recent data has also observed the highest hypertension prevalence rates shifting from higher middle-income countries to lower middle-income countries (Salem et al., 2018).

Prevalence of hypertension in countries around the world (World Health Organization, 2014).

Figure 2: Prevalence of hypertension in countries around the world (World Health Organization, 2014).

The effective management of hypertension can be achieved through lifestyle changes and medication. However, in many countries, control of hypertension remains suboptimal. In China, for example, a retrospective analysis of 45,108 individuals indicated that the prevalence of hypertension was high, but only 34.4% were receiving treatment and just 8.2% of patients were controlled (Li et al., 2016). A 2017 population-based study from China supported these findings. Among a population of 1.7 million participants aged between 35 and 75 years, 44.7% had hypertension, but less than half were aware of their diagnosis, just 30% were receiving treatment and only 7.2% had achieved control (Lu et al., 2017). Similar issues are seen on a global level with differences again observed between LMICs and HICs (Bloch, 2016):

  LMICs (2000–2010) HICs (2000–2010)
Awareness 32.3%–37.9% 58.2%–67.0%
Treatment 24.9%–29.0% 44.5%–55.6%
Control 8.4%–7.7%  17.9%–28.4%

The development and availability of antihypertensive agents including ACE inhibitors, angiotensin receptor blockers, calcium channel blockers, diuretics, as well as their combination into single-pill fixed combinations of two or three treatments with different modes of action, means hypertension can frequently be effectively managed. However, more still needs to be done to ensure patients receive the treatment they need. The World Heart Federation has set a target of improving global hypertension control rates by 25% by the year 2025. Achieving this goal will require substantial reduction in the disparity seen in hypertension awareness and treatment (Bloch, 2016). Furthermore, it requires improved awareness among physicians of the latest guidelines and treatment recommendations such as the use of single-pill fixed-dose combinations in the management of hypertension.

While currently available antihypertensive treatments can control many patients’ hypertension, it is important to acknowledge the presence of resistant hypertension in some patients. However, the number of patients with true-resistant hypertension may be lower than expected with many patients experiencing apparent treatment-resistant hypertension (uncontrolled disease despite use of ≥3 classes of antihypertensive therapy) and pseudo-resistant hypertension (controlled disease that appears uncontrolled). A meta-analysis of 91 studies that included a pooled sample of over 3 million patients with hypertension identified a prevalence of true-resistant hypertension of 10.3% (95% CI, 7.6%-13.2%). However, a significant number of patients were identified as having apparent treatment-resistant hypertension (14.7%; 95% CI, 13.1%-16.3%) and pseudo-resistant hypertension (10.3%; 95% CI, 6.0%-15.5%) highlighting the importance of excluding potential causes of pseudo-resistant hypertension such as “white-coat hypertension” (Noubiap et al., 2018). 

Within the Knowledge Centre, international experts on hypertension offer their personal thoughts on how hypertension management should be optimised.

References