Health·Second Opinion

'Off-label' antidepressant use lacks evidence, and a link between math skills and your health

Second Opinion is a vital dose of the week's news in health and medicine from reporter Kelly Crowe and CBC Health.

Plus, you won't believe what bees can do

One in three prescriptions for antidepressants is for conditions they were never approved to treat, but where's the evidence? (Shutterstock)

This week, we talk with a researcher who's been searching for evidence that antidepressants work for things other than what the label says. We also have another reason to brush up on your math skills, and an ethical "oops".

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Where's the evidence for unapproved antidepressant use?

Once a drug is on the shelf, doctors can use it to treat anything, regardless of what it says on the label. And research has shown that almost one-third of antidepressants are being prescribed for conditions they were never approved to treat, including insomnia, migraines, pain and even bladder control.

When McGill University researchers went searching for data to support these unapproved uses, they couldn't find any scientific evidence in almost half of the cases. In other words, no one had ever studied whether the drug was effective for the condition it was being used to treat. Researcher Jenna Wong says it's a problem because if the drugs don't work, the patient is needlessly exposed to the risk of side effects. It also wastes money.

As for why doctors were prescribing antidepressants for untested uses, the researchers speculated that sometimes they had no other treatment options. Doctors could also be trying to avoid dangerous drug combinations, or simply trying to prescribe drugs that are covered by patient drug plans. In an accompanying editorial, U.K. researchers urged doctors to prescribe drugs based on evidence, no matter what's written on the label.

Listen to our full interview with Wong:

Doctor rating sites receive a failing grade

It's becoming easier to find online reviews for everything from where to buy a pair of shoes, to where to grab a bite. But how about finding a doctor? U.S. researchers looked at 28 physician-rating websites and found you might not want to base your decision on them, at least for now.

The problem? People aren't posting enough reviews to make them useful. The researchers looked at 600 doctor ratings in three U.S. cities and found most doctors had no more than one review on any site, and a third had no reviews at all.

Know your numbers: arithmetic and better health

Next time a teenager says they want to drop math because it's too hard and they'll never need it, tell them to think again. Understanding probabilities helps people make health decisions, according to a recent presentation by Ellen Peters, at Ohio State University.

Could finishing that math homework improve health? (iStock)

"Many people say 'I hate math' the way they say 'I hate broccoli', as if it's the same thing," she told us. "But numeracy can make your life better in ways that go beyond understanding numbers."

Many smart people have poor numeracy skills, said Peters. Those people are less likely to quit smoking, for example. Asthmatics with poor numeracy skills are more likely to end up in the emergency room. Diabetics with poor numeracy have higher blood sugar levels.

Peters tells patients to ask the doctor for statistics. Her research has shown everybody overestimated their risk when there were no numbers to consider. And consider absolute risk rather than relative risk. "Doubling" sounds much worse than a risk that moves from one to two per cent.

An ethical "oops" is exposed

Researchers in a high-profile study have been called out for an "ethical error". At issue is research that looked at the association between testosterone levels and anemia in older men. The problem is, the men with mild anemia were never informed about their low hemoglobin levels.

An editorial in Jama Internal Medicine this week said researchers had a responsibility to inform participants of the condition, which when treated, can improve various health outcomes.

There's plenty of hand-wringing to go around. The editorial points out the study was signed off on by seven different review boards. It wasn't until the peer review process that "one astute journal reviewer brought the error to the attention of the editors."

For their part, the researchers said they were focused on monitoring adverse outcomes from the testosterone treatment, and didn't even think about informing participants with low hemoglobin. They're now contacting participants to right the wrong.

You won't bee-lieve this

Bumblebees play ball! British researchers have shown you can train bees to solve a complex problem, and they'll even improve on the process. By observing other bumblebees, the intelligent insects learned to move a yellow ball to the centre of a platform where they were rewarded with sugar water. But don't take our word for it. Check out the great video made by the folks at Science!

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