Editorial

Hypertension is a global public health challenge affecting approximately 1.5 billion people worldwide and is the premiere modifiable risk factor for strokes and other cardiovascular diseases (CVDs).1 Although effective lifestyle and drug treatments are available for the management of hypertension, blood pressure (BP) control is suboptimal worldwide and the greatest burden of uncontrolled BP is reported in low and middle-income countries (LMICs) where rates of CVDs are rapidly rising.2 3 The need for improvement in hypertension control is particularly urgent in LMICs with two-thirds of global burden of hypertension.4 For instance, sub-Saharan Africa is now reported to have the highest estimated effect size of hypertension for stroke causation worldwide.5 The population attributable risk (PAR) of hypertension for stroke occurrence in Africa from the Stroke Investigative Research & Educational Networks study is 90.8% (95% CI 87.9% to 93.7%), with 86.6% (95% CI 81.6% to 91.6%) being for ischaemic stroke and 96.6% (95% CI 94.4% to 98.9%) for haemorrhagic stroke.5 These background observations highlight the importance of hypertension for stroke occurrence in regions of the world with severely challenged health systems to provide the needed care for the devastating consequences of uncontrolled hypertension. It has been suggested that differences in levels of knowledge, awareness and treatment of hypertension across regional blocks of the world may influence the occurrence of CVDs emanating from uncontrolled hypertension, in particular stroke. However, no previous study has provided rigorous evidence to support this view.

In their study, O’Donnell and colleagues sought to provide empirical evidence to substantiate …