For more than 35 years, researchers at Harvard School of Public Health have been regularly surveying hundreds of thousands of nurses throughout the United States for research that fundamentally changed our understanding of women’s health. Now they are looking to study the next generation of nurses, enrolling another 100,000 women, ages 20 and older.
The Nurses’ Health Study began in 1976, enrolling about 120,000 nurses ages 30 and up with the goal of studying breast cancer and the long-term effects of taking oral contraceptives. In 1989, another 116,000 women began filling out regular surveys about their lifestyles and medical histories.
The researchers chose nurses for two reasons, said Dr. Jorge Chavarro, assistant professor of nutrition and epidemiology and an investigator on the project. They knew the women would be committed to the project. And they knew that, for the most part, they could trust the nurses’ assessment of their own medical histories.
Ask a layperson if she has ever had a heart attack and she may say yes when she instead experienced atrial fibrillation, or an irregular heart beat.
“If a nurse tells you she had a heart attack she probably did indeed have a heart attack,” Chavarro said.
The results of the studies have been far-reaching, leading to a better understanding about cardiovascular risks in women, risk factors related to birth control, and the dangers of diets high in trans fat.
Just in recent years, study results have highlighted the possible role of aspirin in preventing cancer, found that light drinking raises a woman’s risk of breast cancer and that coffee consumption may lower risk of skin cancer, raised concern that women who work night shifts are more likely to develop diabetes, and outlined factors contributing to adult weight gain.
As the women in the first round of the study grow older, researchers are using their data to look at factors contributing to Alzheimer’s disease, other age-related illnesses, and healthy aging, Chavarro said.
The goal with the latest recruitment is to attract young women. The past two rounds began recruiting women at ages 30 and 25, Chavarro said. But researchers now know that women begin accumulating risk for breast cancer in their adolescence and early adulthood. This study will include survey questions about factors such as diet in those years.
“If you’re 21 and 22 years of age, it’s much easier for you to answer questions about your adolescence, which was only a few years ago, than when you’re 35 and 40,” Chavarro said.
Another goal is to make the study group more diverse, he said. Minorities made up only about 5 percent of women who have participated in the prior studies.
“That’s how nurses looked back then, but that is not how nurses look right now,” Chavarro said.
Recruitment for Nurses’ Health Study 3 started about a year ago. The researchers are relying heavily on professional groups, word of mouth among nurses, and online tools to attract people to the study. (They can be found on Twitter and Facebook.) So far, about 25,000 women have signed up, about 10 percent of whom are minorities.
The Nurses’ Health Study is women only. But Harvard has a “brother study” that follows men in health professions that will be recruiting in the coming years as well, Chavarro said.
Patti Eisenberg, of Malibu, Calif., has been enrolled in the study for decades. Now retired, she was an advanced practice nurse for more than 30 years. Eisenberg said it has been gratifying to see how the study has advanced women’s health.
“The reason most of us go into nursing is that we want to make a difference,” she said. “To me, this was another way we could do it, with our bodies this time and not just our minds.”
Eisenberg said she has filled out regular surveys and, when the researchers have requested it, sent blood or urine samples.
“That’s kind of effortless,” she said. “But the information that they’re getting from it is so phenomenal.”
Chavarro said he is particularly interested in exploring issues around fertility and complications in pregnancy. The surveys also will delve into workplace risk factors for the nurses, including heavy lifting and exposure to anti-cancer drugs or anesthesia.