In the Family—But Not Hereditary Calculate your risk of five prevalent diseases (August/ September 2005) More health stories

Danilo Figueredo has his father's hands, with long slender fingers like a pianist, and his mother's narrow somewhat Asian eyes—which earned him the childhood nickname El Chinito. He hopes he didn't also inherit their propensity for heart disease. Figueredo's father was diagnosed with heart disease in his 50s and died of a heart attack at 62. His mother developed an arrhythmia—an irregular heartbeat—last year, at age 79.

"I was aware Dad had high blood pressure and [had died of] a heart attack," the 56-year-old Cuban American says. "I know that I have high blood pressure, but I didn't necessarily connect the dots."

It was only when he investigated his family's health history that he began seeing patterns. Knowing what illnesses your parents and grandparents have or had can help you determine your risk of developing certain chronic conditions such as diabetes, heart disease, and some cancers, according to experts. "Even if you're healthy now, having those kinds of diseases in your family is indicative that you're at risk," says Dr. Rodolfo Valdez, a Venezuela-born epidemiologist at the Centers for Disease Control and Prevention (CDC) who oversees the CDC's Family Health History Public Health Initiative.

"Some people say they don't want to know, that it's their destiny, but with many diseases there are things that can be done."

Genes or the Environment?
Miguel Ramírez—who asked that his real name not be used for reasons of privacy—remembers his dad in Colombia as a health-conscious man who ate plenty of fruits and vegetables. "I remember he liked to boil water to wash apples and oranges," he says. Even so, his father died of stomach cancer. "When you have it in the genes, you have it," the son says. "No matter all the precautions he took, he had cancer and died from it."

But was it genetic? And is Ramírez, 55, at risk? The interplay of genetic and environmental factors in disease is complex and not completely understood, experts say, especially because genes and culture are passed down through entire ethnic groups, not just families. Diabetes, for example, can have genetic and environmental causes. "Several different regions of the human genome have been associated with susceptibility to type 2 diabetes, and these may differ across populations," notes a study by the National Alliance for Hispanic Health and the National Pharmaceutical Council. "Mexican Americans appear to carry susceptibility genes for diabetes on one chromosome."

At the same time, Hispanic households in general have diets overly rich in carbohydrates and deficient in fiber, a contributing factor to type 2 diabetes, health care experts say.

Be a Medical Investigator
While doctors can tell patients to eat right, exercise, and stop smoking, Valdez would like physicians also to ask patients to collect their family's health history. It's information that patients seem eager to share. The 2004 HealthStyles Survey, licensed by the CDC, found that 96 percent of Americans believe knowing their family's medical history is important to their health, but only 30 percent—and 24 percent of Hispanics—said they had tried to collect information themselves.

"A good family history should have three generations going back to grandparents," Valdez says. "Look for a clustering of the disease in your family and patterns of inheritance. If the disease shows in one sex and not the other, it may be what is termed a 'sex-linked disease.' If it tends to skip a generation or if it doesn't skip a generation, those are patterns you should also look for. A genetic counselor could recognize these patterns easily."

It helps to lay it out visually. The CDC helped create My Family Health Portrait, a web-based tool that asks questions about relatives' diseases and produces a chart that makes it easier to spot clustering and patterns. Seeing those patterns is the first step. Understanding what they mean is the next.

What were the patterns of heart disease in Figueredo's grandparents? What difference does it make that Ramírez's father was diagnosed with stomach cancer when he was 69 years old, rather than at a younger age? At AARP Segunda Juventud's request, both men answered the questions in My Family Health Portrait and took the results to Dr. Jennifer Ibrahim, a clinical geneticist at St. Joseph's Regional Medical Center in Paterson, New Jersey.

Know the Risks and Take Action
Medical geneticists have begun to understand how genes carry chronic diseases from parent to child—perhaps silently at first, only to explode later. Technicians examine a patient's genetic material, but most people have a less expensive option: geneticists say they can assess risk by studying family health histories.

"We discuss family history with everyone who comes in, then we present options for testing," Ibrahim says. "Among people who are truly at high risk, particularly for cancer, about 75 percent opt for testing if they have insurance. But we see many individuals concerned about their family history...and we're able to assure them their risk isn't high enough to make the testing particularly useful." Instead, she may emphasize lifestyle changes or more than the standard medical vigilance.

Medical Mysteries Solved
After studying Figueredo's and Ramírez's family histories, Ibrahim says that both men are at higher risk than average for certain inherited diseases. For Ramírez, the major risk is for stomach cancer. When he began researching his family health history after his dad died of the disease, he learned—much to his surprise and dismay—that so had his dad's mother.

"It was a wake-up call," Ramírez says. When his father died, his mother told him to see a doctor because cancer ran in the family. "But I didn't pay attention," he says.

Ibrahim says that despite Ramírez's family history putting him at a higher risk than the general population for the disease, his risk is lower than it could have been. Both of his relatives were in their 60s when diagnosed. Had they been younger than 50, she says, Ramírez's risk would have more significantly increased. So even with stomach cancer in his family, Ramírez didn't need a colonoscopy at an age younger than 50. Ibrahim does suggest that when Ramírez has his colonoscopy, his doctors also examine his esophagus, stomach, and small intestine.

Danilo Figueredo's family health history, meanwhile, shows two areas of concern: heart disease and colon cancer. Only one relative, his paternal grandmother, had colon cancer. But she was diagnosed when she was in her 40s. That means Figueredo should have started having colonoscopies in his 30s. The rule of thumb, Ibrahim says, is to subtract 10 years from the relative's age at diagnosis. Figueredo also found widespread heart disease in his family. In addition, says Ibrahim, when it comes to heart disease, "There are obvious environmental factors. Someone with [Figueredo's] family history needs to address the genetic and the environmental."

In Figueredo's case, a culprit was poor eating habits. Ibrahim's advice: eat better and have his cholesterol checked regularly. Figueredo says he already eats healthier than his parents did. Now that he's connected the dots in his family's health history, he plans to watch his diet even more.

Most people never need genetic counseling, which can be expensive; check with your physician.