BACKGROUNDPrevious studies show that sleep-related breathing disorder (SRBD) is common in patients with heart failure (HF) and is associated with increased mortality. This study aimed to determine whether there was significant difference of subjective daytime sleepiness between HF patients with and without SRBD.

METHODSWe enrolled, prospectively, 195 consecutive HF patients with left ventricular ejection fractions (LVEF) < or = 45% and all subjects underwent polysomnography to measure the sleep structure between 2005 and 2008. Patients were then assigned to those with SRBD including obstructive and central sleep apnea (apnea-hypopnea index (AHI) > or = 5/hour of sleep) and those without SRBD (AHI < 5/hour) according to the sleep study. The subjective sleepiness was assessed with Epworth sleepiness scale (ESS).

RESULTSAmong 195 HF patients, the prevalence of obstructive sleep apnea (OSA) was 53% and of central sleep apnea (CSA) was 27%. There was no significant difference of ESS scores between patients without SRBD (NSA) and with SRBD (NSA vs OSA: 6.7 +/- 0.6 vs 7.6 +/- 0.4, P = 0.105 and NSA vs CSA: 6.7 +/- 0.6 vs 7.4 +/- 0.5, P = 0.235, respectively), indicating that SRBD patients had no more subjective daytime sleepiness. Compared with NSA, patients with SRBD had increased arousal index (ArI) (NSA vs OSA: 14.1 +/- 1.4 vs 26.3 +/- 1.5, P < 0.001 and NSA vs CSA: 14.1 +/- 1.4 vs 31.3 +/- 3.5, P < 0.001, respectively), more awake number after sleep onset (NSA vs OSA: 19.2 +/- 1.5 vs 26.2 +/- 1.4, P = 0.01 and NSA vs CSA: 19.2 +/- 1.5 vs 36.9 +/- 4.4, P < 0.001, respectively), and reduced proportion of slow-wave sleep (SWS) (NSA vs OSA: 13.8 +/- 1.7 vs 9.3 +/- 0.7, P = 0.024 and NSA vs CSA: 13.8 +/- 1.7 vs 8.9 +/- 0.9, P = 0.024, respectively).

CONCLUSIONSOSA and CSA remain common in patients with HF on optimal contemporary therapy. Patients with both HF and SRBD have no significant subjective daytime sleepiness compared with patients without SRBD, despite of significantly increased awake number, arousal and decreased proportion of deep sleep stages. It is not a credible way and means to exclude SRBD in patients with HF according to the absence of subjective daytime sleepiness.

Adult ; Aged ; Aged, 80 and over ; Female ; Heart Failure ; physiopathology ; Humans ; Male ; Middle Aged ; Polysomnography ; Sleep Apnea Syndromes ; epidemiology ; etiology

During the past two decades tremendous efforts have been made by the medical community, especially in the fields of forensic medicine and pediatrics, to better understand the etiology, epidemiology and pathophysiology of SIDS. There have been many SIDS reports from developed countries, but few from developing Asian countries. Despite a recent significant decrease in the incidence of SIDS in many developed countries, SIDS continues to be the most common cause of post-neonatal infant death in these countries. This article analyzes the SIDS data (1990-2006) from the Office of the Chief Medical Examiner for the State of Maryland, USA, along with review of the literature with regard to the history, epidemiological and pathophysiological characteristics of SIDS, as well as the recent advances in SIDS research. The changing trends in the diagnosis of SIDS and current challenges to its forensic investigation are also discussed.
Arrhythmias, Cardiac/complications* ; Forensic Medicine ; Humans ; Infant ; Risk Factors ; Sleep Apnea Syndromes/complications* ; Sudden Infant Death/etiology* ; United States/epidemiology*

PURPOSE: This study aimed to evaluate the correlation between associating factors of moderate to severe asthma with obstructive sleep apnea (OSA). MATERIALS AND METHODS: One hundred and sixty-seven patients who visited the pulmonary and sleep clinic in Severance Hospital presenting with symptoms of sleep-disordered breathing were evaluated. All subjects were screened with ApneaLink. Thirty-two subjects with a high likelihood of having OSA were assessed with full polysomnography (PSG). RESULTS: The mean age was 58.8+/-12.0 years and 58.7% of subjects were male. The mean ApneaLink apnea-hypopnea index (AHI) was 12.7+/-13.0/hr. The mean ApneaLink AHI for the 32 selected high risk patients of OSA was 22.3+/-13.2/hr, which was lower than the sleep laboratory-based PSG AHI of 39.1+/-20.5/hr. When OSA was defined at an ApneaLink AHI > or =5/hr, the positive correlating factors for OSA were age, male gender, and moderate to severe asthma. CONCLUSION: Moderate to severe asthma showed strong correlation with OSA when defined at an ApneaLink AHI > or =5/hr.
Aged ; Asthma/complications/epidemiology/*etiology ; Comorbidity ; Cross-Sectional Studies ; Female ; Humans ; Male ; Middle Aged ; Polysomnography/instrumentation ; Severity of Illness Index ; Sleep Apnea Syndromes/epidemiology/etiology ; Sleep Apnea, Obstructive/complications/epidemiology/*physiopathology