Positive airway pressure therapy for sleep-disordered breathing confers short-term benefits to patients with spinal cord injury despite widely ranging patterns of use.

STUDY DESIGN: Prospective, cohort study. OBJECTIVES: To evaluate the effectiveness of bi-level positive airway pressure (PAP) therapy and the patterns of use for sleep-disordered breathing (SDB) in individuals with spinal cord injury (SCI). SETTING: Academic tertiary care center, USA. METHODS: Overall, 91 adults with C1-T6 SCI for ≥3 months were recruited and 74 remained in the study to be evaluated for SDB and follow-up. Individuals with SDB but no nocturnal hypercapnia (NH) were prescribed auto-titrating PAP. Those with NH were prescribed PAP with volume-assured pressure support. Device downloads and overnight transcutaneous capnography were performed at 3, 6, and 12 months to quantify PAP use and effectiveness. Participants kept daily event logs, and quality of life (QOL) questionnaires were performed after 3, 6, and 12 months. RESULTS: Overall, 45% of 91 participants completed the study. There was great diversity among SCI patients in PAP utilization; after 3 months, 37.8% of participants used PAP for ≥70% nights and ≥240 min per night, whereas 42.2% seldom used PAP and 20% used PAP sporadically or for short periods. PAP therapy was effective in improving OSA in 89% and nocturnal hypercapnia in 77%. Higher PAP pressures predicted higher levels of device use. There were marked reductions in symptoms of autonomic dysreflexia (AD) and orthostatic hypotension as well as some improved indices of QOL. CONCLUSIONS: Despite widely diverse patterns of use, PAP therapy may have short-term benefits with regard to QOL and reducing episodes of dizziness and autonomic dysreflexia.

Simplified Approach to Diagnosing Sleep-Disordered Breathing and Nocturnal Hypercapnia in Individuals With Spinal Cord Injury.

OBJECTIVE: To evaluate a strategy of home-based testing to diagnose sleep-disordered breathing and nocturnal hypercapnia in individuals with spinal cord injury (SCI). DESIGN: Case series. SETTING: Referral center. PARTICIPANTS: Adults with C1-T6 SCI (N=81). Individuals were eligible if ≥ 18 years old, with SCI of ≥ 3 months' duration, living within 100 miles of the study site, and not meeting exclusion criteria. Of the 161 individuals recruited from the SCI Model System database who were not enrolled, reasons were not interested in participating, change of location, prior positive pressure ventilation use, or medical contraindication. Ten individuals did not complete the study. INTERVENTIONS: Performance of an unsupervised home sleep apnea test combined with transcutaneous partial pressure of carbon dioxide/oxygen saturation by pulse oximetry monitoring. MAIN OUTCOME MEASURES: Prevalence of sleep-disordered breathing and nocturnal hypercapnia. Clinical and physiological variables were examined to determine which, if any, correlate with the severity of sleep-disordered breathing. RESULTS: Obstructive sleep apnea (OSA) was found in 81.3% of individuals, central sleep apnea (CSA) was found in 23.8%, and nonspecific hypopnea events, where respiratory effort was too uncertain to classify, were present in 35%. Nonspecific hypopnea events correlated strongly with CSA but weakly with OSA, suggesting that conventional sleep apnea test scoring may underestimate central/neuromuscular hypopneas. Nocturnal hypercapnia was present in 28% and oxygen desaturation in 18.3%. Neck circumference was the primary predictor for OSA, whereas baclofen use and obstructive apnea/hypopnea index weakly predicted CSA. Awake transcutaneous partial pressure of carbon dioxide and CSA were only marginally associated with nocturnal hypercapnia. CONCLUSIONS: Unsupervised home sleep apnea testing with transcutaneous capnography effectively identifies sleep-disordered breathing and nocturnal hypercapnia in individuals with SCI.

Development of a measure of knowledge and attitudes about obstructive sleep apnea in children (OSAKA-KIDS).

BACKGROUND: Primary care physicians play an important role in screening for childhood obstructive sleep apnea syndrome (OSAS) that, if untreated, can result in serious complications. OBJECTIVE: To describe the development of the Obstructive Sleep Apnea Knowledge and Attitudes in Children (OSAKA-KIDS) questionnaire for use in measuring physicians' knowledge and attitudes about childhood OSAS and its treatment. DESIGN: Cross-sectional survey to pilot administration of the 23-item OSAKA-KIDS questionnaire, mailed to 1195 community- and academic-based physicians in Louisville, Ky; Philadelphia, Pa; and St Louis, Mo. MAIN OUTCOME MEASURES: Analysis of variance measured differences in knowledge and attitudes between academic- and community-based physicians and between pediatricians and family practitioners. Using stepwise multiple linear regression, we analyzed the associations between various predictors (including specialty, practice setting, and years since medical school graduation) and each item of knowledge and attitudes. All tests were 2-tailed. RESULTS: Questionnaires for 497 respondents (44% female; mean [SD] age, 45.7 [10.5] years; and mean [SD] number of years since medical school graduation, 18.7 [11.0] years) were analyzed. The mean (SD) knowledge score (percentage of 18 possible) was 69.6% (14.6%). In regression analyses, more knowledge was associated with more positive attitudes overall and more recent graduation from medical school; having a more positive attitude was associated with having completed a pediatrics residency and more knowledge about OSAS. CONCLUSIONS: Deficits in basic knowledge about childhood OSAS were observed regardless of physician practice setting and specialty training. More education focusing on the diagnosis and treatment of childhood OSAS and identifying children at risk for OSAS is recommended.

Development of the obstructive sleep apnea knowledge and attitudes (OSAKA) questionnaire.

STUDY OBJECTIVES: To develop and validate a questionnaire that assesses physicians' knowledge and attitudes about obstructive sleep apnea (OSA): the Obstructive Sleep Apnea Knowledge and Attitudes (OSAKA) questionnaire. DESIGN: Questionnaire study. SETTING: Physicians associated with the Washington University Physicians Network. PARTICIPANTS: Twenty physicians in the pilot testing and 115 physicians in the final testing of the instrument. INTERVENTIONS: Physicians completed the OSAKA questionnaire containing sections regarding knowledge about OSA (18 items), attitudes about OSA (five items), and demographics of the study participants. MEASUREMENTS AND RESULTS: Knowledge scores ranged from 0 to 18 (mean+/-SD=13.3+/-2.8). Individual knowledge items did not differ significantly by gender or by whether or not respondents had completed subspecialty training. The five attitude items were significantly correlated with one another. Knowledge scores correlated with the 5-item attitude scale. There was a negative correlation between age and knowledge (r=-0.368, P<0.001) and between age and the single attitude item pertaining to physicians' confidence in managing patients with OSA (r=-0.198, P=0.036); thus, the older the respondent, the lower the knowledge score and the less confident they were in managing patients with OSA. CONCLUSIONS: The OSAKA appears to be a useful instrument to measure physicians' knowledge about OSA, their views on its importance as a clinical disorder, and their confidence in identifying and managing patients with this disorder.