When Sarah, a 52-year-old, nonobese woman sought a second opinion for her severe insomnia, our sleep lab inquired about previous workups. Two sleep centers offered her sleep hygiene instructions, cognitive-behavioral therapy, prescription sedatives, and recommendations for OTC sleep aids including antihistamines and melatonin. She embraced all these strategies to the best of her ability, but 5 years later she had little to show for her efforts. The last piece of advice she received—"you're probably depressed and should start antidepressants"—sent her scrambling through the Internet where she found our Web site, and then traveled 600 miles to our sleep medical center in Albuquerque, NM.

Although her sleep onset insomnia was no longer severe, her sleep maintenance insomnia persisted with awakenings lasting 2 or more hours a few times per week. She was tired and sleepy during the day, presumably from averaging 5¼ hours of sleep per night. Her greatest frustration was the inability to return to sleep in the middle of the night after getting up to urinate. She developed a method to move quickly to the toilet and quickly back into bed, but it never succeeded more than a third of the time. Contemplating the use of a bedpan to speed up the nighttime process, she wondered if she might retain some drowsiness to fall back asleep before the inexorable full awakening triggered several hours of insomnia.

In person, she had the opportunity to vent her frustrations and describe how she saw the problem, after which I initiated a brief motivational interviewing session focusing on one question posed in the following way: "Sarah, has anyone ever explained to you why you wake up at night?" Within a short time, we reached a potential tipping point, where I asked Sarah if she would consider undergoing an overnight sleep study, to which she responded with great skepticism.

At this point, would you be willing to order a PSG, or do you share the sleep testing skepticism of the patient?

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PRACTICE PARAMETERS

The practice parameters for PSG in chronic insomnia can assist in answering this question. There are three "guidelines" that might apply: (1) don't use PSG routinely for chronic insomnia; (2) don't use PSG routinely for chronic insomnia that might be related to psychiatric disorders; and (3) consider PSG in a patient who has failed behavioral or pharmacologic therapy.

So, why are these guidelines not standards? Because a "guideline is a patient care strategy reflecting a moderate degree of clinical certainty," whereas "a standard is a generally accepted patient care strategy reflecting a high degree of clinical certainty." There are only three standards listed in the practice parameters on the use of PSG for insomnia patients, of which one clearly applies to this case. Standard 2 states that "insomnia is primarily diagnosed by clinical evaluation through a careful, detailed medical, psychiatric, and thorough sleep history." The standard is clear, but a diagnosis already has been established for the patient. Upon closer inspection, Standard 3 might apply, "Polysomnography is indicated when sleep-related breathing disorders or periodic limb movement disorder is suspected." But Sarah reports no breathing or movement symptoms.

At this point, do you spend the money for the PSG because she just might have a physiological problem (Guideline 3) or stay with Standard 2, forging ahead with clinical evaluation through an even more careful and detailed medical and psychiatric evaluation and an even more thorough sleep history?

According to the AASM's pronouncements on the general use of standards and guidelines: "These practice parameters define principles of practice that should meet the needs of most patients in most situations. These guidelines are neither inclusive of all proper methods of care nor exclusive of other methods of care reasonably directed toward obtaining the same result. Judgment regarding the propriety of any care strategy ultimately must be made by health care providers with consideration given to individual circumstances presented by the patient, available diagnostic procedures, and extant treatment resources [italics added]." In other words, these practice parameters should prove extremely helpful in your care of many patients, but they also might prove inadequate in various cases where the independent clinical judgment of the practicing physician proves superior.

So, you are on solid ground if you choose to order a PSG, but are you ready to commit? No? Then perhaps you want to know what the AASM says in its closing statements, specific to these insomnia practice parameters: "This evidence based review revealed significant weakness in the published literature concerning the diagnostic utility of polysomnography for clinically evaluating patients with insomnia [italics added]." The AASM readily admits the weaknesses and states the need for more research. Until such research provides more concrete answers, these recommendations should prove useful, but by no means should you treat them as sacrosanct in the care of your insomnia patients.

ASSESSING PRACTICE PARAMETER INCORPORATION

At this point in the patient's examination, you should be sure to assess how you have integrated practice parameters into your clinical work and be sure you have developed the proper screening assessments for atypical cases.

Practice standards are important in any field of medicine, but they are especially so in sleep medicine because sleep is a blossoming subspecialty. While new clinical and research discoveries confirm the increasing value of a sleep medicine health perspective, the field is simultaneously disadvantaged by a relatively small legion of clinicians and researchers. Practice standards are a critical imperative that overcomes the field's lack in numbers. In the short and long run, the evolving practice standards of sleep medicine will enhance the field's recognition and credibility from a vast array of physicians and other providers whose respect not only will bolster the business end of the field through increasing patient referrals, but also will solidify the standing of sleep medicine in the broad medical community.

In sleep medicine, a very frequently cited guideline is "Polysomnography is not indicated for the routine evaluation of transient or chronic insomnia," but as described above, this statement is not and has never been a standard; it is a "guideline … based on committee consensus." Does this distinction pose a problem? Yes, because many sleep providers put too much stock in the guideline and treat it as a standard. I cannot begin to count the number of patients I have seen for second opinions, just like Sarah, for whom the topic of PSG was never discussed.

Sarah mentioned she'd seen three sleep doctors and one nurse practitioner at two sleep centers, and no one recommended PSG testing at any point. One board-certified sleep doctor informed her that PSG was an option, but then added it was a complete waste of time, so it was never seriously considered. Why do sleep physicians make such a large disconnect between insomnia and PSG? In my opinion, it is because they read standards or guidelines too literally, and more importantly, they do not heed the warnings offered by the writers of these standards, namely, "you're the doctor; you have access to more information to refine your clinical judgments; and, unquestionably, you have the authority and duty to act outside the standards to give your patient the best care."

In other words, if you find yourself repeating "no PSG for insomnia" like a mantra without appreciating you've adopted a lockstep mentality—never intended by the American Academy of Sleep Medicine—then you have not properly integrated practice parameters into your clinical setting. In my experience, it is very common to hear, especially among younger physicians, that practice parameters are "rules to follow," which diverts far too much of the clinician's attention away from the insomnia patient's unique circumstances and symptoms.

PSG FOR SARAH?

Taking Sarah's situation into consideration, should she undergo PSG? The correct answer is yes, but not necessarily due to what the standards state. The reason is that Sarah is presenting as an atypical case of sleep-disordered breathing. She suffers from a very frequent symptom observed in sleep-disordered breathing, one that is arguably as common as snoring, yet the symptom itself is not directly related to any overt breathing difficulties. Just like snoring, though, if Sarah used PAP therapy, this symptom would frequently disappear.

It would be awfully parsimonious if the symptom were the insomnia itself. In fact, virtually all nosologies for SDB have insomnia listed as a primary presenting complaint, but the problem here is that there is no sound scientific evidence to show that PAP therapy has a robust treatment effect on insomnia. That is, we cannot predict that insomnia will dissipate with the breathing mask treatment.

What should have led Sarah's sleep providers to order a PSG 5 years ago is that she presented with nocturia.

When SDB causes increasingly negative intrathoraic pressure swings, venous return to the right atrium increases, stretching cardiac muscle cells, thus creating a false fluid overload signal. These muscle cells then release atrial natriuretic peptide (ANP), a natural diuretic that causes the kidneys to increase urine production. PAP therapy reverses the process, and often eliminates nocturia in SDB patients.

Sarah's diagnostic polysomnogram showed a mixed pattern of upper airway resistance syndrome (flow limitation) events and hypopneas throughout the night with worsening in REM stage or supine position to occasional apneas. Oxygenation fluctuated the entire night with numerous desaturations in the 1% to 4% range that mostly remained above 90%, but in REM or supine, oxygen dipped below 90%. On Sarah's titration study, she demonstrated classic expiratory intolerance to fixed CPAP pressures, was switched to BPAP therapy, and titrated to 12/5. The notably wide boost in IPAP and EPAP emerged both as the solution to her expiratory pressure intolerance and as the sufficient pressure to normalize the airflow signal on expiration.

Sarah reports that BPAP therapy resolved 95% of her sleep maintenance insomnia. She also reports a remarkable clinical pearl. When she suffers a bad insomnia week, an infrequent event, she now has the wherewithal to employ sleep hygiene or cognitive-behavioral instructions with greater precision and tenacity, and she notices they are much more effective than they ever were prior to starting BPAP therapy. She is persuaded that treating the physical component of her insomnia makes it much easier to treat the psychological components.

The conclusion of Sarah's case can be nicely summarized by Standard 3: "Polysomnography is indicated when sleep-related breathing disorders or periodic limb movement disorder is suspected." When sleep medical clinicians bear in mind the appropriate index of suspicion for sleep-disordered breathing, they will realize this condition is more prevalent in chronic insomnia patients than might have been erroneously inferred by their misreading of the practice parameters. They also may appreciate that AASM standards were not written to dissuade practitioners from ordering PSG tests, but instead were designed to help you achieve a higher quality of patient care.

Barry Krakow, MD, is medical director at Maimonides Sleep Arts & Sciences Ltd and principal investigator at Sleep & Human Health Institute. He can be reached at .

ARE PRACTICE PARAMETERS ABSOLUTE?

Perhaps the most common example of considering parameters as an absolute may be the physician who erroneously thinks that an AHI of less than 5 means you cannot, should not, and will not recommend a titration or a PAP therapy device to a Medicare patient with upper airway resistance syndrome. Nothing could be farther from the Oath (Hippocratic, Maimonides) you took to practice medicine. If someone suffers from a medical condition you determine affects their mental or physical health, you are ethically bound to inform the patient of the need to treat the condition, irrespective of insurance barriers that might thwart your efforts to treat the patient; and you also are obligated to make some reasonable recommendations on how the patient could obtain a PAP therapy device even if it is not covered by their insurance. To work backward, that is, assuming that a noncovered diagnosis is no longer a diagnosis and therefore no longer requires care is not only a violation of your oath to practice medicine, but in a perfect storm of hostile influences, such actions could be deemed negligent or worse.

KEY READING

Sleep medicine is by no means alone in dealing with the problematic nature of over-reliance on consensus or expert opinions as opposed to evidence-based standards. In the February 25, 2009, issue of JAMA, Tricoci et al describe the pervasiveness of this problem in cardiology where utilization of weak evidence or consensus opinions may often be the rule not the exception. And in the same issue, Shaneyfelt and Centor provide salient and sometimes biting commentary on the impact of financial interests and other biases on guideline development.