From the Guidelines
Blood pressure increases with age primarily due to the progressive stiffening of central conduit arteries, such as the aorta and great vessels, which is associated with increased collagen cross-linking and degradation of elastin fibers, as noted in a study published in Circulation 1. This arterial stiffening is a key factor in the rise of systolic blood pressure with age, while diastolic blood pressure tends to plateau and then decline, resulting in a widened pulse pressure. Key factors contributing to this condition include:
- Aging-associated changes in the arteries, such as increased stiffness and the accumulation of arterial calcium
- Sedentary lifestyle and high salt diets, which exacerbate arterial stiffening
- Atherosclerosis, which narrows blood vessels and increases resistance to blood flow
- Hormonal changes that affect systems regulating blood pressure, such as the renin-angiotensin-aldosterone system
- Lifestyle factors, including poor diet, lack of exercise, increased sodium intake, and chronic stress. As highlighted in the study published in Circulation 1, the prevalence of hypertension increases with age, affecting approximately 70% of adults 75 years of age and older, with systolic blood pressure being a significant predictor of cardiovascular events. Therefore, maintaining a healthy lifestyle, including regular exercise, a balanced diet low in sodium, limited alcohol consumption, not smoking, and managing stress, is crucial in mitigating age-related increases in blood pressure, as supported by the findings of the HYVET Trial 1.
From the Research
Factors Contributing to Increased Blood Pressure with Age
- Arterial stiffness is a significant factor, as it increases with advancing age and is associated with increased systolic blood pressure 2, 3, 4
- Large artery stiffness is particularly relevant, as it leads to isolated systolic hypertension, the most common type of hypertension in older adults 2, 3, 4
- The mechanisms underlying age-related arterial stiffening are not fully understood but may involve components of the renin-angiotensin system, matrix metalloproteinases, intracellular signaling, and extracellular matrix components 2
- Increased renal sympathetic nerve activity (RSNA) may also play a role in the development of hypertension, particularly in the elderly 5, 6
- The kidney's role in controlling salt and water homeostasis makes it an important target for investigations into the development of hypertension 5, 6
Physiological Changes Associated with Aging
- Arterial compliance decreases with age, leading to increased pulse pressure and systolic blood pressure 2, 3, 4
- The anatomic changes of large arteries with aging, including increased stiffness, may contribute to the development of hypertension 4
- The role of age and gender on arterial stiffness and wave reflection has been poorly investigated, particularly in subjects over 70 years 4
Clinical Implications
- Treating elderly hypertensive patients can reduce the risk of cardiovascular events, but there is no evidence yet for the very elderly 3
- The reduction of blood pressure in the very elderly may result in increased mortality, highlighting the need for careful consideration of treatment strategies in this population 3