An exploratory analysis of occupational skin disease among Latino migrant and seasonal farmworkers in North Carolina.

Occupational skin disease is highly prevalent among all agricultural workers. However, few data exist on risk factors for occupational skin disease among migrant and seasonal farmworkers. The goal of this analysis was to further document the prevalence of occupational skin disease among Latino farmworkers and delineate risk factors. This exploratory analysis used data collected in repeated survey interviews with Latino farmworkers in North Carolina in June and July (early season) and in August and September (late season), 1999. Respondents were largely male (95%) and from Mexico (95%), with about one-third each age 18-24, 25-34, and 35 and older. About half were in the U.S. on work contracts. Independent variables included the physical environment (crops worked), the social environment (having received pesticide safety training, having a work contract), and behavior and individual characteristics (re-wearing work clothes, showering after work, age). The dependent measures were reporting having had itching or burning skin or a skin rash in the two months prior to each interview; 24% of the respondents in the early season, and 37% in the late season reported skin disease signs and symptoms during the previous two months. Those reporting signs and symptoms in the early season were more likely to report them in late season. Significant independent risk factors for skin signs and symptoms in early season were re-wearing work clothes, showering after work, and being age 35 or older. In late season, those who had not received pesticide safety training had lower odds of reporting skin disease signs and symptoms, after adjusting for other potential risk factors. This exploratory study indicates that Latino migrant and seasonal farmworkers experience a high incidence of occupational skin disease. Further research is required with improved measurement of skin disease signs and symptoms, diagnosis of specific skin disease, and improved measurement of risk factors.

Postnatal dexamethasone treatment and retinopathy of prematurity in very-low-birth-weight neonates.

Whether postnatal dexamethasone treatment for bronchopulmonary dysplasia (BPD) increases the risk of retinopathy of prematurity (ROP) in very-low-birth-weight (VLBW) neonates is uncertain. We performed a retrospective cohort study to determine the association between dexamethasone administered postnatally and the development of ROP in VLBW (< or = 1,250 g birth weight, < or = 32 weeks' gestational age at birth) neonates. The incidence of severe ROP (stage 2 or higher) was 26% among 72 infants who received no dexamethasone postnatally, 61% among 23 infants who received a low cumulative dexamethasone dose (< or = 1.8 mg/kg body weight), and 85% among 20 infants who received a high cumulative dexamethasone dose (> 1.8 mg/kg body weight). However, after adjustment for confounding covariates of prematurity and severity of lung disease by logistic regression analysis, we found no independent association between postnatal dexamethasone treatment and the incidence of severe ROP.

The efficacy of 308nm laser treatment of psoriasis compared to historical controls.

UVB treatment with a 308nm excimer laser has shown promise in the treatment of localized psoriasis. There is no placebo or comparison treatment controlled trial studying efficacy of the laser, however. The purpose of this report is to compare the results of a study of 308nm laser treatment of psoriasis to published results of other psoriasis treatments. Data on the efficacy of 308nm laser treatment of psoriasis were obtained from a previously published case series, supplemented by reanalysis of the data to estimate the median time to success using Kaplan-Meier methods. These results were compared to those from other studies identified by a Medline search. Treatment success was measured by estimating the percentage of patients who achieve 75% improvement in the severity of psoriasis. Patients treated in the 308nm laser study had similar disease severity as those in topical treatment studies and less severe disease than those treated in studies using standard phototherapy or systemic therapy. A greater percentage of patients achieved 75% improvement with the UVB laser treatments than was reported for other forms of phototherapy or systemic therapy with acitretin or low dose cyclosporine, and did so more rapidly. The UVB laser study patients achieved the 75% improvement endpoint in an average of 46% fewer treatments than was observed in other phototherapy studies. Laser treatment and topical calcipotriene had similar efficacies, and both were more effective than topical tazarotene or topical fluocinonide. As compared to topical therapies, the time to achieve 75% improvement favored the UVB laser. 308nm laser treatments for psoriasis are clearly more effective than placebo and are comparable to or more effective than many other standard treatments for psoriasis.

Rates of hospitalization for respiratory syncytial virus infection among children in medicaid.

OBJECTIVE: To determine rates of hospitalization associated with respiratory syncytial virus (RSV) infection among children with and without specific medical conditions. STUDY DESIGN: Retrospective cohort study of all children <3 years old enrolled in the Tennessee Medicaid program from July 1989 through June 1993 (248,652 child-years). RESULTS: During the first year of life, the estimated number of RSV hospitalizations per 1000 children was 388 for those with bronchopulmonary dysplasia, 92 for those with congenital heart disease, 70 for children born at < or = 28 weeks' gestation, 66 for those born at 29 to <33 weeks, 57 for those born at 33 to <36 weeks, and 30 for children born at term with no underlying medical condition. In the second year of life, children with bronchopulmonary dysplasia had an estimated 73 RSV hospitalizations per 1000 children, whereas those with congenital heart disease had 18 and those with prematurity 16 per 1000. Overall, 53% of RSV hospitalizations occurred in healthy children born at term. CONCLUSIONS: Children with bronchopulmonary dysplasia have high rates of RSV hospitalization until 24 months of age. In contrast, after the first year of life, children with congenital heart disease or prematurity have rates no higher than that of children at low risk who are <12 months old.

Vitamin A status and postnatal dexamethasone treatment in bronchopulmonary dysplasia.

OBJECTIVE: Vitamin A (retinol) plays an important role in epithelial regeneration during recovery from lung injury in bronchopulmonary dysplasia (BPD). Dexamethasone is used in the postnatal treatment of very low birth weight (VLBW) neonates with BPD. To test the hypothesis that the vitamin A status is critical for the beneficial pulmonary response to dexamethasone, we performed a prospective cohort study in which we characterized the changes in plasma concentrations of vitamin A and retinol-binding protein (RBP) in response to dexamethasone, and correlated these changes with the pulmonary outcome. METHODS: VLBW neonates (birth weight <1350 g, gestational age <31 weeks, postnatal age >10 days), who had presumptive diagnosis of severe BPD and need for high ventilatory support (fraction of inspired oxygen >/=.6, mean airway pressure >/=7 cm H(2)O), were treated with a seven-day course of dexamethasone (.5 mg/kg/d x 2 days,.25 mg/kg/d x 2 days,.1 mg/kg/d x 3 days). Plasma concentrations of vitamin A and RBP were determined sequentially at baseline, and during and after dexamethasone treatment. Pulmonary response to dexamethasone was graded daily using a composite ventilation score. The changes in plasma vitamin A and RBP concentrations were compared between infants with a positive (beneficial) pulmonary response to dexamethasone and those with a negative response. RESULTS: Among 23 infants studied, 13 showed a positive pulmonary response to dexamethasone, as indicated by successful weaning from supplemental oxygen and mechanical ventilation, whereas 10 showed a negative response. A significant, yet short-term, increase in plasma concentrations of both vitamin A and RBP was observed in most infants treated with dexamethasone. The plasma vitamin A and RBP responses to dexamethasone tended to be higher in infants with a positive pulmonary response than in those with a negative response. Accounting for gender, a vitamin A response with each 10.0 microg/dL increment in plasma vitamin A concentration was associated with a 60% increase in the odds favoring a positive pulmonary response to dexamethasone. CONCLUSION: Postnatal dexamethasone treatment in VLBW neonates with BPD induces a significant, yet short-term, increase in plasma concentrations of both vitamin A and RBP. This increase probably results from endogenous mobilization of vitamin A from the liver. Our data suggest that the beneficial pulmonary response to dexamethasone in infants with BPD is influenced, at least in part, by the vitamin A status, and that gender plays a role in this response.vitamin A, dexamethasone, bronchopulmonary dysplasia.

Mechanical vibration in neonatal transport: a randomized study of different mattresses.

OBJECTIVE: To test the hypothesis that a gel mattress is most effective in attenuating mechanical vibration in neonatal transport, we performed a randomized block study of four mattress combinations (none, foam, gel, gel on foam) using mannequins and an ambulance traveling on fixed routes (city, highway). STUDY DESIGN: Mechanical vibration was assessed by measuring vertical accelerations at two locations: the forehead of a 2000-gm mannequin and the transport incubator base. From time histories of these accelerations, root mean square (RMS) values and power spectral density functions were calculated. The effect of the mattress on the transmission of vibration was determined from ratios of the RMS values at the two locations. An RMS ratio of < 1.0 indicates attenuation, whereas a ratio of > 1.0 indicates accentuation of vibration. From the power spectral density functions, the natural frequency of the system was determined for each mattress combination in relation to the natural frequencies of the ambulance. To determine the effect of the weight of the mannequin on vibration, additional measurements were performed using a 300-gm mannequin. RESULTS: All the observed RMS ratios were > 1. The highest ratios were observed on the city route in the absence of the gel mattress. The gel mattress, used alone or with the foam mattress, in contrast to foam or no mattress, shifted the natural frequency of the system away from the natural frequencies of the ambulance, avoiding a large amplification of vibration. A decrease in the weight of the mannequin caused the gel mattress to be less effective in attenuating vibration. CONCLUSION: A gel mattress, used alone or with a foam mattress, results in the least accentuation of vibration, but vibration in ambulance transport is not attenuated by any of the mattress combinations. The hazard of vibration may be particularly relevant when transporting extremely low birth weight neonates. These findings indicate a need for study and design of more effective devices that can reduce the vibratory stress.

Prostaglandin E(2) decreases allergen-stimulated release of prostaglandin D(2) in airways of subjects with asthma.

Prostaglandin E(2) (PGE(2)) inhibits the early and late bronchoconstrictor response to inhaled allergen. The mechanisms of action, however, are not understood. We investigated the effect of inhaled PGE(2) on the release of prostaglandin D(2) (PGD(2)), preformed mast cell mediators, and other products of arachidonic acid metabolism. We compared inhaled PGE(2) (100 microgram) to placebo in a randomized double-blind crossover study. Ten atopic asthmatics underwent bronchoscopy immediately after inhalation of PGE(2) or placebo. Bronchoalveolar lavage (BAL) was performed at baseline, and in a separate segment 4 min after allergen instillation. Nebulized PGE(2) was well tolerated. PGE(2) concentrations in baseline lavage fluid were significantly greater after PGE(2) inhalation than after placebo. PGD(2) concentrations after allergen challenge were significantly reduced in those subjects receiving nebulized PGE(2) compared with control subjects. We conclude that PGE(2) can be safely delivered by inhalation. Nebulized PGE(2) administered before to segmental allergen challenge reduced PGD(2) in BAL fluid (BALF). PGE(2) also decreased the production of other mediators of the arachidonic acid pathway, although not significantly. The reduction of PGD(2) may be part of the mechanism by which PGE(2) blocks the early asthmatic response.

Long-term outcome in congenitally corrected transposition of the great arteries: a multi-institutional study.

OBJECTIVES: The purpose of this study was to determine long-term outcome in adults with congenitally corrected transposition of the great arteries (CCTGA), with particular emphasis on systemic ventricular dysfunction and congestive heart failure (CHF). BACKGROUND: Patients with CCTGA have the anatomical right ventricle as their systemic pumping chamber, with ventricular dysfunction and CHF being relatively common in older adults. METHODS: Retrospective analysis of records of 182 patients from 19 institutions were reviewed to determine current status and possible risk factors for systemic ventricular dysfunction and CHF. Factors considered included age, gender, associated cardiac defects, operative history, heart block, arrhythmias and tricuspid (i.e., systemic atrioventricular) regurgitation (TR). RESULTS: Both CHF and systemic ventricular dysfunction were common in groups with or without associated cardiac lesions. By age 45, 67% of patients with associated lesions had CHF, and 25% of patients without associated lesions had this complication. The rates of systemic ventricular dysfunction and CHF were higher with increasing age, the presence of significant associated cardiac lesions, history of arrhythmia, pacemaker implantation, prior surgery of any type, and particularly with tricuspid valvuloplasty or replacement. Aortic regurgitation (a previously unreported problem) was also relatively common in this patient population. CONCLUSIONS: Patients with CCTGA are increasingly subject to CHF with advancing age; this complication is extremely common by the fourth and fifth decades. Tricuspid (systemic atrioventricular) valvular regurgitation is strongly associated with RV (anatomical right ventricle connected to aorta in CCTGA patients; systemic ventricle in CCTGA) dysfunction and CHF; whether it is causative or a secondary complication remains speculative.

Underutilization of controller and rescue medications among older adults with asthma requiring hospital care.

BACKGROUND: Asthma causes serious morbidity in older people, but pharmacologic therapy in older people with asthma has never been studied, at least in part because of the difficulty of defining asthma in this population. OBJECTIVE: To determine if older persons enrolled in Medicaid and hospitalized with an exacerbation of asthma receive appropriate outpatient asthma care. DESIGN: Descriptive pharmacoepidemiology of a group of older adults with asthma. SETTING: The Tennessee Medicaid Program. PARTICIPANTS: Persons aged 65 and older, enrolled in the Tennessee Medicaid program, identified through Medicaid's computerized database as having a hospital care visit for asthma in 1992 and who had their diagnosis confirmed by chart review. MEASUREMENT: Medication utilization. RESULTS: The source population included 93,686 persons aged 65 or older enrolled in the Tennessee Medicaid program. The group meeting study criteria included 512 patients with chronic asthma who had a hospital care visit for an asthma exacerbation. Eighty-one percent of these 512 persons with an asthma hospitalization confirmed by chart review were classified as having moderate to severe or potentially fatal asthma. These patients had had a median of 15 outpatient visits in the previous year, and more than half of them had an outpatient visit in the 14 days before their hospitalization. However, among those with moderate to severe or near fatal asthma only 25% filled prescriptions for inhaled corticosteroids, whereas 52% were taking theophylline, the most commonly prescribed asthma medication in this group. There was also high use of antibiotics (29%) and low use of rescue corticosteroids (5%) before the hospital care visit, despite frequent medical encounters. CONCLUSIONS: Despite widespread promulgation of the National Asthma Education Prevention Program guidelines, our study suggests that providers caring for indigent older subjects with moderate to severe or potentially fatal asthma were not following these guidelines. There was significant underutilization of inhaled anti-inflammatory agents, beta-agonists, and rescue corticosteroids in this population despite frequent outpatient medical care visits.

Plasma leptin association with body composition and energy expenditure in sickle cell disease.

OBJECTIVE: To examine the association between fasting plasma leptin concentrations and the hypercatabolic state observed in sickle cell disease (SCD). METHODS: Plasma leptin concentration and resting energy expenditure (REE) were measured in 37 SCD patients (10 men, 12 boys 14 to 18 years-old, seven women, and eight girls 14 to 18 year-old) and in 37 age, gender and fat mass (FM) matched controls. Body composition was measured hydrostatically, REE by whole room-indirect calorimeter, and plasma leptin using an RIA kit. RESULTS: Plasma leptin concentration and leptin normalized for body fat (ng/dL*kg FM(-1)) were significantly lower in SCD patients than in non-SCD controls (4.00+/-3.23 vs. 9.94+/-14.69, p=0.021 and 0.406+/-0.260 vs. 0.643+/-0.561, p=0.024, respectively). A positive linear association between log plasma leptin and FM was observed in both males and females, adjusting for age and SCD status. The strength of this association was greater in females compared with males (slope=0.699 and 0.382 log ng/mL per 10 kg FM, respectively; p=0.013). SCD patients on average demonstrated a higher REE, adjusting for FFM (p<0.0001). Log plasma leptin and FM were not statistically significant predictors of REE after adjustment for FFM and SCD. CONCLUSIONS: Once corrected for body composition, mean plasma leptin concentration was significantly lower among female SCD patients than among non-SCD matched controls. Although REE was higher in SCD patients, there is no simple association between leptin and REE in SCD.

The effect of influenza on hospitalizations, outpatient visits, and courses of antibiotics in children.

BACKGROUND: Despite high annual rates of influenza in children, influenza vaccines are given to children infrequently. We measured the disease burden of influenza in a large cohort of healthy children in the Tennessee Medicaid program who were younger than 15 years of age. METHODS: We determined the rates of hospitalization for acute cardiopulmonary conditions, outpatient visits, and courses of antibiotics over a period of 19 consecutive years. Using the differences in the rates of these events when influenzavirus was circulating and the rates from November through April when there was no influenza in the community, we calculated morbidity attributable to influenza. There was a total of 2,035,143 person-years of observation. RESULTS: During periods when influenzavirus was circulating, the average number of hospitalizations for cardiopulmonary conditions in excess of the expected number was 104 per 10,000 children per year for children younger than 6 months of age, 50 per 10,000 per year for those 6 months to less than 12 months, 19 per 10,000 per year for those 1 year to less than 3 years, 9 per 10,000 per year for those 3 years to less than 5 years, and 4 per 10,000 per year for those 5 years to less than 15 years. For every 100 children, an annual average of 6 to 15 outpatient visits and 3 to 9 courses of antibiotics were attributable to influenza. In winter, 10 to 30 percent of the excess number of courses of antibiotics occurred during periods when influenzavirus was circulating. CONCLUSIONS: Healthy children younger than one year of age are hospitalized for illness attributable to influenza at rates similar to those for adults at high risk for influenza. The rate of hospitalization decreases markedly with age. Influenza accounts for a substantial number of outpatient visits and courses of antibiotics in children of all ages.

Creamatocrit and the nutrient composition of human milk.

OBJECTIVE: We tested the hypothesis that creamatocrit, the length of the cream column separated from milk by centrifugation and expressed as a percentage of the length of the total milk column, is a useful measure of the lipid concentration and the energy content of human milk. STUDY DESIGN: Milk samples from 17 mothers of preterm infants were analyzed prospectively, fresh as well as frozen and thawed, for creamatocrit measurement and nutrient composition. RESULTS: Creamatocrit correlated strongly with lipid concentration and energy content of human milk, fresh or frozen and thawed. The energy content can be calculated from the regression equation: Energy (kcal/dl) = 5.99 x creamatocrit(%) + 32.5 for a fresh sample, and energy (kcal/dl) = 6.20 x creamatocrit(%) + 35.1 for a frozen sample. CONCLUSION: Calculations of energy content from the creamatocrit measurement may be useful for an accurate assessment of energy intake in preterm infants fed human milk.

Plasma concentrations of immunoreactive atrial natriuretic peptide in hospitalized cirrhotic and noncirrhotic patients: evidence for a role of deficient atrial natriuretic peptide in pathogenesis of cirrhotic ascites.

Atrial natriuretic peptide(s) (ANP), are thought to be released from the cardiac atria in response to distension. If decreased effective circulating blood volume is important in pathogenesis of ascites, plasma ANP levels would be expected to be decreased in ascitic subjects because of decreased atrial distension. To test this hypothesis, we measured plasma ANP by competitive radioimmunoassay in three groups of fasted, supine hospitalized subjects: nine noncirrhotic control subjects, 12 cirrhotics without ascites, and 17 cirrhotics with moderate to marked ascites. Immunoreactive plasma ANP concentrations were 195 +/- 41, 171 +/- 31, and 137 +/- 34 pg/ml (m +/- SD), respectively, in the three groups. The mean concentration in the group with cirrhosis and ascites was significantly (p less than or equal to 0.01) les than those of the other two groups, which did not differ from one another. These results support the concept that decreased effective circulating volume plays a role in pathogenesis of cirrhotic ascites, and that a relative deficiency of ANP plays a role in the sodium retention of decompensated cirrhosis.

Testing for developmental changes in gene expression on resemblance for quantitative traits in kinships of twins: application to height, weight, and blood pressure.

Height, weight, and blood pressure measurements on identical and fraternal twins and their families were analyzed to assess the degree to which genetic effects may change with age. The blood pressure data were based on the total sample of 1,767 individuals, while height and weight were available on 1,640 individuals in 204 monozygotic twin kinships. The results of testing alternative hypotheses about developmental changes in gene expression indicate that different mechanisms may be operative for these traits. While there was no evidence that developmental effects are a significant source of the observed variation in systolic or diastolic blood pressure, there was strong evidence that genetically determined developmental changes are an important factor in the determination of body weight. Age-related changes in weight appeared to be best explained by the cumulative developmental effects of a single set of genes, rather than by the expression of new genes at different stages of development.