What Women Should Know about Alzheimer’s Disease

By Maria Carrillo, PhD
Scientific Director, Alzheimer’s Association

Alzheimer’s disease (AD) is the most common cause of dementia, affecting more than 5 million Americans and more than 35 million people worldwide. Experts predict that as the population ages, this number will triple by 2050, putting a huge strain on families as well as on the healthcare system and the economy.

Women are doubly affected by this disease for two reasons: First, more women than men have AD, in large part because women tend to live longer than men and the biggest risk factor for AD is increased age; and, second, women carry a heavy burden in terms of caring for ill and aging family members.

Some research suggests that not only are women more likely to get AD but they also survive longer after diagnosis and with higher levels of disability. And while it is obvious that there are biological differences between women and men, whether those differences put women at higher risk of disease, or affect how the disease progresses or responds to therapy, is not clear.

Estrogen is the most frequently cited physiological difference between women and men, but many other differences between the male and female brains may also play a role. For example, scientists have found both structural and genetic differences between men’s and women’s brains. And men and women also use different areas of their brains to accomplish certain tasks, such as retrieving an emotional memory.

The role of estrogen in AD has yielded some seemingly conflicting data, leaving many women confused about whether estrogen replacement therapy is safe. Estrogen is known to positively affect learning, memory, and mood and is thought to be neuroprotective, meaning that it protects the brain from harm. Because estrogen levels fall after menopause, it was thought that estrogen replacement therapy could protect against cognitive aging. But a very large study of women taking estrogen therapy, called the Women’s Health Initiative Memory Study, showed that in women over the age of 65 the treatment worsened rather than improved protection from cognitive decline. This led to a new idea called the critical period hypothesis, which holds that estrogen is protective in the brain only if given in midlife, close to the time when menopause begins. For now this is only a theory, but if ongoing research supports this idea, it may mean that hormone replacement therapy is safe during the early stages of menopause.

Is It Alzheimer’s Disease?

Memory loss is usually the first symptom of Alzheimer’s disease, but over time other symptoms such as personality changes and a decline in the ability to care for oneself may appear. In the early stages, it may be difficult to determine whether forgetfulness represents a typical age-related change or if there is a degenerative process affecting the brain. (See “10 Warning Signs of Alzheimer’s” sidebar on page XX). Moreover, in women the fall in estrogen at the time of menopause may also cause problems with memory, word finding, irritability, and mood swings, which may mimic the early symptoms of AD. If indeed a fall in estrogen is the cause of symptoms, it will likely respond to treatment.

Establishing a definitive diagnosis of AD, particularly in the early stages, is difficult, although new tests are being developed that may eventually provide a way for primary care providers to diagnose the disease. Currently, these tests are used primarily for research purposes, to learn more about the disease and to aid in the search for new treatments. Indeed, many investigators in the AD research community believe that we are on the verge of breakthroughs in diagnosis and treatment that may provide hope for people with AD and their families. For now, however, there are only a few symptomatic treatments available, and nothing that changes the course of the disease.

Women as Caregivers

Women are not only more likely to have AD but they also bear the brunt of caregiving for people with AD, and these caregivers experience high levels of stress and depression. Caregiving can also have a negative impact on a person’s job and finances. Fortunately, there are resources available to help caregivers cope with the challenges they face. The Alzheimer’s Association (www.alz.org) and the National Institute on Aging’s Alzheimer’s Disease Education and Referral Center (www.nia.nih.gov/Alzheimers) both provide information and help for families and caregivers struggling to cope with a loved one’s diagnosis of AD.

Reach Out for Help and Hope

For women with AD as well as for women caring for others with AD, one way to battle the sense of helplessness that can be so debilitating is to get involved with advocacy and research organizations that are working to raise awareness about AD and the need for more research and improved treatment options. For more information contact the Alzheimer’s Association.