60 Minutes: Gender Matters in Dosage
Last year, the FDA made a change to its dosage recommendation for Ambien (a.k.a. Zolpidem) for women, cutting it in half. Women were metabolizing it differently than men, which could potentially impair their ability to drive the morning after taking this popular sleep aid. But Ambien is the only drug for which the FDA has made this change so far. For 60 Minutes, Lesley Stahl looked into the move and whether it’s a sign of more changes to come.
Stahl said there are many other medical differences between genders, many of which we do not know enough about. Low-dose aspirin lowers heart attack risks for men, but not women. However, it can protect women when it comes to strokes.
Pain receptors, brain wiring, and liver enzymes are all different in men compared to women, so there are plenty of ways that the genders are different. Larry Cahill is a neuroscientist at UC Irvine, and he said his outlook on gender in science has completely changed thanks to examples like these.
60 Minutes: FDA Knowledge of Gender Difference?
Stahl pointed out that 40 million Ambien prescriptions were written in 2013, and it has been on the market for 20 years. That’s a long time for half the population to get the wrong dosage of a drug. Cahill said it is basically an overdose. The FDA credited its changes to research via driving simulation studies.
Dr Sandra Kweder works in the FDA’s office of new drugs, and she talked to 60 Minutes about metabolism differences between genders. Kweder said that women could have a level 45% higher than men, which sounds like a major difference.
However, 60 Minutes unearthed documents proving that the FDA had knowledge about these significant differences as long ago as 1992, but the information did not seem to result in any action. Kweder said that this was a typical result of pharmacology studies of the day, though things are different now.
60 Minutes: Men Vs Women Symptoms
For many years, there was believed to be no difference between genders, outside the reproductive system. According to Cahill, most studies were done on men and extrapolated to women, on the assumption that the fundamentals were the same, outside of hormonal differences.
But he is one of many who say that thinking and research need to change. Noel Bairey Merz, a cardiologist, said that women’s heart attacks are very different from men. Their symptoms are more different, and can include fatigue or an upset stomach. That is atypical of a male presentation, where men have chest pain and radiating arm pain.
Women’s blockages can also be harder to detect on typical scans. One patient had four minor heart attacks and went to five hospitals without getting a proper diagnosis. Dr Bairey Merz said this single-gendered thinking dates back to the genesis of animal research.
60 Minutes: Female Vs Male Stem Cells
Dr Melina Kibbe, a vascular surgeon at Northwestern University Medical School, is on the cutting edge of research using rats and mice. She told Stahl and 60 Minutes that most studies still use only male animals, because of hormones.
“To control for that variable, most researchers study just males,” Dr Kibbe said. Stem cell expert Doris Taylor also did not think about gender differences in men and women. She switched cells in male and female subjects to be able to track the stem cells, and the results were not the same in both genders.
Female stem cells got rid of plaque in male rats, but female rats who received male stem cells did not get similar results. This led to new discoveries using human stem cells, which show variation between genders and tend to be less powerful in men, dying off with age.
60 Minutes: GAO Women’s Drug Health Risks
Taylor said this could be a correlation to early development of heart disease in men, though much more research needs to be done. Could all this open the door to rethinking a lot of what we assume about science and medicine?
According to the Government Accountability Office, eight out of 10 drugs pulled from the market between 1997 and 2001 were a greater health risk to women than men. Now women are required to include women by law in new research, but results are not always analyzed by gender for differences.
60 Minutes wondered what the point was, and Taylor said that averaging the results would not make sense in terms of treatment or efficacy for men or women. But Cahill said that science still needs to catch up to itself and the Pandora’s box these revelations may have released.
60 Minutes: FDA Drugs Reevaluation?
“The status quo is not okay. The way we’re doing business has to change,” Cahill said. Back at the FDA, Stahl wondered whether the government should look back at other drugs. Kweder said that it would be a huge undertaking to reevaluate every drug out there.
She also said that there are individual differences among patients, and doctors are supposed to start from the lowest dose. But 60 Minutes pressed, saying that doctors will work from the administration’s recommendations.
“I think we’re being very aggressive about bringing the most sophisticated science to new drugs and being aggressive about applying the science where we have reason to believe there is a concern to older drugs,” Kweder said.
Stahl reported that the FDA is reviewing some other sleep drugs, but for now, Zolpidem is the only drug for which it has issued different dosages by gender. What do you think about this?