It is remarkable to think of how long insomnia has been written about in the medical and general literature, with remedies of alcohol and poppy dating back nearly as far as the earliest known writing (around 7500 BCE). Even more remarkable is that not a single study, ever, has documented health benefits of taking a drug to treat insomnia. Of course, symptom improvement is presumably the reason that some individuals take such medications. However, the growing literature of adverse effects of hypnotic drugs has actually been building for decades.
What will the next generation of sleep physicians be writing about our “modern” sleeping pills, and their claims of improved safety?
Each generation of sleeping pills claims to be safe and effective, until we realize the “safe” part was not quite right, and each new generation of drugs is initially thought (and advertised as such) to be safer. The chart below is a historical timeline of insomnia drugs, with the most recent period, covering the last 75 years, referring mainly to the U.S. market.
In retrospect, we may be tempted to think that the safety issues of prior-generation drugs were obvious – but the cycle seems to repeat. Even thalidomide, the drug that left legions of children with terrible deformities, was initially sold as safe enough even for use in pregnancy for sleep. What will the next generation of sleep physicians be writing about our “modern” sleeping pills, and their claims of improved safety?
Looking Beyond Insomnia Symptoms
Throughout these generations of drugs, the “effective” part has been left essentially up to improvement of symptoms. This seems simple enough – what more is needed than the patient’s experience of improvement? Of course symptom resolution is important, but it cannot be the only standard. If it were, then why would physicians counsel patients against using alcohol (or opium, for that matter) to assist with sleeplessness? Well, hopefully that answer also seems obvious: because those substances carry substantial potential risks.
Alcohol and opiates can actually make sleep objectively worse, even if a person feels subjectively that they slept “better”. So, clearly, we need to consider any drug remedy for sleep as a risk-benefit balance. And surely some patients will accept a purely subjective sense of “better” sleep, even if objective sleep is unchanged (or even worse), and even if substantial side effect risk is incurred, because the symptom relief is so important to the patient.
Health Risks Considered
What we must avoid is the sense that this is an “easy” question, and we must not overlook the need to navigate the risk-benefit balance for each patient individually. It is not at all easy to judge the objective health benefits of sleeping pills. In fact, all published long-term studies of sleeping pill use and medical health have shown only risk.
And while I have been critical of some of that literature, such a lopsided literature should give us pause, especially since I am certain that many patients may be taking comfort in the thought that their treatment is improving their health. Is it? Even the health risks (forgetting whether medications help them) of chronic insomnia have been strikingly questioned by the only large study of insomnia that actually measured objective sleep. In that study, only those with both insomnia symptoms and objective short sleep time carried medical and psychiatric risk over the 10 year time-frame. Insomnia without objective short sleep, or objective short sleep without insomnia, did not carry these risks.
Clearly, we cannot consider insomnia a simple disorder, nor can we consider drug therapy a simple solution.
Much Work Remains
Physicians do not routinely test the objective sleep in patients with chronic insomnia, though increasing data suggests we should be doing more of this – even as insurance increasingly restricts laboratory polysomnography in favor of simplistic sleep apnea kits that don’t measure sleep at all.
Clearly, we cannot consider insomnia a simple disorder, nor can we consider drug therapy a simple solution. Even the most up-to-date review of the literature describes the evidence as “weak”, and offers mainly consensus (opinion) advice.
One thing is certain: we have a lot of work to do in this field.
This story first appeared on Dr. Bianchi’s blog on the Mass General Sleep Division’s website.