The effectiveness of the varicella vaccine in clinical practice.

BACKGROUND: A live attenuated varicella vaccine was approved for use in the United States in March 1995 and is recommended for all susceptible persons 12 months of age or older. METHODS: To assess the effectiveness of the varicella vaccine, we conducted a case-control study with two controls per child with chickenpox, matched according to both age and pediatric practice. Children with potential cases of chickenpox were identified by active surveillance of pediatric practices in the New Haven, Connecticut, area. Research assistants visited the children on day 3, 4, or 5 of the illness, assessed the severity of the illness, and collected samples from lesions to test for varicella-zoster virus by polymerase chain reaction (PCR). RESULTS: From March 1997 through November 2000, data collection was completed for 330 potential cases, of which 243 (74 percent) were in children who had positive PCR tests for varicella-zoster virus. Of the 56 vaccinated children with chickenpox, 86 percent had mild disease, whereas only 48 percent of the 187 unvaccinated children with chickenpox had mild disease (P<0.001). Among the 202 children with PCR-confirmed varicella-zoster virus and their 389 matched controls, 23 percent of the children with chickenpox and 61 percent of the matched controls had received the vaccine (vaccine effectiveness, 85 percent; 95 percent confidence interval, 78 to 90 percent; P<0.001). Against moderately severe and severe disease the vaccine was 97 percent effective (95 percent confidence interval, 93 to 99 percent). The effectiveness of the vaccine was virtually unchanged (87 percent) after adjustment for potential confounders by means of conditional logistic regression. CONCLUSIONS: Varicella vaccine is highly effective as used in clinical practice.

Willingness of directors of child care centers to care for children with chronic infections.

Directors of 150 child care centers were surveyed about their willingness to accept children with HIV or hepatitis B infection. Among 100 respondents 58% agreed to accept HIV-positive children and 23% would accept hepatitis B-positive children.

Care to underserved children: Residents' attitudes and experiences.

OBJECTIVES: To examine: 1) the relationship between residents' responses toward caring for underserved children and families during residency and their perceptions of their continuity clinic experience; and 2) which characteristics are related to continuing to care for the underserved after completion of training. DESIGN: Cross-sectional descriptive study. METHODS: A 49-item questionnaire was mailed to 210 third-year pediatric residents at 12 urban training programs in the Northeast in May 1995. Information was collected about residents' emotional responses toward caring for underserved families, their assessments of clinic operations, their sense of effectiveness in caring for underserved patients in continuity clinic, preresidency experiences with the underserved, and their intent to care for the underserved after training. RESULTS: Of 210 surveys mailed, 71% were returned. Thirty-six percent of residents planned to pursue a career in primary care, 53% did not, and 11% did not answer or were planning a year as chief resident. Fifty-seven percent of all residents planned to devote a portion of their practice toward caring for the underserved after training. Residents whose emotional responses toward caring for the underserved included: 1) not worrying that they had become numb to children's psychosocial difficulties, 2) not feeling angry with how families cared for their children, and 3) feeling more empathy with the underserved had significantly higher mean scores on both their assessment of clinic operations and their sense of effectiveness. The only demographic characteristic associated with a greater sense of effectiveness was being black. To better characterize which residents planned to care for the underserved after training, we examined a subsample of 46 residents who recalled an interest in caring for the underserved during residency training and who were pursuing a career in primary care. Residents that did not recall an interest in caring for the underserved at the onset of residency training were unlikely to have plans to care for the underserved after the completion of training. Within this group residents who planned to care for the underserved after training differed significantly from residents who did not plan to continue this work by feeling a greater sense of effectiveness in clinic, feeling less worried about becoming numb, and having greater empathy for underserved families. CONCLUSIONS: There are a number of identifiable emotional responses residents develop toward caring for the underserved that relate to their perceptions of continuity clinic and whether a resident chooses to continue to care for the underserved after training.

The mother-child interaction and clinical judgment during acute pediatric illnesses.

OBJECTIVES: For acutely ill children living in less than optimal environments, mothers and pediatricians may have a heightened perception of illness severity, a lower specificity of clinical judgments, and a tendency to over-utilize resources. We examined the mother-child interaction in order to understand the relation of less optimal environments to clinical judgment and resource use. STUDY DESIGN: At the 2-week and 6-, 15-, and 24-month well child visits of 316 children, the mother-well child interaction was assessed by using the Biringen's Emotional Availability Scales (EAS). Data were gathered regarding maternal depression and sense of competence, infant temperament, maternal social support, life events, the home environment, and demographics. At ill visits, the mother-ill child interaction was assessed by using the EAS, and mothers and pediatricians independently assessed illness severity using the Acute Illness Observation Scales. Resource use during the illness was evaluated. RESULTS: One thousand nine hundred eight-three acute illnesses were assessed. A less optimal mother-child interaction was significantly (P <.05 for all comparisons) associated with poorer reliability of mothers' judgments, lower specificity of mothers' judgments (71% vs 85%) and pediatricians' judgments (92% vs 97%), and greater use of resources (eg, for hospitalizations, 2.6% of visits vs 0.7%). Adverse maternal, infant, and demographic characteristics were associated with a less optimal mother-well child (r = 0.68) and mother-ill child (r = 0.80) interaction, a heightened perception of illness severity, and greater resource use. CONCLUSION: Less optimal environments adversely affect the mother-child interaction; a poor mother-child interaction is correlated with low specificity of clinical judgment and over-utilization of resources.

Long-term outcomes of persons with Lyme disease.

CONTEXT: Few data exist about the long-term outcomes of patients with Lyme disease. OBJECTIVE: To assess the long-term outcomes of patients with Lyme disease. DESIGN: Two-part project including a community-based longitudinal cohort study and a matched cohort study. SETTING AND PARTICIPANTS: Six hundred seventy-eight patients identified from a random sample of all reports of Connecticut residents with suspected Lyme disease submitted to the Connecticut Department of Public Health from 1984-1991 were evaluated in the longitudinal study; for a random subsample of 212 patients from the larger study, 212 age-matched controls without Lyme disease also were enrolled. MAIN OUTCOME MEASURES: Self-reports or parents' reports of symptoms and ability to perform certain daily activities since diagnosis of Lyme disease; scores on the 36-Item Short-Form Health Survey and the Center for Epidemiologic Studies-Depression scale, for adults, by case-definition status and between patients and controls. RESULTS: Of the 678 patients, 51.6% were female, 34.4% were children, and 64.3% met the national surveillance case definition for Lyme disease. Most patients (85.6%) were treated with antimicrobial agents. Interviews were conducted a median of 51 months after diagnosis (range, 15-135 months). An increased frequency of symptoms (eg, pain, fatigue) or of difficulty with daily activities (eg, performing housework, exercising) was reported by 69% of the patients, although few (19%) of these problems were attributed to Lyme disease. Whenever there was a statistically significant difference in the frequencies of either increased symptoms or increased difficulties with typical activities between those who did or did not meet the surveillance case definition, in all instances the greater frequency of problems was in the group that did not meet the case definition. The frequencies of reports of both increased symptoms and increased difficulties with typical activities among patients who had been diagnosed as having Lyme disease were similar to those among age-matched controls without Lyme disease. CONCLUSIONS: In this cohort, although many patients reported increases in symptoms and/or increased difficulties with typical daily activities between 1 and 11 years after diagnosis of Lyme disease, the frequencies of these reports were similar to the frequencies of such reports among age-matched controls without Lyme disease.

User satisfaction and frustration with a handheld, pen-based guideline implementation system for asthma.

OBJECTIVE: To evaluate clinicians' satisfaction and frustrations with the use of a handheld computer system that implements a guideline for management of childhood asthma exacerbations. SETTING: Nine primary-care pediatric practices. DESIGN: Survey component of a randomized, prospective before-after trial. INTERVENTION: Newton MessagePad outfitted with custom software (called "AsthMonitor") that assists in documentation of clinical findings and provides guideline-based recommendations. RESULTS: Overall, 3 users gave strongly positive global ratings while 6 users were neutral. The majority used the documentation functions concurrently with care. Except for recommendations to administer oxygen (which were unsupported by evidence), users found the recommendations appropriate and appreciated the reminders. Seven of 9 participants believed it took more time to document with AsthMonitor. CONCLUSIONS: Handheld computers are acceptable to some office-based practitioners to provide guideline-based advice within the context of the clinical encounter.

Sleep patterns in newborns and temperament at eight months: a preliminary study.

The sleep patterns of 41 full-term newborn infants were recorded continuously during the first 2 postnatal days. The recordings were made nonintrusively using the Motility Monitoring System while the infants were in the hospital. When the subjects were 8 months old, their mothers filled out the Infant Temperament Questionnaire, which yields scores on nine dimensions of temperament. There were four significant correlations between Day 1 sleep measures and later temperament dimensions; there were eight correlations on Day 2, hardly more than a chance number. The temperament scores were used to classify infants as having Easy, Intermediate, Difficult, or Most Difficult temperament. Profiles of sleep measures for the infants in the four groups differed significantly on Day 1, and the Most Difficult infants showed the most extreme values on all measures. Differences in the predictive findings from Day 1 and Day 2 were attributed to the greater influence of the stress of labor and delivery on the first postnatal day.

Sleep rhythmicity in infants: index of stress or maturation.

The rhythmicity of bouts of quiet sleep (QS) was assessed, starting immediately after the baby's birth. The subjects were 58 healthy fullterm, single-birth, newborn infants, 26 females and 32 males. Using a non-intrusive recording procedure, their sleep was monitored for 24-h periods on the 1st and 2nd postnatal days in the hospital, then for 2 days in the home at 6 months. The cyclicity index permitted determination of the degree of periodicity as well as whether the recurrence of QS bouts showed significant periodicity. The number of subjects with significant cyclicity increased from 34% of the group on postnatal day 1 to 73% at 6 months; cyclicity scores (CS) increased from 0.71 to 0.86; and mean cycle length increased from 51 to 57 min. Infants with significant cyclicity on day 1 had lower mental scores at 6 months; but infants with significant cyclicity at 6 months had higher mental scores at 1 year. In addition, the infants with significant cyclicity on day 1 had lower birth weights and were born to younger mothers; but these relationships were also reversed at 6 months. Finally, cyclicity scores at 6 months were significantly correlated with 1-year mental scores, but the function of this relationship was quadratic. Thus, while significant cyclicity was found from the first postnatal day, the results suggest that regularity in QS cycles in the newborn period has negative implications for development, while such regularity at 6 months has positive implications-although excessive rigidity in rhythms at the later age, in terms of extremely high cyclicity scores, was also an indicator of developmental compromise.

Infants' earliest sleep/wake organization differs as a function of delivery mode.

The sleep/wake states of newborn infants were investigated as as a function of vaginal and C-section delivery. The subjects were 51 normal full-term infants: 26 vaginally delivered, 12 delivered by emergency C-section, and 13 delivered by elective C-section. Their sleep states and wakefulness were continuously recorded from the time of birth throughout their stay in the hospital, that is, the first 2 postnatal days for the vaginally delivered infants and 5 days for the C-section infants. Sleep was recorded using the automated Motility Monitoring System, which permits 24-hr recordings without instrumentation of the subject. During the 1st postnatal day, both C-section groups showed state patterns that differed significantly from those of the vaginally delivered infants. Analyses for single states indicated that both C-section groups had significantly less active sleep, and the elective group had more wake and more sleep--wake transition than the vaginal group. The two C-section groups did not differ significantly on any measure. Only the vaginally delivered infants showed significant day/night differences during the first 2 days, with more wakefulness, shorter mean sleep periods and shorter longest-sleep periods during the daytime on both days. The results of this study indicate that the earliest postnatal sleep patterns differ and the diurnal sleep rhythm is disrupted as a result of surgical delivery.

Ultradian and diurnal cyclicity in the sleep states of newborn infants during the first two postnatal days.

OBJECTIVE: The purpose of this study was to investigate both ultradian and diurnal cyclicity in the sleep states of newborn fullterm infants during the first 2 postnatal days. METHODS: The sleep of 31 healthy newborn infants was recorded continuously throughout the first 2 postnatal days, starting immediately after birth, using an automated Motility Monitoring System (MMS). The MMS consists of a pressure sensitive mattress pad connected to an amplifier and a small 24-h analog recorder. A single channel of analog signals produced by the infant's respiration and body movements was recorded and then scored in 30-s epochs for Active Sleep. Quiet Sleep, Active-Quiet Transition, Sleep-Wake Transition, and Wake. DATA ANALYSES: The 48 h of recording were divided into successive 12-h periods from 07:00 h to 19:00 h (day) and 19:00 h to 07:00 h (night), and all measures were derived for each day and night period. Both cross-sectional and repeated measures analyses were used because all babies were not represented in all day/night periods. RESULTS: Day/night differences in state variables: On both days, there was greater Wakefulness, shorter Quiet Sleep Bout Lengths, shorter Mean Sleep Periods and shorter Longest Sleep Periods during the daytime. On day 1 only, there was less Quiet Sleep, shorter Quiet Sleep Bout Lengths and more Sleep-Wake Transition during the daytime. On day 2, repeated measures analyses revealed two additional day/night differences: less Quiet Sleep and more Sleep-Wake Transition during the daytime. Day/night differences in Quiet Sleep cyclicity: 28 sleep periods met the criteria for analysis of Quiet Sleep cyclicity, and only six of these occurred during the daytime. Seventeen of 28 analyzable sleep periods showed significant Quiet Sleep cyclicity. Only two of these occurred during the daytime. CONCLUSIONS: Contrary to the prevailing view of developing sleep rhythms, the results of this study suggest that newborn infants exhibit both ultradian ad diurnal cyclicity in their sleep patterns from the earliest postnatal period.

Infant sleep during the first postnatal day: an opportunity for assessment of vulnerability.

OBJECTIVE: The purpose of this study was to describe the sleep of newborns throughout the first 48 postnatal hours and to relate their earliest sleep characteristics to developmental status at 6 months. METHODS: The sleep of 36 healthy newborns was recorded continuously throughout the first two postnatal days, starting immediately after birth, using an automated Motility Monitoring System. The Motility Monitoring System consists of a pressure-sensitive mattress pad connected to an amplifier and a small 24-hour analog recorder. A single channel of analog signals produced by the newborn's respiration and motility is continuously recorded onto a 60-minute cassette tape. The signals are digitized and scored, in 30-second epochs, for Active Sleep, Quiet Sleep, Active-Quiet Transition, Sleep-Wake Transition, and Wake. In addition to the percent of time spent in each state, the Mean Bout Length of Active Sleep, Mean Bout Length of Quiet Sleep, Mean Sleep Period, Longest Sleep Period, and Arousals in Quiet Sleep were also measured. RESULTS: On postnatal day 1, four measures were significantly related to 6-month Bayley mental scores: Mean Sleep Period, Longest Sleep Period, Sleep-Wake Transition, and Arousals in Quiet Sleep; and two measures were significantly related to Bayley motor scores: Mean Sleep Period and Sleep-Wake Transition. On postnatal day 2, none of the measures were related to mental scores, while two measures were related to the motor scores: Quiet Sleep and Mean Bout Length of Quiet Sleep. CONCLUSIONS: The results suggest that the newborn's sleep characteristics during the first postnatal day provide uniquely sensitive indices of later neurobehavioral function.