PubMed Health⌕ Search

Biomedical subjects

Deborah L Ruzicka

Publications and source records attributed to Deborah L Ruzicka.

12 recordsLinked to original sources

Sleep-disordered breathing, behavior, and cognition in children before and after adenotonsillectomy.

OBJECTIVES: Most children with sleep-disordered breathing (SDB) have mild-to-moderate forms, for which neurobehavioral complications are believed to be the most important adverse outcomes. To improve understanding of this morbidity, its long-term response to adenotonsillectomy, and its relationship to polysomnographic measures, we studied a series of children before and after clinically indicated adenotonsillectomy or unrelated surgical care. METHODS: We recorded sleep and assessed behavioral, cognitive, and psychiatric morbidity in 105 children 5.0 to 12.9 years old: 78 were scheduled for clinically indicated adenotonsillectomy, usually for suspected SDB, and 27 for unrelated surgical care. One year later, we repeated all assessments in 100 of these children. RESULTS: Subjects who had an adenotonsillectomy, in comparison to controls, were more hyperactive on well-validated parent rating scales, inattentive on cognitive testing, sleepy on the Multiple Sleep Latency Test, and likely to have attention-deficit/hyperactivity disorder (as defined by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) as judged by a child psychiatrist. In contrast, 1 year later, the 2 groups showed no significant differences in the same measures. Subjects who had an adenotonsillectomy had improved substantially in all measures, and control subjects improved in none. However, polysomnographic assessment of baseline SDB and its subsequent amelioration did not clearly predict either baseline neurobehavioral morbidity or improvement in any area other than sleepiness. CONCLUSIONS: Children scheduled for adenotonsillectomy often have mild-to-moderate SDB and significant neurobehavioral morbidity, including hyperactivity, inattention, attention-deficit/hyperactivity disorder, and excessive daytime sleepiness, all of which tend to improve by 1 year after surgery. However, the lack of better correspondence between SDB measures and neurobehavioral outcomes suggests the need for better measures or improved understanding of underlying causal mechanisms.

Adenoidectomy↗

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

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.

Adenoidectomy↗

Snoring predicts hyperactivity four years later.

STUDY OBJECTIVES: Cross-sectional studies implicate snoring and sleep-disordered breathing as potential contributors to hyperactive behavior in some children. However, no prospective cohort study has demonstrated that symptoms of sleep-disordered breathing precede development of hyperactivity. PARTICIPANTS: Parents of 229 children aged 2 to 13 years, recruited at 2 general pediatrics clinics, completed initial and 4-year follow-up surveys. MEASUREMENTS: Surveys included a validated Pediatric Sleep Questionnaire about snoring, sleepiness, and overall risk of sleep-disordered breathing, and the hyperactivity index (expressed as a T-score) within the Conners' Parent Rating Scale. RESULTS: Thirty children (13%) were rated as hyperactive (hyperactivity index > 60) at follow-up. After adjustment for hyperactivity at baseline and stimulant use at follow-up, hyperactivity at follow-up was predicted by baseline habitual snoring (odds ratio = 4.4, 95% confidence interval [1.3, 14.7]) or loud snoring (4.5, [1.2, 17.5]) and by top-quartile composite scores for snoring (5.3, [1.7, 16.8]), sleepiness (3.0, [1.0, 9.4]), or sleep-disordered breathing (4.0, [1.4, 11.6]). CONCLUSIONS: This 4-year prospective cohort study shows that snoring and other symptoms of sleep-disordered breathing are strong risk factors for future emergence or exacerbation of hyperactive behavior. These findings support the hypothesis that untreated childhood sleep-disordered breathing contributes to development of hyperactivity.

Age of Onset↗

Electroencephalographic changes during respiratory cycles predict sleepiness in sleep apnea.

Common polysomnographic measures of sleep-disordered breathing have shown a disappointing ability to predict important consequences such as excessive daytime sleepiness. Using novel analytic techniques, this study tested the hypothesis that numerous, brief disruptions in cortical activity could occur on a breath-to-breath basis during nonapneic sleep. Spectral analysis proved the existence of respiratory cycle-related electroencephalographic changes in each of 38 adult patients evaluated by polysomnography for sleep-disordered breathing. Furthermore, the tendency for sigma (13-15 Hz) electroencephalographic power to vary with the respiratory cycle predicted next-day sleepiness as measured by the multiple sleep latency test. The predictive value was enhanced when the analysis was limited to those 27 patients who had sleep-disordered breathing (more than 5 apneas or hypopneas per hour of sleep). In contrast, nocturnal rates of apneas and hypopneas, as well as minimal oxygen saturation, did not predict sleepiness as well. On average, sigma power increased notably during inspiration, whereas delta (1-4 Hz) power showed a simultaneous decrease. We conclude that electroencephalographic activity shows detectable changes during nonapneic respiratory cycles in adults evaluated for sleep-disordered breathing. Quantification of these changes, which may reflect numerous inspiratory microarousals, could prove useful in prediction of excessive daytime sleepiness.

Adult↗

Method for detection of respiratory cycle-related EEG changes in sleep-disordered breathing.

STUDY OBJECTIVES: In sleep-disordered breathing (SDB), visual or computerized analysis of electroencephalogram (EEG) signals shows that disruption of sleep architecture occurs in association with apneas and hypopneas. We developed a new signal analysis algorithm to investigate whether brief changes in cortical activity can also occur with individual respiratory cycles. DESIGN: Retrospective. SETTING: University sleep laboratory. PARTICIPANTS: A 6 year-old boy with SDB. INTERVENTION: Polysomnography before and after clinically indicated adenotonsillectomy. MEASUREMENTS: For the first 3 hours of nocturnal sleep, a computer algorithm divided nonapneic respiratory cycles into 4 segments and, for each, computed mean EEG powers within delta, theta, alpha, sigma, and beta frequency ranges. Differences between segment-specific EEG powers were tested by analysis of variance. Respiratory cycle-related EEG changes (RCREC) were quantified. RESULTS: Preoperative RCREC were statistically significant in delta (P < .0001), theta (P < .001), and sigma (P < .0001) but not alpha or beta (P > .01) ranges. One year after the operation, RCREC in all ranges showed statistical significance (P < .01), but delta, theta, and sigma RCREC had decreased, whereas alpha and beta RCREC had increased. Preoperative RCREC also were demonstrated in a sequence of 101 breaths that contained no apneas or hypopneas (P < .0001). Several tested variations in the signal-analysis approach, including analysis of the entire nocturnal polysomnogram, did not meaningfully improve the significance of RCREC. CONCLUSIONS: In this child with SDB, the EEG varied with respiratory cycles to a quantifiable extent that changed after adenotonsillectomy. We speculate that RCREC may reflect brief but extremely numerous microarousals.

Adenoidectomy↗

Correlates of respiratory cycle-related EEG changes in children with sleep-disordered breathing.

STUDY OBJECTIVES: To explore newly-identified respiratory cycle-related electroencephalographic changes (RCREC), which may represent microarousals, as correlates of neurobehavioral outcomes in children with sleep-disordered breathing (SDB). DESIGN: Retrospective. SETTING: University sleep laboratory. PARTICIPANTS: Ten research subjects, aged 6 to 10 years, with and without SDB. INTERVENTION: Polysomnography, Multiple Sleep Latency Tests, and tests of auditory attention before and after clinically-indicated tonsillectomy (n = 9) or hernia repair (n = 1, control). MEASUREMENTS: For the first 3 hours of nocturnal sleep, a computer algorithm quantified the degree to which delta, theta, and alpha electroencephalographic power varied within non-apneic respiratory cycles. Correlations between the RCREC and standard objective measures of SDB, sleepiness, and attention were explored. RESULTS: Five children had SDB (> 1 obstructive apnea per hour of sleep). Preoperative delta, theta, or alpha RCREC were statistically significant (P < .01) in all subjects except 1 without SDB and the 1 control. Theta RCREC correlated with rates of apneas and hypopneas (P = .01) and decreased after the apnea was treated. Postoperative changes in delta and theta RCREC predicted changes in Multiple Sleep Latency Test scores (rho = -0.84, P = .002; rho = -0.64, P = .05), whereas changes in rates of apneas and hypopneas did not (rho = -0.24, P = .50). Postoperative changes in attention tended to correlate with changes in delta RCREC (rho = -0.54, P = .11) more strongly than with changes in rates of apneic events (rho = -0.07, P = .84). CONCLUSIONS: The RCREC may reflect brief but numerous microarousals that could help to explain neurobehavioral consequences of SDB.

Algorithms↗

Polysomnography in children scheduled for adenotonsillectomy.

OBJECTIVE: Several studies suggest that a reliable diagnosis of childhood sleep-disordered breathing (SDB) requires polysomnography (PSG). We compared clinical and PSG-based diagnoses in children scheduled for adenotonsillectomy (AT). Parent responses on a validated Pediatric Sleep Questionnaire were used to determine which symptoms could help identify children with clinical diagnoses of SDB but normal PSG. STUDY DESIGN AND SETTING: Thirty-four children aged 5.0 to 12.9 years and scheduled for AT to treat clinically diagnosed sleep-disordered breathing underwent laboratory-based PSG. Results were scored by 3 different criteria: 1) >1 obstructive apnea (2 breaths or longer) per hour of sleep; 2) >5 apneas or hypopneas per hour of sleep; or 3) >1 apnea, hypopnea, or respiratory event-related arousal per hour of sleep. RESULTS: Depending on the criterion used, the PSG documented SDB from a minimum of 18/34 subjects (53%, for criterion I) to as many as 30/34 subjects (88%, for criterion III). Among symptoms studied, absence of daytime mouth breathing and habitual snoring were most helpful in identification of children who had no evidence of SDB on PSG, by criterion I (Chi-square, P < 0.05). The absence of other common symptoms, such as "loud snoring" or "trouble breathing" at night, were not helpful. CONCLUSION: Children with clinical diagnoses of SDB may not consistently meet PSG criteria for this disorder. Questions about daytime mouth breathing and habitual snoring might help clinicians recognize children who would not have SDB on objective testing. SIGNIFICANCE: Clinical identification of SDB confirmable on PSG could be improved. However, available outcome data do not yet clarify whether clinical or PSG criteria best identify children likely to suffer morbidity from SDB. EBM RATING: C.

Adenoidectomy↗

Cognitive executive dysfunction in children with mild sleep-disordered breathing.

In children, moderate or severe sleep-disordered breathing (SDB) may impair cognitive executive functions (EFs), including working memory, attention, and mental flexibility. The main objective of this study was to assess EFs in children with mild levels of SDB. Subjects for this descriptive study were 12 children (5 girls, 7 boys) aged 8.0 to 11.9 years (M = 9.0 +/- 0.85) participating in an ongoing study of the effects of adenotonsillectomy on behavior. Each subject had a nocturnal polysomnogram (PSG) and a multiple sleep latency test (MSLT). Mild SDB was considered present if the child's apnea/hypopnea index (AHI) was > or = 1 and < 10. Between MSLT nap attempts, each child completed standardized tests of EFs. The sample showed significant impairment of sustained attention and vigilance on a computerized continuous performance test. Children with low mental flexibility scores on the Children's Category Test (CCT) spent more time in stage 1 sleep (12.2% v. 9.5%, P = 0.028 on PSG) and showed a marginally higher arousal index (9.7 v. 6.5, P = 0.06 on PSG) than children with average or above-average CCT scores. AHI accounted for a significant proportion of the variance in CCT scores when 1 outlier was removed (N = 11, Rsq = 0.67, P = 0.002). Mild levels of SDB and associated sleep architecture disruptions may be associated with impairment of EFs in children.

Analysis of Variance↗

Tolerance of esophageal pressure monitoring during polysomnography in children.

OBJECTIVES: To assess tolerance of esophageal pressure monitoring (EPM) among 5- to 13-year-old children during research polysomnography at study entry and again 1 year later. DESIGN: Prospective, observational study. SETTING: University-based sleep laboratory. PARTICIPANTS: Children scheduled for adenotonsillectomy or hernia repair. INTERVENTIONS: None; all operations were performed for clinical indications only. RESULTS: Forty-two of 336 families approached about the study declined to participate mainly to avoid EPM. The EPM was usually the main concern for the 47 adenotonsillectomy and 7 hernia-repair patients and families who did participate. Among 54 enrolled subjects, 51 allowed attempts at insertion of the esophageal catheter, and insertion was successful in all cases; 38 tolerated EPM for at least 2 hours; 33 maintained EPM for the entire night; and 36 had repeat EPM 1 year later for at least 2 hours. Reasons for EPM failure included crying at insertion, vomiting, pain, and inadvertent catheter removal during sleep. The children who tolerated EPM for at least 2 hours did not differ from other subjects based on age, sex, presence of a disruptive behavior disorder, anxiety, tonsil size, history of tonsillitis, or body mass index (all P > .05). CONCLUSIONS: The EPM was well tolerated in most school-aged volunteers, but many families did not volunteer, and some children were not able to endure EPM for at least 2 hours. Although better success might be achieved in clinical settings if EPM is medically indicated and not part of voluntary research, EPM is still likely to create significant concern, for children and parents, that must be weighed against anticipated benefits.

Adenoidectomy↗

School performance, race, and other correlates of sleep-disordered breathing in children.

OBJECTIVES: Childhood sleep-disordered breathing (SDB) has been associated with poor school performance. Both problems are common among African-American (AA) children, but potential confounders such as low socioeconomic status (SES) and obesity have not been well studied. METHODS: Children in second and fifth grades at six urban elementary schools were evaluated by teachers' ratings and year-end reading and math assessments. Risk for SDB was assessed with the validated parental Pediatric Sleep Questionnaire, and SES by qualification for school lunch assistance. RESULTS: Among 146 children whose parents completed surveys, risk for SDB was associated with AA race, low SES, and poor teacher ratings (P<0.01), but not assessment scores (P>0.1). In multiple regression models, poor school performance was consistently and independently predicted by low SES (P<0.01) but not by AA race or SDB risk. Risk for SDB was associated with low SES before, but not after body mass index (BMI) was taken into account. CONCLUSIONS: The SDB symptoms, AA race, and low SES all vary to some extent with poor school performance, but the only consistent and independent covariate of performance is SES. Risk for SDB is associated with low SES, perhaps because of a third variable, namely high BMI.

Black People↗

Identification and evaluation of obstructive sleep apnea prior to adenotonsillectomy in children: a survey of practice patterns.

OBJECTIVES: Some data suggest that the clinical diagnosis of obstructive sleep apnea (OSA) in a child should be confirmed by polysomnography before adenotonsillectomy (AT), but otolaryngology literature generally does not agree and few studies have examined surgical practice patterns. METHODS: We mailed, to 603 members of two North American otolaryngology societies, surveys about children aged 5.0-12.9 years upon whom they performed ATs in the previous year. RESULTS: A total of 183 otolaryngologists estimated that they had performed 24,000 ATs. Reported major surgical indications, not mutually exclusive, included recurrent throat infections (for 42% of procedures), obstructed breathing of any type (59%), OSA (39%), poor school performance (17%), and poor attention (11%). Pre-operative evaluations included an office-based, sleep-related history in 93% of children, any objective testing for OSA in <10%, and laboratory-based polysomnography in <5%. Surgeons with academic affiliations, higher volumes of ATs, and pediatric specialization reported lower percentages of ATs performed for recurrent tonsillitis as opposed to other indications. CONCLUSIONS: As a common indication for AT, OSA now rivals recurrent throat infection. No more than 12% of school-aged children who undergo AT for OSA have polysomnography prior to the procedure. Indications for AT may depend, in part, on practice settings and otolaryngologists' backgrounds.

Adenoidectomy↗

Conduct problems and symptoms of sleep disorders in children.

OBJECTIVE: Conduct problems and hyperactivity are frequent among children referred for sleep-disordered breathing (SDB), restless legs syndrome, or periodic leg movements during sleep (PLMS), but children not referred to sleep centers have received little study. METHOD: Parents of children aged 2 to 14 years were surveyed at two general clinics between 1998 and 2000. A Pediatric Sleep Questionnaire generated validated scores for SDB and PLMS. The Conners Parent Rating Scale (CPRS-48) produced an age- and sex-adjusted Conduct Problem Index (CPI) and Hyperactivity Index. RESULTS: Parents of about 1,400 children were approached; those of 872 (62%) completed the surveys. Bullying and other specific aggressive behaviors were generally two to three times more frequent among 114 children at high risk for SDB than among the remaining children. An association between high CPI and SDB scores (p <.0001) retained significance after adjustment for sleepiness, high Hyperactivity Index, stimulant use, or PLMS scores. Analogous results were obtained for the association between high CPI and PLMS scores. CONCLUSIONS: Conduct problems were associated with symptoms of SDB, restless legs syndrome, and PLMS. Although these results cannot prove a cause-and-effect relationship, assessment for sleep disorders may provide a new treatment opportunity for some aggressive children.

Child↗