Dr. Elizabeth Barrett-Connor, who founded and led a 47-year-long study that identified sex differences in the risk factors for major diseases of aging, died on June 9 at her home in the La Jolla section of San Diego. She was 84.
The cause was cerebral small vessel disease, her daughter, Caroline Connor, said.
Dr. Barrett-Connor’s project was called the Rancho Bernardo Study of Healthy Aging, named for the San Diego suburb where its more than 6,000 participants had originally lived. It was begun in the early 1970s as part of a dozen group studies on preventing heart disease.
The study led to insights into the biology of diabetes, cardiovascular disease, bone health and menopause.
Dr. Barrett-Connor, then an associate professor at the University of California, San Diego, was the only one who kept the study going beyond its initial funding — for decades. It was testament to her persistence and ability to get things done on a shoestring, said a former colleague, Cedric Garland, a professor emeritus at the university.
Dr. Barrett-Connor insisted from the beginning that the research on aging include both male and female subjects. That method, unusual at the time, is now considered essential to disease research.
“It took someone to decide to do it,” said Gail Laughlin, an associate professor of epidemiology at San Diego. “I would consider one of her major contributions was her focus on sex differences.”
The study, which is continuing, has led to more than 450 scientific papers. It “went way beyond what we had before she started in the field,” Dr. Garland said. Dr. Barrett-Connor co-wrote more than 1,000 scientific publications herself.
She was among the first to show that diabetes removes the usual advantage that women have in avoiding heart disease; that increasing potassium in the diet may protect against stroke; and that drinking lots of caffeinated coffee over a lifetime can lead to low bone mineral density in women who do not also drink milk daily.
“She was a seminal thinker in epidemiology,” Dr. Laughlin said. Trained as an infectious disease specialist, Dr. Barrett-Connor won several major awards in epidemiology, although she never studied the subject.
She was also an entertaining speaker who could pack a room with scientists, Dr. Laughlin said, and a committed mentor.
One former student, Kay-Tee Khaw, a professor at the University of Cambridge, wrote in a recent tribute to Dr. Barrett-Connor, “So much of what she pioneered is now so well established in mainstream epidemiologic research that it may be difficult to realize how groundbreaking her approach was at the time.”
In conducting long-running studies using multiple individuals, Dr. Barrett-Connor was one of the first researchers to recognize the importance of accounting for lifestyle factors, like diet and physical activity, and social factors, like education. She also sought to include blood samples that would reveal sex hormones, thyroid function and metabolism, Dr. Khaw wrote.
Dr. Barrett-Connor was a believer in the scientific method. “The only reason to have a hypothesis was to try to disprove it,” she used to say, according to Dr. Laughlin. “If you couldn’t disprove it, you might be right — not guaranteed to be right, but you might be right.”
Elizabeth Louise Barrett was born on April 8, 1935, in Evanston, Ill., the only child of Willard and Florence (Hershey) Barrett. Her father was a chemist who worked for ammunition companies during World War II, requiring the family to move around the country for most of her childhood. They settled in Lee, Mass., when Elizabeth was a young teenager, her daughter said.
Dr. Barrett-Connor attended Mount Holyoke College in Massachusetts, where she majored in zoology. She graduated in 1956.
According to family lore, she was heading to the train station to take a nursing school entrance exam when she bumped into a friend. “You’d make a terrible nurse,” the friend was said to have told her. “You can’t take orders from anybody.” Acknowledging the truth of her friend’s comment, Dr. Barrett-Connor instead applied to medical school.
After receiving her medical degree from Cornell University in 1960, Dr. Barrett-Connor completed her internship and residency training in internal medicine at the University of Texas in Dallas. She then moved to the University of Miami for a year of training in infectious disease medicine. There she met James Connor, a pediatric infectious disease doctor.
The two married, he said, while she was on a fellowship at the London School of Hygiene & Tropical Medicine in 1965. His first marriage had ended in divorce. When he was recruited to the University of California, San Diego, in 1970, she joined its faculty as well.
In addition to her daughter and husband, Dr. Barrett-Connor is survived by her sons, Jonathan and Steven Connor; her stepchildren, James Davis Connor Jr. and Susan Connor Way; and eight grandchildren.
Caroline Connor said that she and her father recently discovered that her mother had written more than 5,000 letters to her parents over the years.
She was prolific in her scientific studies as well, Dr. Garland said. He recalled one meeting at which faculty members were discussing which colleagues deserved advancement.
Instead of filling out a standard form listing publications where her work had appeared, Dr. Barrett-Connor had an assistant deliver her recent work to the group.
“This huge stack of papers landed on the table,” Dr. Garland said. The group silently and unanimously approved her promotion. “It was such a profoundly large number of papers during the three-year review period,” he said, “that words were not necessary.”