Since her appointment as dean of the Mailman School of Public Health at Columbia University in 2008, Dr. Linda P. Fried, a geriatrician, has sought to make the dramatic aging of the world’s population, and its myriad ramifications, one of the pillars of education for the 1,100 graduate students there.

Robert Caplin for The New York Times

Since 1900, life expectancy for the average American has increased by three decades, creating a host of medical, financial and public policy challenges. Just as the school took on AIDS in the 1980s and emergency preparedness in the wake of 9/11, so it is now scrambling to prepare its students to turn this age wave from a public health emergency to an opportunity.

Rigorous exploration of the subject is now high on the school’s agenda. A study by Mailman researchers, released early this month, explored the causes of the lag in life expectancy in the United States, compared with more than a dozen other countries. To the researchers’ surprise, the likely suspects — obesity, smoking, traffic accidents and homicide — were not to blame for the disparity.

Instead, the researchers concluded that “costly specialized and fragmented care,’’ hallmarks of American medicine, are probably to blame — despite a per capita increase in health care spending here that was twice the rate of other countries. “It was shocking to see the U.S. falling behind other countries even as costs soared ahead of them,” said the lead author, Dr. Peter Muennig, assistant professor of health policy and management at the Mailman School of Public Health.

Days before Dr. Muennig’s study was released, I attended a memorial service for Dr. Robert N. Butler at All Souls Unitarian Church on Manhattan’s East Side. Dr. Butler, who died suddenly in July of acute leukemia at the age of 83, all but invented geriatrics as we know it: he was founding director of the National Institute on Aging and created the first full-fledged geriatrics department at an American medical school, the Mount Sinai School of Medicine. Today, 11 of 145 medical schools in America have such departments.

More than any other physician and researcher, Dr. Butler was responsible for turning aging into a discipline unto itself, not an afterthought of various medical specialties. And so I was intrigued to hear at his memorial service that the International Longevity Center — a think tank run by Dr. Butler that produces reams of research on old age, longevity and caregiving — would move to Columbia University and begin a formal collaboration with the Mailman School of Public Health.

That agreement — not precisely a merger, according to Mailman officials — was completed shortly before Dr. Butler’s death. “He was relentless,” said Dr. Jack Rowe, a professor at the public health school, and former president and chief executive of Mount Sinai, in his eulogy. “He drove you crazy.” But Dr. Butler saw the collaboration as “a challenging and significant opportunity,’’ he said. (Dr. Rowe and Dr. Fried will run the longevity center until a permanent director is found.)

It strikes me as significant, too, that the two institutions would join forces. Dr. Butler coined the term “ageism’’ and declared old age “the neglected stepchild of the human life cycles.’’ Academics like Dr. Fried and Dr. Muennig know that it can be neglected no longer, that just as a fragmented health care system cannot contain the exploding costs of specialized care for the elderly, neither can each aspect of this unprecedented longevity — medical, finanacial, political, social — be contained in its own silo.

Sitting in a pew during Dr. Butler’s memorial service, I sensed that the ground had shifted significantly for the elderly and their caregivers. If a new generation of public health students — whether they chose research, clinical work or teaching — come to see geriatrics as central to their mission, then we will have one more advance to thank Dr. Butler for.