There is no correct observation from which false conclusions cannot be drawn, sometimes with disastrous effect. An excellent example of the latter phenomenon, to which an article in a recent edition of the New England Journal of Medicine implicitly refers, is the current widespread use of opioids in the United States to treat patients with chronic pain.
It was observed, correctly, that patients who were prescribed opiates to relieve acute, post-operative or cancer pain, did not abuse them. During my career I met hundreds of heroin addicts, but not one of them claimed to have become addicted through medical use of the drug, which is in widespread use in British hospitals.
Another correct observation was that many patients claimed to suffer from chronic pain (I once had a patient who said she had pain in her hair) and went untreated. Putting two and two together to make eighty-seven, many doctors concluded that all that was necessary to ameliorate the situation was to prescribe more opioids for those with chronic pain. They thought that experience showed that the prescription of such drugs would not give rise to problems of abuse.
There was, however, a snag which should have been obvious to any doctor who reflected on his own experience: patients with acute and chronic pain are not the same. It was as if doctors, having observed that insulin treated diabetes, used it for cancer of the prostate (they did try it for schizophrenia).
Chronic pain is, in most cases, not the same as acute pain: it is not merely long-drawn out acute pain. But it has been treated as if it were, and when opioids fail to work, as they usually do, doctors either presume that they are not prescribing enough of them or they prescribe stronger ones. In fact, as the author says, chronic pain is in most cases not so much a signal of physical damage as of emotional and social distress.
Perhaps because the author of the article has received payment from more than one pharmaceutical company, his article fails to mention the role of more than one such company in promoting the incontinent use of opioids. These companies downplayed the risks and exaggerated the benefits of the drugs they were selling, or peddling
Nor does the author mention the pressures on doctors to prescribe for a group of patients who are otherwise very difficult to treat. In the first place, doctors have little time to see their patients and prescriptions are quick; in the second, patients who do not get what they want may take their custom elsewhere and some patients may be physically menacing when they do not get what they want. So doctors often take the line of least resistance and prescribe. A few, alas, have made a small fortune by virtually selling prescriptions.
The legal spread of opioids has resulted in widespread addiction, substitution by heroin, and death by overdose. The author treats the problem of overuse of opioids as if it were merely the result of intellectual error; but while such error was a necessary condition for its development, it was not sufficient. He says:
During the late 1980s and early 1990s, it was argued, largely on moral grounds, that opioids should be available for treating chronic pain, and physicians were persuaded that addiction to opioid treatment would be rare.
But persuaded by what and by whom? The author delicately refrains from saying.
However, he is right to call into question the appropriateness of using severity of pain as a measure of the success of treatment for chronic pain. Since chronic pain is in most cases a signal of distress, treatment should aim at a resumption of normal daily function, which opioids generally serve only to prevent.