Len Fishman, chief executive, Hebrew Senior Life

The future of Medicare moved to the forefront of the presidential campaign last week when Mitt Romney chose as his running mate Wisconsin Congressman Paul Ryan, who has proposed a dramatic overhaul of the health care program for the elderly.

Len Fishman, who retires next spring as chief executive of Boston-based Hebrew Senior Life, transformed the Harvard-affiliated nonprofit group from a long-term care organization to an integrated health care and housing system for seniors of all incomes and faiths. Fishman, 61, a past president of the American Association of Homes and Services for the Aging, recently spoke with Globe reporter Robert Weisman about his work at Hebrew Senior Life and the challenges facing the care of a rapidly growing elderly population.

You’ve run Hebrew Senior Life for 12 years. What was your greatest accomplishment?

I would say the greatest accomplishment is, together with our board, shifting the organization’s focus, which historically had been around long-term care, to an organization that’s really focused on serving seniors in the community where they want to be. We’ve also advanced the research that we do to improve the lives of seniors and are teaching almost 1,000 students of the health care professions every year to provide better care to the geriatric population.

How would you describe the state of geriatric medicine today, and how has it changed during your tenure?

Unfortunately, the state of geriatric medicine is declining at the same time we are experiencing this huge increase in the number of seniors. We actually have fewer geriatricians in the United States today than we did 10 years ago. It’s one of the reasons that our health care system in many ways is failing seniors.

Medicare is so expensive and not getting the kinds of excellent outcomes that we should be getting for the money we’re spending. And the problem is becoming larger because an ever-greater proportion of people in hospitals and doctors offices and clinics are elderly patients being served by clinicians who don’t understand well enough their special needs.

The ranks of people over 85 will nearly double in the next 20 years. What challenges will that present to the health care system and economy?

Well, the most expensive health care system in the world has just met the baby boomer age wave. Unless we make some dramatic changes in the way we deliver and pay for health care, the result will be dire. We’re spending 18 percent of GDP [gross domestic product] right now on health care and we will be spending 25 percent of GDP — that’s $1 out of every $4 in the US economy — on health care by 2030. And if we reach that point, the number of things that we will be crowding out, like education and transportation and other social services, will really bring the country to its knees.

Will the federal health care overhaul, known as the Affordable Care Act, help? Do you see it as a net plus, a net minus, or neutral for the senior population?

It will help, first of all, by covering a large proportion of uninsured Americans. So that’s certainly a net plus. It is also encouraging a change that has to happen if we’re going to provide better care more cost effectively, which is changing the reimbursement system. The basic principle is you get what you pay for, and the current system pays providers to provide services. As a result you get lots of emergency department visits, lots of hospitalizations, and lots of tests — and nobody taking responsibility for the entire episode of a patient’s care. The Affordable Care Act is encouraging global payment, which will make providers coordinate care with each other and really invest in upfront preventive care that can avoid more expensive care down the road.

One of the signature events of your tenure was the opening of the NewBridge on the Charles retirement community in Dedham. What lessons have you learned that might be applied to senior health care more broadly?

One of the visions behind that campus was the idea of co-locating a school with senior housing and long-term care. The results of that intergenerational contact have just been amazing. When you think in particular about seniors in long-term care, [they] are not getting enough stimulation, enough contact with the younger generation. Having kids who are regularly visiting them is an amazing gift to frail elders. But it’s also a gift to the kids, many of whom are living far from grandparents and don’t get a chance to sit with an older person for whom that time is precious. So for me, that’s an argument for never building senior facilities in isolation again.