P332 Does age worsen sleep apnea consequences?

Abstracts / Sleep Medicine 7 (2006) S1–S127

the extent of cognitive deficits in a larger sample of DM1 patients. Design: Two consecutive nights of polysomnography in the sleep unit of an academic hospital and neuropsychological testing at home. Methods and measurements: Forty-two DM1 patients (13 men; M = 50 ± 10 years; M = (CTG) n 846 ± 539) selected without regards to daytime/nocturnal complaints underwent two sequential polysomnographic sessions and neuropsychological testing. Muscular impairment was categorized as mild (n = 7), moderate (n = 6) or severe (n = 29). Only data from the second night are presented herein. Apnea–hypopnea index (AHI) was defined as the average number of apneic/hypopneic episodes per hour of sleep, and SaO2 90% as the percentage of sleep time with oxyhemoglobin saturation below 90%. General intellectual functioning (WAIS-R), attention (Ruff 2 and 7), short-term memory (WAIS-R Digit Span), executive processes (Stroop Color and Word Test), and manual dexterity (Purdue Pegboard) were evaluated. Student’s t tests as well as Pearson’s and Spearman’s correlations were performed. Results: Mean BMI and AHI were 29 ± 7 kg/m2 and 22 ± 15. Apneas and hypopneas were of the obstructive type in 87% of respiratory events. AHI was positively related to BMI (r = .63, p < .001), but not to gender, age, muscular impairment, and (CTG)n. Both AHI and SaO2 90% were negatively correlated to Stroop (r = .47, p < .01 and r = .31, p < .05), Ruff 2 and 7 measures (r = .33 to r = .38, p < .05), and Purdue Pegboard right hand (r = .34, and r = .37, p < 0.05). Also, SaO2 90% was negatively correlated to Purdue Pegboard left (r = .47, p < .01), and both hands (r = .42, p < .01). Conclusions: The severity of sleep apnea seems to modulate attention and vigilance, executive functioning, and motor performance in patients with DM1, suggesting a role for respiratory problems at night in the cognitive deteriorations often reported in this condition. Further studies should assess whether assisted ventilation improves cognitive functioning in DM1 patients with sleep apnea. Funded by the Canadian Institutes of Health Research.

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Methods and measurements: Participants underwent an all-night PSG evaluation followed by a waking EEG recording (10 min/eyes closed). As a measure of cortical slowing, the absolute power in the delta-theta frequency range (0.5–8 Hz) was quantified in all regions. Daytime vigilance was assessed by the Four Choice Reaction Time Test (mean reaction time, lapses, errors). An averaged score of the performance on 4 trials (09.30, 11.30, 13.30, 15.30 h) was calculated. Results: Forty participants were evaluated for the study: 20 controls (mean age 52.9 (10.5) years) and 20 OSAS patients (mean age 48.8 (10.6) years). An age cut-off was established at 55 years, in order to separate younger (OSAS: n = 12, 42.2 ± 8 years; controls: n = 10, 44.9 ± 2 years) and older (OSAS: n = 8, 63.0 ± 2.5 years; controls: n = 10, 60.8 ± 2 years) individuals. Patients who participated in the study were typical cases of moderate to severe OSAS. Younger OSAS patients had lower mean oxygen saturation with more time spent under 90%, with reduced REM sleep percent relative to older OSAS patients (Mann–Whitney U tests, p < 0.05). Group by Age interactions (ANOVAs 2 · 2, p < 0.05) showed that younger OSAS patients had higher absolute delta–theta power than older OSAS patients in frontal regions and than younger controls for the same regions respectively. A main Group effect was observed for temporal anterior regions; OSAS patients had a higher delta–theta power than controls. Daytime vigilance (slower mean reaction time and more lapses) was affected by age in both controls and OSAS patients but did not show a Group by Age interaction. Conclusions: Contrary to our initial hypothesis, we found a cortical slowing in frontal regions in younger OSAS patients compared to older patients. In contrast, daytime performance was worse in older individuals regardless of the condition, suggesting that age does not seem to interact with OSAS for this factor. Our results provide evidence that OSAS may have different consequences as a function of age. doi:10.1016/j.sleep.2006.07.141

doi:10.1016/j.sleep.2006.07.140

P332 Does age worsen sleep apnea consequences? Annie Mathieu *, Stephanie Mazza, Dominique Petit, Jessica Massicotte-Marquez, Anne Decarky, Jacques Malo, Jacques Montplaisir Centre d’etude du sommeil, Hoˆpital du Sacre-Coeur de Montre´al, Que., Canada Objectives: To assess waking EEG and daytime vigilance in OSAS patients as a function of age, compared to control subjects. Design: Controlled laboratory study.

P333 Relations between plasma NT-proBNP and obstructive sleep apnea (OSA) Robert Plywaczewski 1,*, Michal Bednarek 2, Luiza Jonczak 2, Justyna Czerniawska 2, Adam Nowinski 2, Dorota Gorecka 1, Pawel Sliwinski 1 1

National TB and Lung Diseases Research Institute, Department of Respiratory Failure, Warsaw, Poland 2 National TB and Lung Diseases Research Institute, Department of Respiratory Medicine, Warsaw, Poland Objectives: To evaluate associations between plasma NT-proBNP and OSA severity and assess usefulness of