Conclusion: Only 65% of the patients suggestedcommencing CPAP treatment accepted to do so. Theaverage dropout rate was linear and about 5% per year.The acceptance was significantly correlated to ODI. Com-pliance was not higher for patients with ODI > 30, at the8-year follow-up.

doi:10.1016/j.sleep.2006.07.038

135 Prevalence of subjective residual excessive daytime

sleepiness in patients correctly treated with continuous

positive airway pressure

Xuan-Lan Nguyen *, Dominique Rakotonanahary, Joel

Chaskalovic, Carole Philippe, Chantal Hausser-Haw,

Bernard Lebeau, Bernard Fleury

Universite Pierre et Marie Curie, Service de Pneumologie,

Hopital Saint-Antoine, Paris, France

Objective: This study aimed to assess the prevalence ofresidual subjective excessive daytime sleepiness (EDS)in patients correctly treated with continuous positive air-way pressure after 12 months of treatment.Design: A prospective follow-up study in a cohort of 219consecutive Obstructive Sleep Apnea (OSA) patientstreated with an auto-titrating device.Setting: Participants spent one night in the sleep labora-tory of an Academic Teaching Hospital and were thenfollowed up in their homes.Measurements and results: In 219 correctly treatedpatients (oxyhemoglobin desaturation index >3% =4 ± 2/h), vigilance was regularly assessed, using 4 mea-sures of the Epworth Sleepiness Scale separated by a meaninterval of 108 ± 36 days, and compliance provided by thedevice was obtained. Patients were considered as regularusers if their CPAP use was P4 hours/day and P5 daysa week. Because in 54/219 (25%) patients, Epworth Sleep-iness scores (ESS) continued to vary, during the follow-upperiod (433 ± 73 days) patients were considered as som-nolent if the mean score of the 4 ESS was P11. Thirty-four out of 219 (16%) patients remained somnolent (meanESS = 13 ± 3), including 16 non regular users (compli-ance = 3.00 ± 1.74 h/day during 44 ± 18% of days) and18 regular users. Among the latter ones, only 4 patients(2%) did not present any recognized pathology associatedwith somnolence.Conclusion: Residual subjective EDS was rare when usingan adequate definition for somnolence and compliance.

doi:10.1016/j.sleep.2006.07.039

136 Prediction of uvulopalatopharyngoplasty outcome: Anat-

omy-based staging system versus severity-based staging system

Hsueh-Yu Li 1,*, Ning-Hung Chen 2, Tuan-Jen Fang 1

1 Department of Otolaryngology, Sleep Center, Chang

Gung Memorial Hospital, Taipei, Taiwan2 Department of Pulmonary and Critical Care Medicine,

Sleep Center, Chang Gung Memorial Hospital, Taipei,

Taiwan

Study objective: To evaluate and compare outcomes ofuvulopalatopharyngoplasty (UPPP) for obstructivesleep apnea/hypopnea syndrome (OSAHS) by usingan anatomy-based and a severity-based stagingsystem.Design: Prospective design with retrospective review.Setting: A tertiary care, sleep disorders referral center.Patients: One hundred and ten OSAHS patients (105men, mean age 43 years, AHI of 44.4 ± 28.8 events/h,body mass index of 27.1 ± 3.3 kg/m2).Measurements: An anatomy-based staging system (stagesI–IV) was used to classify OSAHS patients by examiningthe tongue-palate position, tonsil size, body mass index,and craniofacial deformities. Patients were also classifiedas ‘‘mild, moderate, moderate-severe or severe’’ based onpreoperative apnea/hypopnea index (AHI) from poly-somnography (severity-based staging system). The surgi-cal success was defined as a 50% reduction of AHI and apostoperative AHI less than 20 events/h.Intervention: UPPP surgery.Results: The overall success rate of UPPP was 78%, thesuccess rates in mild (90%), moderate (73%), moderate-severe (81%) and severe (74%) diseases were similar(P = 0.10). To the contrary, the success rates in patientswith anatomy-based stages I–IV were 100%, 96%, 65%and 20%, respectively, and were significantly different(P < 0.001). Changes of AHI were significantly correlat-ed with Friedman tongue position (FTP) (r = �0.30,p = 0.0012) and tonsil size (r=�0.42, p < 0.0001). TheFTP (odds ratio=0.43, SE = 0.13, p = 0.005, 95% CI0.24–0.78) and tonsil size (odds ratio = 3.13,SE = 1.53, p = 0.02, 95% CI 1.20–8.17), rather thanseverity-based stage (odds ratio = 0.77, SE=0.18,p = 0.283, 95% CI 0.49–1.23), were predictive of surgicalsuccess.Conclusions: The anatomy-based staging system, ratherthan severity-based staging system, is more reasonablefor the prediction of UPPP outcomes. The anatomy-based staging system can provide better case selectioninformation for patient counseling before UPPPsurgery.

doi:10.1016/j.sleep.2006.07.040

137 The effect of CPAP on obstructive sleep apnea

patients without daytime sleepiness

Peilin Lee 1,2,*, Ching-Ting Tang 3, Bee-Horng Lue 4,

Chong-Ren Yu 4, Pan-Chyr Yang 4

S16 Abstracts / Sleep Medicine 7 (2006) S1–S127