Operationalization of the new Pain and Disability Drivers Management model: A modified Delphi survey of multidisciplinary pain management experts.

BACKGROUND: We recently proposed the Pain and Disability Drivers Management (PDDM) model, which was designed to outline comprehensive factors driving pain and disability in low back pain (LBP). Although we have hypothesized and proposed 41 elements, which make up the model's five domains, we have yet to assess the external validity of the PDDM's elements by expert consensus. RESEARCH OBJECTIVES: This study aimed to reach consensus among experts regarding the different elements that should be included in each domain of the PDDM model. RELEVANCE: The PDDM may assist clinicians and researchers in the delivery of targeted care and ultimately enhance treatment outcomes in LBP. METHODS: Using a modified Delphi survey, a two-round online questionnaire was administered to a group of experts in musculoskeletal pain management. Participants were asked to rate the relevance of each element proposed within the model. Participants were also invited to add and rate new elements. Consensus was defined by a greater than or equal to 75% level of agreement. RESULTS: A total of 47 (round 1) and 33 (round 2) participants completed the survey. Following the first round, 38 of 41 of the former model elements reached consensus, and 10 new elements were proposed and later rated in the second round. Following this second round, consensus was reached for all elements (10 new + 3 from first round), generating a final model composed of 51 elements. CONCLUSION: This expert consensus-derived list of clinical elements related to the management of LBP represents a first step in the validation of the PDDM model.

Higher effective oronasal versus nasal continuous positive airway pressure in obstructive sleep apnea: effect of mandibular stabilization.

BACKGROUND: In some individuals with obstructive sleep apnea (OSA), oronasal continuous positive airway pressure (CPAP) leads to poorer OSA correction than nasal CPAP. The authors hypothesized that this results from posterior mandibular displacement caused by the oronasal mask. OBJECTIVE: To test this hypothesis using a mandibular advancement device (MAD) for mandibular stabilization. METHODS: Subjects whose OSA was not adequately corrected by oronasal CPAP at pressures for which nasal CPAP was effective were identified. These subjects underwent polysomnography (PSG) CPAP titration with each nasal and oronasal mask consecutively, with esophageal pressure and leak monitoring, to obtain the effective pressure (Peff) of CPAP for correcting obstructive events with each mask (maximum 20 cmH2O). PSG titration was repeated using a MAD in the neutral position. Cephalometry was performed. RESULTS: Six subjects with mean (± SD) nasal Peff 10.4±3.0 cmH2O were studied. Oronasal Peff was greater than nasal Peff in all subjects, with obstructive events persisting at 20 cmH2O by oronasal mask in four cases. This was not due to excessive leak. With the MAD, oronasal Peff was reduced in three subjects, and Peff <20 cmH2O could be obtained in two of the four subjects with Peff >20 cmH2O by oronasal mask alone. Subjects' cephalometric variables were similar to published norms. CONCLUSION: In subjects with OSA with higher oronasal than nasal Peff, this is partially explained by posterior mandibular displacement caused by the oronasal mask. Combination treatment with oronasal mask and MAD may be useful in some individuals if a nasal mask is not tolerated.

Does age worsen EEG slowing and attention deficits in obstructive sleep apnea syndrome?

OBJECTIVE: The aim of this study was to determine whether EEG slowing is more pronounced in older than younger OSAS patients and to verify whether this cortical slowing is correlated to daytime performance, respiratory perturbation and sleep fragmentation. METHODS: Twelve young OSAS patients (mean age 38.2+/-2.0 y) and 13 older OSAS patients (mean age 62.2+/-1.9 y) along with 13 young controls (mean age 35.8+/-2.0 y) and 14 older controls (mean age 60.2+/-2.0 y) underwent a polysomnographic evaluation followed by a waking EEG recording. As a global index of cortical slowing, a ratio of slow-to-fast frequencies was calculated in all cortical regions. Daytime performance was assessed using the four choice reaction time test. RESULTS: Differences in waking EEG and in daytime performance were analyzed by ANOVAs with Group and Age as factors. Waking EEG did not yield a Group by Age interaction. OSAS patients had higher ratios across all regions than controls. Similarly, daytime performance revealed no Group by Age interaction. However, OSAS patients showed more lapses than controls and older subjects were slower than younger subjects. CONCLUSIONS: Our results indicate that age does not interact with OSAS to worsen the severity of cortical slowing, but age can add to the OSAS effect to worsen daytime performance deficits in OSAS patients. SIGNIFICANCE: The daytime performance deficits observed particularly in elderly OSAS patients warrant a careful clinical assessment of these patients to prevent accidents and injuries.

Deficits in involuntary attention switching in obstructive sleep apnea syndrome.

Cognitive functions are altered in patients with obstructive sleep apnea syndrome (OSAS) and it has been proposed that vigilance and attentional deficits play a pivotal role in all aspects of these deficits. One way to assess attentional system integrity is the study of event-related-potentials (ERP), but only a few ERP studies have been conducted in patients with OSAS. The aim of the study was to use ERP to further assess attentional impairments in these patients. Thirteen OSAS patients and 13 age-matched controls underwent a night of polysomnographic recording. Each subject was also tested with an ERP paradigm where standard (95%, 1000Hz), high deviant (2.5%, 1250Hz) and low deviant (2.5%, 1050Hz) tones were presented. Subjects were asked to ignore the stimuli and read during the task. Mismatch negativity (MMN) and P3a amplitudes and latencies were measured. No between-group difference was observed for sleep stages, except a lower percentage of rapid eye movement (REM) sleep in patients with OSAS (p<0.01). Moreover, the OSAS group showed a higher micro-arousal index and more sleep transitions than the control group (p<0.05). A significant group effect was found for the amplitude of the P3a component (p<0.05) that was lower in patients with OSAS for both high and low deviant tones. No between-group difference was found for the MMN and the P3a latencies. In conclusion, patients with OSAS have specific alterations of the P3a component that reflects involuntary attention switching, but automatic auditory processing assessed by MMN appears to be preserved.

Attentional deficits in patients with obstructive sleep apnea syndrome: an event-related potential study.

OBJECTIVE: Patients with obstructive sleep apnea syndrome (OSAS) show cognitive deficits, vigilance alteration and attentional decline. The aim of this study was to use event-related potentials (ERP) to further document the attentional impairments in these patients. METHODS: Twelve OSAS patients and 12 age-matched controls underwent the ERP task which consisted in the presentation of short (50ms, 50%) and long tones (400ms, 50%). For these two categories, 90% were standard (1000Hz) and 10% were deviant tones (750 or 1250Hz). Subjects had to discriminate short and long tones by a motor response. RESULTS: OSAS patients had a sustained and delayed P300 in comparison with control subjects following standard tones (p<0.05). A reduction in amplitude was found in OSAS patients for the P3a obtained by the subtraction of standard from deviant tones (p<0.05). No group difference was observed for N1, mismatch negativity and reorienting negativity components. CONCLUSIONS: Apneas and hypopneas produce deficits related to involuntary attentional switch and stimulus classification processing. SIGNIFICANCE: The changes observed in P3a and P300 components further support the hypothesis that attentional deficits play a pivotal role in cognitive deficits noted in OSAS.

Slow-wave sleep and delta power in rapid eye movement sleep behavior disorder.

Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by the loss of normal muscle atonia during REM sleep, leading to an increase of phasic muscle activity and complex motor behaviors during the night. There is some evidence that RBD patients have more of slow-wave sleep (SWS) than healthy elderly subjects. No study has looked at quantitative electroencephalogram analysis during non-REM sleep in either primary or secondary RBD. The aim of this study was to assess the increase of SWS and to analyze different electroencephalographic frequency ranges during non-REM sleep in 28 idiopathic RBD patients compared with 28 age- and sex-matched healthy volunteers. Idiopathic RBD patients spent more time in SWS (men: 1.4%; women: 5.9%) than control subjects (men: 0.4%; women: 0.6%; p = 0.004). Spectral analyses demonstrated that idiopathic RBD patients had increased all-night delta power in comparison with control subjects (p = 002). This study shows an increase of SWS and power in the delta band during non-REM sleep in idiopathic RBD patients compared with control subjects. Results are discussed about the possible nigrostriatal dopaminergic impairment in RBD patients and the association between RBD and neurodegenerative disorders.