BACKGROUND AND PURPOSE: The aims of this study were to determine the prevalence of sleep-state misperception and to identify any differences in the clinical characteristics of primary insomniacs with and without misperception. METHODS: In total, 250 adult primary insomniacs were enrolled whose objective total sleep time (TST) was more than 120 min, as assessed by full-night polysomnography. Sleep state misperception was defined objectively as a TST of at least 6.5 h and an objective sleep efficiency (SE) of at least 85%. RESULTS: The prevalence of sleep-state misperception in primary insomniacs was 26.4%. The (low) quality of sleep and psychiatric parameters were similar in the two groups, although the objective sleep architecture was relatively normal for the misperception group. Multivariate analysis revealed that both SE and sleep quality were significant factors associated with subjective TST in the misperception group, while only SE was significant in those without misperception. Subjective TST was a significant effect factor with respect to sleep quality in the misperception group, while the Beck Depression Inventory-2 score and age were significant factors in those without misperception. CONCLUSIONS: The clinical characteristics of patients with sleep-state misperception differed from those without this condition. This suggests that these two groups should be separated and the treatment goals tailored specifically to each.
Adult ; Depression ; Humans ; Multivariate Analysis ; Polysomnography ; Prevalence ; Sleep Wake Disorders ; Sleep Disorders, Intrinsic ; Sleep Initiation and Maintenance Disorders

A 63-year-old female with obstructive sleep apnea syndrome (OSAS) presented with clinical features indistinguishable from paradoxical insomnia (PI). Her main complaint was chronic insomnia. Her subjective sleep latency was 2-3 h, subjective sleep time was less than 3 h, despite spending 8 h in bed, and she reported near constant awareness of her surroundings while lying in bed. Her body mass index (BMI) was 22.67 kg/m2, and her neck circumference was 34.5 cm. Nocturnal polysomnography (NPSG) findings indicated severe OSAS. Her total sleep time (TST) was 359 min, sleep latency 13 min, and her apnea/hypopnea index (AHI) was 74.6/h. The aim of this report is to evaluate the association between PI and OSAS cases confirmed by NPSG.
Body Mass Index ; Deception ; Female ; Humans ; Middle Aged ; Neck ; Polysomnography ; Sleep Apnea Syndromes ; Sleep Apnea, Obstructive ; Sleep Wake Disorders, Intrinsic ; Sleep Initiation and Maintenance Disorders