Dimensions of sleepiness and their correlations with sleep-disordered breathing in mild sleep apnea

Abstract

Objective: There are many ways of assessing sleepiness, which has many dimensions. In patients presenting a borderline apnea-hypopnea index (AHI, expressed as events/hour of sleep), the mechanisms of excessive daytime sleepiness (EDS) remain only partially understood. In the initial stages of sleep-disordered breathing, the AHI might be related to as-yet-unexplored EDS dimensions. Methods: We reviewed the polysomnography results of 331 patients (52% males). The mean age was 40 ± 13 years, and the mean AHI was 4 ± 2 (range, 0-9). We assessed ten potential dimensions of sleepiness based on polysomnography results and medical histories. Results: The AHI in non-rapid eye movement (NREM) stage 1 sleep (AHI-N1), in NREM stage 2 sleep (AHI-N2), and in REM sleep (AHI-REM) were, respectively, 6 ± 7, 3 ± 3 and 10 ± 4. The AHI-N2 correlated significantly with the greatest number of EDS dimensions (5/10), including the Epworth sleepiness scale score (r = 0.216, p < 0.001). Factor analysis, using Cronbach's alpha, reduced the variables to three relevant factors: QUESTIONNAIRE (α = 0.7); POLYSOMNOGRAPHY (α = 0.68); and COMPLAINTS (α = 0.55). We used these factors as dependent variables in a stepwise multiple regression analysis, adjusting for age, gender, and body mass index. The AHI-N1 correlated significantly with POLYSOMNOGRAPHY (β = −0.173, p = 0.003), and the AHI-N2 correlated significantly with COMPLAINTS (β = −0.152, p = 0.017). The AHI-REM did not correlate with any factor. Conclusions: Our results underscore the multidimensionality of EDS in mild sleep apnea.Keywords: Disorders of excessive somnolence; Sleep apnea syndromes; Sleep, REM; Polysomnography. ResumoObjetivo: Há muitas formas de avaliação da sonolência, a qual possui diversas dimensões. Em pacientes com um índice de apneia-hipopneia (IAH, expresso em eventos/hora de sono) limítrofe, os mecanismos da sonolência excessiva diurna (SED) permanecem apenas parcialmente esclarecidos. Nos estágios iniciais do transtorno respiratório do sono, o IAH pode estar relacionado a outras dimensões da SED ainda não exploradas. Métodos: Revisamos os resultados de polissonografia de 331 pacientes (52% do sexo masculino). A idade média foi de 40 ± 13 anos e o IAH médio de 4 ± 2 (variação, 0-9). Avaliamos dez dimensões potenciais de sonolência com base nos resultados da polissonografia e da história médica. Resultados: O IAH em sono non-rapid eye movement (NREM) estágio 1 (IAH-N1), em sono NREM estágio 2 (IAH-N2), e em sono REM (IAH-REM) foram, respectivamente, 6 ± 7, 3 ± 3 e 10 ± 4. O IAH-N2 se correlacionou significantemente com o maior número de dimensões de SED (5/10), incluindo o escore da escala de sonolência de Epworth (r = 0,216, p < 0,001). Análise de fatores, utilizando-se o alfa de Cronbach, reduziu as variáveis a três fatores relevantes: QUESTIONÁRIO (α = 0,7); POLISSONOGRAFIA (α = 0,68); e QUEIXAS (α = 0,55). Usando esses fatores como variáveis dependentes na regressão múltipla, ajustando para idade, gênero e índice de massa corporal, o IAH-N1 se correlacion...

Obstructive sleep apnea related to rapid-eye-movement or non-rapid-eye-movement sleep: comparison of demographic, anthropometric, and polysomnographic features

“…( 7 - 9 ) We find it interesting that the AHI-REM has been shown to be comparable between men and women. ( 37 ) In our study, there was no significant difference between genders in terms of the prevalence of REM-related OSA. However, we found that REM-related OSA was more common than was NREM-related OSA among the women in our sample, whereas NREM-related OSA was more common among the men.…”

“…( 7 - 9 ) Interessantemente, já foi demonstrado que o IAH-REM é comparável entre homens e mulheres. ( 37 ) Em nosso estudo, não houve diferença significativa entre os sexos em termos da prevalência de AOS-REM. Porém, observamos que a AOS-REM foi mais comum do que a AOS-NREM entre as mulheres de nossa amostra, enquanto a AOS-NREM foi mais comum entre os homens.…”

Repeating administration of Epworth Sleepiness Scale is clinically useful

“…Despite the importance of this symptom in the OSAHS, there is considerable controversy regarding the reliability of methods used for sleepiness estimation [4]. Measuring sleepiness is complicated by its multiple dimensions [5][6][7]. The Epworth Sleepiness Scale (ESS) [8] became a widely used tool to help in the OSAHS diagnosis [9][10][11][12][13][14][15][16][17], besides detecting sleepiness in Parkinson's disease [18], mental disorders [19], and insomnia [20].…”

Estimation on Three-dimensional Motion Parameters in Binocular Vision of Robot Tracking and Control System

“…The disadvantage of optic flow method is that there is great noise and error, and the additional constraint condition is not perfect, which makes it difficult to recover three-dimensional motion and structure from optic flow with noises [2]. However, characteristic method completely depends on correspondence problem [4]. But the method is difficult to be implemented, which makes many researches based on three-dimensional motion estimation implement under the condition that characteristic correspondence problems have been solved.…”