SLEEP 2011 Abstract Supplement

B. Clinical Sleep Science I. Sleep Disorders – Breathing
tal AHI. It is necessary to perform all night PSGs as percentage of REM
sleep increases in morning. In addition it is important to consider that
night to night variability in REM sleep proportion may affect total AHI.
The study has implication in redefining of the criteria for diagnosis and
treatment of obstructive sleep apnea. This invokes the need for studies
that evaluate the benefit of offering treatment to symptomatic patients
with significant REM-only OSA even if the total AHI does not meet the
criteria for PAP therapy (AHI < 5).
0468
OBESITY BUT NOT OSA ALTERS FUNCTIONAL CAPACITY
Rizzi CF 1,2 , Cintra F 1,2 , Mello-Fujita L 1 , Risso TT 1,2 , Oliveira W 1 ,
Tufik S 1 , Poyares D 1
1
Psychobiology, Universidade Federal de Sao Paulo, São Paulo, Brazil,
2
Medicine, Universidade Federal de Sao Paulo, São Paulo, Brazil
Introduction: There is evidence in the literature that OSA patients have
impaired functional capacity compared to controls. Our previous study
in lean subjects showed similar functional capacity in OSA and control
groups. However, it is known that obesity may impair exercise performance.
Therefore, the role of OSA and obesity in exercise capacity is
still unclear. The aim of this study is to evaluate the exercise performance,
blood and echocardiographic parameters in obese, sedentary
OSA patients compared to matched controls.
Methods: Fifty obese subjects (25 OSA patients) were selected from database
of Sleep Institute of Sao Paulo city, Brazil. The control group was
matched by age, gender and BMI. Inclusion criteria were: both gender,
age between 35 and 65 years, BMI > 30 and < 40 Kg/m2 and sedentarism.
Severe systemic disease, pulmonary or cardiac disease, smoking,
pregnancy and patients receiving treatment for OSA were excluded. All
subjects underwent clinical evaluation, polysomnography, a maximum
limited symptom cardiopulmonary exercise test, 2D-transthoracic echocardiography,
spirometry and blood withdraw. Satistical Analysis: One-
Way ANOVA, Repeated measures ANOVA, Chi-Square; p≤0.05
Results: There were no differences in baseline characteristics between
groups. The mean age were 48.6 ± 6.8 years in OSA patients and 48.7
± 6.9 years in controls (p=0.9) As expected, there were statistical differences
in the AHI (33.6 ± 24.4 events/h vs. 3.2 ± 1.4 events/h; p < 0.01),
arousal index (25.6 ± 20.6 events/h vs. 11.7 ± 7.2 events/h; p < 0.01),
minimal oxygen saturation (82.1 ± 8.7 % vs. 89.8 ± 3.1 %; p < 0.01),
and saturation time below 90% (43.6 ± 85.9 min vs. 0.51 ± 0.9 min; p
< 0.01) in the obese OSA patients and obese controls. There were no
differences between obese OSA and control groups in the peak oxygen
consumption (28.6 ± 10.0 ml/Kg/min vs. 25.9 ± 7.7 ml/Kg/min; p=0.3),
anaerobic threshold (21.9 ± 6.9 ml/Kg/min vs. 19.9 ± 6.4 ml/Kg/min;
p=0.4), respiratory exchange ratio (1.03 ± 0.2 vs. 1.03 ± 0.1; p=0.9), and,
blood pressure and heart rate behavior. In a similar fashion, echocardiographic
and blood samples variables were not different between groups.
Conclusion: OSA did not significantly affect exercise cardio-respiratory
function, and blood and echocardiographic parameters in obese patients.
Support (If Any): AFIP, FAPESP, CNPq, CAPES, CEPE
0469
EXERCISE TESTING IN PATIENTS WITH SLEEP
DISORDERED BREATHING
Mansukhani MP 1 , Allison T 2 , Lopez-Jimenez F 2 , Slocumb NL 1 ,
Somers VK 2 , Caples SM 1,3
1
Center for Sleep Medicine, Mayo Clinic, Rochester, MN, USA,
2
Cardiovascular Diseases, Mayo Clinic, Rochester, MN, USA,
3
Pulmonary and Critical Care Medicine, Mayo Clinic, Rochester, MN,
USA
Introduction: Sleep disordered breathing (SDB) is associated with several
adverse cardiovascular outcomes. Few studies have examined exercise
capacity or cardiovascular responses to maximal exercise testing
and recovery, and results from these studies are conflicting.
Methods: In this large cross-sectional study, we identified 1425 adults
who underwent comprehensive exercise testing between 1/1/2005-
1/1/2010 and within six months prior to first-time diagnostic polysomnography
(PSG). Subjects were categorized by apnea-hypopnea index
(AHI) quartiles: