Doctors think lots of patients ask for medicine they don’t need. This study says that’s not true.

We know that wasteful spending is a huge problem in health care. Every year, the United States spends $765 billion annually (about one third of our overall health care dollars) on things that do not make Americans any healthier.

This is both a huge problem, and opportunity. If we could make a dent in unnecessary wasteful spending, cut it in half or even a quarter, it would be a huge reduction in health care costs. And that could happen without harming Americans: we’d be eliminating the care that, by definition, isn’t needed.

But if we’re ever going to make a dent in unnecessary spending, such on unneeded MRIs or too much medication we need to understand why there’s all this wasteful spending happening in the first place.

A new paper in JAMA Oncology tries to clear that up: The study, which examined 5,050 patient-physician encounters, found that -- despite doctors’ perceptions -- patients aren’t demanding medicine they don’t need.

Doctors will often site patient requests as one major driver of unnecessary spending. They’ll have someone come in who has heard of a given treatment, maybe saw an add for a certain drug on television, and ask: why can’t I have that? Doctors with demanding schedules may find it easier to acquiesce to patients’ requests rather than haggle over the downsides of the treatment in question.

In theory, that could be one reason we’re wasting money on unnecessary care. In practice though, this new research suggests that’s not the case.

Analyzing the records of more than 5,000 cancer patient visits in Philadelphia, a team of researchers at the University of Pennsylvania found that patients requested additional treatment in 9 percent of conversations with doctors. Of those, only 1 percent of the requests were for “clinically inappropriate” treatment — the other 99 percent were for medicine that would be appropriate for the given prognosis.

“Most of the demands or requests are clinically appropriate and many seem reasonable,” the researchers wrote. “Other patient demands are even desirable. For instance, requests for additional palliative interventions, such as pain medications or insomnia treatments, accounted for 1 in 6 of the demands or requests (15.5%) and provide insight into patients’ symptoms, which is obviously valuable.”

Looking at all of those 5,000 visits together, the researchers found that oncologists comply with demands for unnecessary care in 0.14 percent of patient encounters.

This is a question that the researchers grappled with a bit: if patient demands are significantly low, why does the issue weigh heavily on many physicians?

There’s no one answer here, but the researchers did find that requests for additional treatment were more likely to happen in situations where doctors rated their relationship with their patient as “fair or poor” than those where the relationship was deemed “excellent.”

“Patient demands may make the clinician evaluate the relationship as poorer,” the researchers wrote. “Conversely, worse patient-clinician relationships with less trust may lead to more demands and requests for treatments; without confidence in the clinician, patients may feel as if they have to be their own agents.”