Mild to Moderate Sleep Respiratory Events

Clinical diagnosis of sleep apnea based on single night of polysomnography vs. two nights of polysomnography

“…These findings are consistent with that of Chediak et al [15], since they similarly found that, at an AHI cut-off at 5, 22% of the study patients remained undiagnosed. The results of this study also support the findings of Le Bon and colleagues [10], who found a 15-20% increase in the detection rate of sleep apnea when a second night of polysomnography was added. Furthermore, the data were analyzed to find the proportion of patients who would have remained undiagnosed based on the results of the first night AHI.…”

“…The night-to-night variability is generally attributed to "the first-night effect" [10,16], and where variability exists, the AHI from the second night is generally believed to be greater than first-night AHI. However, Riedel and colleagues [19], in a study comparing first-night sleep variables to second night sleep variables in a group of older adults, found that 26% of the study sample displayed what is called a "reverse first-night effect" where the second night of polysomnography is worse than the first night in terms of both quality and quantity of sleep.…”

“…The AHI cut-offs of 5, 10, or even 15 (respiratory disturbances per hour) have commonly been used as a clinical diagnostic measure of sleep apnea. However, several studies [10][11][12][13][14][15] have shown that there exists a night-to-night variability in the respiratory recordings of overnight PSG. This variability is possibly due to the first-night effect, wherein individuals might find it difficult to sleep in a different environment.…”

“…Home-based sleep studies, where one would assume that the first-night effect would not be a factor, have reported similar instances of misdiagnosis of sleep apnea based on only one night of recordings [14]. Due to the presence of such night-to-night variability in the respiratory recordings, as well as the significant proportion of misdiagnoses, two nights of polysomnography is suggested as the ideal method of diagnosis of sleep apnea [10,12,13].…”

Guidelines for the Recording and Evaluation of Pharmaco-Sleep Studies in Man: The International Pharmaco-EEG Society (IPEG)

“…The FNE phenomenon has been replicated in many studies with healthy participants [43,53,54], psychiatric patients [44,52,55,56], epileptics [57], juvenile rheumatoid arthritics [58] and in subjects with chronic fatigue syndrome [59], although the magnitude of the effects varies between groups. In children and adolescents with sleep-disordered breathing, FNEs were observed in the sleep parameters but not in the respiratory parameters [60,61,62]. Consequently, it is important to be aware of this phenomenon when designing clinical sleep studies.…”