Hypertension and the Brain: Understanding the Mechanisms Linking Elevated Blood Pressure to Stroke, Small Vessel Disease and Cognitive Decline

Abstract

Hypertension remains one of the most prevalent and modifiable risk factors for cerebrovascular diseases, contributing substantially to global morbidity and mortality. The persistent elevation of blood pressure initiates complex pathophysiological cascades that compromise vascular integrity and cerebral function. This review synthesises current evidence on the mechanisms linking hypertension to cerebrovascular disease, underscoring the importance of integrated prevention and treatment strategies to mitigate brain injury and preserve cognitive health. Chronic hypertension induces endothelial dysfunction, arterial remodelling, and increased arterial stiffness, leading to impaired autoregulation of cerebral blood flow. These vascular changes heighten the susceptibility to ischemic stroke, intracerebral haemorrhage, and vascular cognitive impairment. Furthermore, hypertension accelerates small vessel disease through mechanisms such as lipohyalinosis, microatheroma formation, and disruption of the blood–brain barrier, which collectively result in white matter lesions and microbleeds. Beyond structural damage, hypertension promotes neuroinflammation, oxidative stress, and impaired neurovascular coupling, thereby exacerbating neuronal injury and functional decline. Emerging evidence also implicates interactions between hypertension and neurodegenerative processes, including amyloid deposition and tau pathology, highlighting its role in dementia syndromes such as Alzheimer’s disease and vascular dementia. Despite the established relationship between elevated blood pressure and cerebrovascular pathology, the precise mechanistic links remain under investigation, with genetic, epigenetic, and lifestyle factors influencing individual susceptibility. Early diagnosis, aggressive blood pressure control, and the use of renin–angiotensin system inhibitors, calcium channel blockers, and other antihypertensive agents have demonstrated effectiveness in reducing the burden of cerebrovascular complications. Novel therapeutic strategies targeting endothelial health, neuroinflammation, and vascular remodelling are under exploration, offering promising directions for future management.