Sleep disruption in caregivers of pediatric stem cell recipients

Parents/caregivers of hospitalized patients are at risk of sleep disruption. We performed a cross‐sectional quantitative and qualitative evaluation of sleep in parents/caregivers of children undergoing hematopoietic stem cell transplant (HSCT; n = 17). Additionally, we explored the frequency of room entries for hospitalized patients undergoing HSCT (n = 189 nights). Twelve caregivers (71%) demonstrated significant sleep disturbance, 12 (71%) described sleep quality as poor, 15 (88%) averaged < 6 hours of sleep per night, 14 (82%) awakened at least four times per night. Patient rooms were entered a median of 12 times per night (interquartile range 10–15). Intervention studies to improve caregiver sleep during hospitalization are needed.     

Sleep patterns of urban school-going adolescents

OBJECTIVE: To analyze the variance in sleep habits of adolescents of different high school Grades in urban India. DESIGN: Cross-sectional questionnaire-based study. SETTING: Community based school survey in an urban setting. SUBJECTS: School going adolescents from 9th to 12th Grades. METHODS: A total of 1,920 adolescents aged 12-18 years were included. The questionnaire contained questions related to sleep habits. Each question was explained to the participants and their responses were noted. Outcome parameters were total sleep time in a day, time to go to bed and wake up-time, sleep latency, nocturnal awakenings (duration, frequency per night and nights per week), wake-time after sleep onset, wake time after sleep offset, sleep efficiency, quality of sleep, daytime napping (duration and frequency), and sleepiness during the day. RESULTS: Mean age of the adolescents included in this study was 15.1 years and mean total sleep time was 7.8 hr/day. Adolescents of higher Grades had lesser total sleep time (9th=8 hours; 10th=7.7 hours; 11th=7.9 hours; 12th=7.6 hours; P=0.001), and more frequent nocturnal awakenings (9th=35.9%; 10th=44.7%; 11th=40.3%; 12th=28.3%; P=0.001). Daytime leg pain ( 9th=14.4%; 10th=18.4%; 11th=6.1%; 12th= 21.8%; P=0.01), daytime napping (9th=47.6%; 10th=50.4%; 11th=61.8%; 12th=69.8%; P=0.001), and daytime sleepiness (9th=37.2%; 10th=39.1%; 11th=39.7%; 12th=54.2%; P=0.001) increased progressively among higher Grades. Adolescents in higher Grades were more prone to not follow their weekly schedule on week-ends (P= 0.001). Sleep debt of approximately one hour per day was seen in all adolescents, and progressed with higher Grades. CONCLUSION: Adolescents of higher Grades had lesser sleep time, and frequent awakenings; suffered daytime leg pain, and felt sleepy during the day. These factors suggest increasing sleep deprivation among higher Graders.     

Double trouble? The effects of sleep deprivation and chronotype on adolescent affect

Background: Two understudied risk factors that have been linked to emotional difficulties in adolescence are chronotype and sleep deprivation. This study extended past research by using an experimental design to investigate the role of sleep deprivation and chronotype on emotion in adolescents. It was hypothesized that sleep deprivation and an evening chronotype would be associated with decreased positive affect (PA), increased negative affect (NA), and lower positivity ratios. Methods: Forty‐seven healthy adolescents (aged 10–15 for girls, 11–16 for boys) participated in a sleep deprivation and a rested condition. A subsample of 24 adolescents was selected on the basis of extreme morningness or eveningness scores (based on outer quartiles of scores on the Children’s Morningness‐Eveningness Preferences Scale). PA and NA were measured using the Positive and Negative Affect Schedule for Children, and positivity ratios were calculated by dividing PA by NA. Results: Participants reported less positive affect and lower positivity ratios when sleep deprived, relative to when rested. Evening chronotypes reported less positive affect and lower positivity ratios than morning chronotypes in both rested and sleep deprivation conditions. Conclusions: These findings extend previous research by suggesting that adolescents are adversely impacted by sleep deprivation, and that an evening chronotype might serve as a useful marker of emotional vulnerability. Early intervention and prevention strategies can focus on improving sleep and on using chronotherapy principles to reduce eveningness.     

Infant and toddler sleep in Australia and New Zealand

Aims: To characterize sleep patterns and sleep problems in a large sample of young children (birth to 36 months) in Australia (AU) and New Zealand (NZ). Methods: Parents and caregivers of 2154 infants and toddlers in AU and NZ completed an expanded version of the Brief Infant Sleep Questionnaire. Results: Overall, young children in AU and NZ go to bed relatively early (19:35), awaken on average 1.08 times per night for an average of 23 min, have a low likelihood of bed‐sharing with parents (7.2%) and obtain an average of 13.24 h total sleep. However, a significant percentage of parents perceive that their child has a sleep problem (30.69%). Sleep patterns in these children demonstrate clear developmental changes, including a decrease in daytime sleep and total sleep time, as well as consolidation of sleep during the night (decrease in night wakings and nocturnal wakefulness). Parents in AU and NZ are also highly likely to encourage independence and self‐soothing, especially after the age of 3 months. Conclusions: These findings provide parents and professionals reference data for assessing sleep in young children, as well as common parenting practices related to sleep behaviours.     

Sleep Characteristics in Mothers of Children With Developmental Disabilities

Impaired sleep can contribute to conditions such as cardiometabolic disorders, depression, and decreased immune function. Mothers of children with developmental disabilities (DDs) may be at greater risk for impaired sleep due to the sleep problems of their children. This cross-sectional study described the self-reported sleep characteristics of mothers of children (ages 6-12) with DDs by using a sleep diary and the Pittsburgh Sleep Quality Index (PSQI) as quantitative and qualitative measures of sleep in these mothers. The Consensus Sleep Diary was modified to ascertain how the child's sleep and needs for care during the night impacted the mother's sleep. The results showed that mothers had short sleep duration (nearly 40% slept <7 hours per night), woke up an average of 2.2 times per night (most commonly due to caregiving needs of children), and had poor sleep quality (mean PSQI global score of 7.9 [SD=4.8]). The sleep problems of children with DDs may influence mothers’ sleep.     

Siesta and sleep patterns in a sample of adolescents in Greece

Background: Sleep behaviors and disturbances in adolescence are being increasingly investigated. The aim of the present study was to investigate the sleep habits of adolescents living in provincial Greece. Methods: Responses to pre‐constructed questionnaires on sleep habits and disturbances from 471 high‐school students (259 boys; 212 girls), aged 14–18 years, attending four high schools of rural and semi‐urban areas in north‐western Greece, were analyzed. Results: The median nocturnal and total sleep duration was 7.5 h (range, 2.5–11 h) and 8.5 h (range, 2.5–14 h), respectively, and the average bedtime was 23.55 hours. Male students, older adolescents and residents of towns went to bed later than female students, younger adolescents and residents of villages (P = 0.039, P = 0.0003 and P = 0.056, respectively). Siesta on a regular basis was reported by 43% and on an occasional basis by 46% of the students. Siesta median duration was 1.5 h (range 0.5–4.5 h). Daytime sleepiness, difficulties in morning awakening and in falling asleep, and night awakenings were reported by 26.3%, 17.4%, 17.2% and 11.2%, respectively. Students who had siestas reported less daytime sleepiness (P < 0.0001). Significant differences were observed between boys and girls regarding sleep disturbances. Conclusion: Adolescents in provincial Greece present with a different sleep pattern as compared to their northern European peers, characterized by late bedtime and midday siesta. Similarly to their peers in other countries, considerable rates of sleep disturbances were reported.     

Understanding sleep habits and associated factors can help to improve sleep in high school adolescents

We aimed to describe the sleep profiles and associated factors of poor sleep in adolescents. We gave a sleep questionnaire and Strengths and Difficulties Questionnaire to 3,441 high school adolescents (15-18 years) in Gaziantep, Turkey. Adolescents reported a requirement of 10.4 hours of sleep on average to feel their best during the day. However, total night sleep time (TNST) was 7.42 +/- 1.48 hours on school nights and 9.40 +/- 1.37 on non-school nights. TNST of > or =9 hours on both school nights and non-school nights was detected in 8.2%. Average bedtime and wake-up time were 23:16 and 06:41 on school nights. Bedtime was approximately 30 minutes later on non-school nights. The shift in wake-up time was nearly 2.5 hours. Statistical analysis by logistic regression model showed that TNST was most significantly correlated with school start time (morning versus afternoon) irrespective of school or non-school nights. TNST on school nights was negatively correlated with age, passive smoking at home, drinking tea/coffee, and conduct problem, whereas TNST on non-school nights was negatively correlated with the mother's education, male gender, body mass index, number of household members, and having a television in the bedroom. Daytime napping (21.3%) was associated with morning start time, age, female gender, and mother's education. Sleep-onset insomnia with sleep latency >30 minutes (21%) was not related to age or gender; however, it was associated with abnormal breathing during sleep. The findings revealed that inadequate sleep is quite prevalent among high school adolescents. Given the fact that most of the associated factors are modifiable, inadequate sleep is not inevitable for adolescents.     

Prevention and treatment of sleep deprivation among emergency physicians

Emergency physicians commonly experience sleep deprivation because of the need to work shifts during evening and late night hours. The negative effects of this problem are compounded by job stress and traditional methods of scheduling work shifts. Sleep deprivation may be reduced by schedules designed to lessen interference with normal sleep patterns and circadian rhythms. Pharmacological treatments for sleep deprivation exist in the form of alertness-enhancing agents, caffeine and modafinil. Sleep-promoting agents may also help treat the problem by helping physicians to sleep during daytime hours. Minimizing sleep deprivation may help prevent job burnout and prolong the length of an emergency physician's career.     

Sleep problems in young infants and maternal mental and physical health

AIM: Sleep problems in the second 6 months of life are common and associated with maternal depression. This paper extends previous research to (i) establish the prevalence of sleep problems in younger infants from a broader socio-economic spectrum, (ii) examine the relationship between infant sleep problems and maternal physical, as well as mental, health, and (iii) explore mothers' sleep quality as a potential mediator of this relationship. METHODS: Design: Cross-sectional, community survey in Melbourne, Australia. Sample: Mothers of 3- to 6-month-old infants (mean 4.6 months) recruited from well-child clinics in six sociodemographically diverse metropolitan local government areas. Outcome measures: Maternal mental and physical health; standardised questionnaire on infant sleep patterns; maternal report of an infant sleep problem (yes/no). RESULTS: The survey was completed by 692 mothers; 237 (34%) reported an infant sleep problem, of whom 73 (31%) rated the problem as severe. Sleep patterns characterising a problem included the infant waking seven nights per week, nursing the infant to sleep at the beginning of the night, the infant sleeping in the parent's room, and parental disagreement regarding managing infant sleep. There was no relationship between sleep problems and socio-economic levels. Mothers reporting infant sleep problems had poorer mental and physical health compared with those not reporting sleep problems. CONCLUSION: Sleep problems are common in early infancy across metropolitan socio-economic levels and are associated with poorer maternal health and well-being. Preventive strategies for infant sleep problems need to begin early in primary care to improve mothers' health.     

Effect of current breastfeeding on sleep patterns in infants from Asia-Pacific region

Aim: The aim of this study was to assess the relationship between breastfeeding and sleep patterns in infants from Asia‐Pacific region. Methods: Parents of 10 321 infants (0–11 months) from Australia, China, Hong Kong, India, Indonesia, Korea, Japan, Malaysia, New Zealand, the Philippines, Singapore, Taiwan, Thailand and Vietnam completed an expanded version of the Brief Infant Sleep Questionnaire. Results: Overall, 4714 (45.72%) were currently being breastfed; 61.3% of those between 0 and 5 months and 36.6% of those between 6 and 11 months. Currently breastfed infants, when compared with not currently breastfed infants, had a significant increase in the number and duration of night‐time wakings and less consolidated sleep. Interestingly, currently breastfed infants less than 6 months also showed longer duration of daytime sleep and obtained more sleep overall. Of note, of those who were currently breastfed, those infants who were nursed back to sleep during night, woke up more often at night (2.41 vs. 1.67 times) and had shorter continuous night‐time sleep period (5.58 vs. 6.88 h; P < 0.001). There was no significant difference between breastfeeding and non‐breastfeeding infants in the number of night wakings, when the nursing to sleep variable was controlled for in the analysis of variance. Conclusion: Breastfeeding is associated with reduced sleep consolidation in infants. This relationship, however, may be moderated by parenting practices of nursing to sleep and back to sleep during the night. Thus, parents of infants with night waking problems should be encouraged to limit the association between nursing and falling to sleep, to improve sleep while maintaining breastfeeding.     

Effects of nasal continuous positive airway pressure on apnoea index and sleep in infants

Objectives: We examined the effectiveness of nasal continuous positive airway pressure (CPAP) for treatment of sleep apnoea in infants.
Methodology: We studied five infants who all had significant central and mixed apnoea and severe sleep fragmentation. Polysomnographic recordings were performed on 2 consecutive nights in these infants. One night was used as a control study and during the second night nasal CPAP was applied throughout the night
Results: Nasal CPAP significantly reduced apnoea in each infant, with the apnoea index (apnoeas/h) decreasing from 65.6± 14.6 during the control study to 10.5± 14.6 during CPAP in non-rapid eye movement (non-REM) sleep, and from 106± 13.9 during the control study to 26.6± 13.9 during CPAP in REM sleep. Nasal CPAP also improved the sleep fragmentation markedly; REM sleep increased from 14.2± 1.2% of sleep during the control study to 27.1 ± 1.2% of sleep during CPAP.
Conclusions: We conclude that nasal CPAP is an effective treatment for infantile apnoea. Sleep apnoea in these infants is associated with profound sleep fragmentation, which is reversed by nasal CPAP.     

长沙市学龄儿童睡眠不足对智力结构的影响

目的：探讨小学生睡眠不足对智力发育的影响,为有效干预提供科学理论依据。方法：2009 年 6 月至 2010 年 4 月,在长沙市4 个行政区分层随机抽取4所小学10~11岁5年级小学生316名进行调研,了解其不同程度的睡眠不足在中国韦氏儿童智力量表测验上反映的智力结构特点。结果：收回有效问卷286份,应答率90.5%,其中睡眠时间正常（夜间睡眠时间≥8 h,对照组）106人,睡眠不足180人（夜间睡眠时间<8 h,睡眠不足组）。睡眠不足组各项分测验、言语智商、操作智商和总智商得分均显著低于对照组（P<0.05）,语言理解因子和记忆/注意因子得分亦显著低于对照组（P<0.05）。与对照组比较,中度睡眠不足亚组语言智商、总智商及语言理解因子、记忆/注意因子得分降低（P<0.05）;重度睡眠不足亚组各项得分均降低（P<0.05）。睡眠不足组及中度和重度睡眠不足亚组儿童中智力不平衡者的比例显著高于对照组（P<0.05）。结论：睡眠不足对小学生智力发育有不良影响,尤其是对言语智商发育的影响较大,主要发生于中、重度睡眠不足的小学生。     

The characteristics of sleep-wake rhythm in adolescents aged 15-20 years. A survey made at school during ten consecutive days]

Adolescents' fatigue is a worrying subject. PATIENTS AND METHOD: A survey was carried out over a period of ten days (a school week between two weekends). Through a daily questionnaire, 386 adolescents aged 15-20 years were asked about sleep onset and offset, time delay of sleep onset, quality of sleep, daytime sleepiness and naps. RESULTS: The results confirmed that the length of sleep was lessened during weekdays. This duration was one hour shorter than on Saturday nights or during holidays. However, a significant delay occurs in sleep onset on Saturday nights and sleep offset on Sunday mornings, which represents the main irregularity in the sleep schedule. Poor quality of sleep is due to difficulties in sleep onset (16%) and night awakenings (39%). Daytime sleepiness is reported by 38% of the adolescents, and many of them have a nap on Sundays, or other days of the week. Daytime activities (out-of-school sports, particularly) and evening activities were studied as well as the use of hypnotics and stimulants. CONCLUSION: This work stresses sleep insufficiency during the week at school, changes in sleeping patterns during weekends, and sometimes poor quality of sleep. Similar facts have already been found in children, and this may explain the consequences on the life and behaviour of adolescents. The population has to be informed about the effects of sleep on health.     

Sleep problems of school-aged children: a complementary view

The aim of this population-based multicentre study was to evaluate the prevalence rates of sleep problems among 8-9-y-old children. The sample consisted of 5813 Finnish children, making up 10% of the age cohort. Both parents and children provided information. Disturbed sleep was reported by 21.7% of parents. Most of the problems were mild; only 0.3% were serious. Dyssomnias were frequent: 11.1% had difficulties with sleep onset, 7.1% with night waking and 2.3% with waking too early. Multiple sleep problems were present in 9.1% of the children. 17.8% of children reported disturbed sleep, 12.7% had problems many nights and 5.1% every night. In 32.0% of cases, either the parent or the child reported disturbed sleep; 7.4% of these reports came from both the parent and the child, 14.1% from the parent only and 10.3% from the child only. The correspondence between informants was poor (kappa = 0.224). Sleeping problems were associated with somatic and psychiatric problems. It is concluded that by restricting questioning to parents only, one-third of all potential cases of sleep problems may go unnoticed. In order to increase the sensitivity of screening children's sleep problems, both parents and children should provide information in epidemiological settings as well as in clinical work.     

Sleep problems in healthy preadolescents

Few data currently exist concerning the sleep problems of preadolescents. A parent report questionnaire concerning sleep habits and problems was developed. The questionnaires were completed by the parents of 1000 unscreened elementary school children attending the third, fourth, and fifth grades. The schools were randomly selected from an urban area. Of the 1000 questionnaires, 972 were completed and could be used for statistical analysis. Among the parents, 24% reported sleeping poorly and 12% regularly relied on sedatives to induce sleep. Sleep difficulties lasting more than 6 months were present in 43% of the children. In 14% (132 of 972), sleep latency was longer than 30 minutes, and more than one complete arousal occurred during the night at least two nights per week. The following variables were seen among the poor sleepers: lower parental educational and professional status, parents who were more likely to be divorced or separated, and more noise or light in the rooms were they slept. They also presented a higher incidence of somnambulism, somniloquia, and night fears (nightmares and night terrors) than the children who slept well. Boys who slept poorly were significantly more likely to have insomniac fathers (P less than .010). Regular use of sedatives was described in 4% (5 of 132) of the children who slept poorly. Among the "poor sleepers," 21% (33 of 132) had failed 1 or more years at school. School achievement difficulties were encountered significantly more often among the poor sleepers than among the children without sleep problems (P = .001). Of the families with children suffering from sleep problems, 28% expressed a desire for counseling.(ABSTRACT TRUNCATED AT 250 WORDS)     

Nodding off or switching off? The use of popular media as a sleep aid in secondary-school children

AIM: To describe the use of media as a sleep aid in adolescents and relate this to their sleep routines and feelings of tiredness. METHODS: A questionnaire about using media as a sleep aid, media presence in bedrooms, time to bed and time out of bed on average weekdays and average weekend days, and questions regarding level of tiredness in the morning, at school, after a day at school and after the weekend was completed by 2546 seventh and 10th grade children in a random sample of 15 schools. RESULTS: Of the adolescents, 36.7% reported watching television to help them fall asleep. In total, 28.2% of the boys and 14.7% of the girls used computer games as a sleep aid. Music was used to fall asleep by 60.2% of the adolescents in this sample. About half of the adolescents read books to fall asleep. Except for reading books, using media as a sleep aid is negatively related to respondents' time to bed on weekdays, their number of hours of sleep per week and their self-reported level of tiredness. CONCLUSION: Using media as a sleep aid appears to be common practice among adolescents. Those who reported using music, television, and computer games more often as a sleeping aid slept fewer hours and were significantly more tired.     

Sleep quality among parents and their children during COVID-19 pandemic

ObjectiveTo evaluate sleep characteristics of parents and their children during the COVID-19 pandemic and predictors for sleep disturbances.MethodsCross-sectional web-based study using an online survey made available for dyads of parents and their children during the 7^th week of quarantine in southern Brazil. Parents' and adolescents’ sleep were characterized using the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale. For children aged 0-3 years parents completed the Brief Infant Sleep Questionnaire, for those aged 4-12 years the Sleep Disturbance Scale for Children. Parents also informed, subjectively, their perception about sleep habits during social distancing. Multiple regression was run to predict sleep disturbances in adults using independent variables: sex, income, education, children age, and children with sleep disturbances.ResultsData from 577 dyads showed sleep alterations in 69,8% of adults, in 58,6% of children aged 0-3 years, 33,9% in the 4-12 years range (with a predominance of disorders of initiating or maintaining sleep), and 56,6% in adolescents. Sex (female) and children with sleep disturbances were significant predictors of a sleep problem in parents (p < 0.005). Subjective perception revealed complaints related to emotional concerns such as anxiety and fear in adults and due to alterations in routine in children and adolescents.ConclusionThe present study's data showed an increased rate of sleep problems among families during quarantine both measured by validated instruments and also based on personal perception.     

Sleep deprivation, disorganization and fragmentation during opiate withdrawal in newborns

OBJECTIVE: To determine specific sleep characteristics in neonatal opiate withdrawal, referred to as the Neonatal Abstinence Syndrome (NAS), by measuring sleep efficiency, deprivation, disorganization and fragmentation in three groups: (i) healthy term neonates; (ii) opiate-exposed neonates who were treated for opiate withdrawal; and (iii) a group of opiate-exposed neonates who did not require treatment. METHODS: A cohort study recording sleep patterns of neonates at 2-10 days of age (after 36 or more weeks of gestation) was carried out. Twenty-one neonates were exposed to opiates during pregnancy and 15 neonates were healthy controls. Sleep characteristics were predefined, and treated newborns were divided into early and stabilized treatment groups. Polygraphic recordings of sleep, movement and breathing were made continuously after a daytime feed. RESULTS: Sleep deprivation, disorganization and fragmentation were found in newborns with NAS and were associated with the severity of the withdrawal. Neonates treated for NAS displayed increased wakefulness during early treatment (deprivation), but were similar to controls once stabilized. Both treated and non-treated groups had reduced amounts of quiet sleep (deprivation). Treated newborns showed an increase in indeterminate sleep (disorganization) and arousals-to-wakefulness (fragmentation). CONCLUSION: This study determined the exact nature and degree of sleep disturbances in newborns during acute opiate withdrawal. The findings contribute to a further understanding of the physiology underlying neonatal opiate withdrawal and suggest that some changes in sleep are due to opiate withdrawal but others may reflect opiate dependency in utero.     

Sleep habits and disturbances in Malaysian children with epilepsy

Aims: To compare sleep habits and disturbances between Malaysian children with epilepsy and their siblings (age range 4–18 years) and to determine the factors associated with greater sleep disturbance. Methods: The Sleep Disturbance Scale for Children (SDSC) questionnaire was completed by the primary caregiver for 92 epileptic children (mean age 11.1 years, 50 male, 42 females) and their healthy siblings (mean age 11.1 years, 47 males, 45 females). Details of sleep arrangements and illness severity were obtained. Multiple regression analysis was used to determine factors associated with high Total SDSC scores in epileptic patients. Results: Compared with their siblings, epileptic children had significantly higher total SDSC score (difference between means 8.7, 95% confidence interval (CI) 6.4–11.1) and subscale scores in disorders of initiating and maintaining sleep (3.9, 95% CI 2.8–5.2), sleep–wake transition disorders (2.1, 95% CI 1.3–2.9), sleep‐disordered breathing (0.7, 95% CI 0.3–1.1) and disorders of excessive sleepiness (1.5, 95% CI 0.6–2.4). Epileptic children had a higher prevalence of co‐sleeping (73.7% vs 31.5%) and on more nights per week (difference between means 3, 95% CI 2.0–3.9) than their siblings. Higher Epilepsy Illness Severity scores were associated with higher total SDSC scores (P= 0.02). Conclusion: Co‐sleeping was highly prevalent in children with epilepsy, who also had more sleep disturbances (especially problems with initiating and maintaining sleep and sleep–wake transition disorders) than their siblings. Epilepsy severity contributed to the sleep disturbances. Evaluation of sleep problems should form part of the comprehensive care of children with severe epilepsy.     

Severe sleep problems among infants in a normal population in Sweden: prevalence, severity and correlates

The aim of this study was to explore the prevalence of parentally experienced infant sleep problems, with special interest in severe problems, in a total community sample of 2518 infants aged 6-18 mo. Correlates to severe sleep problems were sought. The families were approached using a questionnaire and 83% responded. Data from the collection procedure point to a non-selective dropout. Sixteen percent of the parents reported their children as having moderate or severe difficulties in falling asleep at night (sleep refusal, bedtime struggles) and 30% reported frequent night waking. Almost all (93%) of the parents had sought help at the Child Health Centre (CHC), but only 48% were satisfied with the support and advice they got. Severe sleep problems as defined by the ICSD (International Classification of Sleep Disorders, 1990) were found in 129 of the children (6.2%), who were studied in detail, with the rest of the population as controls. Severe sleep problems were found to be correlated with parental worries and anxiety concerning infant health (although the children were reported as being as healthy as the controls), infant feeding problems and intensive parental interventional behaviour (especially feeding) during the evening and night. A common factor of insecurity in the parental role is suggested.