Seasonality of the incidence of bronchiolitis in infants — Brazil, 2016-2022: An interrupted time-series analysis / Sazonalidade da incidência de bronquiolite em lactentes — Brasil, 2016-2022: Uma análise de série temporal interrompida

ABSTRACT Objective: To evaluate the seasonality of acute bronchiolitis in Brazil during the 2020-2022 season and compare it with the previous seasons. Methods: Data from the incidence of hospitalizations due to acute bronchiolitis in infants <1 year of age were obtained from the Department of Informatics of the Brazilian Public Health database for the period between 2016 and 2022. These data were also analyzed by macro-regions of Brazil (North, Northeast, Southeast, South, and Midwest). To describe seasonal and trend characteristics over time, we used the Seasonal Autoregressive Integrated Moving Averages Model. Results: Compared to the pre-COVID-19 period, the incidence of hospitalizations related to acute bronchiolitis decreased by 97% during non-pharmacological interventions (March 2020 - August 2021) but increased by 95% after non-pharmacological interventions relaxation (September 2021 - December 2022), resulting in a 16% overall increase. During the pre-COVID-19 period, hospitalizations for acute bronchiolitis followed a seasonal pattern, which was disrupted in 2020-2021 but recovered in 2022, with a peak occurring in May, approximately 4% higher than the pre-COVID-19 peak. Conclusions: This study underscores the significant influence of COVID-19 interventions on acute bronchiolitis hospitalizations in Brazil. The restoration of a seasonal pattern in 2022 highlights the interplay between public health measures and respiratory illness dynamics in young children.

RESUMO Objetivo: Avaliar a sazonalidade da bronquiolite aguda no Brasil durante a temporada 2020-2022 e compará-la com a das temporadas anteriores. Métodos: Os dados de incidência de internações por bronquiolite aguda em lactentes <1 ano de idade foram obtidos do Departamento de Informática da base de dados da Saúde Pública Brasileira para o período entre 2016 e 2022. Esses dados também foram analisados por macrorregiões do Brasil (Norte, Nordeste, Sudeste, Sul e Centro-Oeste). Para descrever características sazonais e de tendência ao longo do tempo, utilizamos o Modelo de Médias Móveis Integradas Autorregressivas Sazonais. Resultados: Em comparação com o período pré-COVID-19, a incidência de hospitalizações relacionadas com bronquiolite aguda diminuiu 97% durante as intervenções não farmacológicas (março de 2020 - agosto de 2021), mas aumentou 95% após a flexibilização das intervenções não farmacológicas (setembro de 2021 - dezembro de 2022), resultando no aumento geral de 16%. Durante o período pré-COVID-19, as hospitalizações por bronquiolite aguda seguiram um padrão sazonal, que foi interrompido em 2020-2021, mas recuperaram-se em 2022, com um pico ocorrido em maio, aproximadamente 4% superior ao pico pré-COVID-19. Conclusões: Este estudo ressalta a influência significativa das intervenções contra a COVID-19 nas hospitalizações por bronquiolite aguda no Brasil. A restauração de um padrão sazonal em 2022 sublinha a interação entre as medidas de saúde pública e a dinâmica das doenças respiratórias em crianças pequenas.

Seasonality of the incidence of bronchiolitis in infants - Brazil, 2016-2022: An interrupted time-series analysis.

OBJECTIVE: To evaluate the seasonality of acute bronchiolitis in Brazil during the 2020-2022 season and compare it with the previous seasons. METHODS: Data from the incidence of hospitalizations due to acute bronchiolitis in infants <1 year of age were obtained from the Department of Informatics of the Brazilian Public Health database for the period between 2016 and 2022. These data were also analyzed by macro-regions of Brazil (North, Northeast, Southeast, South, and Midwest). To describe seasonal and trend characteristics over time, we used the Seasonal Autoregressive Integrated Moving Averages Model. RESULTS: Compared to the pre-COVID-19 period, the incidence of hospitalizations related to acute bronchiolitis decreased by 97% during non-pharmacological interventions (March 2020 - August 2021) but increased by 95% after non-pharmacological interventions relaxation (September 2021 - December 2022), resulting in a 16% overall increase. During the pre-COVID-19 period, hospitalizations for acute bronchiolitis followed a seasonal pattern, which was disrupted in 2020-2021 but recovered in 2022, with a peak occurring in May, approximately 4% higher than the pre-COVID-19 peak. CONCLUSIONS: This study underscores the significant influence of COVID-19 interventions on acute bronchiolitis hospitalizations in Brazil. The restoration of a seasonal pattern in 2022 highlights the interplay between public health measures and respiratory illness dynamics in young children.

Benzbromarone as adjuvant therapy for cystic fibrosis lung disease: a pilot clinical trial.

OBJECTIVE: Cystic fibrosis (CF) affects multiple organs, the most severe consequences being observed in the lungs. Despite significant progress in developing CF transmembrane conductance regulator-specific treatments for CF lung disease, exploring alternative CF-targeted medications seems reasonable. We sought to evaluate the potential beneficial effects of oral benzbromarone as an adjuvant therapy in CF patients with reduced lung function. METHODS: This was a prospective open-label pilot study of oral benzbromarone (100 mg/day) administered once daily for 90 days. Patients were followed at a tertiary referral center in southern Brazil. Safety was assessed by the number of reported adverse events. Secondary objectives included percent predicted FEV1 (FEV1%) and pulmonary exacerbations. RESULTS: Ten patients were enrolled. Benzbromarone was found to be safe, with no serious drug-related adverse events. Eight patients completed the study; the median relative change in FEV1% tended to increase during the treatment, showing an 8% increase from baseline at the final visit. However, a nonparametric test showed that the change was not significant (p = 0.06). Of a total of ten patients, only one experienced at least one pulmonary exacerbation during the study. CONCLUSIONS: Oral benzbromarone appears to be safe, and improved FEV1% has been observed in patients with CF. Further assessment in larger trials is warranted to elucidate whether oral benzbromarone can be a potential adjuvant therapy for CF.

Benzbromarone as adjuvant therapy for cystic fibrosis lung disease: a pilot clinical trial

ABSTRACT Objective: Cystic fibrosis (CF) affects multiple organs, the most severe consequences being observed in the lungs. Despite significant progress in developing CF transmembrane conductance regulator-specific treatments for CF lung disease, exploring alternative CF-targeted medications seems reasonable. We sought to evaluate the potential beneficial effects of oral benzbromarone as an adjuvant therapy in CF patients with reduced lung function. Methods: This was a prospective open-label pilot study of oral benzbromarone (100 mg/day) administered once daily for 90 days. Patients were followed at a tertiary referral center in southern Brazil. Safety was assessed by the number of reported adverse events. Secondary objectives included percent predicted FEV1 (FEV1%) and pulmonary exacerbations. Results: Ten patients were enrolled. Benzbromarone was found to be safe, with no serious drug-related adverse events. Eight patients completed the study; the median relative change in FEV1% tended to increase during the treatment, showing an 8% increase from baseline at the final visit. However, a nonparametric test showed that the change was not significant (p = 0.06). Of a total of ten patients, only one experienced at least one pulmonary exacerbation during the study. Conclusions: Oral benzbromarone appears to be safe, and improved FEV1% has been observed in patients with CF. Further assessment in larger trials is warranted to elucidate whether oral benzbromarone can be a potential adjuvant therapy for CF.

Sleep and quality of life characteristics in a pediatric population with chronic obstructive respiratory diseases.

PURPOSE: To describe sleep and quality of life of pediatric patients with chronic obstructive respiratory diseases and to ascertain whether or not sleep quality correlates with quality of life in this population. METHODS: Participants aged 5 to 18 years with cystic fibrosis (CF), severe asthma, or postinfectious bronchiolitis obliterans (PIBO) receiving regular follow-up at a pediatric respiratory medicine center were recruited. Two questionnaires were used: the Brazilian version of the Sleep Disturbance Scale for Children (SDSC) and the Pediatric Quality of Life Inventory (Peds-QL). RESULTS: A total of 46 individuals were included: 30 with CF, 9 with severe asthma, and 7 with PIBO. Almost two-thirds of the patients and their parents or guardians scored at least 39 points on the SDSC, suggesting poor sleep quality. Significantly higher overall median scores were observed in those with severe asthma. Patients and their parents or guardians scored a median of 77 and 80 points respectively on the Peds-QL, with parents of patients with CF scoring higher than any other group. There was a moderate inverse correlation between sleep disorders and quality of life (r = - 0.532 for patients and r = - 0.606 for parents; p < 0.001). CONCLUSION: Children and adolescents with chronic obstructive respiratory diseases experience impairment in their sleep quality and quality of life. Sleep disorders and quality of life have a moderate negative correlation.

Impact of nonpharmacological COVID-19 interventions in hospitalizations for childhood pneumonia in Brazil.

BACKGROUND AND OBJECTIVE: The knowledge about the impact of the nonpharmacological measures to control the COVID-19 pandemic can give insight into ways in which they can also be applied for other respiratory diseases. To assess the impact of containment measures of the COVID-19 pandemic on pneumonia hospitalizations in children from 0 to 14 years of age in Brazil. METHODS: Data from hospital admissions for pneumonia were obtained from the Department of Informatics of Brazilian Public Health System database in the period of 2015-2020 and analyzed by macroregions and age groups. To evaluate the effect of containment measures, on the incidence of pneumonia, the absolute reduction and relative reduction were calculated by analyzing the subsets 2015-2019 vs. 2020. RESULTS: Comparing the subsets of April-August 2015-2019 vs. April-August 2020 for Brazil (total), there was an significant reduction in the average incidence of hospitalizations, with numbers ranging from -82% [IRR 0.17 (0.14-0.21)] for <4 years (prepandemic 741.8/100,000 vs. pandemic 132.7/100.000), -83% [IRR 0.17 (0.10-0.27)] for 5-9 years (prepandemic 113.6/100,000 vs. pandemic 19.6/100.000), -77% [IRR 0.23 (0.11-0.46)] for 10-14 (prepandemic 42.0/100,000 vs. pandemic 9.8/100.000) and -82% [IRR 0.18 (0.15-0.21)] for all children ≤14 years (prepandemic 897.4/100,000 vs. pandemic 162.1/100.000). CONCLUSION: We found a significant decrease in cases of all cause pneumonia in children under 14 years and especially in the age group <9 years during the COVID-19 pandemic, which may be associated with the nonpharmacological measures applied to control the SARS-CoV-2.

Early Impact of Social Distancing in Response to Coronavirus Disease 2019 on Hospitalizations for Acute Bronchiolitis in Infants in Brazil.

BACKGROUND: Interventions to tackle the coronavirus disease 2019 (COVID-19) pandemic may affect the burden of other respiratory diseases. Considering the repercussions of these unique social experiences to infant health, this study aims to assess the early impact of social distancing due to the COVID-19 pandemic in hospital admissions for acute bronchiolitis. METHODS: Data from hospitalizations of acute bronchiolitis in infants <1 year of age were obtained from the Department of Informatics of the Brazilian Public Health database for the period between 2016 and 2020. These data were also analyzed by macroregions of Brazil (North, Northeast, Southeast, South, and Midwest). To evaluate the effect of social distancing strategy on the incidence of acute bronchiolitis, the absolute and relative reductions were calculated by analyzing the yearly subsets of 2016 vs 2020, 2017 vs 2020, 2018 vs 2020, and 2019 vs 2020. RESULTS: There was a significant reduction in all comparisons, ranging from -78% (incidence rate ratio [IRR], 0.22 [95% confidence interval {CI}, .20-.24]) in 2016 vs 2020 to -85% (IRR, 0.15 [95% CI, .13-.16]) in 2019 vs 2020, for the data from Brazil. For analyses by macroregions, the reduction varied from -58% (IRR, 0.41 [95% CI, .37-.45]) in the Midwest in 2016 vs 2020 to -93% (IRR, 0.07 [95% CI, .06-.08]) in the South in 2019 vs 2020. CONCLUSIONS: There was a significant reduction in hospitalization for acute bronchiolitis in children <1 year old in Brazil, on the order of >70% for most analysis. Our data suggest an important impact of social distancing on reducing the transmission of viruses related to acute bronchiolitis. Such knowledge may guide strategies for prevention of viral spread.

Validation of the Brazilian version of the Pediatric Obstructive Sleep Apnea Screening Tool questionnaire / Validação da versão brasileira do questionário Pediatric Obstructive Sleep Apnea Screening Tool

Abstract Objective: To validate the Pediatric Obstructive Sleep Apnea Screening tool for use in Brazil. Materials and methods: The Brazilian version of this questionnaire, originally validated and tested in the United States, was developed as follows: (a) translation; (b) back-translation; (c) completion of the final version; (d) pre-testing. The questionnaire was applied prior to polysomnography to children aged 3-9 years from October 2015 to October 2016, and its psychometric properties (i.e., validity and reliability) were evaluated. The accuracy was assessed from comparisons between polysomnographic results and corresponding questionnaire scores. Results: Sixty patients were enrolled, and based on polysomnographic findings, 48% patients had normal apnea-hypopnea index, while the remaining 52% met the criteria for obstructive sleep apnea. Minimum O2 saturation level was significantly lower among obstructive sleep apnea children (p = 0.021). Satisfactory concordance was found between individual apnea-hypopnea index and questionnaire scores. Bland-Altman plot-derived bias was 0.1 for the difference between measures, with 5.34 (95% CI: 4.14-6.55) and −5.19 (95%CI: −6.39 to −3.98) for the upper and lower agreement range. Internal consistency derived from Cronbach's alpha was 0.84 (95%CI: 0.78-0.90). Conclusion: The questionnaire was translated to and validated into Brazilian-Portuguese version, and showed good reliability and concordance with apnea-hypopnea index. This questionnaire offers a reliable screening option for sleep-disordered breathing in children.

Resumo Objetivo: Validar o questionário Pediatric Obstructive Sleep Apnea Screening Tool para o seu uso no Brasil. Materiais e métodos: A versão brasileira desse questionário, originalmente validado e testado nos Estados Unidos, foi desenvolvida a partir das seguintes etapas: a) tradução; b) retrotradução; c) conclusão da versão final; d) pré-teste. O questionário foi aplicado previamente ao início da polissonografia em crianças de 3 a 9 anos incluídas no estudo de outubro de 2015 a outubro de 2016. As propriedades psicométricas avaliadas foram validade e confiabilidade. A acurácia foi avaliada pela comparação entre os resultados da polissonografia com o escore do questionário. Resultados: Foram incluídos no estudo 60 pacientes. Conforme a polissonografia, 48% dos pacientes apresentaram índices de apneia e hipopneia normais e 51% apresentaram resultados alterados. A SpO2 mínima foi significativamente menor (p = 0,021) nas crianças com diagnóstico de síndrome de apneia obstrutiva do sono. O índice de apneia e hipopneia apresentou concordância satisfatória com os resultados do questionário. O viés médio de Bland-Altman foi de 0,1 para a diferença entre as medidas, com um limite superior de 5,34 (IC95%4,14 a 6,55) e um limite inferior de -5,19 (IC95%-6,39 a -3,98). A consistência interna do questionário avaliada pelo α de Cronbach foi de 0,84 (IC95%0,78 a 0,90). Conclusão: O questionário foi traduzido e validado adequadamente para a versão em português brasileiro, apresentando boa confiabilidade e concordância com o índice de apneia e hipopneia. Esse questionário oferece uma opção confiável de triagem de distúrbios respiratórios do sono em crianças.

Sleep-disordered breathing in cystic fibrosis pediatric subjects.

OBJECTIVES: To describe the frequency of sleep-disordered breathing (SDB) in pediatric cystic fibrosis (CF) and to study associations between polysomnographic respiratory parameters and available clinical information. METHODS: This was a retrospective, cross-sectional study. The sample data were obtained from information recorded on patient charts in 2015 and 2016. The study included all individuals with CF aged from 2 to 20 years for whom records were available for polysomnography performed within the previous two years. RESULTS: Sixteen individuals with CF (mean age 11 ± 5.6 years old) were included. Polysomnographic respiratory parameter abnormalities were defined as an apnea-hypopnea index (AHI) exceeding one event per hour of sleep or an oxyhemoglobin saturation (SpO2) nadir below 90%; observed in 10 subjects (62.5%). Forced expiratory volume in first second (FEV1) was correlated (r=0.602, p=0.023) with mean sleep SpO2. FEV1 was also negatively correlated with sleep peak end-tidal carbon dioxide (EtpCO2) (r=-0.645, p=0.024). Additionally, chronic airway colonization by Pseudomonas aeruginosa was associated with mean EtpCO2 in non-REM sleep (p=0.024). DISCUSSION: SDB was frequently observed in this sample of children with CF. There was an association between CF respiratory disease progression markers and sleep breathing parameters in children. Sleep studies appear to be an important tool for assessment of the respiratory status of these individuals with CF, although further studies are needed, especially with carbon dioxide sleep analysis.

Validation of the Brazilian version of the Pediatric Obstructive Sleep Apnea Screening Tool questionnaire.

OBJECTIVE: To validate the Pediatric Obstructive Sleep Apnea Screening tool for use in Brazil. MATERIALS AND METHODS: The Brazilian version of this questionnaire, originally validated and tested in the United States, was developed as follows: (a) translation; (b) back-translation; (c) completion of the final version; (d) pre-testing. The questionnaire was applied prior to polysomnography to children aged 3-9 years from October 2015 to October 2016, and its psychometric properties (i.e., validity and reliability) were evaluated. The accuracy was assessed from comparisons between polysomnographic results and corresponding questionnaire scores. RESULTS: Sixty patients were enrolled, and based on polysomnographic findings, 48% patients had normal apnea-hypopnea index, while the remaining 52% met the criteria for obstructive sleep apnea. Minimum O2 saturation level was significantly lower among obstructive sleep apnea children (p=0.021). Satisfactory concordance was found between individual apnea-hypopnea index and questionnaire scores. Bland-Altman plot-derived bias was 0.1 for the difference between measures, with 5.34 (95% CI: 4.14-6.55) and -5.19 (95%CI: -6.39 to -3.98) for the upper and lower agreement range. Internal consistency derived from Cronbach's alpha was 0.84 (95%CI: 0.78-0.90). CONCLUSION: The questionnaire was translated to and validated into Brazilian-Portuguese version, and showed good reliability and concordance with apnea-hypopnea index. This questionnaire offers a reliable screening option for sleep-disordered breathing in children.

Comparação entre a evolução de pré-escolares com fibrose cística identificados por triagem neonatal ou por sintomatologia clínica / Comparison between the outcome of preschool children with cystic fibrosis identified by newborn screening or by clinical symptoms

OBJETIVOS: Comparar dados clínicos, laboratoriais e espirométricos de pacientes pré-escolares (idade entre três e seis anos) com fibrose cística, identificados pela alteração do tripsinogênio imunorreativo no teste de triagem neonatal (grupo IRT) com os dados de pacientes cuja suspeita diagnóstica ocorreu a partir de sinais e sintomas clínicos (grupo DC). MÉTODOS: Estudo do tipo coorte retrospectiva, com amostra obtida a partir dos prontuários dos pacientes que faziam acompanhamento ambulatorial especializado e multidisciplinar. Todas as crianças incluídas tinham diagnóstico confirmado de fibrose cística por teste de eletrólitos no suor e/ou sequenciamento genético. Como variáveis incluíram-se sexo, peso, altura, índice de massa corporal, número de internações por ano, colonização por Pseudomonas aeruginosa, presença de insuficiência pancreática e escore de Shwachman. Este escore abrange quatro domínios: atividade geral, nutrição, exame radiológico e avaliação física, cada um pontuado entre 5 e 25 pontos, sendo que o escore ≤40 pontos indica estado grave e ≥86 pontos excelente estado. Para comparação da função pulmonar utilizaram-se os dados da última espirometria realizada antes dos seis anos de idade. Os desfechos foram comparados por qui-quadrado ou teste t de Student, com limite de significância de 0,05. RESULTADOS: Foram incluídos no estudo 24 pacientes, sete no grupo IRT e 17 no grupo DC. As crianças do grupo IRT iniciaram acompanhamento com média de idade de 1,51±2,04 meses e as do grupo DC com 3,77±1,80 meses (p=0,014). A média do escore de Shwachman foi 94,40±2,19 nos pacientes do grupo IRT vs. 87,67±8,00 no grupo DC (p=0,018). A média do escore Z para o índice de massa corporal foi 0,95±1,02 no grupo IRT vs. 0,51±1,05 no grupo DC (p=0,051). Foram encontrados valores ligeiramente superiores nas variáveis espirométricas no grupo IRT, sem diferença estatisticamente significativa entre os grupos. CONCLUSÕES: Os resultados sugerem que os pacientes diagnosticados com fibrose cística a partir da suspeita pelo teste de triagem neonatal beneficiaram-se de uma intervenção precoce, podendo iniciar os testes de função pulmonar e receber tratamento e orientações mais cedo. A avaliação de parâmetros clínicos com o escore de Shwachman mostrou que os benefícios puderam ser observados já na idade pré-escolar.

AIMS: To compare clinical, laboratory and spirometric parameters of preschoolers (ages from three to six years old) with cystic fibrosis identified by abnormal newborn screening test (NS group), with data of patients whose diagnostic suspicion arose from characteristic clinical signs and symptoms (CS group). METHODS: Retrospective cohort study, with a sample obtained from the medical charts of patients who received specialized and multidisciplinary outpatient follow-up. All the included children had a confirmed diagnosis of cystic fibrosis by sweat electrolyte testing and/ or genetic sequencing. Variables included sex, weight, height, body mass index, number of hospitalizations per year, Pseudomonas aeruginosa colonization, presence of pancreatic insufficiency and Shwachman score, which covers four domains: general activity, nutrition, radiological examination and physical evaluation, each one scored between 5 and 25 points. A total score ≤40 points indicates severe state, and ≥86 points indicates excellent state. For comparison of pulmonary function, data from the last spirometry performed before the age of six years were used. Outcomes were compared by chi-square or Student's t test, with a significance limit of 0.05. RESULTS: Twenty-four patients were included in the study, seven children in the NS group and 17 children in the CS group. The children of the NS group started follow-up with a mean age of 1.51±2.04 months, and those of the CS group started with 3.77±1.80 months (p=0.014). The mean Shwachman score was 94.40±2.19 in the NS vs. 87.67±8.00 in the CS group (p=0.018). The mean Z score for body mass index was 0.95±1.02 in the NS group vs. 0.51±1.05 in the CS group (p=0.051). Spirometric variables had slightly higher values in the NS group, with no statistically significant difference between groups. CONCLUSIONS: The results suggest that those patients diagnosed with cystic fibrosis from the neonatal screening test suspicion benefited from an early intervention, being able to initiate pulmonary function tests and receive treatment and counseling earlier. Evaluation of clinical parameters with the Shwachman score showed that benefits could be already observed at the preschool age.

Early impact of universal varicella vaccination on childhood varicella and herpes zoster hospitalizations in Brazil.

INTRODUCTION: The Brazilian childhood National Immunization Program (NIP) introduced live and attenuated varicella vaccination in a single dose, combined as tetraviral vaccine, at 15 months of age in the whole country, during September to December of 2013. The aim of this study was to report trends in incidence of childhood hospital admissions related to varicella and zoster in Brazil from 2003 to 2016, including the first three years after vaccine introduction. METHODS: The number and incidence of hospital admission in patients aged less than 20 years in Brazilian public health system with an admission diagnosis of varicella and zoster from 2003 to 2016 were analyzed and pre (2003-2013) and post-vaccination periods (2014-2016) were compared. The data were obtained from DATASUS, a Brazilian government's open-access public health database system, and analyzed adjusting for secular trend and seasonality if a statistically significant change was found. RESULTS: During the study period, 69,791 admissions due to varicella and herpes zoster occurred in the children younger than 20 years. After adjusting for seasonality, the incidence of hospitalizations decreased from 27.33 to 14.33 per 100000 per year, which corresponds to a reduction of 47.6% (95% confidence interval 18.19-77.04%, p < 0.001) in the vaccinated age group (1-4 years) in 2014-2016 compared to pre-vaccination period. The changes were not significant in the unvaccinated age groups. CONCLUSION: The hospitalizations due to varicella and herpes zoster were decreased by half early after the introduction of a single dose of tetraviral vaccine in NIP in the vaccinated children. Further studies may assess duration and intensity of this effect, as well as the indirect effect in the unvaccinated age groups.

Repeating administration of Epworth Sleepiness Scale is clinically useful.

PURPOSE: We aimed to verify whether it is clinically useful to repeat the Epworth Sleepiness Scale (ESS) in individuals with suspected sleep-disordered breathing (SDB). METHODS: In this cross-sectional, prospective study, results of the repeated administration of the ESS were analyzed. In 929 consecutive patients, ESS was obtained as usual in the laboratory routine, immediately before the sleep study (ESS1) and was repeated in the morning, after the polysomnography (ESS2). ROC curve, classical psychometry, and item response theory (IRT) Rasch analysis were used to assess measurement properties of ESS. RESULTS: The ESS1 score was (mean ± SD), 11 ± 5.1, and the ESS2, 13 ± 4.7 (p < 0.001). Change in ESS score is explained in multivariate analysis by age, but not by gender, educational level, change in Stanford Sleepiness Scale, symptoms of sleep disorder, or polysomnography results. Accuracy of an ESS score >10 to predict apnea-hypopnea index ≥5 increased from 56% (ESS1) to 72% (ESS2). IRT psychometric properties (unidimensionality, invariance, local independence) were maintained in ESS2. CONCLUSIONS: Repeating the administration of the Epworth Sleepiness Scale in a clinical setting increases its score and diagnostic accuracy and correlation with SDB variables, without changing the psychometric properties of the scale. This experiment indicates the clinical usefulness of repeating the ESS. The scale can be repeated at a negligible cost, before dismissing individual patients on the basis of a low ESS score, discontinuing a potentially lifesaving diagnostic and therapeutic process.

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

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 (alpha = 0.7); POLYSOMNOGRAPHY (alpha = 0.68); and COMPLAINTS (alpha = 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 (beta = -0.173, p = 0.003), and the AHI-N2 correlated significantly with COMPLAINTS (beta = -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.