Bedtime routines for young children: a dose-dependent association with sleep outcomes.

BACKGROUND: Establishment of a consistent bedtime routine (the activities that occur right before lights out) is often recommended as part of healthy sleep habits. However, no studies have investigated the dose-dependent association of a bedtime routine with sleep outcomes, especially in young children for whom they are particularly recommended. Thus, the aim of this study was to examine the associations of a consistent bedtime routine with sleep outcomes in young children (ages 0 through 5 y) in a large global sample and assess whether there is a dose-dependent relationship between the frequency of a bedtime routine both concurrently and retrospectively with sleep outcomes. PARTICIPANTS: Mothers of 10,085 children (Australia-New Zealand, Canada, China, Hong Kong, India, Japan, Korea, Malaysia, Philippines, Singapore, Thailand, United Kingdom, United States) completed the Brief Infant/Child Sleep Questionnaire. RESULTS: A consistent bedtime routine was associated with better sleep outcomes, including earlier bedtimes, shorter sleep onset latency, reduced night wakings, and increased sleep duration. Decreased parent-perceived sleep problems and daytime behavior problems were also related to institution of a regular bedtime routine. Furthermore, there was a dose-dependent relationship, with better outcomes associated with increased "doses" of having a bedtime routine, both currently and retrospectively, and was found within both predominantly Asian and predominantly Caucasian cultural regions. CONCLUSIONS: These results indicate that having a regular nightly bedtime routine is associated with improved sleep in young children, and suggests that the more consistently a bedtime routine is instituted and the younger started the better.

Cross-cultural comparison of maternal sleep.

BACKGROUND: To characterize cross-cultural sleep patterns and sleep problems in a large sample of mothers of children (ages birth to 6 years) in multiple predominantly Asian and predominantly Caucasian countries. METHODS: Mothers of 10,085 young children (predominantly Asian countries/regions: China, Hong Kong, India, Korea, Japan, Malaysia, Philippines, Singapore, Thailand; predominantly Caucasian countries: Australia, Canada, New Zealand, United Kingdom, United States) completed an internet-based expanded version of the Pittsburgh Sleep Quality Index. RESULTS: Mothers in predominantly Asian countries/regions had later bedtimes, decreased number and duration of night wakings, more nighttime sleep, and more total sleep than mothers from predominantly Caucasian countries, P < 0.001. More than half (54.7%) of mothers reported having poor sleep, ranging from 50.9% of mothers in Malaysia to 77.8% of mothers in Japan. Sleep disturbance symptoms were quite common, especially symptoms related to insomnia, and were more likely to be reported by mothers in predominantly Caucasian countries. However, psychosocial factors, including having children of a younger age, being unemployed, and having a lower education level were the best predictors of poor sleep, whereas culture was not a significant predictor. CONCLUSIONS: Overall, mothers in predominantly Asian countries/regions reported later bedtimes but sleeping better and longer than mothers from predominantly Caucasian countries, which is dissimilar to cross-cultural findings of young children. Psychosocial factors were found to be the best predictors of poor sleep, irrespective of culture. Further studies are needed to understand the impact of these findings.

Prospective multinational study of pertussis infection in hospitalized infants and their household contacts.

BACKGROUND: Increased incidence of pertussis has been noted among infants too young to be immunized. We studied the disease burden of pertussis in pediatric intensive care units and the source of infection in several Asian, European and Latin American countries. METHODS: The study was conducted in 7 countries from September 2001 to January 2004. Children <1 year of age were enrolled from pediatric intensive care units (PICU) and pediatric wards if they presented with respiratory failure, apnea, bradycardia, or cough accompanied by paroxysms, vomiting, whoop or cyanosis. Household members of pertussis-positive index cases were asked to answer a questionnaire and provide diagnostic specimens. RESULTS: Pertussis was confirmed in 99 infants (12%) of 823 infants included in the analysis: 10 of 90 (11%) in Brazil, 9 of 88 (10%) in Costa Rica, 11 of 145 (8%) in Germany, 13 of 147 (9%) in Singapore, 29 of 67 (43%) in Spain, 2 of 86 (2%) in Taiwan and 25 of 200 (13%) in Uruguay. However, sensitivity analysis indicated that these figures were conservative. The mean (+/- SD) average age of infection was 2.6 +/- 2.2 months. Pertussis was found among 96 of 269 (36%) of household contacts investigated. At least one household contact was identified as the source of infection in 24 of 88 (27%) of the PICU cases and mothers were identified as being the most frequent source of infection. CONCLUSION: Although regional differences exist, severe pertussis represents a considerable global disease burden. Since most infants are infected before vaccination and concomitant protection is completed, household contacts should be targeted for booster vaccination to reduce the pertussis reservoir.