Obstructive sleep apnea is a chronic disease whose treatment may require long-term nightly use of relatively cumbersome and expensive breathing equipment that provides continuous positive airway pressure (CPAP) via nasal mask. Compliance with this treatment may be influenced not only by the objective improvement in sleep apnea but also by the patient's subjective perception of the benefit, bed mate or family support, side effects, and cost. The last factor may not be important in Ontario, where 75% of the cost is paid by the Ministry of Health. The goal of this study was to analyze the factors that may influence patient acceptance of nasal CPAP. This was done by tabulating the responses to a detailed questionnaire mailed to 148 patients with obstructive sleep apnea (OSA). There were 96 replies. We were able to contact by telephone an additional 42 patients. The results showed that 105 patients continued to use CPAP at a mean follow-up time of 17 +/- 11 months, some for as long as 6 yr. The majority of patients (81%) perceived CPAP as an effective treatment of the disorder, 5% were unsure, and 14% believed that CPAP was ineffective, despite the resolution of sleep apnea on polysomnography. Subjective improvement reported by the patients was also observed by the family members in 83% of the patients. The most common complaint, voiced by 46% of the patients, was nocturnal awakenings. Nasal problems, such as dryness, congestion, and sneezing, were the second most frequent complaint present in 44% of the responders.(ABSTRACT TRUNCATED AT 250 WORDS)

Summary: Complaint of snoring, which is usually voiced by a patient's bedpartner, frequently leads to investigations in the sleep laboratory that are designed to assess snoring objectively and determine whether it is a symptom of sleep apnea. How well this subjective complaint of the listener is confirmed by the objective measurement of snoring is not known. Consequently, we designed a study i) to test the validity of self-perception of snoring and ii) to compare subjective perception of snoring by the sleep technologist with objective measurement of its frequency and loudness. We studied 613 unselected patients referred to our sleep clinic because of snoring and suspicion of sleep apnea. They all had nocturnal polysomnography that included measurements of snoring, expressed as the number of snores per hour of sleep [snoring index (SI)] and mean (dBmean) and maximum (dBmax) nocturnal sound intensity. Following the sleep study, the technologist (and patient) independently rated a patient's snoring as none, mild, moderate or severe. Kruskall-Wallis test, Spearman rank correlations and Cohen's kappa statistics were used to compare the groups, examine the correlations between subjective and objective measurements, and check the agreement between them. We found that i) most patients who snore (471 of 613) were unaware of this behavior; ii) snoring index increased progressively from the “none” group (median SI = 26) to the “severe” group (median SI = 755), with a significant but moderate correlation between the technologist's impression and SI (r = 0.68, p < 0.0005) and poor correlation between the technologist's impression and dBmean (r = 0.34, p < 0.0005); and iii) most of those patients who claim to be able to judge the severity of their snoring have a different perception of it than the listener, with poor agreement between patient's and technologist's subjective impression (Cohen's kappa = 0.22, 95% confidence limits: 0.14−0.33). We conclude that to a large extent snoring is “in the ear of the beholder”, showing only moderate correlation with objective measurement.

No abstract

This study was designed to assess the subjective and objective effects of uvulopalatopharyngoplasty (UPPP) for treatment of snoring. We mailed a questionnaire dealing with snoring, quality of sleep, and interference with bed-partner's sleep to 100 unselected patients who were referred because of snoring. Replies were received from 69 patients. The answers were analyzed, and the subjective impressions were compared with preoperative and postoperative objective measurements of snoring and apnea. The average (+/- SD) length of follow-up was 45 +/- 20 mo. We found no significant differences in the apnea/hypopnea index, snoring index, and mean and maximal nocturnal sound intensity before and after surgery in this group. However, despite this lack of objective improvement. 78% of patients reported reduction in snoring, and 79% reported improvement in the quality of sleep; 18 of 69 bed partners no longer complained of interference with their sleep compared with only one preoperatively. We conclude that if the purpose of UPPP is to reduce the reported health hazards associated with snoring, then comparison between objective preoperative and postoperative measurements of snoring does not indicate success; if, on the other hand, the purpose of surgery is to alleviate the social hazard, then UPPP partially achieves this goal.

We recently proposed an equation predicting the optimal level of continuous positive airway pressure (CPAP) that abolishes sleep apnea from three simple and easily available parameters: body mass index (BMI), neck circumference, and apnea/hypopnea index (AHI). The present study was designed to validate this equation in a prospective group of patients with sleep apnea returning to the sleep laboratory for CPAP titration study. We studied 26 patients and found that the optimal CPAP was equal to the predicted value in 10 of 26 patients, within +/- 1 cm H2O of the predicted value in another 10 of 26 patients, within +/- 2 cm H2O in four of 26 patients, and outside +/- 4 cm H2O in the remaining two patients. We conclude that (1) optimal CPAP can be predicted to within +/- 2 cm H2O from a few simple measurements, and (2) using predicted CPAP as a starting pressure for CPAP titration, it may be possible to optimize and/or shorten the titration study--a fact with significant implications for reducing the cost of "diagnosis-to-treatment" polysomnography.

No abstract

The purpose of this study was to examine whether snoring adversely affects sleep architecture and sleep efficiency, and thus may account for the frequent complaints of daytime tiredness and fatigue expressed by heavy snorers. We recruited eight self-confessed heavy snorers and six self-confessed nonsnorers. All subjects had full nocturnal polysomnography, including continuous monitoring of snoring, which was quantified by counting the number of snores per hour of sleep (snoring index), the number of snores per minute of snoring time (snoring frequency), maximal and mean nocturnal sound intensity (dBmax and dBmean, respectively). We found that even the self-confessed nonsnorers snored lightly, with significantly smaller frequency and index than the heavy snorers. Sleep architecture was similar in both groups. Distribution of snoring among the sleep stages differed for light and heavy snorers: light snorers snored uniformly throughout all sleep stages, whereas heavy snorers tended to snore more during slow-wave and REM sleep. Snoring frequency and snoring index were similar during all sleep stages in light snorers, but they were higher during slow-wave sleep in heavy snorers. Wakefulness time after sleep onset and sleep efficiency correlated significantly with the snoring index. We conclude that although snoring does not affect sleep architecture in general, it influences sleep efficiency and wakefulness time after sleep onset; this may have an adverse effect on daytime function of heavy snorers.

This study describes a simple method, based on a movable catheter technique, for use during routine polysomnography to identify the site of obstruction, and this has been applied to 51 patients with suspected sleep apnea. The obstruction was found to be retropalatal in 30, retrolingual in 7, and could not be determined in 14 patients (12 had no sleep apnea, 1 did not sleep, and 1 had central sleep apnea). Twelve of these patients had uvulopalatopharyngoplasty with preoperative and postoperative polysomnograms to determine the site of obstruction. The preoperative obstruction was retropalatal in nine and retrolingual in three. Postoperatively, four patients (one with retrolingual obstruction and three with retropalatal obstruction) no longer had sleep apnea. In the remaining eight patients, the site of obstruction was unchanged from the preoperative one. Several conclusions result: 1. the movable catheter technique offers a simple way to determine the site of obstruction in patients with significant obstructive sleep apnea, 2. most such patients obstruct in the retropalatal region, and 3. preoperative localization of the site of obstruction to the retropalatal region does not seem to improve the surgical outcome of uvulopalatopharyngoplasty.