Effect of Avoiding Cow's Milk Formula at Birth on Prevention of Asthma or Recurrent Wheeze Among Young Children: Extended Follow-up From the ABC Randomized Clinical Trial.

Importance: Children with food allergies may develop asthma or recurrent wheeze. Objective: To evaluate whether asthma or recurrent wheeze among children were changed by avoiding supplementing breastfeeding (BF) with cow's milk formula (CMF) in the first 3 days of life. Design, Setting, and Participants: This randomized, unmasked, clinical trial was conducted at 1 university hospital in Japan beginning October 2013 with follow-up examinations occurring until January 2020. A total of 312 newborns at risk for atopy were randomized and assigned to either BF with or without amino acid-based elemental formula (EF) or BF with CMF, with follow-up examinations for participants showing signs of atopy conducted at 24 months. Follow-up examinations ran through January 2020. Interventions: Immediately after birth, newborns were randomly assigned (1:1 ratio) to either breastfeeding with or without amino acid-based elemental formula for at least the first 3 days of life (no CMF group) or breastfeeding supplemented with CMF (≥5 mL/d) from the first day of life to 5 months of age (CMF group). Main Outcomes and Measures: Asthma or recurrent wheeze diagnosed by the pediatric allergy specialists of this trial; subgroups were stratified by serum levels of 25-hydroxyvitamin D and IgE. Results: Of 312 infants (156 [50.0%] randomized to the no CMF group), 302 (96.8%) were followed up at their second birthday: 77 of 151 (51.0%) in the no CMF group and 81 of 151 (53.6%) in the CMF group underwent extended follow-up because of having atopic conditions. Asthma or recurrent wheeze developed in 15 (9.9%) of the children in the no CMF group, significantly less than the children in the CMF group (27 [17.9%]; risk difference, -0.079; 95% CI, -0.157 to -0.002). In participants with vitamin D levels above the median at 5 months of age, asthma or recurrent wheeze developled in 5 (6.4%) children in the no CMF group, significantly less than in the children in the CMF group (17 [24.6%]; risk difference, -0.182; 95% CI, -0.298 to -0.067; P for interaction = .04). In the highest quartile group of total IgE at age 24 months, asthma or recurrent wheeze developed in 2 children (5.3%) in the no CMF group, significantly less than the children in the CMF group (14 [43.8%]; risk difference, -0.385; 95% CI, -0.571 to -0.199; P for interaction = .004). Conclusions and Relevance: The findings of this study suggest that avoiding CMF supplementation in the first 3 days of life has the potential to reduce the risk of asthma or recurrent wheeze in young children, especially among those with high vitamin D or high IgE levels. Trial Registration: umin.ac.jp/ctr Identifier: UMIN000011577.

Outcomes of Paradoxical Vocal Cord Motion Diagnosed in Childhood.

OBJECTIVES: To explore long-term patient reported outcome (PRO) measures of pediatric paradoxical vocal cord motion (PVCM) including ease of diagnosis, management, symptom duration and effect on quality of life. METHODS: All children >8 years of age diagnosed with PVCM at a tertiary pediatric hospital between 2006 and 2017 were invited to complete a survey addressing study objectives. RESULTS: 21/47 eligible participants could be contacted and 18/21 (86%) participated. 78% were female with a mean age at diagnosis of 11.6 and 15.0 years at survey completion. Common PVCM symptoms reported were dyspnea (89%), globus sensation (56%), and stridor (50%). The median time to diagnosis was 3 months (IQR 2-5 months). Nearly all reported being misdiagnosed with another condition, usually asthma, until being correctly diagnosed usually by an otolaryngologist. Participants reported undergoing 3.7 diagnostic studies (range 0-8); pulmonary function testing was most common. Of numerous treatments acknowledged, breathing exercises were common (89%) but only reported helpful by 56%. Use of biofeedback was recalled in 1/3 of subjects but reported helpful in only 14% of them. Anti-reflux, allergy, anticholinergics, inhalers and steroids were each used in >50%, but rarely reported effective. PVCM was reportedly a significant stressor when initially diagnosed but despite 2/3 of participants still reporting ongoing PVCM symptoms, the perceived stress significantly decreased over time (Z = 3.26, P = 0.001). CONCLUSIONS: This first PVCM PRO study endorses that diagnosis is often delayed and prescribed treatments often viewed as ineffective. While biofeedback and breathing exercises may be critical for short-term control of PVCM episodes, lifestyle changes and stress reduction are likely necessary for long-term management. Increased awareness and improvements in management are needed for this condition.

Oximetry-detected pulsus paradoxus predicts for severity in paediatric asthma.

OBJECTIVE: To evaluate if qualitative visual detection of pulsus paradoxus (PP) on the pulse oximeter plethysmograph can predict outcomes for children with moderate to severe respiratory distress in a paediatric emergency department (ED). DESIGN: Prospective cohort study. SETTING: Paediatric ED of a tertiary paediatrics hospital in Singapore. PATIENTS: Children managed for moderate to severe wheezing in the resuscitation bay of the ED. INTERVENTIONS: Patients were assessed for the presence of PP based on visual detection of oximeter plethysmograph before and after initial inhaled bronchodilator therapy. MAIN OUTCOME MEASURES: These include the need for adjunct medications such as aminophylline or magnesium sulfate, the need for supplementary ventilation and the need for admission to the high dependency unit (HDU) or intensive care unit (ICU). RESULTS: There were 285 patients included in the study, of whom 78 (27.4%) had PP at ED presentation. There were 40 (14.0%) who had PP after initial management. Children who had PP after initial management had significantly relative risks (RR) of requiring adjunct medications (RR 12.5, 95% CI 4.0 to 38.6), need for supplementary ventilation (RR 5.6, 95% CI 1.2 to 26.5) and admission to the HDU/ICU (RR 5.6, 95% CI 3.0 to 10.4). CONCLUSION: Qualitative detection of PP on pulse oximetry can be used as a potential point-of-care tool to help in the assessment of response to initial treatment in paediatric patients with acute moderate to severe asthma exacerbations. Future studies are needed to assess and validate its role in guiding ED management of acute paediatric asthma.

Diagnosis of asthma in children: the contribution of a detailed history and test results.

INTRODUCTION: There are few data on the usefulness of different tests to diagnose asthma in children. AIM: We assessed the contribution of a detailed history and a variety of diagnostic tests for diagnosing asthma in children. METHODS: We studied children aged 6-16 years referred consecutively for evaluation of suspected asthma to two pulmonary outpatient clinics. Symptoms were assessed by parental questionnaire. The clinical evaluation included skin-prick tests, measurement of exhaled nitric oxide fraction (F eNO), spirometry, bronchodilator reversibility and bronchial provocation tests (BPT) by exercise, methacholine and mannitol. Asthma was diagnosed by the physicians at the end of the visit. We assessed diagnostic accuracy of symptoms and tests by calculating sensitivity, specificity, positive and negative predictive values and area under the curve (AUC). RESULTS: Of the 111 participants, 80 (72%) were diagnosed with asthma. The combined sensitivity and specificity was highest for reported frequent wheeze (more than three attacks per year) (sensitivity 0.44, specificity 0.90), awakening due to wheeze (0.41, 0.90) and wheeze triggered by pollen (0.46, 0.83) or by pets (0.29, 0.99). Of the diagnostic tests, the AUC was highest for F eNO measurement (0.80) and BPT by methacholine (0.81) or exercise (0.74), and lowest for forced expiratory volume in 1 s (FEV1) (0.62) and FEV1/forced vital capacity ratio (0.66), assessed by spirometry. CONCLUSION: This study suggests that specific questions about triggers and severity of wheeze, measurement of F eNO and BPT by methacholine or exercise contribute more to the diagnosis of asthma in school-aged children than spirometry, bronchodilator reversibility and skin-prick tests.

Do clinical investigations predict long-term wheeze? A follow-up of pediatric respiratory outpatients.

INTRODUCTION: The contribution of clinical investigations to prediction of long-term outcomes of children investigated for asthma is unclear. AIM: We performed a broad range of clinical tests and investigated whether they helped to predict long-term wheeze among children referred for evaluation of possible asthma. METHODS: We studied children aged 6 to 16 years referred to two Swiss pulmonary outpatient clinics with a history of wheeze, dyspnea, or cough in 2007. The initial assessment included spirometry, fractional exhaled nitric oxide, skin prick tests, and bronchial provocation tests by exercise, methacholine, and mannitol. Respiratory symptoms were assessed with questionnaires at baseline and at follow-up 7 years later. Associations between baseline factors and wheeze at follow-up were investigated by logistic regression. RESULTS: At baseline, 111 children were examined in 2007. After 7 years, 85 (77%) completed the follow-up questionnaire, among whom 61 (72%) had wheeze at baseline, while at follow-up 39 (46%) reported wheeze. Adjusting for age and sex, the following characteristics predicted wheeze at adolescence: wheeze triggered by pets (odds ratio, 4.2; 95% CI, 1.2-14.8), pollen (2.8, 1.1-7.0), and exercise (3.1, 1.2-8.0). Of the clinical tests, only a positive exercise test (3.2, 1.1-9.7) predicted wheeze at adolescence. CONCLUSION: Reported exercise-induced wheeze and wheeze triggered by pets or pollen were important predictors of wheeze persistence into adolescence. None of the clinical tests predicted wheeze more strongly than reported symptoms. Clinical tests might be important for asthma diagnosis but medical history is more helpful in predicting prognosis in children referred for asthma.

Vitamin D and respiratory health in the Busselton Healthy Ageing Study.

BACKGROUND AND OBJECTIVE: The relationship between vitamin D and respiratory disease was examined by cross-sectional analysis of a large community-based sample. METHODS: Serum 25-hydroxyvitamin D (25OHD) and history of respiratory disease, symptoms (recorded by questionnaire) and spirometry were measured in 5011 adults aged 45-69 years. Adjustments were made for age, sex, season and smoking (Model A), plus body mass index (BMI) and physical activity level (Model B), plus history of chronic diseases (Model C). RESULTS: Mean (SD) age was 58 (SD 6) years with 45% males, 10% current smokers and 12% taking vitamin D supplements. The prevalence of 25OHD level <50 nmol/L was 8.0%. In all the three models, 25OHD <50 nmol/L was significantly associated with asthma (Model C: odds ratio (OR): 1.32; 95% CI: 1.00, 1.73), bronchitis (1.54; 1.17, 2.01), wheeze (1.37; 1.10, 1.71) and chest tightness (1.42; 1.10, 1.83). Participants with vitamin D level > 100 nmol/L had higher forced vital capacity (FVC) in all the three models (1.17% higher, compared with the 50-100 nmol/L group in Model C). CONCLUSION: Low levels of serum 25OHD were independently associated with asthma, bronchitis, wheeze and chest tightness after three levels of adjustment for potential confounders. Higher vitamin D levels were associated with higher levels of lung function.

Serum 25-hydroxyvitamin D levels in children with recurrent wheezing and relation to the phenotypes and frequency of wheezing.

SUMMARY: Background. Recurrent wheezing may be related to various reasons. There is a lack of knowledge about the effect of vitamin D status in the children with recurrent wheezing. The aim of this study is to compare the level of vitamin D between recurrent wheezing children and healthy controls, and to investigate the relationship between vitamin D status and the clinical parameters of recurrent wheezing in preschool children. Methods. One hundred-ten children followed up in our hospital with recurrent wheezing were included in the study. The control group included fifty children without wheezing episodes. The serum 25-hydroxyvitamin D (25OHD) level was measured. The patients with recurrent wheezing were grouped according to their vitamin D status as "deficient group" and "non-deficient group (Vitamin D level is insufficient and normal)". We investigated the relationship between vitamin D status and the clinical and laboratory parameters of children with recurrent wheezing. Results. Mean 25OHD level was 21.66 ± 8.13 ng/mL (5.6-53) in the study group and 25.36 ± 10.17 ng/mL (6-59) in the control group. The difference was statistically significant (p = 0.015). When the patients with recurrent wheezing were compared according to their vitamin D status, number of hospitalizations, number of positive sensitivity, percentage of eosinophil, serum IgE levels, Asthma Predictive Index positivity and wheezing phenotypes were not found to be different between groups. However, the duration of wheezing, the number of wheezing episodes and systemic glucocorticoid need in the previous year, and the total number of wheezing episodes were significantly higher in the deficient group (p < 0.05). The serum 25OHD level was negatively correlated with the duration of wheezing (r: -0.238; p: 0.012), total number of wheezing episodes (r: -0.436; p: 0.001), number of wheezing episodes in the previous year (r: -0.395; p: 0.001), and systemic glucocorticoid need in the previous year (r: -0.324; p: 0.001). Conclusions. Mean 25OHD levels were lower in patients with recurrent wheezing than in healthy controls. The duration of illness and number of wheezing episodes were correlated with vitamin D levels. An evaluation of the serum levels of vitamin D and supplementation if needed should be recommended in patients with recurrent wheezing, especially in those with long-term and frequent wheezing episodes.

Infant Respiratory Tract Infections or Wheeze and Maternal Vitamin D in Pregnancy: A Systematic Review.

BACKGROUNDS: Respiratory tract infections (RTIs) are a common cause of morbidity and mortality in young children and can be associated with wheeze. Vitamin D can have a protective role against RTI. MATERIALS AND METHODS: A systematic search of PubMed, Embase and the Cochrane library was performed. Titles and abstracts were evaluated, and selected articles were reviewed by 2 authors. We included randomized controlled trials (RCTs) investigating the effect of vitamin D supplementation during pregnancy on RTIs or wheeze in children of 5 years of age or younger. Observational studies on the association between serum 25-hydroxyvitamin D during pregnancy, or at birth, and RTIs and/or wheeze were included. The protocol was registered on PROSPERO (Registration number: CRD42015019183). RESULTS: Of 4 RCTs, 1 showed a protective effect of a high daily dose (2000 IU) of vitamin D during pregnancy on offspring RTI doctor visits (P = 0.004; the RCT also included 800 IU/d supplement to the infants until 6 months). Meta-analysis of 3 RCTs showed a reduced relative risk for offspring wheeze when mothers were supplemented with vitamin D during pregnancy [relative risk: 0.81 (95% confidence interval: 0.68-0.97), P = 0.025]. In 3 of 4 strong-quality, and 5 of 10 moderate-quality observational studies, an inverse association between pregnancy and cord 25-hydroxyvitamin D and subsequent wheeze and/or RTI was seen. CONCLUSION: Growing evidence supports a preventive role of vitamin D during pregnancy on offspring wheeze and/or RTI. Recommendations in future intervention studies may need to exceed current recommendations of vitamin D supplementation during pregnancy to show benefit against childhood wheeze or infections.

Vitamin C supplementation for pregnant smoking women and pulmonary function in their newborn infants: a randomized clinical trial.

IMPORTANCE: Maternal smoking during pregnancy adversely affects offspring lung development, with lifelong decreases in pulmonary function and increased asthma risk. In a primate model, vitamin C blocked some of the in-utero effects of nicotine on lung development and offspring pulmonary function. OBJECTIVE: To determine if newborns of pregnant smokers randomized to receive daily vitamin C would have improved results of pulmonary function tests (PFTs) and decreased wheezing compared with those randomized to placebo. DESIGN, SETTING, AND PARTICIPANTS: Randomized, double-blind trial conducted in 3 sites in the Pacific Northwest between March 2007 and January 2011. One hundred fifty-nine newborns of randomized pregnant smokers (76 vitamin C treated and 83 placebo treated) and 76 newborns of pregnant nonsmokers were studied with newborn PFTs. Follow-up assessment including wheezing was assessed through age 1 year, and PFTs were performed at age 1 year. INTERVENTIONS: Pregnant women were randomized to receive vitamin C (500 mg/d) (n = 89) or placebo (n = 90). MAIN OUTCOMES AND MEASURES: The primary outcome was measurement of newborn pulmonary function (ratio of the time to peak tidal expiratory flow to expiratory time [TPTEF:TE] and passive respiratory compliance per kilogram [Crs/kg]) within 72 hours of age. Secondary outcomes included incidence of wheezing through age 1 year and PFT results at age 1 year. A subgroup of pregnant smokers and nonsmokers had genotyping performed. RESULTS: Newborns of women randomized to vitamin C (n = 76), compared with those randomized to placebo (n = 83), had improved pulmonary function as measured by TPTEF:TE (0.383 vs 0.345 [adjusted 95% CI for difference, 0.011-0.062]; P = .006) and Crs/kg (1.32 vs 1.20 mL/cm H2O/kg [95% CI, 0.02-0.20]; P = .01). Offspring of women randomized to vitamin C had significantly decreased wheezing through age 1 year (15/70 [21%] vs 31/77 [40%]; relative risk, 0.56 [95% CI, 0.33-0.95]; P = .03). There were no significant differences in the 1-year PFT results between the vitamin C and placebo groups. The effect of maternal smoking on newborn lung function was associated with maternal genotype for the α5 nicotinic receptor (rs16969968) (P < .001 for interaction). CONCLUSIONS AND RELEVANCE: Supplemental vitamin C taken by pregnant smokers improved newborn PFT results and decreased wheezing through 1 year in the offspring. Vitamin C in pregnant smokers may be an inexpensive and simple approach to decrease the effects of smoking in pregnancy on newborn pulmonary function and respiratory morbidities. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00632476.

Is vitamin D deficiency correlated with childhood wheezing and asthma?

There is increasing evidence that vitamin D regulates immune responses. There is also epidemiological evidence of a relationship between vitamin D deficiency and development of asthma. In addition, several epidemiological studies suggest that low levels of vitamin D during pregnancy and early life are inversely associated with the risk of developing respiratory infections and wheezing in childhood. Vitamin D also seems to reduce asthma exacerbation and increase the response to glucocorticoids. These findings have led to considering a possible link between the occurrence of allergic respiratory diseases and low levels of vitamin D. However, the precise role of vitamin D in the pathogenesis of asthma still remains unclear, emphasizing the need for well-designed trials on vitamin D supplementation to decipher its role in preventing and/or managing the disease. This review examines the relationship that exists between vitamin D deficiency and childhood wheezing and asthma.

Serum heavy metal and antioxidant element levels of children with recurrent wheezing

Study Objectives: The aim of the study is to investigate the levels of toxic heavy metals related with environmental pollution and trace elements involved in antioxidant system in children suffering from recurrent wheezing. Study Design: One hundred children with recurrent wheezing (at least three recurrences) between the ages from 1 to 6 years took part in the study, and also 116 age- and sex- matched healthy children were involved in the study as a control group. Venous blood samples were collected and serum mercury, lead, aluminium, zinc, selenium, and copper levels were studied using ICP-MS. Results: Serum lead (0.76±0.15 vs. 0.27±0.01, p:0.001) and mercury levels (1.31±0.15 vs 0.71±0.05, p < 0.001) were higher in wheezy group than those acquired from the control group. Serum zinc (69.4±1.65 vs. 78.9±2.78, p:0.005) and selenium (115.6±1.87 vs. 125.4±2.94, p:0.008) levels were lower in wheezy group than those acquired from the control group. Serumz inc levels were found to be correlated with number of ARTIs (rp: -0.332, p: 0.001) and the number of wheezy attacks (rp: -0.776, p < 0.001) during the previous year in the wheezy group. Conclusion: Elevated levels of serum lead and mercury and low levels of zinc and selenium may suggest some disturbances in the antioxidant system in children with recurrent wheezing. This means that children with recurrent wheezing are much more susceptible to environmental pollutants and respiratory tract infections than healthy children and this heavy metal-antioxidant relationship may play a role as a contributing factor in the pathogenesis of recurrent wheezingin children (AU)

Sputum zinc concentration and clinical outcome in older asthmatics.

BACKGROUND AND OBJECTIVE: Mouse models of asthma show that zinc deficiency is associated with airway inflammation (AI), which is attenuated by zinc supplements. Whether zinc has a similar role in the human airway remains controversial, with studies demonstrating both high and low plasma zinc concentrations [Zn] in asthmatic patients compared with control subjects. This variability may reflect the inability of plasma measurements to accurately assess airway zinc levels. Examination of induced sputum is an established technique for measuring AI and mediators of inflammation. Recent advances allow measurement of the rapidly exchangeable (labile) and total zinc pools in sputum. The aims of this study were to measure labile and total [Zn] in sputum and plasma of subjects with or without asthma, and second to correlate [Zn] with symptoms, asthma severity, lung function (FEV(1)) and airway hyper-responsiveness. METHODS: A total of 163 subjects (114 with asthma) completed a single visit for sputum induction and a blood test. Labile and total [Zn] were measured by Zinquin fluorescence and atomic absorption spectrophotometry. RESULTS: The mean (SD) age of subjects with and without asthma was 55 (14) and 57 (14) years, respectively. Baseline FEV(1) was significantly lower in subjects with asthma (94.2 (16)%) than in those without asthma (103 (16.6)%). Sputum total and labile [Zn] were lower in subjects with asthma compared with control subjects, with median (interquartile range) values of 31.8 (117) versus 50 (188.5), P = 0.02 and 0 (48) versus 26 (84.5) µg/L, P = 0.05, respectively. Increased frequency of wheeze, as well as asthma severity and reduced FEV(1), was associated with significantly lower labile sputum [Zn]. CONCLUSIONS: These findings suggest that sputum [Zn] reflect clinical outcomes and underlying AI, suggesting a potential role for zinc as a biomarker in asthma.

Neumonías de repetición y fisioterapia respiratoria: a propósito de un caso clínico / Recurrent pneumonia and respiratory physiotherapy: a case report

Objetivos: valorar el efecto de las técnicas de fisioterapia respiratoria en un paciente de 4 años de edad que sufre neumonías de repetición en diferentes localizaciones, lóbulo inferior izquierdo, lóbulo medio derecho y lóbulo inferior derecho.Paciente y métodos: el paciente es derivado por neumología para recibir tratamiento de fisioterapia respiratoria en clínica privada. El tratamiento se llevó a cabo durante 3 semanas en las que se realizaron técnicas de expansión pulmonar y desobstrucción bronquial.Resultados: en la auscultación disminuye el número de sibilancias, aumenta la ventilación y desaparecen los crujidos; los principales valores espirométricos aumentan (FEF 25-75% del 23 al 89%; FEV1/FVC del 86,38 al 96%), disminuye el uso de fármacos y desaparecen las condensaciones pulmonares en radiología.Conclusiones: el programa de fisioterapia respiratoria expuesto resuelve el caso clínico presentado(AU)

Aims: To evaluate the effect of the respiratory physiotherapy techniques in a 4-year old patient who suffered recurrent pneumonia in different sites, these being the lower left lobe, middle right lobe and lower right lobe.Patient and methodsThe patient was referred by the pneumology department for respiratory physiotherapy treatment in a private clinic. Treatment was given for 3 weeks, performing pulmonary expansion and disobstruction maneuver techniques.Results: The auscultation showed a decrease in number of whistling rales, increase in ventilation and disappearance of crepitations. The main spirometric values increased from FEF 25%-75%: 23% to 89%, FEV1/FVC: 86, 38% to 96%. Uses of drugs decreased and the pulmonary condensations disappeared.Conclusions: The respiratory physiotherapy program presented solved the clinical presented case(AU)

Early childhood wheezing symptoms in relation to plasma selenium in pregnant mothers and neonates.

OBJECTIVE: Reduced dietary selenium intake has been linked to the development of asthma. We have investigated whether childhood wheezing symptoms, and asthma up to the age of 5 years are associated with plasma selenium and erythrocyte glutathione peroxidase (GPx) concentrations in pregnant mothers and neonates. METHODS: Two thousand pregnant women were recruited and their 1924 singleton children followed up. Plasma selenium and erythrocyte GPx concentrations were measured in maternal blood during early pregnancy (12 weeks gestation) and in neonatal cord blood. Cohort children were followed up at 1, 2 and 5 years using a respiratory symptom questionnaire and at 5 years children were also invited for spirometry and skin-prick test (SPT). Maternal and neonatal plasma selenium and erythrocyte GPx were related to the childhood outcomes of wheezing, and asthma. RESULTS: At 2 years 1282 children were followed up. At 5 years symptom data were available for 1167 children, 700 children were SPT tested, and forced expiratory volume in 1 s (FEV(1)) was measured in 478. Maternal plasma selenium concentration during early pregnancy was inversely associated with wheezing (odds ratio per 10 microg/kg plasma selenium 0.86, 95% confidence interval 0.76-0.97), and consulting a doctor because of wheeze (0.79, 0.69-0.93) in the second year of life. Cord plasma selenium was also inversely associated with wheezing (0.67, 0.47-0.96), and consulting a doctor because of wheeze (0.62, 0.41-0.93) in the second year of life. By age 5 these associations had disappeared. Maternal and neonatal erythrocyte GPx concentrations were not associated with any childhood outcomes at 2 or 5 years. CONCLUSION: The selenium status of mothers during early pregnancy, and neonates is associated with early childhood wheezing but not asthma or atopic sensitization, furthermore, this association is absent by the age of 5 years.

Maternal intake of vitamin D during pregnancy and risk of recurrent wheeze in children at 3 y of age.

BACKGROUND: Vitamin D deficiency and asthma are common at higher latitudes. Although vitamin D has important immunologic effects, its relation with asthma is unknown. OBJECTIVE: We hypothesized that a higher maternal intake of vitamin D during pregnancy is associated with a lower risk of recurrent wheeze in children at 3 y of age. DESIGN: The participants were 1194 mother-child pairs in Project Viva-a prospective prebirth cohort study in Massachusetts. We assessed the maternal intake of vitamin D during pregnancy from a validated food-frequency questionnaire. The primary outcome was recurrent wheeze, ie, a positive asthma predictive index (>or=2 wheezing attacks among children with a personal diagnosis of eczema or a parental history of asthma). RESULTS: The mean (+/-SD) total vitamin D intake during pregnancy was 548 +/- 167 IU/d. By age 3 y, 186 children (16%) had recurrent wheeze. Compared with mothers in the lowest quartile of daily intake (median: 356 IU), those in the highest quartile (724 IU) had a lower risk of having a child with recurrent wheeze [odds ratio (OR): 0.39; 95% CI: 0.25, 0.62; P for trend < 0.001]. A 100-IU increase in vitamin D intake was associated with lower risk (OR: 0.81; 95% CI: 0.74, 0.89), regardless of whether vitamin D was from the diet (OR: 0.81; 95% CI: 0.69, 0.96) or supplements (OR: 0.82; 95% CI: 0.73, 0.92). Adjustment for 12 potential confounders, including maternal intake of other dietary factors, did not change the results. CONCLUSION: In the northeastern United States, a higher maternal intake of vitamin D during pregnancy may decrease the risk of recurrent wheeze in early childhood.

Disproportionate breathlessness associated with deep sighing breathing in a patient presenting with difficult-to-treat asthma.

Disproportionate breathlessness is a term that is used synonymously with dysfunctional breathing and idiopathic hyperventilation in the absence of chest disease. In the presence of chest disease, it may not be possible to use these three terms interchangeably. We report a case of a patient with documented asthma but breathlessness that was out of proportion to the measured lung function or exercise tolerance. The breathing pattern was abnormal and was characterized by the need to take frequent deep sighs, which increased in frequency during incremental exercise, despite increasing respiratory rate and tidal volume. Treatment with physiotherapist-led breathing retraining resulted in an improvement in the sigh rate and breathlessness scores. Disproportionate breathlessness and deep sighing breathing are part of the spectrum of conditions that comprise dysfunctional breathing and can cause symptoms that may be wrongly attributed to asthma.

Total airway obstruction during local anesthesia in a non-sedated patient with a compromised airway.

PURPOSE: To report a case of complete upper airway obstruction after topicalization with lidocaine in a completely conscious patient with partial upper airway obstruction. CLINICAL FEATURES: A 69-yr-old man with a history of neck cancer and radiation presented for resection of recurrent neck tumour. No preoperative sedation was given. He had inspiratory and expiratory stridor but had no history of aspiration or swallowing problem. Phonation was distorted but effective. The surgeon was reluctant to perform an awake tracheostomy under local anesthesia. In preparation for a fibrescope-assisted orotracheal intubation, the non-sedated patient was given topical upper airway lidocaine during which he developed total airway obstruction and hypoxemia. He was immediately intubated with a fibrescope. His vocal cords were not edematous although the supraglottic structures appeared to be. The vocal cords were abducted and their movement was limited and not paradoxical. Tumour resection was uneventful upon successful tracheal intubation and general anesthesia. Tracheostomy at the end of the case was difficult, as expected. The patient tolerated the procedures and regained consciousness with no neurologic sequelae. CONCLUSION: Dynamic airflow limitation associated with local anesthesia of the upper airway may lead to complete upper airway obstruction in a compromised airway. The main cause may be the loss of upper airway muscle tone, exacerbated by deep inspiration during panic.

Respiratory disorders and allergies in tea packers.

The aim of this study was to determine whether respiratory symptoms or cross-shift declines in lung function were related to occupational exposure to tea dust. A cross-sectional epidemiological study was conducted at a tea-packing plant. Subjects completed a questionnaire, spirometry before and after a full work shift, skin prick testing and venipuncture. Among the 83% of the workers at the site who participated, the prevalences of asthma, wheezing, hay fever and atopy were similar to the general population. Work-related nasal symptoms were more commonly reported by blenders and operators. There were six (3.2%) subjects with a cross-shift decline in the forced expiratory volume in 1 s of > 10%. Specific immunoglobulin E antibodies to black or chamomile tea were observed in 10 (5.6%) employees. As there was little evidence of specific allergic sensitization to the tea varieties tested, the excess of work-related respiratory and nasal symptoms probably represented non-specific irritation.

Development of seasonal allergic rhinitis during the first 7 years of life.

BACKGROUND: Against the background of the controversial discussion about an increase in allergic rhinitis in recent years, intraindividual longitudinal data is lacking for IgE-mediated seasonal allergic rhinitis (SAR). Little is known about the development of SAR in terms of prevalence and incidence rates from birth to school age. OBJECTIVE: In a prospective birth cohort, we investigated the development of sensitization and symptoms of SAR. SAR should be defined with high specificity, and associated risk factors should be determined. METHODS: Annual longitudinal data about seasonal allergic symptoms and sensitization was available for 587 children from birth to their seventh birthday. The definition of SAR was based on a combination of exposure-related symptoms and sensitization. RESULTS: Up to 7 years of age, SAR developed in 15% of the children. Incidence and prevalence of symptoms and sensitization were low during early childhood (<2%) and increased steadily with age. Children in which SAR had already developed in the second year all were born in spring or early summer, resulting in at least two seasons of pollen exposure before manifestation of SAR. Risk factors assessed by multiple logistic regression analysis were male sex (odds ratio [OR] = 2.4), atopic mothers (OR = 2.6) and fathers (OR = 3.6) having allergic rhinitis themselves, first-born child (OR = 2.0), early sensitization to food (OR = 3.3), and atopic dermatitis (OR = 2.5), whereas early wheezing was not associated with SAR. CONCLUSION: The development of SAR is characterized by a marked increase in prevalence and incidence after the second year of life. Our longitudinal data further indicate that in combination with the risk of allergic predisposition, at least 2 seasons of pollen allergen exposure are needed before allergic rhinitis becomes clinically manifest.