Most people get no advice from their doctors about whether or when it's safe to have sex after a heart attack.
These findings are according to a survey of American and Spanish patients under the age of 55.
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Just one in eight women and one in five men reported being counselled on sexual activity within the month following a heart attack. And those who did discuss the topic with their doctors were likely to get overly restrictive instructions, researchers found.
Resume normal sexual activity
"The guidelines say for an uncomplicated heart attack people should be able to resume normal sexual activity after a week," said lead author Dr. Stacy Tessler Lindau, director of the Programme in Integrative Sexual Medicine at the University of Chicago Medical Centre.
Tessler Lindau added that patients often don't know if they had an uncomplicated heart attack, which is one that doesn't result in complications to other organs or body systems.
When patients are confused, "that's when the patient and physician need to speak," she said.
Reduced sexual activity
About one in five heart attacks happen in adults under age 56, the researchers note in the journal Circulation. Heart attacks can lead to reduced sexual activity because people fear sex will trigger another heart attack, they add.
The American College of Cardiology, American Heart Association and European Society of Cardiology all support a relatively quick return to sexual activity after an uncomplicated, or "minor," heart attack.
To see if doctors apply those guidelines in practice, the researchers surveyed 3 501 heart attack patients from 127 hospitals in Spain and the U.S. between 2008 and 2012. The average patient was 48 years old. Two thirds were women. Most participants were sexually active in the year before their heart attack.
Most participants believed doctors should talk about sex and said they felt comfortable discussing the subject with a physician. But only 12 percent of women and 19 percent of men had such a conversation in the month after their heart attack.
Of the minority who did discuss sex with their doctors, about a third were told they could resume sexual activity without restrictions. The others were told to limit sex, to be more passive or to keep their heart rate down.
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Spanish women were almost 40 percent more likely than Spanish men to be given restrictive advice, while U.S women were less likely than U.S. men to be told to restrict their activity. Overall, women in Spain were 36 percent more likely than U.S. women to be told to limit sexual activity.
Further differences by country were evident. For example, most U.S. patients who talked about sex with their doctors reported that they had initiated the discussion, while most of the Spanish patients said their doctor had brought it up.
The results might reflect an overly cautious attitude among doctors who do bring up sex, said Tessler Lindau.
"It could be that the physicians who are motivated to raise the issue are especially cautions throughout and thinking of all potential risk to their patient after a heart attack," she said.
People should ask
Tessler Lindau said people who consider their sexual function important should ask about sex after a heart attack if their doctors don't bring it up first.
"It's fair game," she said. "I think your physician will give you an informed response."
Read: Heart attack
Tessler Lindau said sexual function tends to be important to most people. When she's giving a presentation, she said, she often asks people to decide whether they would rather lose their dominant hand or their sexual function. They typically have to think, she said.
"Sexual function is a basic part of human physical function," she said. "If it's not working – unlike a missing hand – the rest of the world can't see it, but it's crucial."
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Image: Doctor talking to patient from Shutterstock.