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It was like a bad sitcom: Everything Leo said, his wife Francine said the opposite. He went to the gym, he told me; not since Bush was President, she countered. They’d been going on like this since they entered the exam room. Leo and Francine regularly scheduled joint doctor’s appointments, but today was my first time seeing them—and one of my first times seeing two patients at once.

As I was wrapping up Leo’s visit to move to Francine, she stopped me.

“Can we talk about his vision?”

His eyesight was getting worse, she told me, particularly at night. True to form, Leo denied it—but when I probed further, he admitted that his vision wasn’t what it used to be. Several times, Francine added, he’d also been in near-accidents while driving at night.

Together, the three of us worked out a driving plan where Leo could drive during the day for short distances, and Francine would drive him at night. While Leo had some objections to the agreement, Francine promised that he would follow it. I trusted that she would make sure he did.

When both of them left that day, I couldn’t help thinking that Francine may have saved her husband’s life.

Such shared medical appointments are surprisingly common. As Bloomberg reported earlier this year, the American Academy of Family Physicians estimates that around 10 percent of family physicians now give patients the option to share their appointments with people who have similar health issues. For doctors, the benefits are obvious: Shared appointments are efficient, allowing us to see more of our patients in a day.  But shared appointments can be beneficial for patients, too, helping them to adopt healthy behaviors in a way that one-on-one visits don’t.

A person’s smoking, diet, and exercise habits can depend in large part on the habits of his friends, family, or coworkers. In a landmark study published in The New England Journal of Medicine in 2008, the Yale sociologist Nicholas Christakis found that when a spouse, friend, or sibling quit smoking, it decreased a person’s chances of smoking by 67 percent, 36 percent, and 25 percent, respectively. Other research has found similar positive social-network effects for things like medication adherence. On the consumer side, companies like FitBit and MyFitnessPal use the motivation of a social network to encourage people to exercise.

Much of health, in other words, is a shared experience. There are some conditions, like a cold or a sprained ankle, where doctors’ recommendations are simple and social support won’t make much of a difference. But as a primary-care doctor, I also treat chronic diseases like diabetes and hypertension. The knowledge required to manage these lifelong conditions can be overwhelming for some, and stress makes patients less likely to carry out the instructions that doctors give.

Past research has shown that being around other people may help: In patients with heart failure and diabetes, for example, group visits may improve retention of medical information by 10 to 30 percent. A study presented at the 2014 American College of Cardiology annual meeting, meanwhile, found that being married dramatically lowered one’s chance of heart disease, possibly because spouses helped reinforce medication adherence and exercise habits.

Despite these outcomes, it is easy to see why shared medical appointments aren’t more popular. They go against two principles that have defined medicine: absolute confidentiality, and the individual patient-doctor relationship.

Sometimes, though, that relationship isn’t enough. I don’t have many chances to use shared medical appointments, nor do I feel completely comfortable with them yet—but I know they have the potential to help me reach some of my patients more effectively.

One of my patients has been seeing me for months trying to quit smoking. Her previous primary-care doctor had prescribed everything from nicotine patches to gum to pills. Nothing worked. The reason: Her brother had moved in recently, and smoking together was the one thing they did together. Unless she could get her brother to stop smoking, she told me, it would be impossible for her to quit. I told her to bring her brother to her next appointment—and hopefully, I can convince them to find a new shared activity. As Leo and Francine have taught me, having someone else in the room could make all the difference.

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