ARTICLE IN BRIEF
In a new practice guideline from the American Academy of Sleep Medicine, a task force of sleep specialists concluded that actigraphy is a useful tool for assessing sleep-wake disorders in children and adults. But they cautioned that actigraphy is not a replacement for in-laboratory polysomnography when an indication exists for such testing.
A task force of sleep medicine specialists convened by the American Academy of Sleep Medicine concluded that actigraphy can be useful for assessing a broad range of suspected sleep or circadian rhythm sleep-wake disorders in children and adults.
The evidence-based assessment, which resulted in eight recommendations labelled as “conditional” or “strong,” was published in the July 15 Journal of Clinical Sleep Medicine. The task force defined a “strong” recommendation as one that clinicians should follow under most circumstances; the “conditional” category “reflects a lower degree of certainty regarding the outcomes and appropriateness of the patient-care strategy for all patients,” according to the guideline. [See “Actigraphy Recommendations” for the task force findings.]
Typically worn on the wrist or ankle, or occasionally on the waist, actigraphic devices record and assimilate the occurrence and degree of limb movement activity over days or weeks.
Actigraphy “provides a useful characterization of sleep beyond what can be obtained from a sleep diary,” lead author Michael T. Smith Jr., PhD, professor of psychiatry, neurology and nursing at the Johns Hopkins University School of Medicine, told Neurology Today.
The tool provides information that can inform diagnosis and treatment, particularly in small children, who aren't able to reliably recall how much time elapsed before they fell asleep and how many awakenings they experienced during the night, Dr. Smith said.
He added that sometimes “it is the only way we can really get a good window into what's going on with sleep patterns over several days.”
Despite the overall moderate quality of evidence due to imprecision, heterogeneity, and limited sample sizes, the task force concluded that the advantages of using actigraphy offset the harms, which are negligible and rare, including skin irritation.
The task force focused entirely on the data on clinical grade actigraphy devices approved by the Food and Drug Administration, excluding non-prescription items marketed directly to consumers.
The review compared actigraphy to sleep logs and polysomnography in determining whether it provides information significantly distinct from patient-reported data and sufficiently consistent with polysomnography results to use as an objective measure.
The task force recommended actigraphy recording for at least 72 hours on 14 consecutive days, in adherence with the Current Procedural Terminology coding requirements.
In both adults and children, the authors found actigraphy to be helpful in differential diagnosis and clinical decision making regarding insomnia disorder. The recommendation for children was based on studies of children and adolescents, ages 3 to 19, and applied to youth with developmental disorders, as well.
The authors cautioned that actigraphy is not a replacement for in-laboratory polysomnography when an indication exists for such testing. However, it can offer objective metrics across a number of sleep-wake disorders to aid in the assessment and monitoring of treatment response.
In adult patients suspected of sleep-disordered breathing, the task force suggested that clinicians use actigraphy integrated with home sleep apnea test devices to estimate total sleep time during recording (in the absence of alternative objective measurements).
The experts also recommended using actigraphy to monitor total sleep time before ordering the Multiple Sleep Latency Test in adult and pediatric patients with suspected central disorders of hypersomnolence. In addition, they suggested that clinicians use actigraphy to approximate total sleep time in adults with suspected insufficient sleep syndrome.
In the only recommendation it characterized as strong, the task force advised against using actigraphy in place of electromyography for the diagnosis of periodic limb movement disorder in adult and pediatric patients.
Previous clinical practice guidelines did not address this particular disorder, the task force noted, acknowledging a burgeoning interest in exploring actigraphy as an alternative to in-laboratory electromyography in conjunction with polysomnography. The recommendation not to use actigraphy as a substitute for the other modalities is mainly due to the lack of dependable estimates of periodic limb movement and the possibility of misdiagnosis, the authors noted.
Clinicians should keep in mind that cost may play a role in patient preferences of sleep testing modalities. Although many insurers reimburse for actigraphy, the authors pointed out that there is substantial variability. If out-of-pocket expenses were not a factor, patient preferences could change.
Given the level of evidence for many of the other sleep disorders, the conditional recommendations are reasonable, said Phyllis C. Zee, MD, PhD, chief of sleep medicine in the department of neurology and the Benjamin and Virginia T. Boshes professor of neurology at Northwestern University Feinberg School of Medicine. However, actigraphy is recommended by the International Classification of Sleep Disorders for assessing and diagnosing circadian sleep-wake disorders.
Dr. Zee noted that in children and older adults with neurodegeneration, there are limited options for evaluating sleep-wake disorders. It is therefore an “essential part of the diagnostic workup to differentiate circadian rhythm sleep-wake disorders from insomnia and hypersomnia disorders,” she explained.
Polysomnography, which is regarded as the gold standard for evaluating sleep disorders, is not designed to track the daytime behaviors and other factors that interfere with nighttime sleep, she said. Activity and light measures from actigraphy devices can provide enlightening data for managing circadian sleep-wake disorders in which therapies such as timed light exposure can be effective forms of treatment, she said.
“We need to move beyond thinking of sleep and its disorders as confined to the sleep period, typically at night,” she said. “Daytime behaviors and activity and light levels influence sleep at night, performance and alertness during the day, and overall physical and mental health.”
Some disorders necessitate 24-hour monitoring over the course of multiple days, including workdays and days off, she said.
“We really need longitudinal recordings of sleep,” said Cathy Anne Goldstein, MD, MS, assistant professor of neurology at the University of Michigan Sleep Disorders Center. Actigraphy often helps fulfill that need, Dr. Goldstein said.
She added that actigraphy documents pre- and post-treatment response to determine if a patient is benefiting from a prescribed intervention — for instance, cognitive behavioral therapy for insomnia.
Dr. Goldstein noted, however, that actigraphy is probably underutilized as a tool in sleep medicine. Among the reasons, she said, is that the time it takes to interpret the output isn't typically reimbursed by insurers, Dr. Goldstein said.
Actigraphy's lower specificity for sleep in spite of high sensitivity is another caveat to keep in mind, she pointed out. Because actigraphy records only movement, non-moving wakefulness is often misinterpreted as sleep.
The utility of actigraphy for the general clinician without specific expertise is questionable as well, said Daniel Lewin, PhD, a pediatric psychologist who is director of pulmonary behavioral medicine and the associate director of sleep medicine at Children's National Health System in Washington, D.C.
“It's a very powerful tool, but it does require some knowledge of basic sleep mechanisms and of how the tool can be used and what variables can be extracted from the tool,” he said.
Dr. Lewin, who has used actigraphy as a research and clinical tool for at least two decades, said the relevant training can be acquired through professional associations in the specialty of sleep medicine.
Some practices remain on the fence about actigraphy. “This discussion has come up many times on whether we should invest in actigraphy devices,” said Joyce Lee-Iannotti, MD, assistant professor at the University of Arizona College of Medicine at Phoenix and director of the Banner University Medical Center Sleep Disorders Center in Phoenix.
But she said she will advocate for actigraphy as their practice grows. “It's added data on top of a sleep diary,” she said. “It's not perfect by any means, but it gives you some objective data other than what the patient reports.”
Actigraphy adds value in helping to clinically diagnose and treat certain sleep disorders, such as insomnia (for example, paradoxical insomnia, a misperception of actual sleep time) and circadian rhythm disorders, such as advanced sleep phase disorder, where patients feel sleepy and retire to bed early in the evening and subsequently wake up very early in the morning, Dr. Lee-Iannotti said.
“It is important to note that actigraphy has limitations and should not replace the value of polysomnography in diagnosing and assessing most sleep disorders,” she said.
Nathaniel F. Watson, MD, professor of neurology at the University of Washington School of Medicine in Seattle, director of the UW Medicine Sleep Clinic, and co-director of the UW Medicine Sleep Center, said the new in-depth guideline “clarifies the unique usefulness of actigraphy in the clinical practice of sleep medicine.”
Actigraphy can be used effectively in many different scenarios — for example, in measuring an individual's sleep duration prior to a Multiple Sleep Latency Test, said Dr. Watson, a past president of the American Academy of Sleep Medicine.
“In order to ensure that we're getting high-quality data during that test, we want to make sure patients are sleep-satiated,” he added. “Actigraphy is an accurate way for us assess that to improve clinical outcomes.”
A downside is that an actigraphic device typically can't collect more than about 14 days' worth of data. “When you're living a typical active human life, sleep can wax and wane, depending on travel patterns, work responsibilities and stress levels,” Dr. Watson said. “This variability in sleep highlights the need for additional technologies capable of assessing sleep over longer periods of time.”
Dr. Goldstein disclosed receiving royalties for work on UpToDate. The other sources quoted reported no conflicts of interest.
The task force made these recommendations for clinicians with the caveat that individual circumstances of the patient, available treatment options, and resources should be considered:
- Use actigraphy to estimate sleep parameters in adult patients with insomnia disorder (conditional).
- Use actigraphy in the assessment of pediatric patients with insomnia disorder (conditional).
- Use actigraphy in the assessment of adult patients with circadian rhythm sleep-wake disorder (conditional).
- Use actigraphy in the assessment of pediatric patients with circadian rhythm sleep-wake disorder (conditional).
- Use actigraphy integrated with home sleep apnea test devices to estimate total sleep time during recording (in the absence of alternative objective measurements of total sleep time) in adult patients suspected of sleep-disordered breathing (conditional).
- Use actigraphy to monitor total sleep time prior to testing with the Multiple Sleep Latency Test in adult and pediatric patients with suspected central disorders of hypersomnolence (conditional).
- Use actigraphy to estimate total sleep time in adult patients with suspected insufficient sleep syndrome (conditional).
- Do not use actigraphy in place of electromyography for the diagnosis of periodic limb movement disorder in adult and pediatric patients (strong).