Subjective sleepiness and polysomnographic correlates in children scheduled for adenotonsillectomy vs other surgical care

Abstract

Study objective: To compare a validated subjective measure of childhood sleepiness to an objective determination, assess the frequency of problematic sleepiness among children with suspected sleep-disordered breathing (SDB), and examine what standard or investigational polysomnographic measures of SDB predict subjective sleepiness.

Design: Prospective, cross-sectional.

Setting: University-based sleep disorders laboratory.

Participants: Washtenaw County Adenotonsillectomy Cohort.

Intervention: Polysomnography followed by Multiple Sleep Latency Tests (MSLTs) in 103 children aged 5 to 12 years old: 77 were scheduled for clinically indicated adenotonsillectomy, usually for suspected SDB, and 26 for unrelated surgical care. Parents completed the previously validated, 4-item Pediatric Sleep Questionnaire-Sleepiness Subscale (PSQ-SS).

Results: Thirty-three (43%) of the children scheduled for adenotonsillectomy had high PSQ-SS scores, in comparison with only 3 (12%) of the controls (p = .004). The PSQ-SS scores correlated inversely with mean sleep latencies on the MSLTs (rho = -0.23, p = .006). The obstructive apnea index, apnea-hypopnea index, and respiratory disturbance index (which included respiratory event-related arousals identified by esophageal pressure monitoring) each correlated similarly with PSQ-SS scores, as did investigational quantification of esophageal pressures and respiratory cycle-related electroencephalographic changes (each rho approximately 0.30, p < .02). A stepwise regression identified sigma-frequency respiratory cycle-related electroencephalographic changes as the strongest independent predictor of subjective sleepiness among all subjects and particularly among those without obstructive sleep apnea.

Conclusions: Sleepiness is a frequent problem among children with suspected SDB. Subjective sleepiness (PSQ-SS) reflects MSLT results to a limited extent, as in adults. Standard polysomnographic measures of SDB predict subjective sleepiness, but respiratory cycle-related electroencephalographic changes may offer additional clinical utility.

Figure 1

Numbers of subjects with indicated scores on the Pediatric Sleep Questionnaire -- Sleepiness Subscale (PSQ-SS). For the majority of subjects whose parents answered each question-item, the first column represents 0 symptoms endorsed, the second column 1 symptom, the third column 2 symptoms, and the fourth column 3 or 4 symptoms. Distributions are shown for all subjects (A), those scheduled for adenotonsillectomy (B), and those who received other surgical care (C).

Figure 1

Numbers of subjects with indicated scores on the Pediatric Sleep Questionnaire -- Sleepiness Subscale (PSQ-SS). For the majority of subjects whose parents answered each question-item, the first column represents 0 symptoms endorsed, the second column 1 symptom, the third column 2 symptoms, and the fourth column 3 or 4 symptoms. Distributions are shown for all subjects (A), those scheduled for adenotonsillectomy (B), and those who received other surgical care (C).

Figure 1

Numbers of subjects with indicated scores on the Pediatric Sleep Questionnaire -- Sleepiness Subscale (PSQ-SS). For the majority of subjects whose parents answered each question-item, the first column represents 0 symptoms endorsed, the second column 1 symptom, the third column 2 symptoms, and the fourth column 3 or 4 symptoms. Distributions are shown for all subjects (A), those scheduled for adenotonsillectomy (B), and those who received other surgical care (C).

Figure 2

The mean sleep latency (MSL) on the Multiple Sleep Latency Test is plotted against scores on the Pediatric Sleep Questionnaire-Sleepiness Subscale (PSQ-SS).