CHAPTER 6

MEDICAL HISTORY AND LABORATORY TESTS

AT THE RISK OF BELABORING THE POINT, I want to emphasize that taking care of yourself is of the utmost importance, no matter what your DNA is or isn’t. In this regard, there are ways that scientists can help, and there are ways that doctors can help—but if you’re like most any woman I’ve ever met, you know that we also need to learn to help ourselves. Where cognitive health is concerned, many of our worst worries can be avoided by showing ourselves proper TLC.

Managing our medical status is crucial to this aim. In fact, some medical conditions can increase the risk of Alzheimer’s or worsen its symptoms. These are chiefly heart disease, diabetes, obesity, and depression, which all can in and of themselves affect cognitive performance, dampening our mental acuity and clouding our memories.

Further, more than forty medical conditions have been identified that can cause or mimic the symptoms of dementia, thereby misleading people into thinking they are slipping into some form of mind-robbing disease. Fortunately, most of these conditions are treatable and often completely reversible. Two common examples are vitamin B12 deficiency and an underactive thyroid (hypothyroidism). Our minds can be dramatically affected by these and other influences, such as infection, inflammation, and metal poisoning, to name but a few—which all are within our control to address. Getting the right diagnosis is crucial because, in many cases, symptoms subside when the underlying problem is treated. So it is imperative to recognize these manageable conditions and deal with them pronto.

Regular medical checkups combined with the recommendations included in part 3 of this book, such as a healthy diet, moderating alcohol consumption, avoiding cigarettes, keeping stress and inflammation at bay, and consistently exercising, among others, can not only improve but also reverse most if not all of these conditions. Some of these shifts you can actually attend to yourself, while others will require a doctor’s help. But if you really let that fact sink in, many of you may be taking a huge sigh of relief about now.

These next chapters focus on developing a comprehensive risk management plan that starts with compiling a clinical and medical history. This includes your current and past medical problems and concerns, including any medications, your family’s medical history, your current lifestyle choices, and your exposure to environmental hazards. This information will provide the framework for your specialized treatment plan by highlighting any specific areas of concern. We will start by outlining what a typical clinical evaluation for brain health involves, including select tests that you can easily get done with your doctor’s assistance. In the next chapter, we will use these test results to further refine your personalized risk assessment.

For all tests, reference values are included in table 1.

TABLE 1. KEY MEDICAL AND LAB TESTS FOR ALZHEIMER’S PREVENTION AND MANAGEMENT

INDEX

TEST

REFERENCE VALUES

Optimal

Borderline

High risk

Central body fat

Body mass index (BMI)

18.5–25

25–30

>30

Waist-to-height ratio

0.42–0.48

0.49–0.5

Over 0.5

Hypertension (high blood pressure)

Blood pressure (mmHg)

<120/80

120/80–140/90

140/90

Metabolic markers

Fasting blood glucose (mg/dL)

70–99

100–125

<70 or >125

Fasting blood insulin (mcU/ml)

<5

5–15

>15

Hemoglobin A1c (HgA1c, %)

4–5.7%

5.7–6.4%

>6.4%

Lipid markers

Total cholesterol (mg/dL)

<200

200–240

>240

HDL cholesterol (mg/dL)

>60

50–60

<50

LDL cholesterol (mg/dL)

<100

100–160

>160

Triglycerides (mg/dL)

<150

150–200

>200

Lipoprotein A (Lp[a], mg/dL)

<30

30–50

>50

Thyroid function

TSH (µIU/mL)

<0.27

0.27–4.2

>4.2

Homocysteine

Homocysteine (mcmol/L)

<10

10–14

>14

Nutrients

Vitamin B12 (ng/L)

190–900

150–190

<150

Folate (ng/L)

5.8–32.8

3–5.8

<3

Omega-3 DHA (mcg/mL)

>100

60–100

<60

Omega-3 index

>8%

4–8%

<4%

Inflammation

Hs-CRP (mg/mL)

<1

1–3

>3

Hormones

Follicular phase

Ovulation

Post-menopause

Estradiol (pg/mL)

12.4–233

41–398

<138

Progesterone (ng/mL)

0.06–0.89

0.12–12

<0.05–0.13

FSH (mcIU/mL)

2.4–12.6

14–95.6

7.7–58.5

LH (mcIU/mL)

3.5–12.5

4.7–21.5

25.8–134.8

6–8 a.m.

4 p.m.

Bedtime

Cortisol (mc/dL)

10–20

3–10

<5

LET’S GET PHYSICAL

This first step involves assessing your weight, height, waist circumference, and blood pressure. These parameters will help clarify if you are at risk for cardiovascular disease, obesity, or diabetes.

Check Your BMI

Being overweight or obese can increase your risk for heart disease and diabetes, which in turn increase your risk of Alzheimer’s. Incidentally, increasing weight is also one of the surest ways to get hot flashes. In a meta-analysis of over 4,000 women, obese women reported experiencing almost 80 percent more hot flashes than their slimmer peers. Just being overweight is enough for the incidence of menopausal symptoms to increase by 13 percent.

Your body mass index (BMI) can give you an idea of what a healthy weight range means for you, and can help you set a weight-loss goal if you need to lose weight. Keep in mind that men and women have a different target BMI, which further differs by age. Generally, an age- and gender-adjusted BMI between 25 and 30 is classified as overweight, and a BMI over 30 is considered obese. This online BMI calculator from the Centers for Disease Control and Prevention is accurate and easy to use: www.cdc.gov/healthyweight/assessing/bmi/adult_bmi/english_bmi_calculator/bmi_calculator.html.

Find Your Waist-to-Height Ratio

The waist-to-hip ratio is the most commonly used indicator of central body fat, aka belly fat, a marker of heart disease risk at all ages, but particularly important around menopause. To calculate it, measure yourself around the smallest part of your waist, being careful to not hold in your stomach! Then take a measurement at the widest part of your hips. Divide your waist measurement by your hip measurement. For example, a person with a thirty-inch waist and thirty-eight-inch hips has a waist-hip ratio of 30/38 = 0.78. In general, for women, the ratio should be no greater than 0.8; the number for men is 1.0. If you are above that, it means that you are at risk. However, since women’s hips are classically wider than their waists, this test can lead to underestimating adipose fat and therefore risk of heart disease in women.

A more accurate measurement is your waist-to-height ratio, which is calculated by dividing your waist size by your height. If your waist measurement is less than half your height, you’re not likely to be at risk. Specifically, for women, a waist-to-height ratio between 0.42 and 0.48 is considered healthy. These rules bend somewhat after menopause, as some weight gain around the waist is normal. But as a rule of thumb, a five-foot-four (sixty-four-inch) woman should aim to keep her waist less than thirty-two inches, while a five-foot-nine (sixty-nine-inch) woman should ideally keep her waist measurement under 34.5 inches.

Measure Your Blood Pressure

High blood pressure (hypertension) is a well-known risk factor for heart disease and stroke. It can quietly damage your body for years before symptoms develop. If left uncontrolled, you may wind up with a disability, a poor quality of life, or even a fatal heart attack. What is perhaps less known is that hypertension is also a common cause of vaginal dryness and reduced sexual desire in women. From a neurological perspective, effective management of hypertension, especially in midlife, is important to also reduce the risk of future cognitive declines. If your blood pressure is chronically high, lowering it can lower the impact of mild cognitive impairment, which is the next best thing in the study of dementia prevention. Additionally, some studies suggest that APOE-4 carriers might particularly benefit from blood pressure management.

There is less evidence for an association between low blood pressure (hypotension) and an increased risk of heart disease or dementia. Nonetheless, low blood pressure can cause dizziness, weakness, fainting, and a risk of injury from falls, which needs to be addressed, too.

Treatment and lifestyle changes can help control your blood pressure to reduce your risk of life-threatening complications. So have your doctor measure your blood pressure at regular intervals, ideally every six months to a year, especially if you are post-menopausal. Blood pressure readings are made up of two numbers, for example, 140/90. The first number is your systolic blood pressure, or the highest pressure reached when your heart is busy pushing the blood throughout your body. The second number is your diastolic blood pressure, which is the level of pressure maintained as your heart relaxes between beats. Here are some things to look out for:

LABORATORY TESTS

In the clinical workup of dementia, but also for dementia prevention, blood and urine samples are routinely collected to rule out infections and to check how organs, such as the liver or kidneys, are functioning. Always ask your doctor to make sure you don’t suffer from infections, especially UTIs, which are frequent in women. Silent UTIs in particular are tricky to spot because they don’t trigger obvious symptoms like burning or itching, but can seriously cloud your head.

In more specialized centers like ours, several additional lab tests are performed to measure lipid and metabolic markers known to impact cognitive function (see table 1). These tests can help determine if you have insulin resistance or diabetes, high cholesterol or high triglycerides, or nutrient deficiencies, which all can both mimic the symptoms of dementia and increase its risk. Lab tests can also help assess your hormonal levels. As much as you can, always know your numbers!

Get a Fasting Glucose and Insulin Test

These tests help you find out if you have diabetes or could be at risk for it:

Women with the APOE-4 gene need to pay extra attention to these metabolic markers. There is evidence that, especially as they go through menopause, APOE-4 carriers with insulin resistance tend to experience more severe memory decline as compared with those with a regular metabolism.

Get Your Fats Checked

If you have an abnormal amount of fat in your blood (dyslipidemia), you may be at risk for both cardiovascular disease and insulin resistance. This is especially the case if you have high total cholesterol (over 240 mg/dL), particularly low HDL cholesterol (below 50 mg/dL for women or 40 mg/dL for men), high LDL cholesterol (over 160 mg/dL), and/or high triglycerides (over 200 mg/dL).

Additionally, some studies have indicated that a type of cholesterol called Lipoprotein(a), or Lp(a), may do a better job at predicting cardiovascular risk for women. This is particularly true for those who have a past history of heart disease, or for women with a family history of early-onset heart disease or sudden death in the family. The research is still ongoing, but it looks like women who would be considered at low risk for heart disease based on standard examinations may instead harbor higher risk related to elevated levels of Lp(a). For example, if your total cholesterol levels are normal but your Lp(a) is high, your risk is also high.

APOE-4 carriers should pay extra attention to their lipid levels too. Besides being a risk factor for Alzheimer’s, the APOE-4 variant increases risk of heart disease, likely due to its negative effects on raising LDL cholesterol. Higher circulating LDL can lead to an increased formation of plaques in the vascular system and reduced circulation, effectively delivering a one-two punch to cholesterol and blood flow at the same time.

Generally, patients with out-of-range values are advised to lower their lipid level, especially LDL cholesterol. This can be sometimes achieved by means of drugs such as statins, but also by following the drug-free lifestyle recommendations described in part 3.

Check Your Thyroid

Thyroid disease, especially having a sluggish thyroid (hypothyroidism) can cause symptoms similar to those of menopause, as well as high cholesterol, weight gain, and fatigue. It is also a cause of reversible cognitive disturbances.

The thyroid-stimulating hormone (TSH) has long been part of the screening laboratory test for dementia. Optimal TSH levels range between 0.27 and 4.2 mcIU/mL. Levels below 0.27 and above 4.2 may be indicative of thyroid dysfunction. Other tests measuring available thyroid hormones circulating in the bloodstream (Free T4, Free T3) are also helpful indicators of thyroid function. Your doctor may also want to test for TPO and TGB antibodies to rule out autoimmune conditions that attack the thyroid, such as Hashimoto’s disease and Graves’ disease. In case of a positive test, speak to your doctor about available treatments, and also make sure that you follow the hormone-balancing recommendations outlined in the next chapters.

Homocysteine, a Marker of Vascular Risk

A high level of homocysteine is not only a risk factor for heart disease, stroke, and hardening of the arteries, but for dementia as well. Homocysteine levels above 14 micromol/liter are considered high. However, new research shows that the risk of developing dementia is nearly doubled in people with homocysteine levels at or above 13. This indicates that our brains are more sensitive to this substance than previously imagined. Optimal homocysteine levels are below 10. If your level is higher, make sure you work with your doctor to lower it.

The good news is that since homocysteine levels are in part regulated by specific B vitamins, high homocysteine is reversible by eating a healthy diet rich in these vitamins, or by taking specific supplements, as described in chapter 11.

Don’t Skip Your Nutrients, Especially the B Vitamins and Omega-3s

Deficiencies of some B vitamins, especially B6, B12, and folate (B9), can lead to problems with brain function, the nervous system, and other aspects of your health. Besides altering homocysteine levels, low B-vitamin levels can provoke cognitive decline and even mimic the symptoms of dementia. For example, low levels of B12 can cause pernicious anemia, a condition that can lead to fatigue, fuzzy thinking, confusion, moodiness, and slowness. Researchers believe that up to 15 percent of people in the United States have some vitamin B12 deficiency. It’s therefore important to check your blood levels if there are any signs that they may be low. Sometimes, a test that measures MMA (methylmalonic acid) is used as a follow-up to help diagnose an early or mild deficiency in case of a B12 test result that is at the lower end of the normal range.

Omega-3 fatty acids work to protect your brain cells from the wear and tear that naturally occurs with aging, while also providing support for the cardiovascular system. Adequate omega-3 levels have been associated with reduced brain shrinkage, preserved memory, and a reduced risk of dementia in late life. Not all doctors check omega-3 levels, but we believe this measurement to be helpful for Alzheimer’s prevention.

The so-called omega-3 index is another important measurement. A higher omega-3 index indicates that you consume a balanced amount of omega-3s and omega-6s. This is favorably associated with a reduced risk of many chronic diseases, especially cardiovascular disease. Because Americans as a rule consume far too few omega-3s from fish or fish oil, it’s no surprise that an estimated 95 percent (with the exception of folks from Alaska) have a low omega-3 index, putting them in the high-risk category. In general, in countries with high fish consumption, such as Asia and Northern Europe, this is less of a problem.

Most people who eat a balanced diet should have adequate B vitamins and omega-3s. But there are exceptions. After age fifty, our metabolism naturally slows down and absorption of vitamin B12 may decrease as a result. Further, gastritis, Crohn’s disease, celiac disease, and immune disorders such as lupus may cause your B12 levels to go down. Several types of medication might also affect your B12, especially drugs to help treat acid reflux, peptic ulcers, and indigestion, like antacids (e.g., Tums) and proton-pump inhibitors (e.g., Prilosec, Prevacid), as well as Metformin, a drug for diabetes. Vegan and strict vegetarian diets can also lead to deficiencies in both B12 and omega-3s. Additionally, women are particularly at risk of folate deficiency during pregnancy, as a growing baby absorbs lots of folate from its mother. Birth control pills are also known to deplete your B vitamins, and so is heavy drinking.

In all of these cases, talk to your doctor about having your vitamin B and omega-3 status checked. In chapter 11, we will discuss whether nutritional supplementation may be helpful to you, and under what circumstances.

C-Reactive Protein: A Marker of Inflammation

There are several parameters we can measure in blood to detect the presence of inflammation. One of the most reliable tests is known as the CRP test. CRP, or C-reactive protein, is one of the chemicals produced by the immune system to fight harmful substances in the body, and it’s also one of the chemicals that leads to inflammation. The CRP test measures the amount of this protein in the blood. Although it doesn’t tell where the inflammation is or what’s causing it, this test is a good way to determine if something is off. In particular, high-sensitivity CRP (hs-CRP) can detect insidious low-grade inflammation, and is often used to assess risk of heart disease as well.

High Cortisol: Too Much Stress

You probably don’t need a blood test to find out if you’re under stress. However, stress can be insidious, especially if you’ve been suffering from it for a long period of time, in which case an objective measure might help motivate you to take the problem seriously. The Stress Screener in chapter 7 is a good starting point to determine if you need to seek your doctor’s guidance. If so, it might be helpful to also have your cortisol (e.g., the main stress hormone) checked.

Cortisol can be measured via your blood, urine, and saliva. The blood test is far more accurate, and is typically done twice in the same day, once in the morning and again later in the afternoon. That’s because cortisol levels change a lot in the course of a day. High cortisol levels can also indicate the presence of infections or Cushing’s syndrome, a medical condition characterized by weight gain, bruising, thinning of the skin, and even cessation of menstrual periods. That said, if you feel under stress, as so many of us are, you may as well skip the blood test and just take action. Chapter 13 provides several stress-busting recommendations to get you started.

Your Sex Hormones: To Check or Not to Check

When a woman suspects she’s in perimenopause, it’s an excellent time to have a complete medical examination by a qualified health professional, either an ob-gyn or an endocrinologist (see appendix A for how to find one). The diagnosis of perimenopause can usually be made by reviewing a woman’s medical history, her menstrual history, and any signs or symptoms.

Blood tests typically aren’t needed to diagnose menopause. But under certain circumstances, your doctor may recommend tests to check your levels of estradiol, FSH, and LH. Your estradiol levels decrease, while FSH and LH levels increase as menopause occurs.

The best way to measure your blood hormone levels is to have your doctor do it. Over-the-counter home tests to check FSH levels in the urine and saliva are available but unfortunately they’re not particularly reliable.

However, not even the most accurate blood tests can tell you for sure whether you’re in menopause. For example, since FSH levels rise and fall during the course of your menstrual cycle, they can be low one day and then quite high the next. More important, you can be in perimenopause even if your FSH levels are low. The same goes for estradiol levels, which can fluctuate widely during each month. Also, if you are taking birth control pills or have an IUD, or if you’re taking breast cancer medications, the test results may not give you an accurate picture. If you are concerned about your menopausal status, I recommend that you fill out the Menopause Screener in chapter 7 and seek your doctor’s guidance.

COGNITIVE TESTING

Mental cognitive status tests are a key step to evaluating memory, thinking, and problem-solving abilities in an objective way. Some tests are brief, while others can be more complex and time-intensive. More comprehensive cognitive tests are often given by a neuropsychologist, and only specialized centers and licensed clinicians have access to these rigorous tests. Online cognitive testing and brain teasers are widely available, but are currently not recommended for diagnostic purposes. We’ll look into this in more detail later.

For now, I want to draw your attention to an important fact. Men and women differ in the way in which they experience cognitive changes. In fact, the early signs of cognitive decline, and even of Alzheimer’s, are easier to spot in men. This is due to the fact that, throughout our adult life, women outperform men in a variety of cognitive tasks. This is especially true of verbal memory—the ability to recall words and stories, and to access language verbatim. Studies that compared memory performance between men and women at different stages of life showed that the only period when women start displaying measurable decline in memory performance on cognitive testing is after menopause. But in spite of this, many post-menopausal women continue to have an edge over their male counterparts in midlife as well as in old age, and sometimes even into the early stages of Alzheimer’s.

While this is certainly good news, there is one downside to this advantage. The thing is, verbal and associative aspects of memory are one of the major cognitive measures used to diagnose a memory disorder, and one of the primary reasons people seek medical help. While to some extent we are all resigned to the idea that we may lose our keys or misplace our belongings, we are much less tolerant of how failing to come up with words or remember conversations can impact our social and work lives. However, since women tend to be better at this function than men and reference values are not always gender specific, this may hinder a doctor’s ability to recognize and diagnose Alzheimer’s. Women may also wait longer to go see a doctor, with the result that by the time they are finally diagnosed, the disease has had a chance to grow more severe, while male patients are diagnosed sooner. We are left to wonder how many women remain undiagnosed until the deficits are so severe that treatments no longer have a chance to work.

Hopefully, soon enough we’ll have tests that work for women. In the meantime, pretty much everyone agrees that looking at a patient’s brain is much more informative and accurate than cognitive testing alone.

BRAIN IMAGING

Our brains possess something akin to a fingerprint. While the architecture of the brain—with its various partitions into lobes, functional areas, and specific structures—may be roughly the same in all of us, there are significant variations when it comes to the size, shape, activity, and molecular composition of our brains. This tremendous variability is never more evident than when viewing brain scans.

I have been doing brain imaging for over fifteen years, inspecting and quantifying thousands of scans—and not a single day goes by when I do not stand in awe of the uniqueness the scans reveal, each patient’s brain different and distinct from the next. The brain’s individuality not only is based on our unique genetic makeup but is also shaped, molded, and “written upon” by our backgrounds, education, and experiences. Add to that the many foods you’ve been exposed to, your cultural environments, all the places you’ve explored, and all the joys and sorrows of your life, and it only makes sense that no two brains could ever be alike. In my opinion, brain scans are absolutely essential to understanding a person’s brain and any individual risk factors that may affect cognitive function. And let’s not forget that a brain scan can detect Alzheimer’s many years before symptoms emerge.

Several types of brain scans are widely used in clinical practice and research. A typical clinical examination starts with computerized tomography (CT) or magnetic resonance imaging (MRI), both of which take pictures of the inside of your brain to reveal its structure and anatomy. These scans are particularly helpful to rule out a variety of conditions that can cause cognitive changes very similar to those observed in dementia patients. Four of these conditions in particular pose greater risks to women: brain tumors, aneurysms, white matter disease, and atrophy.

According to the American Brain Tumor Association, about 80,000 adults and children are diagnosed with a primary brain tumor each year. The chance of developing a brain tumor is very small, with a lifetime risk of 1 percent or less. However, there is variability in the risk of developing a brain tumor for males and females. In particular, meningioma, the most common primary brain tumor, is more common in women than in men, in part because of its interactions with our sex hormones. Most meningiomas are slow-growing and benign, but even those can sometimes cause cognitive issues that can be mistaken for Alzheimer’s. Fortunately, meningiomas can usually be managed and sometimes removed without risk of severe damage to the brain, especially if caught soon enough—which would be impossible to do without a brain scan.

Aneurysms are another condition to watch out for. Think of an aneurysm as beginning with a weak spot in the wall of a blood vessel inside the brain. With continued flow of blood to the vessel, the spot gets worn out and starts bulging, almost like a small bubble. While many aneurysms don’t cause symptoms, in some cases, they can grow big, leak, or explode. Bleeding in the brain, known as hemorrhagic stroke, is very serious and requires urgent medical care. Among all causes of stroke, ruptured brain aneurysms occur twice as often in women as in men, especially between fifty and fifty-nine years of age, often in correlation with the fall in estrogen levels that comes during menopause. In terms of prevention, brains scans make it possible to detect these risks, and the positive medical and lifestyle changes described in part 3 can significantly reduce the odds of a brain aneurysm leaking or popping and, more generally, of stroke.

Now on to white matter disease. This condition results from the wearing away of brain tissue in the largest and deepest part of the brain: the white matter. This tissue contains millions of nerve fibers that connect different parts of the brain and spinal cord and that signal nerve cells to talk to one another. A fatty material called myelin protects the fibers and gives white matter its milky color. Your white matter helps you think fast and walk straight, and keeps you from falling. When it becomes diseased, the myelin breaks down, impairing nerve communication. White matter disease has been associated with increased odds of negative outcomes, especially for women, once again in particular those undergoing menopause. However, there are ways to prevent and even reverse this condition, chiefly the heart-healthy practices we’ll review in the next chapters.

Finally, let’s talk about brain atrophy. MRI scans are key to determining if your brain is aging well. Over time, certain parts of the brain may shrink (“atrophy”), especially those important for learning, memory, and planning, as well as other complex mental activities. That’s what we’re on the lookout for when inspecting an MRI scan of an aging person. Is the brain as large and full as it should be relative to its peers? Are there any signs of atrophy? Some scans can show signs of cortical thinning or ventricular enlargement, which occur when the brain is losing tissues. Brain shrinkage could be an early sign of Alzheimer’s, or an indication that your brain is aging faster than desirable, the latter being a common finding in some women in menopause. As we now know, age-related neuronal loss can be due to a number of medical and lifestyle factors we can not only modify but even completely eliminate.

Personally, I am a big fan of another brain imaging technique, called positron emission tomography, or PET. PET offers the unique ability to look at the brain’s energy activity, as we saw in chapter 1, as well as to examine a variety of other parameters like a brain’s neurotransmitter portfolio, uptake of essential fatty acids, inflammation, and a multitude of important chemicals needed for brain health. But most important, PET is currently the only technique that allows us to determine if a patient is suffering from Alzheimer’s by detecting the presence of another major brain problem: amyloid plaques.

The ability to spot Alzheimer’s hallmark signs in the brain is crucial for clinical purposes, especially for patients with an uncertain diagnosis. “Uncertain diagnosis” means that a patient is showing symptoms that could be caused by Alzheimer’s as well as by another form of dementia, and the doctor is not sure which one is which. For example, patients with a diagnosis of Alzheimer’s who show speech difficulties (aphasia) or disinhibition—typical symptoms of another condition called frontotemporal dementia (FTD)—could have either Alzheimer’s or FTD, as these conditions possess some common features. Does the patient really have Alzheimer’s, or is it FTD instead? Since Alzheimer’s plaques are not found in the other form of dementia, a positive PET scan revealing them would confirm an Alzheimer’s diagnosis. On the other hand, a negative PET scan showing no Alzheimer’s plaques would effectively rule out Alzheimer’s as the cause of the dementia symptoms present.

Believe it or not, almost 20 percent of patients with a diagnosis of Alzheimer’s turn out not to have Alzheimer’s, as determined via their PET scans. Use of PET scans can lead to a change in diagnosis in as many as 69 percent of cases—and a change in patient treatment plans in about 25 percent of cases. Clearly, this information can prove extremely valuable.

PET is also the only technique able to detect early Alzheimer’s brain changes in people at risk for the disease. PET scans are particularly good at detecting the presence of Alzheimer’s plaques decades before patients manifest any actual symptoms of the disease. These so-called predictive scans are currently not FDA-approved, which means that you can’t simply ask your doctor to prescribe one. The only way to get these scans is by participating in research studies like ours, or in clinical trials. Participating in brain-imaging research is a great opportunity to receive a top-notch brain health evaluation, establish a solid baseline to use for comparison with later assessments, and obtain invaluable information that you wouldn’t otherwise have access to. For example, finding out that you have (or don’t have) a brain tumor, aneurysm, or other life-threatening brain condition is frankly quite priceless. If you are showing signs of cognitive impairment, or are at genetic risk for Alzheimer’s (as described in chapter 6), clinical trials are also particularly attractive because in this case you can kill two birds with one stone: you have access to both the information provided by the PET scan and a treatment that might turn out to be successful. Plus, you will also be offered counseling, which is, of course, crucial. If participating in a clinical trial is of interest to you, a list of ongoing studies is included in appendix A. Just keep in mind that, for now, most clinical trials are restricted to people age sixty or older.

I am a firm believer in the value of brain imaging for disease prevention. Even though these techniques are currently available at only a few specialized clinics and research centers, it is my hope that we may soon make them much more accessible. With regard to women’s health, I look forward to the day when we will routinely peek inside a woman’s head and use her brain as our guide to providing the best recommendations specific to optimizing her health. Much in the same way a current female’s middle-age health-care routine includes mammograms, a more evolved women’s health-care system will demand careful attention with respect to brain aging, a full focus on the function of hormones in protecting it, and precision strategies to prevent Alzheimer’s from becoming a woman’s unnecessary destiny.

In the meantime, addressing the risk factors we can detect, and reacting with our current research’s know-how, are unquestionably the best strategies we have today. It is my mission to ensure that every one of us receives the support her brain deserves to function to its maximum, age gracefully, and make the all-too-frequent occurrences of dementia a thing of the past.