Improving the performance of peripheral arterial tonometry-based testing for the diagnosis of obstructive sleep apnea.

Outside sleep laboratory settings, peripheral arterial tonometry (PAT, eg, WatchPat) represents a validated modality for diagnosing obstructive sleep apnea (OSA). We have shown before that the accuracy of home sleep apnea testing by WatchPat 200 devices in diagnosing OSA is suboptimal (50%-70%). In order to improve its diagnostic performance, we built several models that predict the main functional parameter of polysomnography (PSG), Apnea Hypopnea Index (AHI). Participants were recruited in our Sleep Center and underwent concurrent in-laboratory PSG and PAT recordings. Statistical models were then developed to predict AHI by using robust functional parameters from PAT-based testing, in concert with available demographic and anthropometric data, and their performance was confirmed in a random validation subgroup of the cohort. Five hundred synchronous PSG and WatchPat sets were analyzed. Mean diagnostic accuracy of PAT was improved to 67%, 81% and 85% in mild, moderate-severe or no OSA, respectively, by several models that included participants' age, gender, neck circumference, body mass index and the number of 4% desaturations/hour. WatchPat had an overall accuracy of 85.7% and a positive predictive value of 87.3% in diagnosing OSA (by predicted AHI above 5). In this large cohort of patients with high pretest probability of OSA, we built several models based on 4% oxygen desaturations, neck circumference, body mass index and several other variables. These simple models can be used at the point-of-care, in order to improve the diagnostic accuracy of the PAT-based testing, thus ameliorating the high rates of misclassification for OSA presence or disease severity.

Performance of peripheral arterial tonometry-based testing for the diagnosis of obstructive sleep apnea in a large sleep clinic cohort.

STUDY OBJECTIVES: Peripheral arterial tonometry (PAT)-based technology represents a validated portable monitoring modality for the diagnosis of OSA. We assessed the diagnostic accuracy of PAT-based technology in a large point-of-care cohort of patients studied with concurrent polysomnography (PSG). METHODS: During study enrollment, all participants suspected to have OSA and tested by in-laboratory PSG underwent concurrent PAT device recordings. RESULTS: Five hundred concomitant PSG and WatchPat tests were analyzed. Median (interquartile range) PSG AHI was 18 (8-37) events/h and PAT AHI3% was 25 (12-46) events/h. Average bias was + 4 events/h. Diagnostic concordance was found in 42%, 41%, and 83% of mild, moderate, and severe OSA, respectively (accuracy = 53%). Among patients with PAT diagnoses of moderate or severe OSA, 5% did not have OSA and 19% had mild OSA; in those with mild OSA, PSG showed moderate or severe disease in 20% and no OSA in 30% of patients (accuracy = 69%). On average, using a 3% desaturation threshold, WatchPat overestimated disease prevalence and severity (mean + 4 events/h) and the 4% threshold underestimated disease prevalence and severity by -6 events/h. CONCLUSIONS: Although there was an overall tendency to overestimate the severity of OSA, a significant percentage of patients had clinically relevant misclassifications. As such, we recommend that patients without OSA or with mild disease assessed by PAT undergo repeat in-laboratory PSG. Optimized clinical pathways are urgently needed to minimize therapeutic decisions instituted in the presence of diagnostic uncertainty.

Sleep telemedicine training in fellowship programs: a survey of program directors.

STUDY OBJECTIVES: Telemedicine is a novel modality of health care delivery that can improve patients' access to sleep medicine services, but little is known about telemedicine training during sleep medicine fellowship. We studied telemedicine training prevalence, use, and attitudes of program directors (PDs) and other faculty members, PDs' receptiveness to a standardized telemedicine curriculum, and whether PDs have reviewed existing American Academy of Sleep Medicine (AASM) sleep telemedicine reference materials. METHODS: This was an anonymous online survey of all 86 PDs of accredited sleep medicine fellowships in the United States. RESULTS: Response rate was 45%. Thirteen (33.3%) of the PDs already offer telemedicine experience to their trainees, although none use a standard telemedicine curriculum. Among the 26 (66.7%) PDs not offering telemedicine experience, 38.5% plan to do so and 53.9% agree that it would benefit fellows. Most PDs (57.9%) report faculty using telemedicine now or within the next 3 years. Many PDs agree that telemedicine is technically feasible, but relatively few agree it is financially feasible (82.1% and 38%, respectively). Few PDs have reviewed both primary AASM telemedicine reference materials. Overall, 64.1% of PDs agree that a national sleep telemedicine curriculum could be useful. CONCLUSIONS: Although only a minority of current sleep medicine fellows are exposed to telemedicine, it is likely that most will get some exposure in the next 3 years. PDs' attitudes toward telemedicine vary significantly with respect to feasibility and importance to their programs. Nevertheless, most PDs believe a standardized sleep telemedicine training curriculum could be useful.

Opinion survey of health care providers towards psychogenic non epileptic seizures.

OBJECTIVES: Psychogenic non epileptic seizures (PNES) are challenging conditions to diagnose and manage. Previous workers have investigated the opinion of health care providers towards PNES; still several lacunae remain to be stressed. Amongst health care professionals, opinion of nurses has not been adequately explored. We attempted to identify areas which need more emphasis to provide optimal care to the patients. PATIENTS AND METHODS: We approached 417 health care providers (HCP; primary care, neurology and in-patient nurses) with a questionnaire regarding their opinion of PNES. RESULTS: Total 115 respondents responded to our survey. We found one-thirds of respondent favoured "non-epileptic seizure" as the preferred diagnostic term. Although majority (61%) of responders felt that PNES were involuntary, 48% of nurses felt that PNES are 'fake' and patients have voluntary control over them. Neurologists and nurses expressed high level of confidence in managing patients of PNES. About 1/3rd (35%) of responders did not feel video EEG (vEEG) to be always required for the diagnosis of PNES. Only a minority (15%) of healthcare providers favor unrestricted driving by patients of PNES in setting of ongoing seizures. CONCLUSION: Our findings highlight areas where more emphasis needs to be placed regarding PNES amongst HCPs. More emphasis needs to be placed on the involuntary nature of these episodes within the HCP community. It might be necessary to more strongly address the education of nurses and residents for this condition.

Psychogenic non-epileptic seizures: a challenging entity.

Psychogenic non-epileptic seizures (PNES) are commonly encountered in neurologic practice. They are often misdiagnosed as epileptic seizures and treated as such for several years before a correct diagnosis is established. Such a misdiagnosis has the potential to expose patients to undue risk through several anti-epileptic drugs (AEDs). Patients are also affected in other ways, such as by financial consequences and the limitation of certain daily activities. In this review, we present the contemporary opinion of PNES with attention to clinically relevant salient features and management strategies.