Biomedical subjects

Judy A Bean

Publications and source records attributed to Judy A Bean.

At least 19 recordsLinked to original sources

PubMed2007

Aerosolized red-tide toxins (brevetoxins) and asthma.

BACKGROUND: With the increasing incidence of asthma, there is increasing concern over environmental exposures that may trigger asthma exacerbations. Blooms of the marine microalgae, Karenia brevis, cause red tides (or harmful algal blooms) annually throughout the Gulf of Mexico. K brevis produces highly potent natural polyether toxins, called brevetoxins, which are sodium channel blockers, and possibly histamine activators. In experimental animals, brevetoxins cause significant bronchoconstriction. In humans, a significant increase in self-reported respiratory symptoms has been described after recreational and occupational exposures to Florida red-tide aerosols, particularly among individuals with asthma. METHODS: Before and after 1 h spent on beaches with and without an active K brevis red-tide exposure, 97 persons >or= 12 years of age with physician-diagnosed asthma were evaluated by questionnaire and spirometry. Concomitant environmental monitoring, water and air sampling, and personal monitoring for brevetoxins were performed. RESULTS: Participants were significantly more likely to report respiratory symptoms after K brevis red-tide aerosol exposure than before exposure. Participants demonstrated small, but statistically significant, decreases in FEV(1), midexpiratory phase of forced expiratory flow, and peak expiratory flow after exposure, particularly among those participants regularly using asthma medications. No significant differences were detected when there was no Florida red tide (ie, during nonexposure periods). CONCLUSIONS: This study demonstrated objectively measurable adverse changes in lung function from exposure to aerosolized Florida red-tide toxins in asthmatic subjects, particularly among those requiring regular therapy with asthma medications. Future studies will assess these susceptible subpopulations in more depth, as well as the possible long-term effects of these toxins.

Adolescent↗

PubMed2006

Reductions in cross-neutralizing antibody responses in infants after attenuation of the human rotavirus vaccine candidate 89-12.

The G1P1A[8] rotavirus vaccine candidate 89-12, the precursor to Rotarix, stimulated high titers of neutralizing antibodies to non-G1/P1A[8] serotypes of human rotavirus in naturally infected subjects before attenuation by cell-culture passages. These responses were greatly diminished in young infants (median age, 11 weeks) administered the attenuated vaccine. Because of the possibility of improved responses in older infants, the immunogenicity of the 89-12 vaccine candidate was evaluated after administration of 2 doses beginning at either 4 or 6 months of age. As was found in young infants, neutralizing antibody responses to non-G1/P1A[8] rotaviruses were considerably lower than those observed after natural infection. The reasons identified were overall (P<.0001) lower neutralizing antibody responses stimulated by the attenuated 89-12 strain, compared with those stimulated by its virulent precursor, and 5 mutations selected in the gene encoding the immunodominant VP4 (P) neutralization protein. Even so, the Rotarix vaccine developed from attenuated 89-12 was found to elicit excellent protection against non-G1 rotaviruses.

Administration, Oral↗

PubMed2006

Self-esteem in adolescent females.

PURPOSE: Self-esteem is a major "predictor" of satisfaction with life. This longitudinal study examined mean and individual changes in self-esteem, and how self-esteem is affected by race and body mass. METHODS: Girls were recruited at ages 9 and 10 years, and followed to age 22 years. The Harter Self-Perception Profile was administered every other year, analyzing scores from the Global Self-Worth Scale, by age or developmental phase: ages 9-12 (I), 13-16 (II), and 17-22 (III). Regression modeling included main effects and interactions between age/phase, race, and body mass index (BMI). RESULTS: Self-worth was greater in black than white women, and greater with lower BMI in both races. In the model with age ("traditional model") (with race and BMI), significant variables included BMI (inverse relationship) and the interactions between age and race, race and BMI, and the triple interaction between age, race, and BMI. In the model with phase ("transitional model") (with race and BMI), BMI, and the interactions between BMI and race, and race and phase, were significant. For example, self-worth was generally lower in Phase II (middle adolescence) for white women. Self-esteem tracked significantly (correlation 0.22, p < .001). An individual's self-worth during any given phase of adolescence was correlated significantly with the other two phases. CONCLUSIONS: In this longitudinal analysis of self-esteem in adolescent girls, race and BMI are important predictors of self-esteem. Self-esteem is consistent across the phases of adolescence, and comparable with other personality traits. As noted by others, lower levels of self-esteem may increase the vulnerability of adolescents to risky behaviors.

Adolescent↗

PubMed2006

Protection against rotavirus shedding after intranasal immunization of mice with a chimeric VP6 protein does not require intestinal IgA.

Intranasal immunization of mice with chimeric VP6 and the adjuvant LT(R192G) consistently elicits >95% reductions in fecal rotavirus shedding following challenge. To determine the association between mucosal antibody and protection, we immunized BALB/c wt and J chain knockout (Jch-/-) mice with VP6 and either LT(R192G) or cholera toxin (CT). Both strains developed nearly equal levels of serum rotavirus IgG, but Jch-/- mice, which cannot transport dimeric IgA across epithelial cell surfaces, developed >4-fold higher levels of serum rotavirus IgA. Stool rotavirus IgA was present in wt but undetectable in Jch-/- mice. When challenged with rotavirus strain EDIM, reductions in rotavirus shedding were nearly identical in VP6-immunized wt and Jch-/- mice (i.e., 97% and 92%, respectively; P > 0.01). Th1 CD4 T cell responses were also detected in VP6-immunized animals based on high levels of IFN-gamma and IL-2 found after in vitro VP6 stimulation of spleen cells. Therefore, protection induced by intranasal immunization of mice with VP6 and adjuvant does not depend on intestinal rotavirus IgA antibody but appears to be associated with CD4 T cells.

Adjuvants, Immunologic↗

PubMed2006

A randomized clinical trial of dietary calcium to improve bone accretion in children with juvenile rheumatoid arthritis.

OBJECTIVE: To examine a behavioral intervention (BI) to increase calcium intake in children with juvenile rheumatoid arthritis (JRA) on calcium intake and bone mass 6 and 12 months after treatment. STUDY DESIGN: A randomized trial compared a 6-session BI to a 3-session enhanced standard of care (ESC) with 49 children ages 4 to 10 years with JRA. Calcium intake was assessed via 3-day diet diaries. Total body bone mineral content (BMC), arms and legs BMC, and lumbar spine bone mineral density were assessed by dual energy x-ray absorptiometry. RESULTS: BI maintained an average calcium intake of 1500 mg/d at 6- and 12-month follow-up. This was greater than their baseline level of 972 mg/d, but not greater than the intake of 1300 mg/day maintained by ESC (P=.09). The BI had a 4% and 2.9% greater gain in total body bone mineral content than ESC at 6 and 12 months, respectively (P=.005), and a 7.1% and 5.3% greater gain in arms and legs BMC at 6 and 12 months than ESC (P=.0007). CONCLUSIONS: BI is effective in increasing calcium intake and BMC in children with JRA over a 12-month period.

Adult↗

PubMed2006

Mice develop effective but delayed protective immune responses when immunized as neonates either intranasally with nonliving VP6/LT(R192G) or orally with live rhesus rotavirus vaccine candidates.

Rotavirus vaccines are delivered early in life, when the immune system is immature. To determine the effects of immaturity on responses to candidate vaccines, neonatal (7 days old) and adult mice were immunized with single doses of either Escherichia coli-expressed rotavirus VP6 protein and the adjuvant LT(R192G) or live rhesus rotavirus (RRV), and protection against fecal rotavirus shedding following challenge with the murine rotavirus strain EDIM was determined. Neonatal mice immunized intranasally with VP6/LT(R192G) were unprotected at 10 days postimmunization (dpi) and had no detectable rotavirus B-cell (antibody) or CD4(+) CD8(+) T-cell (rotavirus-inducible, Th1 [gamma interferon and interleukin-2 {IL-2}]-, Th2 [IL-5 and IL-4]-, or ThIL-17 [IL-17]-producing spleen cells) responses. However, by 28 and 42 dpi, these mice were significantly (P >or= 0.003) protected and contained memory rotavirus-specific T cells but produced no rotavirus antibody. In contrast, adult mice were nearly fully protected by 10 dpi and contained both rotavirus immunoglobulin G and memory T cells. Neonates immunized orally with RRV were also less protected (P=0.01) than adult mice by 10 dpi and produced correspondingly less rotavirus antibody. Both groups contained few rotavirus-specific memory T cells. Protection levels by 28 dpi for neonates or adults were equal, as were rotavirus antibody levels. This report introduces a neonatal mouse model for active protection studies with rotavirus vaccines. It indicates that, with time, neonatal mice develop full protection after intranasal immunization with VP6/LT(R192G) or oral immunization with a live heterologous rotavirus and supports reports that protection depends on CD4(+) T cells or antibody, respectively.

Adjuvants, Immunologic↗

PubMed2005

Left ventricular function in children with sleep-disordered breathing.

Severe obstructive sleep apnea in children leads to congestive heart failure. We studied the early changes in left ventricular function across a range of severity of the disorder. A dose-dependent decrease in diastolic function with increased severity of obstructive apnea was demonstrated.

Adolescent↗

PubMed2005

Pediatric cricotracheal resection: surgical outcomes and risk factor analysis.

OBJECTIVE: To identify risk factors for operation-specific outcomes of pediatric cricotracheal resection (CTR). DESIGN: We identified the first 100 consecutive children undergoing CTR at our institution from January 1, 1993, to December 31, 2004. Retrospective review of medical records provided data on demographics, operation dates, decannulation dates, and proposed risk factors, including age, stenosis grade, vocal cord function, Down syndrome, history of distal tracheal surgery, history of open laryngotracheal surgery, presence of tracheotomy at the time of operation, use of suprahyoid release, extended CTR, and use of chin-to-chest sutures. Complete data sets were available for 93 patients. We performed multivariable logistic regression analysis to identify significant independent risk factors. SETTING: A tertiary care children's hospital. PATIENTS: All patients younger than 18 years who underwent CTR at our institution. MAIN OUTCOME MEASURES: Operation-specific and overall decannulation rates. RESULTS: Results of the preoperative evaluation showed grade III or IV stenosis in 89 patients (96%). The overall decannulation rate included 87 patients (94%); the operation-specific decannulation rate, 66 patients (71%). The only significant risk factor for failure to decannulate after 1 operation was the presence of unilateral or bilateral vocal cord paralysis (P = .007). CONCLUSIONS: Cricotraceal resection may be safely performed in patients with multiple airway lesions. Patients with a history of vocal cord paralysis who undergo CTR often require more than 1 open airway procedure for decannulation and should be counseled appropriately. This study represents the largest reported series of pediatric CTR.

Adolescent↗

PubMed2005

Theophylline versus terbutaline in treating critically ill children with status asthmaticus: a prospective, randomized, controlled trial.

OBJECTIVE: To compare the efficacy of theophylline, terbutaline, or theophylline combined with terbutaline treatment in critically ill children with status asthmaticus who are already receiving continuous nebulized albuterol and intravenous corticosteroids. DESIGN: Randomized, prospective, controlled, double-blind trial. SETTING: Pediatric intensive care unit of a tertiary-care children's medical center. PATIENTS: Forty critically ill children between the ages of 3 and 15 yrs with impending respiratory failure secondary to status asthmaticus. INTERVENTIONS: All patients received intravenous methylprednisolone and continuous nebulized albuterol. The three study groups received theophylline plus placebo (group 1), terbutaline plus placebo (group 2), or theophylline and terbutaline together (group 3). MEASUREMENTS AND MAIN RESULTS: Differences in baseline characteristics, change in clinical asthma score over time, length of pediatric intensive care unit stay, and incidence of adverse events were determined. The three study groups were similar in age, gender, race, asthma severity, and treatment. There were no differences in clinical asthma score over time, length of pediatric intensive care unit stay, or incidence of adverse events between the three groups, with the exception of a higher incidence of nausea in children in group 3. The median hospital cost of medication and theophylline blood levels was significantly lower in group 1 compared with groups 2 and 3 (280 US dollars vs. 3,908 US dollars vs. 4,045 US dollars, respectively, p < .0001). CONCLUSIONS: Theophylline, when added to continuous nebulized albuterol therapy and intravenous corticosteroids, is as effective as terbutaline in treating critically ill children with status asthmaticus. The addition of theophylline to baseline therapy is more cost-effective when compared with terbutaline alone or terbutaline and theophylline together. Theophylline should be considered for use early in the management of critically ill asthmatic children.

Adolescent↗

PubMed2005

Initial evaluation of the effects of aerosolized Florida red tide toxins (brevetoxins) in persons with asthma.

Florida red tides annually occur in the Gulf of Mexico, resulting from blooms of the marine dinoflagellate Karenia brevis. K. brevis produces highly potent natural polyether toxins, known as brevetoxins, that activate voltage-sensitive sodium channels. In experimental animals, brevetoxins cause significant bronchoconstriction. A study of persons who visited the beach recreationally found a significant increase in self-reported respiratory symptoms after exposure to aerosolized Florida red tides. Anecdotal reports indicate that persons with underlying respiratory diseases may be particularly susceptible to adverse health effects from these aerosolized toxins. Fifty-nine persons with physician-diagnosed asthma were evaluated for 1 hr before and after going to the beach on days with and without Florida red tide. Study participants were evaluated with a brief symptom questionnaire, nose and throat swabs, and spirometry approved by the National Institute for Occupational Safety and Health. Environmental monitoring, water and air sampling (i.e., K. brevis, brevetoxins, and particulate size distribution), and personal monitoring (for toxins) were performed. Brevetoxin concentrations were measured by liquid chromatography mass spectrometry, high-performance liquid chromatography, and a newly developed brevetoxin enzyme-linked immunosorbent assay. Participants were significantly more likely to report respiratory symptoms after Florida red tide exposure. Participants demonstrated small but statistically significant decreases in forced expiratory volume in 1 sec, forced expiratory flow between 25 and 75%, and peak expiratory flow after exposure, particularly those regularly using asthma medications. Similar evaluation during nonexposure periods did not significantly differ. This is the first study to show objectively measurable adverse health effects from exposure to aerosolized Florida red tide toxins in persons with asthma. Future studies will examine the possible chronic effects of these toxins among persons with asthma and other chronic respiratory impairment.

Adolescent↗

PubMed2005

Occupational exposure to aerosolized brevetoxins during Florida red tide events: effects on a healthy worker population.

Karenia brevis (formerly Gymnodinium breve) is a marine dinoflagellate responsible for red tides that form in the Gulf of Mexico. K. brevis produces brevetoxins, the potent toxins that cause neurotoxic shellfish poisoning. There is also limited information describing human health effects from environmental exposures to brevetoxins. Our objective was to examine the impact of inhaling aerosolized brevetoxins during red tide events on self-reported symptoms and pulmonary function. We recruited a group of 28 healthy lifeguards who are occupationally exposed to red tide toxins during their daily work-related activities. They performed spirometry tests and reported symptoms before and after their 8-hr shifts during a time when there was no red tide (unexposed period) and again when there was a red tide (exposed period). We also examined how mild exercise affected the reported symptoms and spirometry tests during unexposed and exposed periods with a subgroup of the same lifeguards. Environmental sampling (K. brevis cell concentrations in seawater and brevetoxin concentrations in seawater and air) was used to confirm unexposed/exposed status. Compared with unexposed periods, the group of lifeguards reported more upper respiratory symptoms during the exposed periods. We did not observe any impact of exposure to aerosolized brevetoxins, with or without mild exercise, on pulmonary function.

Adolescent↗

PubMed2005

MRI of anterior cruciate ligament injuries and associated findings in the pediatric knee: changes with skeletal maturation.

OBJECTIVE: The objective of our study was to evaluate the MRI characteristics of anterior cruciate ligament (ACL) injuries and associated findings relative to skeletal maturity. We also contrast the frequency of findings in this younger population to adult data. MATERIALS AND METHODS: Eighty-two consecutive knees with an MRI report diagnosis of ACL injury (partial tear, sprain, or complete tear) or tibial spine avulsion fracture imaged over 4 years were retrospectively reviewed. Patients were grouped by degree of skeletal maturity as determined from the MR images. The examinations were reviewed for the type of ACL injury, secondary imaging findings, and associated knee injuries. Findings were correlated to skeletal maturity, and frequencies were compared with adult data. RESULTS: ACL injuries were more common in boys in the skeletally immature group, but more common in girls in the skeletally mature group (p = 0.03). Tibial spine avulsion fractures were most common in skeletally immature patients (p < 0.01), whereas complete tears of the ACL were most common in skeletally mature patients. Associated injuries were less common in the skeletally immature group, but this trend did not reach statistical significance. Most secondary signs of ACL injuries occurred at similar rates in all groups with frequencies similar to those reported in adults. CONCLUSION: ACL injuries in skeletally immature patients are seen more often in boys. Tibial avulsion fractures and partial tears are more common in younger, less rigid skeletons that may absorb the forces of trauma. As children mature, complete ACL tears and associated injuries occur in frequencies approaching those patterns seen in adults. Similarly, skeletally mature girls are affected more often than mature boys.

Adolescent↗

PubMed2004

Diagnostic errors by radiology residents in interpreting pediatric radiographs in an emergency setting.

BACKGROUND: There are few data regarding the frequency and type of diagnostic errors made by radiology residents and fellows ("trainees"). However, increasing interest in reducing medical errors highlights the need to analyze which areas of medical knowledge are most problematic for physicians-in-training, including radiology trainees. Once these areas are identified, they can be emphasized during training. OBJECTIVE: To quantify the diagnostic errors made by radiology trainees interpreting radiographs from a pediatric emergency department. MATERIALS AND METHODS: A total of 23,273 dictations of emergency radiographs performed over a 1-year period at a pediatric hospital were analyzed for corrections after staff interpretation and for type and incidence of missed abnormalities by radiology trainees. Errors were categorized by type of pathology and anatomic region. RESULTS: Of the 80 errors detected, 90% were false negatives and 69% were recurrent. Most errors (69%) involved the diagnosis of fractures and/or dislocations. Sixty-one percent of all recurrent errors involved buckle, Salter II, avulsion, and transverse fractures-yet these cases constituted only 3% of all cases seen during the study period. CONCLUSION: The most common errors made by radiology trainees can be identified. By targeting these errors, training programs can improve the quality and relevance of the education they provide.

Child↗

PubMed2004

Twenty-four-hour ambulatory blood pressure in children with sleep-disordered breathing.

Obstructive sleep apnea causes intermittent elevation of systemic blood pressure (BP) during sleep. To determine whether obstructive apnea in children has a tonic effect on diurnal BP, 24-hour ambulatory blood pressure was obtained from 60 children with mean age of 10.8 +/- 3.5 years. Thirty-nine children had obstructive apnea and 21 had primary snoring. Children with obstructive apnea had significantly greater mean BP variability during wakefulness and sleep, a higher night-to-day systolic BP, and a smaller nocturnal dipping of mean BP. Variability of mean arterial pressure during wakefulness was predicted by the desaturation, body mass, and arousal indices, whereas variability during sleep was predicted by apnea-hypopnea and body mass indices. Nocturnal BP dipping was predicted by the desaturation index. There were no significant differences in systolic, diastolic, or mean arterial BP during sleep between the groups. Diastolic BP during wakefulness was significantly different between the groups and correlated negatively with apnea-hypopnea index. We conclude that obstructive apnea in children is associated with 24-hour BP dysregulation and that, independent of obesity, the frequency of obstructive apnea, oxygen desaturation, and arousal contributes to abnormal BP control.

Adolescent↗

PubMed2004

High-resolution computed tomography in young patients with cystic fibrosis: distribution of abnormalities and correlation with pulmonary function tests.

OBJECTIVE: To assess pulmonary abnormalities detected by high-resolution computed tomography (HRCT) in young children with cystic fibrosis (CF) and mild to moderate lung disease. STUDY DESIGN: High-resolution computed tomography was performed in 60 children, 6 to 10 years old, with mild to moderate lung disease (forced expiratory volume in 1 minute [FEV(1)], 52-137; mean, 102; SD, 15% predicted). HRCTs were scored by using a system that evaluates each lobe for severity and extent of CF lung disease. Findings of CF lung disease were tabulated in all subjects and in a subgroup with normal pulmonary function tests. HRCT scores were correlated with FEV(1), forced vital capacity (FVC), and forced expiratory flow between 25% and 75% of expired vital capacity (FEF(25-75)) in 57 patients. RESULTS: Bronchiectasis was present in 35% of subjects, mucous plugging in 15%, and air trapping in 63%. No abnormality was detected in 25%. In 37 subjects with FEV(1), FVC, and FEF(25-75) >85% predicted, bronchiectasis was present in 30%. In 17% of these subjects, bronchiectasis was seen in > or =4 lobes. Correlations between HRCT scores and FEV(1) were significant and showed fair to moderate correlation (r=0.36-0.46). CONCLUSIONS: High-resolution computed tomography demonstrated a broad range of pulmonary abnormalities in young patients with CF with mild to moderate lung disease. In this study, abnormalities, including bronchiectasis, were common in young children with CF and normal pulmonary function tests.

Bronchiectasis↗

PubMed2004

Intranasal administration of an Escherichia coli-expressed codon-optimized rotavirus VP6 protein induces protection in mice.

We are developing rotavirus vaccines based on the VP6 protein of the human G1P[8] [corrected] [J. Virol. 73 (1999) 7574] CJN strain of rotavirus. One prototype candidate consisting of MBP::VP6::His6, a chimeric protein of maltose-binding protein, VP6 and hexahistidine, was expressed mainly as truncated polypeptides in Escherichia coli BL21(DE3) cells. A possible reason for this extensive truncation is the high frequencies of rare bacterial codons within the rotavirus VP6 gene. Expression of truncated recombinant VP6 was found to be reduced, and expression of complete VP6 protein was simultaneously increased, when the protein was expressed in Rosetta(DE3)pLacI E. coli cells that contain increased amounts of transfer RNAs for a selection of rare codons. The same observation was made when a synthetic codon-optimized CJN-VP6 gene was expressed in E. coli BL21 or Rosetta cells. To increase protein recovery, recombinant E. coli cells were treated with 8M urea. Denatured, full-length MBP::VP6::His6 protein was then purified and used for intranasal vaccination of BALB/c mice (2 doses administered with E. coli heat-labile toxin LT(R192G) as adjuvant). Following oral challenge with the G3P[16] [corrected] [J. Virol. 76 (2002) 560] EDIM strain of murine rotavirus, protection levels against fecal rotavirus shedding were comparable (P>0.05) between groups of mice immunized with denatured codon-optimized or native (not codon-optimized) immunogen with values ranging from 87 to 99%. These protection levels were also comparable to those found after immunization with non-denatured CJN VP6. Thus, expression of complete rotavirus VP6 protein was greatly enhanced by codon optimization, and the protection elicited was not affected by denaturation of recombinant VP6.

Administration, Intranasal↗

PubMed2004

Blood pressure response to melatonin in type 1 diabetes.

HYPOTHESIS: Diminished decline of blood pressure at night has been associated with increased risk of cardiovascular disease. Exogenous melatonin given to healthy normotensive adults reduces blood pressure. We hypothesized that melatonin increases the decline of blood pressure during sleep in normotensive adolescents with type 1 diabetes. PATIENTS AND METHODS: Eleven normotensive normoalbuminuric patients with type 1 diabetes of 7.0 +/- 3.5 yr duration and 10 healthy controls aged 14-18 yr participated in a randomized placebo-controlled double-blind crossover study of 5 mg melatonin for 1 wk, with a 1-wk washout. Blood pressure was measured every 20 min for 24 h by an ambulatory device on the day before and on the last day of each treatment. Sleep measures were recorded by a diary and a wrist activity meter. Blood pressure measures were grouped by 24 h, sleep, and wake periods. Statistical analysis used sleep duration, number of awakenings, and treatment sequence as covariates for the blood pressure comparisons by treatment. RESULTS: In the patients with type 1 diabetes, the decline in diastolic blood pressure during sleep was significantly greater on melatonin (17.8 +/- 4.4 mmHg) than on placebo (16.0 +/- 3.0 mmHg, p < 0.01). No significant drug effect was present in the controls. No significant side effects were noted. CONCLUSION: Melatonin amplifies the nocturnal decline in diastolic blood pressure in patients with type 1 diabetes. We propose that dose-response studies of short- and long-acting preparations of melatonin be conducted and that melatonin be considered in trials of prevention of hypertension in type 1 diabetes.

Adolescent↗

PubMed2004

Blood pressure-lowering effect of melatonin in type 1 diabetes.

Our long-term goal is to determine the utility of melatonin in prevention of hypertension in type 1 diabetes. We recently reported that 5 mg melatonin taken at bedtime increases the nocturnal drop of diastolic blood pressure (BP) in adolescents with type 1 diabetes. The present study tested the hypothesis that a higher dose of melatonin, 10 mg, lowers both systolic and diastolic BP in these patients. The design was an open-label trial of 10 mg melatonin taken at bedtime daily for 7 days. Nine normotensive adolescents with type 1 diabetes, 16.2 +/- 0.3 yr old, and eight healthy controls, 16.6 +/- 0.6 yr old participated. BP was measured every 20 min by ambulatory monitoring device for 24 hr before treatment onset and on the last treatment day; sleep was monitored by diary and wrist actigraphy. Outcome measures were BP during wake, sleep and over a 24-hr period. Sleep duration and number of awakenings were used as covariates. Significance for this pilot study was set at P < 0.10. In patients with diabetes the mean BP during sleep was lower on melatonin than before treatment: systolic 104.0 +/- 2.4 and 108.4 +/- 2.4 mmHg (P = 0.085) and diastolic, 57.1 +/- 1.9 and 59.3 +/- 1.9 mmHg (P = 0.079), respectively. In controls there was no significant effect of melatonin on BP. There was no significant effect of sleep duration or number of awakenings on the BP responses. We conclude that the present results justify phase III therapeutic trials to determine the utility of melatonin in prevention of hypertension and cardiovascular complications in type 1 diabetes.

Adolescent↗