Stop Scaring the Mentally Ill

Schizophrenics may be the latest victims of the junk science mob. There seems to be a move afoot to link the leading medication for treating schizophrenia with diabetes.

Zyprexa (olanzapine) is one of a new class of so-called "atypical antipsychotics" that treat not only the "negative" symptoms of schizophrenia (low motivation and diminished motivations) but the "positive" symptoms (delusions and hallucinations) as well.

Zyprexa is the first atypical antipsychotic to show long-term effectiveness in patients with schizophrenia and has been prescribed to nine million people worldwide.

This success seems to have made the medication a target.

A new study published in the Aug. 3 British Medical Journal concluded that Zyprexa "is associated with a clinically important and significant increased risk of diabetes." The researchers reported about a three-to-five-fold increase in diabetes among Zyprexa users compared to non-users of antipsychotics.

Unfortunately for the researchers’ conclusion, though, there were only nine cases of diabetes among the 970 study subjects who used Zyprexa. No doubt this is why the margin of error for the study results was three times larger than the size of the reported increase in risk.

The study was also limited by the researchers’ failure to consider key risk factors for diabetes, including race and weight gain, as possibly being responsible for the observed cases of diabetes among study subjects.

There are some other studies that purport to show a causal link between atypical antipsychotics and diabetes, but these studies report similarly weak statistical results based on data of unknown-to-suspect reliability.

USA Today trumpeted one of these studies with the headline "Anti-psychotic drug linked to diabetes" -- even though the study data was not collected in a scientific manner and the authors acknowledged their finding did not prove a cause-and-effect relationship.

Finally, all study results to date are hopelessly confounded by the recognized phenomenon of increased incidence of diabetes among people with schizophrenia. This isn’t really unexpected. Schizophrenics tend to suffer from multiple health complications and tend to lead relatively unhealthier and sedentary lifestyles.

So why the rash conclusion? There seems to be some skullduggery occurring.

Bristol Myers Squibb is the source of funding for the British Medical Journal study and is awaiting FDA approval of its own antipsychotic drug (aripiprazole) later this year.

BMS obviously doesn’t want to scare physicians and patents away from antipsychotics altogether. But a little temporary fearmongering might raise enough questions about Zyprexa to give BMS’ Johnny-come-lately drug a fighting chance when it’s finally approved.

Oh, and did I mention that one of the study’s researchers was a BMS employee?

This situation smacks of the 1995 scare involving Pfizer’s calcium channel blockers, a type of blood pressure medication. Researchers released pre-publication study results at a medical conference reporting that CCBs were statistically associated with increased risk of heart attack. Ensuing media reports caused a number of CCB users to stop taking their medication. Two people were reported to have died as a result.

The study turned out to be so flawed, though, that the researchers were forced to apologize to their colleagues. Evidence later turned up linking the scare with a rival pharmaceutical company that manufactured a competitor to CCBs.

Such cutthroat competition is not unusual for the pharmaceutical industry. But patients scared away from their medication pay the price.

Antipsychotic treatments like Zyprexa help people with schizophrenia function day-to-day. Schizophrenia is a condition that must be treated and the new atypical antipsychotic drugs so far are the most effective with fewest side effects.

There are 9 million Zyprexa users worldwide. Clinical research into the atypical antipsychotics-diabetes question is ongoing. Until the results are in, it should take more than poor quality statistics before schizophrenics and their doctors are scared off a beneficial medication.

Steven Milloy is the publisher of , an adjunct scholar at the Cato Institute and the author of Junk Science Judo: Self-defense Against Health Scares and Scams (Cato Institute, 2001).

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