Asthma, atopy and exhaled nitric oxide in a cohort of 6-yr-old New Zealand children.

BACKGROUND: Exhaled nitric oxide has been promoted as a non-invasive measure of airway inflammation, with clinical utility for the diagnosis and management of asthma. AIM: We studied associations between exhaled nitric oxide, asthma and atopy in a variety of clinically relevant phenotypes in a cohort of 6-yr-old children. METHOD: Asthma was defined using standard questionnaire criteria, atopy was measured using skin prick tests (SPT) and specific IgE to common allergens, and exhaled nitric oxide was measured using a chemiluminescence analyser according to American and European Thoracic Society criteria. RESULTS: Exhaled nitric oxide was strongly related to atopy and in particular to sensitization to house dust mites. Children with non-allergic asthma had no increase in exhaled nitric oxide compared with non-asthmatic children. Compared with children who never wheezed both late onset and persistent, wheezing was associated with increased FE(NO), while early transient wheezing was not. Elevated levels of exhaled nitric oxide amongst children with allergic asthma were almost entirely explained by their levels of specific IgE to aeroallergens, predominantly D pteronyssinus. CONCLUSION: Airway inflammation as measured by exhaled nitric oxide in young New Zealand children is related to their level of specific IgE to aeroallergens. This has implications for the utility of nitric oxide as a diagnostic and management tool in childhood asthma and for the importance of specific IgE as a marker of asthma severity.

Impact of panic disorder upon self-management educational goals in chronic obstructive pulmonary disease?

The rationale for introducing self-management plans for the whole chronic obstructive pulmonary disease (COPD) population is uncertain. This study's aim was to investigate whether people with panic disorder (PD), compared to non-panic-disordered (NPD), derived additional educational or psychological benefits from having a self-management plan. The 24-week prospective study followed 76 participants hospitalized with an exacerbation of COPD. Participants completed mental health questionnaires including psychological measures of self-management plan impact. Subsequently, a nurse provided education for using a self-management plan. All participants were Plan naïve irrespective of their PD status. Self-management knowledge was assessed before introducing the Plan (baseline), 1 week post discharge and at 24 weeks. At baseline 28 (37%) of participants met the criteria for PD and this group had higher scores (better knowledge) for an impending (p < 0.05) and severe exacerbation (p < 0.05) and capacity to act during a severe exacerbation (p < 0.01). No interaction effect was found between PD and NPD scores over time, indicating that the PD's knowledge did not improve or deteriorate over time relative to the NPD. Evidence was mixed regarding the Plan's psychological impact. Self-management confidence improved in both groups. Amongst the PD group, perceived control of self-management tasks increased but so did body vigilance and distress about having COPD. There is mixed evidence regarding educational and psychological benefits of COPD self-management plans for people with PD. No additional educational advantages were found for the PD group. Plans may increase confidence and control over self-management but may also increase body vigilance and distress about having COPD.

Latex-enhanced immunoassay d-dimer and blood gases can exclude pulmonary embolism in low-risk patients presenting to an acute care setting.

BACKGROUND: Pulmonary embolism (PE) is common, and diagnosis is often difficult. Investigation has traditionally required expensive imaging procedures that are frequently nondiagnostic. Consequently, current practice favors noninvasive diagnosis of PE using algorithms combining risk assessment and d-dimer. Despite the proven safety of this approach, concern persists about such strategies to exclude PE, largely due to variable d-dimer sensitivity. The aim of this study was to prospectively assess the safety of a new algorithm combining a novel, rapid d-dimer test (IL Test; Instrumentation Laboratory; Lexington, MA), Pa(O2) measurement, and risk factor assessment in excluding PE in subjects presenting to an acute care setting. METHODS: All patients aged 18 to 60 years presenting to the emergency department of Christchurch Hospital with suspected PE underwent measurement of d-dimer (IL Test latex-enhanced immunoassay) and Pa(O2), and were assessed for the presence of major clinical risk factors. Those with no risk factors, normal d-dimer findings, and Pa(O2) > or = 80 mm Hg (study arm A) were discharged and followed up by telephone questionnaires over 12 months. Those with elevated d-dimer levels, Pa(O2) < 80 mm Hg, or one or more risk factors (study arm B) were managed as per hospital guidelines. Outcome data were collected on these patients. Our primary outcome was incidence of PE in group A during the first 3-month follow-up period. RESULTS: Three hundred twenty-eight patients were enrolled, of whom 149 were assigned to group A and 179 were assigned to group B. In none of the group A patients was PE diagnosed over the subsequent 3-month period (0%; 95% confidence interval, 0 to 2.1%). PE was diagnosed in 37 group A patients (21%). CONCLUSIONS: The latex-enhanced immunoassay d-dimer and normal arterial oxygen pressure levels can safely exclude PE in a low-risk population presenting to an acute care setting. While these results cannot be extrapolated to all patients with suspected PE, they do confirm the safety of this approach in a population with a low underlying risk of PE.

Maori have a much higher incidence of community-acquired pneumonia and pneumococcal pneumonia than non-Maori: findings from two New Zealand hospitals.

To determine the incidence rates of community-acquired pneumonia and pneumococcal pneumonia requiring hospitalisation among Maori and non-Maori, an observational study was conducted in Christchurch and Hamilton. Self-reported data were collected using an interviewer-administered questionnaire. Routine clinical, radiological, and microbiological techniques were used apart from the BinaxNow pneumococcal antigen test for diagnosis of this infection. Census data was used to determine the denominator for statistical analyses. The pneumonia rate overall was 3.03 times higher among Maori than non-Maori (p<0.001). Differences were significant for each 10-year age group from age 45-74 years (p<0.05). The rate of pneumococcal pneumonia was 3.23 fold higher for Maori than non-Maori (p<0.001), but it did not reach statistical significance in the age-related comparisons. These ethnic disparities are of major concern, and policy planners should consider further interventions to improve the efficacy of current anti-smoking campaigns and to undertake studies of conjugate pneumococcal vaccines for Maori.

Endotoxin exposure, wheezing, and rash in infancy in a New Zealand birth cohort.

BACKGROUND: Wheezing in infancy is common and is associated with small lungs, viral respiratory tract infection, and environmental tobacco smoke exposure. Recently, increased levels of endotoxin in the domestic environment have also been associated with infant wheezing, particularly among infants with a family history of atopic disease. OBJECTIVE: To explore associations between exposure to endotoxin at 3 months of age and reported symptoms of wheezing, rhinitis, itchy scaly rash, and atopy at 15 months in a birth cohort of 881 New Zealand children. METHODS: Using standardized methods, a 1-m(2) site from the bedroom floors of the 3-month-old infants was sampled and analyzed for endotoxin. RESULTS: Wheezing was significantly associated with higher endotoxin levels (odds ratio [OR], 1.54; 95% CI, 1.03-2.30), particularly among infants with a parental history of allergic disease (OR, 1.67; 95% CI, 1.07-2.60). Higher endotoxin concentrations were also strongly associated with recurrent itchy rashes (OR, 1.87; 95% CI, 1.14-3.05), particularly among infants who were atopic (OR, 4.64; 95% CI, 1.56-13.77) or had a parental history of allergic disease (OR, 2.10; 95% CI, 1.22-3.61). CONCLUSION: Domestic endotoxin was associated with reported airway and skin symptoms in this large group of New Zealand infants. The role of endotoxin in the development of respiratory and skin disease in infancy deserves further study. CLINICAL IMPLICATIONS: Reducing domestic endotoxin exposure might reduce infant wheezing and atopic dermatitis, but the long-term benefits of this remain unclear.

The use of inhaled and related respiratory medications in Christchurch rest homes.

AIM: To describe the use of inhaled and related respiratory medications ('asthma medications') and associated management amongst Christchurch rest-home residents. METHODS: Fifty per cent of Christchurch rest homes were randomly selected. All residents on asthma medications, the rest-home managers, care-giving staff, and the residents' general practitioners were interviewed using specific questionnaires. RESULTS: All of the rest homes, residents using asthma medications and senior staff members participated. Seventy five per cent of caregivers and 73% of general practitioners took part. Asthma medications were used by 13% of 1416 rest-home residents. Eighty four per cent of these used a preventer medication, mostly inhaled steroids. Some daily doses exceeded current treatment guidelines. One third of residents using inhalers had an inadequate technique. Some staff and residents chose the wrong inhaler to manage 'shortness of breath'. Regular bronchodilator dosing, rather than 'as required', was common. Those using a spacer device usually had a good technique. Residents appreciated non-pharmacological strategies for breathlessness. Staff identified a need for clear written management plans. CONCLUSIONS: There were significant deficiencies in the staff and residents' knowledge of obstructive airways management and medications. Regular review of inhaler technique, greater use of spacers, and regular staff education may improve residents' respiratory management. Inhaled corticosteroids may be used in too high a dose. Inconsistent management of acutely deteriorating asthma/chronic obstructive pulmonary disease may be addressed by greater use of written management plans in residents' notes.

Bifidobacterial species differentially affect expression of cell surface markers and cytokines of dendritic cells harvested from cord blood.

The gut microbiota may be important in the postnatal development of the immune system and hence may influence the prevalence of atopic diseases. Bifidobacteria are the most numerous bacteria in the guts of infants, and the presence or absence of certain species could be important in determining the geographic incidence of atopic diseases. We compared the fecal populations of bifidobacteria from children aged 25 to 35 days in Ghana (which has a low prevalence of atopy), New Zealand, and the United Kingdom (high-prevalence countries). Natal origin influenced the detection of bifidobacterial species in that fecal samples from Ghana almost all contained Bifidobacterium infantis whereas those of the other children did not. Choosing species on the basis of our bacteriological results, we tested bifidobacterial preparations for their effects on cell surface markers and cytokine production by dendritic cells harvested from cord blood. Species-specific effects on the expression of the dendritic-cell activation marker CD83 and the production of interleukin-10 (IL-10) were observed. Whereas CD83 expression was increased and IL-10 production was induced by Bifidobacterium bifidum, Bifidobacterium longum, and Bifidobacterium pseudocatenulatum, B. infantis failed to produce these effects. We concluded that B. infantis does not trigger the activation of dendritic cells to the degree necessary to initiate an immune response but that B. bifidum, B. longum, and B. pseudocatenulatum induce a Th2-driven immune response. A hypothesis is presented to link our observations to the prevalence of atopic diseases in different countries.