Hypertension, Ischaemic Stroke and Transient Ischaemic Attack

There are over 7.6 million new ischaemic strokes each year, and 3.3 million people die from ischaemic stroke annually. Elevated blood pressure (BP) is the strongest population-attributable preventable and modifiable risk factor for stroke. Increased BP variability is as important as hypertension for the risk of ischaemic stroke, recurrent ischaemic stroke, cardiovascular (CV) and renal events, and all-cause death. The presence of risk factors (i.e. current smoking, alcohol consumption, dyslipidaemia, lack of physical activity, stress, depression), single or combined comorbidities (i.e. obesity, diabetes, atrial fibrillation, sleep apnoea) can potentially interact, causing structural and functional changes in the brain beyond their impact on the stroke incident. Ageing is a strong non-modifiable risk factor for incident stroke, which doubles every 10 years after the age of 55. The risk of stroke is particularly high in people with previous stroke or transient ischaemic attack (TIA). TIA is caused by a temporary disruption of the blood supply to the parts of the brain, with noticeable symptoms usually lasting from a few minutes to 24 h, making diagnosis challenging. TIAs are often neglected due to symptoms that tend to subside. However, TIA is a strong predictor of major future stroke and requires careful evaluation to identify high-risk patients properly. Advances in CV and brain imaging have importantly contributed to the precise identification of stroke subtypes likely leading to improved patient outcomes. Therefore, increased awareness, identification of high-risk individuals and timely treatment can substantially reduce the risk of stroke. Although BP lowering is an effective approach to reduce the burden of stroke in hypertensive and high-risk patients, available evidence indicates that not all stroke subtypes are caused by established hypertension.