Impact of COVID-19 and lockdown on COPD admissions to Christchurch Hospital, New Zealand 2020-2021: a combined quantitative and qualitative study.

BACKGROUND: During the year following New Zealand's first COVID-19 lockdown, a 33% reduction in chronic obstructive pulmonary disease (COPD)-related admissions occurred and persisted beyond this period at Christchurch Hospital. AIM: To identify contributing factors which may have resulted in a persistent decrease in COPD hospitalisation rates at Christchurch Hospital following the 2020 COVID-19 lockdown. METHODS: Using an explanatory sequential mixed-methods research design, we (i) retrospectively analysed hospital admissions and primary healthcare access by people with COPD (n = 1358) in Canterbury before, during and after COVID lockdown (24 March 2019 to 2021) and (ii) undertook individual interviews from a sample of patients (n = 14). RESULTS: Patients who were not re-admitted following the COVID-19 lockdown had fewer general practice encounters, acute primary care access, antibiotic and prednisone prescriptions. Proportionally fewer Maori and more Pacific patients were admitted with COPD following lockdown. Positive contributing factors at a primary care level included improvements in primary care interactions and medication management. At a patient and community level, there were improvements in lifestyle, self-management practices, social support and contact precautions. However, a subgroup of patients described negative effects such as social isolation. CONCLUSION: A combination of patient, primary care and community-level factors led to an overall persistent decrease in COPD admissions following the COVID-19 lockdown. Future targeted and individualised measures focusing on these modifiable factors may decrease future COPD-related hospital admissions. The study design facilitated further explanation about factors that contributed to the persistent decrease in hospital admissions among people living with COPD and has underscored the importance of social support, patient empowerment and reduction in barriers in accessing care in admission reduction.

DNA methylation patterns at birth predict health outcomes in young adults born very low birthweight.

BACKGROUND: Individuals born very low birthweight (VLBW) are at increased risk of impaired cardiovascular and respiratory function in adulthood. To identify markers to predict future risk for VLBW individuals, we analyzed DNA methylation at birth and at 28 years in the New Zealand (NZ) VLBW cohort (all infants born < 1500 g in NZ in 1986) compared with age-matched, normal birthweight controls. Associations between neonatal methylation and cardiac structure and function (echocardiography), vascular function and respiratory outcomes at age 28 years were documented. RESULTS: Genomic DNA from archived newborn heel-prick blood (n = 109 VLBW, 51 controls) and from peripheral blood at ~ 28 years (n = 215 VLBW, 96 controls) was analyzed on Illumina Infinium MethylationEPIC 850 K arrays. Following quality assurance and normalization, methylation levels were compared between VLBW cases and controls at both ages by linear regression, with genome-wide significance set to p < 0.05 adjusted for false discovery rate (FDR, Benjamini-Hochberg). In neonates, methylation at over 16,400 CpG methylation sites differed between VLBW cases and controls and the canonical pathway most enriched for these CpGs was Cardiac Hypertrophy Signaling (p = 3.44E-11). The top 20 CpGs that differed most between VLBW cases and controls featured clusters in ARID3A, SPATA33, and PLCH1 and these 3 genes, along with MCF2L, TRBJ2-1 and SRC, led the list of 15,000 differentially methylated regions (DMRs) reaching FDR-adj significance. Fifteen of the 20 top CpGs in the neonate EWAS showed associations between methylation at birth and adult cardiovascular traits (particularly LnRHI). In 28-year-old adults, twelve CpGs differed between VLBW cases and controls at FDR-adjusted significance, including hypermethylation in EBF4 (four CpGs), CFI and UNC119B and hypomethylation at three CpGs in HIF3A and one in KCNQ1. DNA methylation GrimAge scores at 28 years were significantly greater in VLBW cases versus controls and weakly associated with cardiovascular traits. Four CpGs were identified where methylation differed between VLBW cases and controls in both neonates and adults, three reversing directions with age (two CpGs in EBF4, one in SNAI1 were hypomethylated in neonates, hypermethylated in adults). Of these, cg16426670 in EBF4 at birth showed associations with several cardiovascular traits in adults. CONCLUSIONS: These findings suggest that methylation patterns in VLBW neonates may be informative about future adult cardiovascular and respiratory outcomes and have value in guiding early preventative care to improve adult health.

Symptom persistence and recovery among COVID-19 survivors during a limited outbreak in Canterbury, New Zealand: a prospective cohort study.

BACKGROUND: In Canterbury, near complete identification of coronavirus disease 2019 (COVID-19) cases during a limited outbreak provides unique insights into sequelae. AIMS: The current study aimed to measure symptom persistence, time to return to normal activity, generalised anxiety and health-related quality of life (HrQoL) among COVID-19 survivors compared with uninfected participants. METHODS: The authors conducted a prospective cohort study of people tested for COVID-19 by reverse transcriptase polymerase chain reaction of nasopharyngeal swabs from 1 March to 30 June 2020. They enrolled participants who tested positive and negative at a 1:2 ratio, and administered community-acquired pneumonia, 7-item generalised anxiety disorder (GAD-7) and HrQoL (RAND-36) questionnaires. RESULTS: The authors recruited 145 participants, 48 with COVID-19 and 97 without COVID-19. The mean time from COVID-19 testing to completing the health questionnaire was 306 days. The mean age of patients was 46.7 years, and 70% were women. Four (8%) COVID-19-positive and eight (8%) COVID-19-negative participants required hospitalisation. Fatigue (30/48 [63%] vs 13/97 [13%]; P < 0.001), dyspnoea (13/48 [27%] vs 6/97 [6%]; P < 0.001) and chest pain (10/48 [21%] vs 1/97 [1%]; P < 0.001) were persistent in those with COVID-19. Fewer COVID-19-positive participants returned to normal activity levels (35/48 [73%] vs 94/97 97%; P < 0.001), with longer times taken (median 21 vs 14 days; P = 0.007). The GAD-7 and RAND-36 scores of both groups were similar across all anxiety and HrQoL subscales. CONCLUSIONS: Persistent symptoms and longer recovery times were found in COVID-19 survivors, but not impaired generalised anxiety levels or HrQoL compared with COVID-19-uninfected participants.

Reduced Exercise Capacity in Adults Born at Very Low Birth Weight: A Population-based Cohort Study.

Rationale: Population-based data regarding the consequences of very low birth weight (VLBW) and bronchopulmonary dysplasia (BPD) on adult exercise capacity are limited. Objectives: To compare exercise capacity in a national VLBW cohort with term-born controls and explore factors contributing to the differences. Methods: At 26-30 years of age, 228 VLBW survivors and 100 controls underwent lung function tests, cardiopulmonary exercise testing, and assessment of resting cardiac structure and function using echocardiography. Data on self-reported physical activity were collected. Measurements and Main Results: Compared with controls, adults with VLBW demonstrated reduced oxygen uptake, work rate, and oxygen pulse at peak exercise (9.3%, 10.7%, and 10.8% lower, respectively) and earlier anaerobic threshold (all P < 0.0001), with all mean values within normal range. VLBW survivors showed reduced physical activity, impaired lung function (reduced FEV1, FEV1/FVC, and DlCO), altered left ventricular structure and function (reduced mass, size, stroke volume, and cardiac output), and reduced right atrial and ventricular size. Adjustment for the combination of three sets of covariates (physical activity with body mass index, lung function, and cardiac structure and function) explained most of the exercise group differences. Beyond the effects of physical activity and body mass index, lung function and cardiac structure and function contributed approximately equally. BPD with other prematurity-related perinatal factors (ventilation, antenatal steroids, extremely low birth weight, and extreme preterm) were not associated with a reduced exercise capacity. Conclusions: Exercise capacity was significantly reduced in adults with VLBW, which we speculate is from combined effects of impaired lung function, altered heart structure and function, and reduced physical activity. Perinatal factors including BPD were not associated with a reduced exercise capacity.

Drug metabolism in severe chronic obstructive pulmonary disease: A phenotyping cocktail study.

AIMS: To evaluate the effect of severe chronic obstructive pulmonary disease (COPD) on drug metabolism by comparing the pharmacokinetics of patients with severe COPD with healthy volunteers and using the modified Inje drug cocktail. METHODS: This was a single-centre pharmacokinetic study with 12 healthy participants and 7 participants with GOLD D COPD. Midazolam 1 mg, dextromethorphan 30 mg, losartan 25 mg, omeprazole 20 mg, caffeine 130 mg and paracetamol 1000 mg were simultaneously administered and intensive pharmacokinetic sampling was conducted over 8 hours. Drug metabolism by CYP3A4, CYP2D6, CYP2C9, CYP2C19, CYP1A2, UGT1A6 and UGT1A9 in participants with COPD were compared with phenotypes in healthy controls. RESULTS: The oral clearance (95% confidence interval) in participants with COPD relative to controls was: midazolam 63% (60-67%); dextromethorphan 72% (40-103%); losartan 53% (52-55%); omeprazole 35% (31-39%); caffeine 52% (50-53%); and paracetamol 73% (72-74%). There was a 5-fold increase in AUC for omeprazole and approximately 2-fold increases for caffeine, losartan, dextromethorphan, and midazolam. The AUC of paracetamol, which is mostly glucuronidated, was increased by about 60%. CONCLUSION: Severe COPD is associated with a clinically significant reduction in oral drug clearance. This may be greater for cytochrome P450 substrates than for glucuronidated drugs. This supports reduced starting doses when prescribing for patients with severe COPD.

Lung Function of Adults Born at Very Low Birth Weight.

BACKGROUND: Much remains unknown about the consequences of very low birth weight (VLBW) and bronchopulmonary dysplasia (BPD) on adult lungs. We hypothesized that VLBW adults would have impaired lung function compared with controls, and those with a history of BPD would have worse lung function than those without. METHODS: At age 26 to 30 years, 226 VLBW survivors of the New Zealand VLBW cohort and 100 term controls born in 1986 underwent lung function tests including spirometry, plethysmographic lung volumes, diffusing capacity of the lung for carbon monoxide, and single-breath nitrogen washout (SBN2). RESULTS: An obstructive spirometry pattern was identified in 35% VLBW subjects versus 14% controls, with the majority showing mild obstruction. Compared with controls, VLBW survivors demonstrated significantly lower forced expiratory volume in 1 second (FEV1), FEV1/forced vital capacity (FVC) ratio (FEV1/FVC), forced expiratory flow at 25% to 75% of FVC and higher residual volume (RV), RV/total lung capacity (TLC) ratio (RV/TLC), decreased diffusing capacity of the lung for carbon monoxide, and increased phase III slope for SBN2. The differences persisted after adjustment for sex and smoking status. Within the VLBW group, subjects with BPD showed significant reduction in FEV1, FEV1/FVC, and forced expiratory flow at 25% to 75% of FVC, and increase in RV, RV/TLC, and phase III slope for SBN2, versus subjects without. The differences remained after adjustment for confounders. CONCLUSIONS: Adult VLBW survivors showed a higher incidence of airflow obstruction, gas trapping, reduced gas exchange, and increased ventilatory inhomogeneity versus controls. The findings suggest pulmonary effects due to VLBW persist into adulthood, and BPD is a further insult on small airway function.

Oxidative cross-linking of calprotectin occurs in vivo, altering its structure and susceptibility to proteolysis.

Calprotectin, the major neutrophil protein, is a critical alarmin that modulates inflammation and plays a role in host immunity by strongly binding trace metals essential for bacterial growth. It has two cysteine residues favourably positioned to act as a redox switch. Whether their oxidation occurs in vivo and affects the function of calprotectin has received little attention. Here we show that in saliva from healthy adults, and in lavage fluid from the lungs of patients with respiratory diseases, a substantial proportion of calprotectin was cross-linked via disulfide bonds between the cysteine residues on its S100A8 and S100A9 subunits. Stimulated human neutrophils released calprotectin and subsequently cross-linked it by myeloperoxidase-dependent production of hypochlorous acid. The myeloperoxidase-derived oxidants hypochlorous acid, taurine chloramine, hypobromous acid, and hypothiocyanous acid, all at 10 µM, cross-linked calprotectin (5 µM) via reversible disulfide bonds. Hypochlorous acid generated A9-A9 and A8-A9 cross links. Hydrogen peroxide (10 µM) did not cross-link the protein. Purified neutrophil calprotectin existed as a non-covalent heterodimer of A8/A9 which was converted to a heterotetramer - (A8/A9)2 - with excess calcium ions. Low level oxidation of calprotectin with hypochlorous acid produced substantial proportions of high order oligomers, whether oxidation occurred before or after addition of calcium ions. At high levels of oxidation the heterodimer could not form tetramers with calcium ions, but prior addition of calcium ions afforded some protection for the heterotetramer. Oxidation and formation of the A8-A9 disulfide cross link enhanced calprotectin's susceptibility to proteolysis by neutrophil proteases. We propose that reversible disulfide cross-linking of calprotectin occurs during inflammation and affects its structure and function. Its increased susceptibility to proteolysis will ultimately result in a loss of function.

Prominent IgE-binding and cytokine-inducing capacities of a newly cloned N-terminal region of Der f 14, an apolipophorin-like house dust mite allergen.

We previously characterized a 177-kDa allergen, M-177, from Dermatophagoides farinae. Thereafter, a counterpart to M-177 for Euroglyphus maynei was cloned as Eur m 14, and its sequence revealed that two environmental allergens, Mag 1 and Mag 3, are digested fragments of M-177. The aims of this study were to clone the cDNA of Der f 14 corresponding to M-177 and to elucidate the allergenic capacities of the N-terminal fragment of Der f 14 (Der f 14-N). Recombinant allergens were produced as trigger-factor-fused proteins in Escherichia coli. Der f 14-N showed the highest IgE-binding frequency among Der f 14-derived fragments in patients allergic to house dust mite by enzyme-linked immunosorbent assay. Der f 14-N showed the highest capacity to induce cell proliferation in murine lymphocyte and human peripheral mononuclear cells among Der f 14-derived fragments. Der f 14-N induced IL-13, IFN-γ and IL-17 production more than Der f 1 and Der f 2 in mouse, and induced IL-5 and IFN-γ production at levels comparable to those of Der f 1 and Der f 2 in some patients. The high prevalence of IgE binding to the Der f 14-N indicates that it could be an important mite allergen.

Hair nicotine at 15 months old, tobacco exposure and wheeze or asthma from 15 months to 6 years old.

OBJECTIVE: To investigate the relationship between hair nicotine levels at 15 months of age and prior parent-reported smoking exposure, and the risk of wheezing and current asthma from 15 months to 6 years of age. STUDY DESIGN: We measured hair nicotine levels at 15 months of age in 376 of 535 infants enrolled in a prospective birth cohort in Christchurch, New Zealand. We obtained detailed information from parents about smoking exposure during pregnancy and in the home at 3 and 15 months of age. Data for demographics, wheezing, and asthma were obtained from yearly questionnaires up to age 6 years. We assessed hair nicotine levels in relation to reported smoke exposure in pregnancy and up to age 15 months, and the association between high levels of hair nicotine and annual reports of current wheeze and current asthma using multiple logistic regression. RESULTS: Hair nicotine increased with numbers of smokers and daily cigarettes smoked at home, and was also strongly associated with smoking in pregnancy. High level of hair nicotine was associated with increased risk of wheeze (Odds ratio 2.30, P = 0.001) and, though not significant, of current asthma (Odds ratio 2.02, P = 0.056) at 15 months of age, after controlling for socio-economic status, ethnicity, body mass index, respiratory infections in the first 3 months of life, and duration of exclusive breastfeeding. At older ages the associations were non-significant. CONCLUSION: In children aged 15 months hair nicotine level was related to smoking exposure, and was associated with increased risk of wheeze and asthma.

Development and outcomes of a primary care-based sleep assessment service in Canterbury, New Zealand.

Prior to 2007, increasing demand for sleep services, plus inability to adequately triage severity, led to long delays in sleep assessment and accessing continuous positive airway pressure. We established a community sleep assessment service carried out by trained general practices using a standardised tool and overnight oximetry. All cases were discussed at a multi-disciplinary meeting, with four outcomes: severe obstructive sleep apnoea treated with continuous positive airway pressure; investigation with more complex studies; sleep physician appointment; no or non-severe sleep disorder for general practitioner management. Assessment numbers increased steadily (~400 in 2007 vs. 1400 in 2015). Median time from referral to assessment and multi-disciplinary meeting was 28 and 48 days, respectively. After the first multi-disciplinary meeting, 23% of cases were assessed as having severe obstructive sleep apnoea. More complex studies (mostly flow based) were required in 49% of patients, identifying severe obstructive sleep apnoea in a further 13%. Thirty-seven percent of patients had obstructive sleep apnoea severe enough to qualify for funded treatment. Forty-eight percent of patients received a definitive answer from the first multi-disciplinary meeting. Median time from referral to continuous positive airway pressure for 'at risk' patients with severe obstructive sleep apnoea, e.g., commercial drivers, was 49 days, while patients with severe obstructive sleep apnoea but not 'at risk' waited 261 days for continuous positive airway pressure. Ten percent of patients required polysomnography, and 4% saw a sleep specialist. In conclusion, establishment of a community sleep assessment service and sleep multi-disciplinary meeting led to significantly more assessments, with short waiting times for treatment, especially in high-risk patients with severe obstructive sleep apnoea. Most patients can be assessed without more complex studies or face-to-face review by a sleep specialist. SLEEP DISORDERS: MORE ASSESSMENTS, SHORTER WAITS WITH COMMUNITY SLEEP SERVICE: A community-based service for common sleep disorders can provide rapid and easily accessed sleep assessment and treatment. A team led by Michael Hlavac and Michael Epton from Christchurch Hospital describe the creation of a sleep assessment service within the Canterbury district of New Zealand, in which initial assessments are conducted throughout the community by general practice teams under guidance and advice from sleep specialists at the region's largest hospital. Before the service, there were around 300 sleep assessments per year in all of Canterbury, a region with a population of around 510,000. Now, that number has more than tripled, with shorter waiting times for treatment, especially for people with severe sleep apnoea. The authors conclude that most patients can be assessed for a suspected sleep disorder without needing to visit a hospital's sleep unit.

Do self-management interventions in COPD patients work and which patients benefit most? An individual patient data meta-analysis.

BACKGROUND: Self-management interventions are considered effective in patients with COPD, but trials have shown inconsistent results and it is unknown which patients benefit most. This study aimed to summarize the evidence on effectiveness of self-management interventions and identify subgroups of COPD patients who benefit most. METHODS: Randomized trials of self-management interventions between 1985 and 2013 were identified through a systematic literature search. Individual patient data of selected studies were requested from principal investigators and analyzed in an individual patient data meta-analysis using generalized mixed effects models. RESULTS: Fourteen trials representing 3,282 patients were included. Self-management interventions improved health-related quality of life at 12 months (standardized mean difference 0.08, 95% confidence interval [CI] 0.00-0.16) and time to first respiratory-related hospitalization (hazard ratio 0.79, 95% CI 0.66-0.94) and all-cause hospitalization (hazard ratio 0.80, 95% CI 0.69-0.90), but had no effect on mortality. Prespecified subgroup analyses showed that interventions were more effective in males (6-month COPD-related hospitalization: interaction P=0.006), patients with severe lung function (6-month all-cause hospitalization: interaction P=0.016), moderate self-efficacy (12-month COPD-related hospitalization: interaction P=0.036), and high body mass index (6-month COPD-related hospitalization: interaction P=0.028 and 6-month mortality: interaction P=0.026). In none of these subgroups, a consistent effect was shown on all relevant outcomes. CONCLUSION: Self-management interventions exert positive effects in patients with COPD on respiratory-related and all-cause hospitalizations and modest effects on 12-month health-related quality of life, supporting the implementation of self-management strategies in clinical practice. Benefits seem similar across the subgroups studied and limiting self-management interventions to specific patient subgroups cannot be recommended.

The New Zealand 1986 very low birth weight cohort as young adults: mapping the road ahead.

BACKGROUND: Very low birth weight (less than 1500 g) is associated with increased morbidity and costs of health care in childhood. Emerging evidence suggests these infants face a range of health and social problems as young adults. We studied all New Zealand very low birth weight infants born in 1986 (when 58% were exposed to antenatal corticosteroids) in infancy, with later follow-up at 7 to 8 years and 23 to 24 years. We now aim to assess the cohort at 26-28 years compared with controls. METHODS/DESIGN: The case sample will comprise a minimum of 250 members of the 1986 New Zealand national very low birth weight cohort (77% of survivors). Outcomes will be compared with a control group of 100 young adults born at term in 1986. Following written informed consent, participants will travel to Christchurch for 2 days of assessments undertaken by experienced staff. Medical assessments include growth measures, vision, respiratory function, blood pressure and echocardiogram, renal function, dental examination and blood tests. Cognitive and neuropsychological functioning will be assessed with standard tests, and mental health and social functioning by participant interview. A telephone interview will be conducted with a parent or significant other person nominated by the respondent to gain a further perspective on the young person's health and functioning. All those born at less than 28 weeks' gestation, plus a random subset of the cohort to a total of 150 cases and 50 controls, will be offered cranial magnetic-resonance imaging. Statistical analysis will examine comparison with controls and long-term trajectories for the very low birth weight cohort. DISCUSSION: The research will provide crucial New Zealand data on the young adult outcomes for very low birth weight infants and address gaps in the international literature, particularly regarding cardiovascular, respiratory, visual and neurocognitive outcomes. These data will inform future neonatal care, provide evidence-based guidelines for care of preterm graduates transitioning to adult care, and help shape health education and social policies for this high risk group. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12612000995875 . Registered 1 October 2012.

The development of a community-based spirometry service in the Canterbury region of New Zealand: observations on new service delivery.

In 2008, as part of the changes to develop integrated health care services in the Canterbury region of New Zealand, the local health board in collaboration with general practitioners, respiratory specialists and scientists introduced a programme for general practices to provide laboratory-quality spirometry in the community. The service adhered to the 2005 ATS/ERS international spirometry standards. The spirometry service was provided by trained practice nurses and community respiratory nurses, and was monitored and quality assured by certified respiratory scientists in the Respiratory Physiology Laboratory, Christchurch Hospital and CISO (Canterbury Initiative Services Organisation). These two organisations were responsible for organising training seminars and refresher courses on spirometry technique and interpretation of results. A total of 10 practices have now become approved spirometry providers, with the number of tests carried out in the primary care setting increasing gradually. Consistently high-quality spirometry tests have been obtained and are now presented on a centrally available results database for all hospital and community clinicians to review. Although the service has proved to be more convenient for patients, the tests have not been delivered as quickly as those carried out by the Respiratory Physiology Laboratory. However, the time scales for testing achieved by the community service is considered suitable for investigation of chronic disease. The success of the service has been dependent on several key factors including hospital and clinical support and a centralised quality assurance programme, a comprehensive training schedule and online clinical guidance and close integration between primary and secondary care clinicians.

Breastfeeding protects against current asthma up to 6 years of age.

OBJECTIVE: To investigate the effects of breastfeeding on wheezing and current asthma in children 2 to 6 years of age. STUDY DESIGN: Infants (n=1105) were enrolled in a prospective birth cohort in New Zealand. Detailed information about infant feeding was collected using questionnaires administered at birth and at 3, 6, and 15 months. From this, durations of exclusive and any breastfeeding were calculated. Information about wheezing and current asthma was collected at 2, 3, 4, 5, and 6 years. Logistic regression was used to model associations between breastfeeding and outcomes with and without adjustment for confounders. RESULTS: After adjustment for confounders, each month of exclusive breastfeeding was associated with significant reductions in current asthma from 2 to 6 years (all, P<.03). Current asthma at 2, 3, and 4 years was also reduced by each month of any breastfeeding (all, P<.005). In atopic children, exclusive breastfeeding for ≥ 3 months reduced current asthma at ages 4, 5, and 6 by 62%, 55%, and 59%, respectively. CONCLUSION: Breastfeeding, particularly exclusive breastfeeding, protects against current asthma up to 6 years. Although exclusive breastfeeding reduced risk of current asthma in all children to age 6, the degree of protection beyond 3 years was more pronounced in atopic children.

Coeliac disease and gluten avoidance in New Zealand children.

OBJECTIVES: Although gluten avoidance is thought to be common among New Zealanders, the prevalence of gluten avoidance and of actual coeliac disease (CD) in children is uncertain. Our aims were: (1) to determine the prevalence of doctor-diagnosed CD and of gluten avoidance in New Zealand children; and (2) among children without CD, to identify independent predictors of gluten avoidance. DESIGN: The New Zealand Asthma and Allergy Cohort Study has detailed information on participants' demographic, pregnancy-related and neonatal factors. The authors surveyed parents regarding their child's history of lactose intolerance and gluten-related issues (eg, gluten avoidance, history of wheat or gluten allergy in first degree relatives, testing and doctor diagnosis of CD). After excluding children with doctor-diagnosed CD, the authors identified independent predictors of gluten avoidance. RESULTS: Among 916 children, most (78%) were of European ethnicity. The authors identified nine (1.0%, 95% CI 0.5% to 1.9%) who had doctor-diagnosed CD, while 48 (5.2%, 95% CI 4.0% to 6.9%) avoided gluten. Among children without diagnosed CD, significant independent predictors for gluten avoidance were Christchurch site (OR 2.2, 95% CI 1.02 to 4.7), prior testing for CD (OR 9.0, 95% CI 4.1 to 19.5) and doctor-diagnosed lactose intolerance (OR 5.2, 95% CI 2.0 to 13.9). CONCLUSIONS: CD affected 1% of these New Zealand children, but 5% reported gluten avoidance. The predictors of gluten avoidance in children without doctor-diagnosed CD suggest important regional differences in community belief or medical practice regarding implementation of gluten avoidance and the contributory role of non-specific subjective abdominal complaints.

Increased concentrations of breath haloamines are not detectable in airways inflammation using SIFT-MS.

The haloamines, including the chloramines (H(2)NCl, HNCl(2)) and bromamine (H(2)NBr), are diffusible gases that are likely to be produced during inflammation and so may be present as markers of lung inflammation on breath. Although haloamines are quite reactive, it is possible to measure these compounds in humid samples using SIFT-MS. Until recently the quantification of haloamines in breath suffered from interference from other common breath compounds. This was overcome by heating the flow tube which removed major water cluster product ions. Despite the improvements to the method, previous attempts to measure the haloamines in breath samples from normal volunteers had found no evidence to support their presence. Since it is proposed that the haloamines may be present in higher concentrations during airways inflammation we have attempted to detect the compounds in the exhaled breath of patients with airways inflammatory conditions. On-line and off-line breath samples were analyzed; however, there was no discernable change to any of product ions when compared to ambient air or normal subjects. This suggests that despite sensitivity in the mid part per trillion range haloamines are not significantly raised in airways inflammation.

Including viral infection data supports an association between particulate pollution and respiratory admissions.

OBJECTIVE: To refine and revise previous air pollution, climate and health time series analysis in Christchurch, New Zealand, introducing viral identification data (positive identification count and outbreak, defined as two of more positive tests). METHOD: The effects on daily respiratory admissions for five years (1998-2002) of air pollution (PM(10) ), climate and virology (incorporating actual counts and outbreaks of influenza A and B (INF), para influenza virus type 3 (PIV) and respiratory syncytial virus (RSV) were examined using generalised additive models (GAMs), which are one of semiparametric models. Results were also compared with a model that included climate and air pollution parameters but without the inclusion of virology data. The data were analysed aggregately and then stratified by age group and season. RESULTS: Different virology data detected various association levels. The highest estimates were a 3.93% (CI: 2.69-5.17) and a 3.88% (CI: 2.65-5.12) rise in respiratory admissions for a rise of 10 µg/m(3) annual PM(10) with outbreak and actual counts of PIV respectively for 0-19 years old with a three-day lag. CONCLUSION: Refining a statistical model with the addition of virology data gives a similar estimation of the association between PM(10) levels and respiratory admissions to previous research. Use of the indicator of an outbreak of viral infection appears to be similar to actual count of viruses detected.

Individual and cumulative effects of GWAS susceptibility loci in lung cancer: associations after sub-phenotyping for COPD.

Epidemiological studies show that approximately 20-30% of chronic smokers develop chronic obstructive pulmonary disease (COPD) while 10-15% develop lung cancer. COPD pre-exists lung cancer in 50-90% of cases and has a heritability of 40-77%, much greater than for lung cancer with heritability of 15-25%. These data suggest that smokers susceptible to COPD may also be susceptible to lung cancer. This study examines the association of several overlapping chromosomal loci, recently implicated by GWA studies in COPD, lung function and lung cancer, in (n = 1400) subjects sub-phenotyped for the presence of COPD and matched for smoking exposure. Using this approach we show; the 15q25 locus confers susceptibility to lung cancer and COPD, the 4q31 and 4q22 loci both confer a reduced risk to both COPD and lung cancer, the 6p21 locus confers susceptibility to lung cancer in smokers with pre-existing COPD, the 5p15 and 1q23 loci both confer susceptibility to lung cancer in those with no pre-existing COPD. We also show the 5q33 locus, previously associated with reduced FEV(1), appears to confer susceptibility to both COPD and lung cancer. The 6p21 locus previously linked to reduced FEV(1) is associated with COPD only. Larger studies will be needed to distinguish whether these COPD-related effects may reflect, in part, associations specific to different lung cancer histology. We demonstrate that when the "risk genotypes" derived from the univariate analysis are incorporated into an algorithm with clinical variables, independently associated with lung cancer in multivariate analysis, modest discrimination is possible on receiver operator curve analysis (AUC = 0.70). We suggest that genetic susceptibility to lung cancer includes genes conferring susceptibility to COPD and that sub-phenotyping with spirometry is critical to identifying genes underlying the development of lung cancer.

Cord-blood 25-hydroxyvitamin D levels and risk of respiratory infection, wheezing, and asthma.

OBJECTIVE: Higher maternal intake of vitamin D during pregnancy is associated with a lower risk of wheezing in offspring. The relationship between cord-blood levels of 25-hydroxyvitamin D (25[OH]D) and childhood wheezing is unknown. We hypothesized that cord-blood levels would be inversely associated with risk of respiratory infection, wheezing, and asthma. PATIENTS AND METHODS: Cord blood from 922 newborns was tested for 25(OH)D. Parents were asked if their child had a history of respiratory infection at 3 months of age or a history of wheezing at 15 months of age and then annually thereafter. Incident asthma was defined as doctor-diagnosed asthma by the time the child was 5 years old and reported inhaler use or wheezing since the age of 4 years. RESULTS: The median cord-blood level of 25(OH)D was 44 nmol/L (interquartile range: 29-78). Follow-up was 89% at the age of 5 years. Adjusting for the season of birth, 25(OH)D had an inverse association with risk of respiratory infection by 3 months of age (odds ratio: 1.00 [reference] for ≥75 nmol/L, 1.39 for 25-74 nmol/L, and 2.16 [95% confidence interval: 1.35-3.46] for <25 nmol/L). Likewise, cord-blood 25(OH)D levels were inversely associated with risk of wheezing by 15 months, 3 years, and 5 years of age (all P < .05). Additional adjustment for more than 12 potential confounders did not materially change these results. In contrast, we found no association between 25(OH)D levels and incident asthma by the age of 5 years. CONCLUSIONS: Cord-blood levels of 25(OH)D had inverse associations with risk of respiratory infection and childhood wheezing but no association with incident asthma.