Age increases the risk of aneurysms primarily because of the gradual weakening and deterioration of blood vessel walls over time. As people get older, their arteries and blood vessels undergo structural changes that make them more vulnerable to developing aneurysms, which are abnormal bulges or balloon-like expansions in the vessel walls.
One of the main reasons for this increased risk is the natural breakdown of elastin and collagen, two key proteins that provide strength and elasticity to blood vessels. Elastin allows vessels to stretch and recoil with each heartbeat, while collagen provides structural support. With aging, elastin fibers degrade and collagen becomes stiffer, leading to less flexible and more fragile vessel walls. This makes it easier for the pressure of blood flow to cause a localized dilation or aneurysm.
Additionally, aging is often accompanied by other conditions that further weaken blood vessels. High blood pressure, which becomes more common with age, exerts extra force on artery walls, accelerating their wear and tear. Atherosclerosis, the buildup of fatty plaques inside arteries, also increases with age and contributes to vessel wall damage and inflammation. These plaques can erode the inner lining of arteries, making them more prone to aneurysm formation.
The cumulative effect of years of exposure to risk factors like smoking, hypertension, and inflammation compounds the damage to the vascular system. Smoking, in particular, damages the lining of arteries and promotes inflammation, accelerating the degradation of vessel walls. Since older adults are more likely to have a history of smoking or prolonged exposure to other harmful factors, their risk rises accordingly.
Genetic predisposition also plays a role, but the impact of age is independent and significant. Even without a family history, the structural changes in blood vessels due to aging alone increase aneurysm risk. This is why aneurysms are more commonly detected in people over 50 or 60 years old.
Women, especially postmenopausal women, face a higher risk as well. The decline in estrogen after menopause reduces the protective effects this hormone has on blood vessels, making vessel walls more susceptible to damage and aneurysm formation. This partly explains why women’s risk increases significantly after age 50.
Different types of aneurysms, such as brain aneurysms and abdominal aortic aneurysms, show this age-related pattern. For example, abdominal aortic aneurysms are rare in younger people but become much more common after age 65, particularly in men with a history of smoking or hypertension. Brain aneurysms also tend to develop silently over many years and are more frequently diagnosed in middle-aged and older adults.
In summary, aging increases aneurysm risk because it causes:
– **Degeneration of elastin and collagen** in vessel walls, reducing elasticity and strength.
– **Increased arterial stiffness and fragility**, making vessels prone to bulging.
– **Higher prevalence of hypertension and atherosclerosis**, which damage vessel walls.
– **Cumulative exposure to harmful factors** like smoking and inflammation over time.
– **Hormonal changes in women** after menopause that reduce vascular protection.
These factors combine to weaken blood vessels progressively, making aneurysms more likely to form and potentially rupture as people grow older. This is why screening and monitoring for aneurysms become more important with advancing age, especially for individuals with additional risk factors.