Yes, many CMS are considering actigraphy experimental, citing peer reviewed publications where certain brands of commercially available actigraphs demonstrate very low specificity (ability to detect wakefulness during the sleep period). This is not true of all brands of actigraphs. But perhaps, in the current economic atmosphere, they are ignoring the plethora of good evidence and generalizing the results from some inaccurate actigraphs to ALL actigraphs. It is my feeling that only actigraphs devices with the proper peer-reviewed evidence of accuracy should be reimbursable.
When it comes to actigraphy, compliance can usually be judged from a visual inspection of the data. Because there is always some small amount of motility during sleep, large gaps of complete inactivity usually denote periods when the actigraph was removed. Some varieties of actigraphs even have special technology to help make determinations of periods when the actigraph was off-wrist. It’s up to the analyst to decide if the timing and duration of the actigraph removal were sufficient to make a determination of non-compliance.
While reimbursement is not guaranteed at this point in time, pediatrics is usually an area where an accompanying medical justification suggesting that full PSG is not warranted and not easily tolerated in a particular case can increase your chances of reimbursement because it is more fully in line with recommendations by the published practice parameters papers which indicate that actigraphy is called for in populations where PSG is impossible or not well-tolerated.
In my experience 20% to 30% is the normal range for the “percentage of time spent in motion” measured by actigraphy during the sleep period. Some systems call this value “movement time” while others call it “activity index.” Of course the actual value will also depend on the sensitivity of the actigraph you are using. Less sensitive actigraphs will naturally show less of the small movements which occur during normal sleep. Larger values are associated with “restlessness.” This percent of time spent in motion includes all motion, regardless of whether said motion contributes to an actigraphically scored awakening according to the algorithm employed, and has been used successfully as an outcome measure in studies of conditions like Atopic Dermatitis.
Actigraphy will certainly answer the question about whether there are awakenings associated with desaturations. Because actigraphy is easy to use and inexpensive, the case can certainly be made that it provides an added dimension with very little added effort/cost.
Each actigraph provider should be able to provide you with published, peer-reviewed validation studies using their actigraph with their own algorithms. Beware of providers that can’t provide these or who use algorithms developed for actigraphs that are not their own. In general you will find that actigraphs can be very accurate in patients with good sleep, but less so with patients who have sleep disturbances. It is the actigraphs specificity (ability to distinguish wakefulness) in a particular population that should be examined. In some types of insomnia where patients lay awake but motionless, the accuracy of actigraphy can decrease dramatically. So care must be taken and consideration given to the other symptoms and complaints of a subject when examining actigraphic results.
Some actigraph providers allow export of either activity values and/or sleep-wake determinations based on their sleep algorithm. So actigraphy can be imported into PSG systems that have this capability.
There is no perfect solution to this problem. This is the down-side of the ad-lib study. I have seen some studies that do a daily phone call to the subject which includes reminding them to press the event button to demark the sleep period. This seems to have a limited amount of success. Setting up rules based on activity values or using automated software processes for marking time in bed are viable alternatives and should be used with consistency. The other issue is how to handle event marks that clearly contradict what the actigraph histogram is saying. For example a “goodnight” event mark may be missing but the subject remembers in the middle of the night during a trip to the restroom and presses the button. Or, they remember to make their “good morning” mark sometime during breakfast! This is where the analysts interpretation based on context is important.
Third party payers are sometimes making a blanket decision that ACTIGRAPHY, “is not proven and considered investigational," based on a cursory review of the literature that shows that SOME types of actigraphs in SOME populations show poor specificity. My recommendation is that you find a validation article for your particular type of actigraph (in the relevant population, if it can be found) and submit this to the payer to rebut their decision. Your actigraph provider should be able to help you with this documentation.
In many cases the contents of an actigraph clinical report are customizable. But generally, they’ll consist of demographic information about the patient, a graphical presentation of the Actigram (activity histogram) for the period of the recording and then a tabular presentation of night time and, sometimes, daytime statistics. Again, these statistics can usually be customized but generally present sleep statistics that are familiar to the sleep professional, like Total Sleep Time, Sleep Onset Latency, Sleep Efficiency WASO, etc. All reported values are based only on an estimate of sleep/wake based on the application of a (hopefully) validated algorithm and never include any information about sleep architecture.
Contact us about this feature or to become an expert.
The opinions/insights expressed herein are those of the sponsor and do not reflect the opinions or policies of this magazine or Allied Media, nor do we endorse the sponsor's products and/or services in any way.