Of course we should. Portable monitors should be used only when OSA is suspected (high pretest probability) with no other medical conditions (lung disease, congestive heart failure, morbid obesity).

Of course you could. We have used ambulatory sleep monitoring in scientific projects (see attachment).

Article Effects of treatment with oral appliance on 24-h blood press...

Diagnosis of OSA can be achieved using polygraphy or portable monitoring with systems that record at least oxygen saturation, airflow, breathing effort, heart rate, and body position. Portable monitoring is reliable if it is performed under the supervision of personnel trained in sleep medicine, and if the subjects investigated have a high pre-test probability for suffering from OSA.

In my experience, there seems to be some debate about when and if this is acceptable, even in research studies. In my lab's upcoming paper (Breslin, J., Spanò, G, Bootzin, R., Anand, P., Nadel, L. & Edgin, J.O. (in press). Obstructive Sleep Apnea and Cognition in Down syndrome, Developmental Medicine and Child Neurology), we examined OSAS using ambulatory PSG. We received one review that bluntly stated that portable PSG was not reliable and should not be used to assess OSAS in children. In scouring the literature we could not find a single study showing data that it wasn't reliable. There seems to be some resistance to this method I don't quite understand- particularly in our case in which it would have been almost impossible to see children without OSAS without home studies.

I wonder what you think of the paper referenced below:

Sleep. 2011 Jun 1;34(6):695-709. doi: 10.5665/SLEEP.1030.

I have copied the abstract for your convenience..

An integrated health-economic analysis of diagnostic and therapeutic strategies in the treatment of moderate-to-severe obstructive sleep apnea.

Pietzsch JB, Garner A, Cipriano LE, Linehan JH.

Source

Wing Tech Inc., Menlo Park, CA, USA.

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) is a common disorder associated with substantially increased cardiovascular risks, reduced quality of life, and increased risk of motor vehicle collisions due to daytime sleepiness. This study evaluates the cost-effectiveness of three commonly used diagnostic strategies (full-night polysomnography, split-night polysomnography, unattended portable home-monitoring) in conjunction with continuous positive airway pressure (CPAP) therapy in patients with moderate-to-severe OSA.

DESIGN: A Markov model was created to compare costs and effectiveness of different diagnostic and therapeutic strategies over a 10-year interval and the expected lifetime of the patient. The primary measure of cost-effectiveness was incremental cost per quality-adjusted life year (QALY) gained.

PATIENTS OR PARTICIPANTS: Baseline computations were performed for a hypothetical average cohort of 50-year-old males with a 50% pretest probability of having moderate-to-severe OSA (apnea-hypopnea index [AHI] ≥ 15 events per hour).

MEASUREMENTS AND RESULTS: For a patient with moderate-to-severe OSA, CPAP therapy has an incremental cost-effectiveness ratio (ICER) of $15,915 per QALY gained for the lifetime horizon. Over the lifetime horizon in a population with 50% prevalence of OSA, full-night polysomnography in conjunction with CPAP therapy is the most economically efficient strategy at any willingness-to-pay greater than $17,131 per-QALY gained because it dominates all other strategies in comparative analysis.

CONCLUSIONS: Full-night polysomnography (PSG) is cost-effective and is the preferred diagnostic strategy for adults suspected to have moderate-to-severe OSA when all diagnostic options are available. Split-night PSG and unattended home monitoring can be considered cost-effective alternatives when full-night PSG is not available.

Like any test used in clinical practice, the optimal use of sleep tests depends not only on the test's sensitivity and specificity, but also on the pre-test probability, the presence of other conditions, daily variations in the condition, the criteria used for scoring, the criteria used for treating, and the ability to provide sufficient treatment. A recent study by the Spanish Group provides analysis from real patients: Effectiveness of Three Sleep Apnea Management Alternatives. They show that home testing for all patients is cheaper strategy.

http://www.ncbi.nlm.nih.gov/pubmed/24293754

Portable sleep studies be performed in patients who are high probability sleep apnea patients and do not have any other cardiopulmonary comorbidity

For complicated patients, a formal sleep study should be performed

The answer depends on the question. Sorry to be stating the obvious but.... If I am interested in exploring sleep disturbance in competent adults with potentially complicated OSA/CSA plus suspected RBD, then I'd want an in lab sleep study. If I am exploring sleep disturbance in individuals with moderate to severe Alzheimer's disease, by contrast, then nothing would be further from my mind. The benefits to diagnostic accuracy of an in lab study would be far outweighed by the potential costs to the patient in terms of distress/confusion or the likelihood that these would produce an entirely non-representative night of sleep.