Faculty Bibliography

BACKGROUND: Patients with obstructive sleep apnea/hypopnea syndrome (OSAHS), even those generally compliant with CPAP therapy, often intermittently discontinue CPAP. STUDY OBJECTIVE: Examine the impact of CPAP withdrawal on sleep, sleep disordered breathing (SDB), and daytime function in subjects with varying severity of OSAHS. PATIENTS AND INTERVENTIONS: Forty-two subjects (26M/16 F) with OSAHS (AHI4% = 45.2 +/- 35.5/h pretreatment) on CPAP for 4 months were evaluated on the second night of CPAP withdrawal. Sleep architecture, SDB indices, and subjective/objective daytime function were assessed pretreatment, on CPAP therapy, and after CPAP withdrawal. Comparisons were made between pretreatment and CPAP withdrawal for the entire group, and for subgroups of mild/moderate (AHI4% < 30/h, n = 22) and severe (AHI4% > 30/h, n = 20) SDB. RESULTS: Overall, and for mild/moderate subjects, SDB indices returned to pretreatment values on CPAP withdrawal but with fewer apneas and more hypopneas/RERAs. For severe SDB, the event frequency (AI, AHI4%, and RDI) was lower and O desaturation was improved on CPAP withdrawal. Across SDB severity, sleep architecture showed lower %REM (15.6% vs 12.9%, P = 0.009) on the CPAP withdrawal compared to pretreatment. Stanford Sleepiness Score, MSLT, and PVT measures were not significantly different between pretreatment and CPAP withdrawal. CONCLUSIONS: Over a wide range of SDB severity CPAP withdrawal results in recurrence of SDB, albeit with less severe O desaturation. Subjective/objective daytime function returned to pretreatment levels. Sleep architecture changes on CPAP withdrawal (acute SDB) may reflect reduced sleep pressure compared to pretreatment chronic SDB. Our data suggest detrimental effects of even brief withdrawal of CPAP in subjects with both mild and severe OSAHS. CITATION: Young LR; Taxin ZH; Norman RG; Walsleben JA; Rapoport DM; Ayappa I. Response to CPAP withdrawal in patients with mild versus severe obstructive sleep apnea/hypopnea syndrome. 2013;36(3):405-412.

MPS encompasses a group of rare lysosomal storage disorders that are associated with the accumulation of glycosaminoglycans (GAG) in organs and tissues. This accumulation can lead to the progressive development of a variety of clinical manifestations. Ear, nose, throat (ENT) and respiratory problems are very common in patients with MPS and are often among the first symptoms to appear. Typical features of MPS include upper and lower airway obstruction and restrictive pulmonary disease, which can lead to chronic rhinosinusitis or chronic ear infections, recurrent upper and lower respiratory tract infections, obstructive sleep apnoea, impaired exercise tolerance, and respiratory failure. This review provides a detailed overview of the ENT and respiratory manifestations that can occur in patients with MPS and discusses the issues related to their evaluation and management.

Introduction: During sleep studies, pulse oximetry using forehead relectance (R-ox) may have advantages over transmittance inger oximetry (T-ox) because of its ease of application. R-ox has been shown to be accurate and sensitive overall, but may be more subject to artifact from motion and changes in pressure on the sensor than T-ox. The purpose of the present study was to evaluate the signal loss of these two technologies using two commercially available devices used for home sleep testing of sleep-disordered breathing. Methods: We analyzed consecutive home studies performed in a cohort of 128 subjects (38% M, age 69+8 years, BMI 26.2+5.4kg/m², 267 nights of data) who used the ARES Unicorder (with R-ox) for 1-3 nights as part of a research study and 50 additional subjects (72% M, age 46+12 years, BMI 27.5+5.0kg/m², 50 nights of data) who used a Compumedics Somte (with T-ox) for one night as part of their clinical workup. The oximetry signal for each night was reviewed and oximet ry signal loss (%loss) was tabulated using automated detection followed by manual review. %loss between groups was compared by Mann-Whitney Rank Sum Test and Kolmogorov-Smirnov (KS-test). Results: In R-ox, TIB was 13.6+3.0 hr (over 2 nights); RDI was 24.5+15.2/hr. In T-ox, TIB was 7.6+1.0 hrs (1 night); RDI was 18.9+16.9/ hr. Overall, we could not show a signiicant difference for %loss between the two devices (%loss R-ox vs T-ox: median= 2.2% vs 3.1%; 25th %ile= 0% vs 0%; 75th %=13.7% vs 17.7%, p=ns by both statistical tests). In particular, there was no signiicant difference in the proportion of studies with <10% signal loss ("acceptable") between R-ox and T-ox (66% vs 68%). The two technologies also had similar proportion of studies with >40% signal loss (8% vs 8%). However, in the studies with 10- 40% loss (27% of R-ox and 24% of T-ox) there was signiicantly greater %loss in the R-ox studies (median =20% vs 15%, p=0.02 for rank-sum, p=0.004 KS-test). Conclusion: Overall, our data show equal num!

Introduction: Our previous work in cognitively normal elderly shows sleep-disordered breathing (S

Introduction: Sleep is important for memory, and various parameters of sleep may affect consolidation of spatial memory speciically. Both hippocampal electrophysiological evidence and behavioral performance evidence support roles for slow wave sleep (SWS) and REM sleep in spatial navigation. The role of REM is of particular clinical interest, as sleep disordered breathing (S

RATIONALE: Previous studies have shown that sleep-disordered breathing (S

Introduction: Effects of exercise on dynamic aspects of sleep have not been studied. We hypothesized that exercise alters dynamics of sleep stage transitions in healthy controls and patients with chronic fatigue syndrome (CFS). Methods: Sixteen female healthy controls (age: 38+9 years) and 17 female patients with CFS (age: 41+8 years) underwent overnight polysomnography (PSG) on a baseline night and on a night after their performance of a maximal exercise test. All subjects had an adaptation PSG to mitigate any irst night effect. We calculated transition probabilities and rates between sleep stages (waking, rapid eye movement [REM] sleep, N1, N2 and N3) and cumulative duration distributions of each sleep stage and sleep as a whole. Results: After exercise, healthy controls showed a signiicantly greater probability of transition from N1 to N2 and a lower rate of transition from N1 to wake than at baseline; CFS patients showed a signiicantly greater probability of transition from N2 to N3 and a lower rate of transition from N2 to N1. For both groups, these indings suggest there is improved quality of sleep after exercise. Continuity of sleep in the controls improved after exercise, while CFS patients had less continuous N1 and more continuous REM sleep. Despite their improvement in overall quality of sleep after exercise, CFS patients had a signiicantly greater probability and rate of transition from REM to wake compared to healthy controls. Conclusion: Exercise promotes transitions to deeper sleep stages for both healthy controls and CFS patients, but CFS patients showed coexisting sleep disruption and more fatigue. While exercise had positive effects on dynamic sleep morphology in both healthy controls and CFS patients, CFS patients may not fully normalize their sleep with exercise alone

STUDY OBJECTIVES: Adherence to CPAP therapy is low in patients with obstructive sleep apnea/hypopnea syndrome (OSAHS). The purpose of the present study was to evaluate the utility of measures of sleep architecture and sleep continuity on the CPAP titration study as predictors of both short- and long-term CPAP adherence. METHODS: 93 patients with OSAHS (RDI 42.8 +/- 34.3/h) underwent in-laboratory diagnostic polysomnography, CPAP titration, and follow-up polysomnography (NPSG) on CPAP. Adherence to CPAP was objectively monitored. Short-term (ST) CPAP adherence was averaged over 14 days immediately following the titration study. Long-term (LT) CPAP adherence was obtained in 56/93 patients after approximately 2 months of CPAP use. Patients were grouped into CPAP adherence groups for ST (< 2 h, 2-4 h, and > 4 h) and LT adherence (< 4 h, > 4 h). Sleep architecture, sleep disordered breathing (SDB) indices, and daytime outcome variables from the diagnostic and titration NPSGs were compared between CPAP adherence groups. RESULTS: There was a significant relationship between ST and LT CPAP adherence (r = 0.81, p < 0.001). Neither ST nor LT adherence were related to demographic variables, baseline severity of untreated SDB, sleep architecture, or measures of daytime impairment. Good CPAP adherence groups had significantly lower %N2 and greater %REM on the titration NPSG. A model combining change in sleep efficiency and change in sleep continuity between the diagnostic and titration NPSGs predicted 17% of the variance in LT adherence (p = 0.006). CONCLUSIONS: These findings demonstrate that characteristics of sleep architecture, even on the titration NPSG, may predict some of the variance in CPAP adherence. Better sleep quality on the titration night was related to better CPAP adherence, suggesting that interventions to improve sleep on/prior to the CPAP titration study might be used as a therapeutic intervention to improve CPAP adherence. CITATION: Somiah M; Taxin Z; Keating J; Mooney AM; Norman RG; Rapoport DM; Ayappa I. Sleep quality, short-term and long-term CPAP adherence. J Clin Sleep Med 2012;8(5):489-500.