Our purpose was to investigate side effects of sleep apnea treatment by removable oral appliances (OA) that advance the mandible. In 22 patients suffering from obstructive sleep apnea (OSA), questionnaire evaluations, polysomnographies, cephalographies, and dental plaster casts were obtained before initiation of treatment with OA that fully covered both dental arches. Patients were reevaluated after 3 to 12 mo (questionnaires, polysomnographies) and 12 to 30 mo (questionnaires, cephalographies, plaster casts) during continuous treatment. Polysomnographies confirmed improved breathing by OA. All patients experienced persistent alleviation of symptoms after 12 to 30 mo and wished to continue treatment. Side effects were common but only mildly disturbing: mucosal dryness (86% of patients), tooth discomfort (59%), and hypersalivation (55%). Cephalographies revealed a decrease in the mean (+/- SE) upper incisors to maxillary plane angle from 102 +/- 2 degrees at baseline, to 101 +/- 2 degrees after 12 to 30 mo (p < 0.05). Overbite and overjet were also slightly (mean reduction < 1 mm) but significantly reduced. None of these side effects required discontinuation of treatment. OA are an effective therapy of obstructive sleep apnea. Mild side effects are common but rarely require intervention. Nevertheless, close follow-up during long-term therapy by OA is advisable in order to timely detect potentially relevant orthodontic changes.

Background: Portable respiratory inductive plethysmography (RIP) is promising for noninvasive monitoring of breathing patterns in unrestrained subjects. However, its use has been hampered by requiring recalibration after changes in body position. Objectives: To facilitate RIP application in unrestrained subjects, we developed a technique for adjustment of RIP calibration using position sensor feedback. Methods: Five healthy subjects and 12 patients with lung disease were monitored by portable RIP with sensors incorporated within a body garment. Unrestrained individuals were studied during 40–60 min while supine, sitting and upright/walking. Position was changed repeatedly every 5–10 min. Initial qualitative diagnostic calibration followed by volume scaling in absolute units during 20 breaths in different positions by flow meter provided position-specific volume-motion coefficients for RIP. These were applied during subsequent monitoring in corresponding positions according to feedback from 4 accelerometers placed at the chest and thigh. Accuracy of RIP was evaluated by face mask pneumotachography. Results: Position sensor feedback allowed accurate adjustment of RIP calibration during repeated position changes in subjects and patients as reflected in a minor mean difference (bias) in breath-by-breath tidal volumes estimated by RIP and flow meter of 0.02 liters (not significant) and limits of agreement (±2 SD) of ±19% (2,917 comparisons). An average of 10 breaths improved precision of RIP (limits of agreement ±14%). Conclusions: RIP calibration incorporating position sensor feedback greatly enhances the application of RIP as a valuable, unobtrusive tool to investigate respiratory physiology and ventilatory limitation in unrestrained healthy subjects and patients with lung disease during everyday activities including position changes.

Background: Utility indices are used in cost-effectiveness analyses as a measure of quality of life reflecting the patient’s preference for a given health state on a scale anchored at 0 (corresponding to death) to 1 (perfect health). It is uncertain which utility instruments are most suitable for application in patients with the obstructive sleep apnea syndrome (OSA). Objectives: To compare utility indices obtained in OSA patients by various instruments. Methods: In 66 untreated OSA patients (median Epworth score 12, apnea/hypopnea index, AHI, 57/h), five different utility instruments were employed. In 34 OSA patients, changes in utility after 4 months of continuous positive airway pressure (CPAP) were retrieved from published SF-36 data. Results: In 66 OSA patients, median (quartiles) utility indices were: standard gamble 0.97 (0.89; 0.99); time trade-off 0.94 (0.81; 0.99); EuroQol questionnaire (EQ-5D) 0.92 (0.83; 1.00); Euro-thermometer visual analog scale 0.80 (0.70; 0.90); SF-36 questionnaire (SF-6D) 0.75 (0.69; 0.85; p < 0.05 SF-6D and Euro-thermometer utility vs. other indices). Different utility indices were poorly correlated among each other and with AHI and Epworth scores. SF-6D utility after 4 months of CPAP had changed by 0.04 (0.02; 0.12, p = 0.026). Conclusions: Utility indices measured by different instruments vary largely and some indices reflect the impaired quality of life in OSA poorly. Interpretation of cost-effectiveness analyses should account for the utility instrument used.

No abstract

No abstract