Ricardo C. Barbosa*, Flavio Aloe†, Stella M. Tavares†

*Psychiatry Institute, LIM23, Universidade de São Paulo General Hospital - São Paulo-SP-Brazil;

†Sleep-Wake Disorders Center, Universidade de São Paulo General Hospital, São Paulo-SP-Brazil;

Sleep-Wake Disorders Center - Hospital Israelita Albert Einstein, São Paulo-SP-Brazil.

Introduction:
Sleep-disordered breathing ranges from partial airway collapse and increased upper-airway resistance manifested as loud snoring and brief arousals to total or partial recurrent airway collapse. Obstructive sleep apnea/hypopnea syndrome (OSAHS) leads to risks of motor vehicle accidents, increased cardiovascular morbidity and mortality1. Therefore, even mild degree OSAHS demands an effective treatment. Although nasal CPAP is therapeutically effective, its compliance rate varies among different patient populations. Hence, removable intraoral appliance therapy has become a treatment alternative for OSAHS. The objective of this study is to assess treatment effectiveness of the MLRD2 in 29 OSAHS subjects.

Methods:
29 PSG-confirmed OSAHS patients were included, 23M/6F, age= 36 to 68, (avg=52), avg BMI = 27.32 ± 4.35. Two RDI subgroups were created. Group 1 OSAHS: RDI>30 (range 113.4 to 33.7), n=19, and Group 2 OSAHS: 29.9>RDI>4.9 (range 28.9 to 5.0). Pre- and post-treatment indexes were obtained at approximately 4 months later for both groups: RDI, Epworth Sleepiness Scale (ESS) subjective daytime sleepiness scores2, min.SatO2%. Student's t-test were employed to compare groups. Miminal treatment outcome criteria were RDI<10 event/hour, min.SatO2%> 90% and ESS < 10 points.

Results:
The results are presented in Table and graphic below

Discussion:
Pre- and pos-treatment RDI, ESS, min Sat O2.% were statistically different confirming the MLRD efficiency in this patient population. However, the RDI was the only parameter that reached a statistically significant difference between group 1 and 2. This confirms intraoral appliances are more efficient in lower RDI patient populations. The pattern of post-treatment improvement ranked ESS score<10 points, RDI<10, minSatO2%> 90% and lastly, miminal treatment outcome criteria for both groups. MLRD-induced improvement in ESS-measured subjective sleepiness has been reported2. Yet, the degree of oxygen desaturation relates to respiratory event duration. This suggests that the intraoral appliance fitted in this patient population is more efficient in reducing the number of arousals, and in reducing the number than reducing the duration of abnormal respiratory events.

Conclusion:
ESS and RDI intraoral appliance-induced clinical improvement is more robust than min.SatO2..

Bibliography

1. Peppard P, Young T, Palta M, Skaturd J Prospective Study of the Association between Sleep-Disordered Breathing and Hypertension.. New Engl J Med, v.342, p.1378-1384, 2000.

2. Barbosa RC, Aloe F, Tavares SM, Silva AB. Evaluation of daytime sleepiness in 115 subjects treated with Mandibular Lingual Repositioning Device - MLRD. Sleep Res 1996; v.25, p. 191.

 
Current Claim: ESS and RDI intraoral appliance-induced clinical improvement is more robust than minSatO2..