Your Medical Destiny
Mining your family’s past for information can help safeguard your future health.
You’re sitting in a new doctor’s office, bending over a clipboard. On it is a list of ailments and conditions, from atrial fibrillation to yellow fever. “Does anyone in your family have a history of——?” the form asks. It’s tedious to fill out, and perhaps frustrating (what if you simply don’t know if your grandfather had anemia?) but it’s also a vital tool for your health. That history can help provide a road map of your possible medical future, and the steps you need to take to keep yourself hale and hearty longer.
Certain genetic variations can cause an increased likelihood of developing particular diseases. Says Dina Hennedy, D.O., a family physician at Family Practice of CentraState in Marlboro: “Knowing your family medical history gives insight into your own genetic risk factors. It provides information that allows clinicians effective risk stratification.” That means it can be used to accurately determine the correct level of care and monitoring you need. “It leads to earlier screenings, better strategies for prevention and/or focused monitoring for future office visits,” says the doctor. “Any family medical history patients provide is helpful information.”
Which medical conditions should raise red f lags if you see them in your family tree? Dr. Hennedy singles out four:
Breast cancer. Apart from skin cancers, this is the most common cancer in women in the U.S. If your mother or grandmothers had it, pay special attention. Mutations or variants in the two “breast cancer” genes, BRCA1 and BRCA2, are inherited from your parents and greatly increase your risk of developing the illness. “We look for a history of breast cancer in first- and second-degree relatives, as well as their age at diagnosis, to estimate lifetime risk,” says Dr. Hennedy.
A first-degree relative is a parent or full sibling; a second-degree relative is an aunt, uncle, grandparent or half-sibling. “If the estimated lifetime risk is 20 percent or greater, we consider that high risk and adjust screening recommendations,” the doctor explains. Annual breast-cancer screenings should begin no later than age 40 but, for high-risk individuals with a strong family history, the recommendation is “10 years prior to the youngest family member’s age of diagnosis, with earliest screening at 30,” says the doctor. She adds, “For patients who do fall into the high-risk category, there are genetic counselors who can test for genetic mutations,” including the BRCA gene mutations.
Colorectal cancer. This cancer also runs in families and can be caused by an inherited gene mutation, specifically in genes that help keep cell growth in check (such as the APC, or adenomatous polyposis coli gene) or repair DNA (for example, four genes known as MLH1, MSH2, MSH6 and PMS2). The term “Lynch syndrome” now describes what was formerly known as hereditary non-polyposis colorectal cancer: a defect in one of these cell-repairing genes that makes a malignancy more likely.
It’s recommended that routine screenings for colorectal cancer start at 45 for most patients but, says Dr. Hennedy, “individuals are considered to be at increased risk if there is a first-degree relative with history of colorectal cancer. For these patients, a colonoscopy is recommended every five years, starting at age 40, or 10 years prior to the age of earliest diagnosis in their family— whichever comes first.” As with the BRCA genes, genetic testing makes it possible to screen for Lynch syndrome, APC gene mutations and other common mutations that can increase your risk of colorectal cancer.
Cardiovascular disease. CVD is the leading cause of death in both the country and the world, and someone dies of it every 34 seconds, according to the Centers for Disease Control and Prevention. Though the lifestyle factors for developing it are well known (the doctor stresses the importance of a healthy diet, regular exercise and the avoidance of smoking), Dr. Hennedy says:
“Family history is an independent risk factor for CVD, with the risk increasing as the number of affected first-degree relatives increases and with earlier age of onset.” That means that talking to your relatives about when they were diagnosed is even more important in this case. “It can identify individuals who would benefit from earlier preventive measures,” says the doctor. This can range from lifestyle changes—a high enough genetic risk of CVD may make it reasonable for someone to completely abstain from alcohol, for instance—to prescription medicines, such as anticoagulants given to help prevent blood clots.
Type 2 diabetes. According to Dr. Hennedy, “Type 2 diabetes has a strong hereditary component associated with it, particularly if a parent or sibling is also diagnosed.” It’s also multifaceted; in the words of the American Diabetes Association, “You inherit a predisposition to the disease, then something in your environment triggers it.” Dr. Hennedy explains: “The interaction between genetics and environmental factors, such as obesity or physical inactivity, can increase the chances of developing diabetes.” If you have a sibling or parent who has been diagnosed, she recommends “regular office visits with routine lab monitoring, which are crucial in preventing type 2 diabetes, or identifying prediabetes earlier.” Knowing family risk factors and keeping up with that lab monitoring “allows for discussions regarding lifestyle modifications and treatment options,” she says—for example, a blood-pressure medication or a collaboration with a nutritionist on a healthy diet plan.
Sometimes talking about family medical history can be uncomfortable. Maybe your mother, for example, feels shame over being prediabetic and doesn’t want to discuss it with her kids. Tactful patient education can help. “We explain that family health history is a key factor in early detection for others,” says the doctor. “That will often motivate individuals to share with close family members.”
