Jeroen Douwes

Massey University, Palmerston North City, Manawatu-Wanganui, New Zealand

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Publications (199)601.51 Total impact

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    ABSTRACT: Background and objective: Neutrophilic inflammation has been implicated in non-eosinophilic asthma (NEA) in adults, but little is known about NEA in children/adolescents. We assessed clinical and inflammatory characteristics of NEA in adolescent asthma. Methods: Airway inflammation, sputum endotoxin, airway hyper-reactivity, atopy and lung function were assessed in 77 adolescents with asthma and 68 without asthma (12-17 years). Asthma was identified on the basis of wheeze and asthma history. Results: The proportion of NEA (sputum eosinophils <2.5%) was 54%. In this group, atopy, sputum neutrophil, eosinophil, eosinophil cationic protein (ECP), endotoxin, neutrophil elastase and IL-8 levels were not different from those without asthma. In contrast, eosinophilic asthma (EA) was associated with atopy and sputum ECP and IL-8. The majority of NEA had no evidence of inflammation; only 14% had neutrophilia (≥61% neutrophils), compared with 11% of EA, and 15% of those without asthma. Small differences in FEV1 (NS) were found between EA and NEA, but symptom prevalence and severity was not different (63% of EA and 52% of NEA were classified moderate to severe). Conclusion: NEA is common in adolescent asthma and has similar clinical characteristics as EA. Neutrophils do not appear to play a role in NEA in adolescents, and underlying mechanisms may not involve airway inflammation.
    Full-text · Article · Jan 2016 · Respirology
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    ABSTRACT: The prevalence of allergic airway diseases such as asthma and rhinitis has increased dramatically to epidemic proportions worldwide. Besides air pollution from industry derived emissions and motor vehicles, the rising trend can only be explained by gross changes in the environments where we live. The world economy has been transformed over the last 25 years with developing countries being at the core of these changes. Around the planet, in both developed and developing countries, environments are undergoing profound changes. Many of these changes are considered to have negative effects on respiratory health and to enhance the frequency and severity of respiratory diseases such as asthma in the general population. Increased concentrations of greenhouse gases, and especially carbon dioxide (CO2), in the atmosphere have already warmed the planet substantially, causing more severe and prolonged heat waves, variability in temperature, increased air pollution, forest fires, droughts, and floods - all of which can put the respiratory health of the public at risk. These changes in climate and air quality have a measurable impact not only on the morbidity but also the mortality of patients with asthma and other respiratory diseases. The massive increase in emissions of air pollutants due to economic and industrial growth in the last century has made air quality an environmental problem of the first order in a large number of regions of the world. A body of evidence suggests that major changes to our world are occurring and involve the atmosphere and its associated climate. These changes, including global warming induced by human activity, have an impact on the biosphere, biodiversity, and the human environment. Mitigating this huge health impact and reversing the effects of these changes are major challenges. This statement of the World Allergy Organization (WAO) raises the importance of this health hazard and highlights the facts on climate-related health impacts, including: deaths and acute morbidity due to heat waves and extreme meteorological events; increased frequency of acute cardio-respiratory events due to higher concentrations of ground level ozone; changes in the frequency of respiratory diseases due to trans-boundary particle pollution; altered spatial and temporal distribution of allergens (pollens, molds, and mites); and some infectious disease vectors. According to this report, these impacts will not only affect those with current asthma but also increase the incidence and prevalence of allergic respiratory conditions and of asthma. The effects of climate change on respiratory allergy are still not well defined, and more studies addressing this topic are needed. Global warming is expected to affect the start, duration, and intensity of the pollen season on the one hand, and the rate of asthma exacerbations due to air pollution, respiratory infections, and/or cold air inhalation, and other conditions on the other hand.
    Full-text · Article · Dec 2015 · World Allergy Organization Journal
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    ABSTRACT: Reduced asthma and allergy risks in farmers have been ascribed to microbial exposures. However, selection may also play a role and this was assessed in two Scandinavian farming populations. Asthma prevalence in 739 Danish farming students was compared to that of 1,105 siblings. 8,482 Norwegian farmers were also compared with 349 early retired farmers. The prevalence of ever-asthma was 5.4% in farming students and 5.2% in siblings (OR 1.1; 95%CI 0.73-1.7). Current asthma in farmers was 3.0% compared to 6.3% in farmers who had retired early (OR 1.8, 95%CI 1.1-2.9). Adjustments for early retirement increased the asthma prevalence by 0.3-0.6%. Farmers who had changed production were more likely to have asthma (OR 9.8, 95% CI 6.0-16). No healthy worker selection into farming was observed and changes in asthma prevalence due to early retirement were small. Selection effects are therefore unlikely to explain the protective effects of farming on asthma.
    Full-text · Article · Sep 2015 · Annals of agricultural and environmental medicine: AAEM

  • No preview · Article · Aug 2015 · The Journal of allergy and clinical immunology
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    ABSTRACT: BACKGROUND: International collaborative cohorts the NINFEA and the ELF studies are mother-child cohorts that use the internet for recruitment and follow-up of their members. The cohorts investigated the association of early life exposures and a wide range of non-communicable diseases. OBJECTIVE: The objective is to report the research methodology, with emphasis on the advantages and limitations offered by an Internet-based design. These studies were conducted in Turin, Italy and Wellington, New Zealand. METHODS: The cohorts utilized various online/offline methods to recruit participants. Pregnant women who became aware volunteered, completed an online questionnaire, thus obtaining baseline information. RESULTS: The NINFEA study has recruited 7003 pregnant women, while the ELF study has recruited 2197 women. The cohorts targeted the whole country, utilizing a range of support processes to reduce the attrition rate of the participants. For the NINFEA and ELF cohorts, online participants were predominantly older (35% and 28.9%, respectively), highly educated (55.6% and 84.9%, respectively), and were in their final trimester of pregnancy (48.5% and 53.6%, respectively). CONCLUSIONS: Internet-based cohort epidemiological studies are feasible, however, it is clear that participants are self-selective samples, as is the case for many birth cohorts. Internet-based cohort studies are potentially cost-effective and novel methodology for conducting long-term epidemiology research. However, from our experience, participants tend to be self-selective. In marked time, if the cohorts are to form part of a larger research program they require further use and exploration to address biases and overcome limitations.
    No preview · Article · May 2015
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    ABSTRACT: In New Zealand, the burden of childhood obesity is greatest in Māori and Pacific children. In 687 infants from an internet-based birth cohort in New Zealand, we investigated ethnic differences in early life risk factors for later obesity, the degree to which these were explained by sociodemographic factors, and the extent to which ethnic differences in weight at age 3 months were explained by measured risk factors. The risk of having an obese mother was double in Māori and Pacific infants compared with NZ European infants (prevalence 24% and 14%, respectively; OR 2.23, 95% CI 1.23 to 4.04). Māori and Pacific infants had higher weights in the first week of life and at 3 months (mean difference 0.19 kg, 95% CI 0.01 to 0.38), and their mothers had higher scores on a 'snacks' dietary pattern and lower scores on 'healthy' and 'sweet' dietary patterns. These inequalities were not explained by maternal education, maternal age or area-based deprivation. No ethnic differences were observed for maternal pre-pregnancy physical activity, hypertension or diabetes in pregnancy, exclusive breastfeeding or early introduction of solid foods. Ethnic inequalities in infant weight at 3 months were not explained by sociodemographic variables, maternal pre-pregnancy body mass index or dietary pattern scores or by other measured risk factors. This study shows excess prevalence of early life risk factors for obesity in Māori and Pacific infants in New Zealand and suggests an urgent need for early interventions for these groups. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to
    Full-text · Article · Mar 2015 · Journal of epidemiology and community health
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    ABSTRACT: Recently the International Agency for Research on Cancer (IARC) Programme for the Evaluation of Carcinogenic Risks to Humans has been criticized for several of its evaluations, and also the approach used to perform these evaluations. Some critics have claimed that IARC Working Groups' failures to recognize study weaknesses and biases of Working Group members have led to inappropriate classification of a number of agents as carcinogenic to humans. The authors of this paper are scientists from various disciplines relevant to the identification and hazard evaluation of human carcinogens. We have examined here criticisms of the IARC classification process to determine the validity of these concerns. We review the history of IARC evaluations and describe how the IARC evaluations are performed. We conclude that these recent criticisms are unconvincing. The procedures employed by IARC to assemble Working Groups of scientists from the various discipline and the techniques followed to review the literature and perform hazard assessment of various agents provide a balanced evaluation and an appropriate indication of the weight of the evidence. Some disagreement by individual scientists to some evaluations is not evidence of process failure. The review process has been modified over time and will undoubtedly be altered in the future to improve the process. Any process can in theory be improved, and we would support continued review and improvement of the IARC processes. This does not mean, however, that the current procedures are flawed. The IARC Monographs have made, and continue to make, major contributions to the scientific underpinning for societal actions to improve the public's health.
    Full-text · Article · Feb 2015 · Environmental Health Perspectives
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    ABSTRACT: Internet-based systems for epidemiological studies have advantages over traditional approaches as they can potentially recruit and monitor a wider range of individuals in a relatively inexpensive fashion. We studied the association between communication strategies used for recruitment (offline, online, face-to-face) and follow-up participation in nine Internet-based cohorts: the Influenzanet network of platforms for influenza surveillance which includes seven cohorts in seven different European countries, the Italian birth cohort Ninfea and the New Zealand birth cohort ELF. Follow-up participation varied from 43% to 89% depending on the cohort. Although there were heterogeneities among studies, participants who became aware of the study through an online communication campaign compared with those through traditional offline media seemed to have a lower follow-up participation in 8 out of 9 cohorts. There were no clear differences in participation between participants enrolled face-to-face and those enrolled through other offline strategies. An Internet-based campaign for Internet-based epidemiological studies seems to be less effective than an offline one in enrolling volunteers who keep participating in follow-up questionnaires. This suggests that even for Internet-based epidemiological studies an offline enrollment campaign would be helpful in order to achieve a higher participation proportion and limit the cohort attrition.
    Full-text · Article · Dec 2014 · PLoS ONE
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    ABSTRACT: Background Job insecurity has been identified as a risk factor for adverse health outcomes. Perceptions of job insecurity steeply increased during Europe's recent economic downturn, which commenced in 2008. The current study assessed whether job insecurity was associated with incident asthma in Germany during this period. Methods We used prospective data from the German Socio-Economic Panel for the period 2009–2011 (follow-up rate=77.5%, n=7031). Job insecurity was defined by respondents’ ratings of the probability of losing their job within the next 2 years and asthma as self-reports of physician-diagnosed asthma. Associations between job insecurity in 2009 (continuous z-scores or categorised variables) and incident asthma by 2011 were assessed using multivariable Poisson regression. Results The risk of asthma increased significantly by 24% with every one SD increase of the job insecurity variable. In dichotomised analyses, a probability of job loss of ≥50% (vs <50%) was associated with a 61% excess risk of asthma. A trichotomous categorisation of job insecurity confirmed this finding. Conclusions This study has shown, for the first time, that perceived job insecurity may increase the risk of new onset asthma. Further prospective studies may examine the generalisability of our findings and determine the underlying mechanisms.
    Full-text · Article · Sep 2014 · Journal of Epidemiology & Community Health
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    ABSTRACT: Aim: To estimate average infant daily intake of chlorinated persistent organic pollutants (POPs) through the consumption of breast milk in New Zealand. Method: Breast milk of 39 first-time mothers aged 20-30 years was collected during 2007-2010 and analysed for persistent organic pollutants including dioxin-like compounds and organochlorine pesticides. The quantity of POPs consumed by infants assuming exclusive breast feeding was estimated by calculating the Estimated Daily Intake (EDI) expressed as amount consumed through breast milk per kilogram of body weight per day. Results: Of all POPs quantified, the EDI of DDT (principally in the form of its metabolite p,p'-DDE) was the highest (1.6 mcg/kg/day), and above the tolerable daily intake (TDI) of 0.5 mcg/kg/day. The mean EDI for dioxin-like compounds (including PCDD/Fs and PCBs) was 19.7 pg TEQ(toxic equivalency)/kg/day, which is among the lowest reported worldwide, yet above the TDI of 1 pg TEQ/kg/day. The EDI of HCH, HCB, dieldrin, heptachlor and mirex were 32.9, 37.9, 39.4, 2.0, and 0.9 ng/kg/day respectively, all of which were below the current TDI. Age of the mother was positively associated with higher EDIs for the infant, particularly for total-TEQ and total-DDT. Concluison: Infant daily intakes of chlorinated POPs through breast milk estimated for New Zealand are low or average by international comparison, and 5 times lower than 25 years ago. Future breast milk monitoring will determine whether this diminishing trend is continuing as well as providing monitoring information on other POPs.
    No preview · Article · Sep 2014 · The New Zealand medical journal
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    ABSTRACT: OBJECTIVES Significant excess risks of lung cancer and haematologic neoplasms have been observed in slaughterhouse workers in eight New Zealand studies, and numerous studies conducted elsewhere. No specific causal agents have been identified, although a biological aetiology is suggested as the risk is highest in those areas where workers are exposed to live animals or to biological material containing animal urine, faeces or blood. This study aimed to assess the airborne bacterial microflora in the slaughterhouse environment in order to develop exposure categories for reanalysis of a meat workers' cohort. METHOD Bulk air samples (n = 31) were collected for between 5 and 8 h in five areas in both sheep and beef slaughterhouses using a SASS3100 sampler (fitted with a proprietary SASS filter) located between 0.5 and 2 metres from the worker. Nucleic acid was extracted from each filter and amplified using commercially available kits, then sequenced on an Illumina MiSeq instrument. Bioinformatics analyses conducted included comparative taxonomic analyses, gene function (including virulence factor) analyses, and principal component analyses to compare profiles in samples taken in different areas. RESULTS Of the bacteria identified over 95% were in the classes Actinobacteria, Firmicutes and Proteobacteria. Clear differences in all parameters were apparent in the different areas, however, and the full results of the comparative analyses and the development of exposure profiles will be presented. CONCLUSIONS Metagenomic analysis of bioaerosol samples represents a promising method for the development of exposure categories for the epidemiological analysis of the effect of biological exposures in an occupational environment.
    No preview · Article · Jun 2014 · Occupational and Environmental Medicine
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    ABSTRACT: Objectives To provide a detailed assessment of the extent and industrial distribution of workplace carcinogens in New Zealand, and to identify key industries and key carcinogens for which intervention would result in marked reductions in occupational cancer. Method A literature review was conducted identifying the carcinogens present in and the cancer risks associated with each respective industry. A New Zealand specific Information System on Occupational Exposure to Carcinogens (NZ-CAREX) was developed. Results There are more than 50 known human carcinogens commonly present in New Zealand workplaces. The most common of these are: asbestos; benzene; chromium VI compounds; formaldehyde; involuntary smoking; occupational exposures as a painter; silica; solar radiation; wood dust. The industries for which an increased cancer risk has been observed repeatedly in epidemiological studies and have the highest number of potentially exposed workers include: agriculture; construction; health services; machinery and equipment manufacturing; metal product manufacturing; and wood/paper product manufacturing. Of the agricultural chemicals currently in use in New Zealand’s agricultural sector, none are known human carcinogens, but numerous are suspected to be carcinogenic to humans. A number of barriers for the implementation of intervention strategies were identified, which could be removed by improving access to knowledge regarding the occurrence of carcinogens in New Zealand workplaces and improving access to control tools and methods to evaluate their effectiveness. Conclusions Exposure to carcinogens remains common in New Zealand workplaces, and many opportunities remain for reducing exposure and the associated occupational cancer burden.
    No preview · Article · Jun 2014 · Occupational and Environmental Medicine
  • Article: Asthma
    Neil Pearce · Jeroen Douwes

    No preview · Article · Dec 2013
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    ABSTRACT: Published studies have shown that workers in animal slaughterhouses are at a higher risk of lung cancers as compared to the general population. No specific causal agents have been identified, and exposures to several chemicals have been examined and found to be unrelated. Evidence suggests a biological aetiology as the risk is highest for workers who are exposed to live animals or to biological material containing animal faeces, urine or blood. To investigate possible biological exposures in animal slaughterhouses, we used a metagenomic approach to characterise the profile of organisms present within an aerosol sample. An assessment of aerosol exposures for individual workers was achieved by the collection of personal samples that represent the inhalable fraction of dust/bioaerosol in workplace air in both cattle and sheep slaughterhouses. Two sets of nine personal aerosol samples were pooled for the cattle processing and sheep processing areas respectively, with a total of 332,677,346 sequence reads and 250,144,492 sequence reads of 85 bp in length produced for each. Eukaryotic genome sequence was found in both sampling locations, and bovine, ovine and human sequences were common. Sequences from WU polyomavirus and human papillomavirus 120 were detected in the metagenomic dataset from the cattle processing area, and these sequences were confirmed as being present in the original personal aerosol samples. This study presents the first metagenomic description of personal aerosol exposure and this methodology could be applied to a variety of environments. Also, the detection of two candidate viruses warrants further investigation in the setting of occupational exposures in animal slaughterhouses.
    Full-text · Article · Aug 2013 · PLoS ONE
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    ABSTRACT: Polybrominated diphenyl ethers (PBDEs) are present in many consumer goods. There is evidence that PBDEs are toxic to humans, particular young children. The purpose of this study was to assess indoor dust as an exposure source for PBDEs. Concentrations of 16 PBDEs were determined in dust samples from 33 households in New Zealand, and in breast milk samples from 33 mothers living in these households. Associations between dust and breast milk PBDE concentrations were assessed, and children's PBDE intake from breast milk and dust estimated. Influences of household and demographic factors on PBDE concentrations in dust were investigated. Indoor dust concentrations ranged from 0.1ng/g for BDE17 to 2500ng/g for BDE209. Breast milk concentrations were positively correlated (p<0.05) with mattress dust concentrations for BDE47, BDE153, BDE154, and BDE209 and with floor dust for BDE47, BDE183, BDE206, and BDE209. The correlation for BDE209 between dust and breast milk is a novel finding. PBDE concentrations in floor dust were lower from households with new carpets. The estimated children's daily intake of PBDEs from dust and breast milk was below U.S. EPA Reference Dose values. The study shows that dust is an important human exposure source for common PBDE formulations in New Zealand.
    No preview · Article · Jul 2013 · Environment international
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    ABSTRACT: Background and objectiveIncreased sputum neutrophilia has been observed in asthma, but also during normal ageing in asthmatics and non-asthmatics. It remains unclear what constitutes ‘normal’ neutrophil levels in different age groups. Methods We assessed the relationship between age and airway neutrophils of 194 asthmatics and 243 non-asthmatics (age range: 6–80 years). Regression analyses were used to assess this relationship adjusted for confounders including asthma status, atopy, gender, smoking and current use of inhaled corticosteroids (ICS). Age-corrected reference values for different age groups were determined using the 95th percentile of non-asthmatic participants. ResultsAge was positively associated with sputum neutrophils in both asthmatic and non-asthmatic adults (0.46% neutrophil increase/year (95% confidence interval (CI) 0.18, 0.73) and 0.44%/year (0.25, 0.64, respectively), but no association was found in the <20-year age category. Individuals with high sputum neutrophil counts (>95th percentile of non-asthmatic counts for any given age group) were significantly more likely to be asthmatic (odds ratio = 2.5; 95% CI: 1.3, 5.0), with the greatest effect observed in the older age group. Other factors that independently associated with increased sputum neutrophil levels included atopy in non-asthmatic adults, male gender and current use of ICS in asthmatic adults. Age-specific reference values for neutrophil percentage were under 20 years-76%, 20–40 years-62%, 40–60 years-63% and over 60 years-67%. Conclusions Airway neutrophilia is related to age in adults, with a neutrophilic asthma phenotype present in older adults. The use of appropriate age-specific reference values is recommended for future studies aimed at elucidating the role of neutrophils in asthma.
    No preview · Article · Jul 2013 · Respirology
  • Neil Pearce · Jeroen Douwes
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    ABSTRACT: Epidemiology is currently undergoing changes in its underlying philosophy and approach, as a result of the rapid global changes which are transforming the world in which epidemiologists live and work. This necessitates a multidisciplinary "population approach" involving "multilevel thinking" about the determinants of disease. These issues are of relevance to the interface between human and animal epidemiology, which has received considerable attention in recent years, particularly as a result of the arrival of H1N1 influenza, and the increasingly obvious need for coordinated systems of surveillance for human and animal infectious diseases. However, the need for coordination between human and veterinary epidemiology is broader than that, and there is no need to restrict the "one world one health" concept to communicable disease. In the current paper we will therefore consider the interface between human and animal health for the study of non-communicable disease, particularly those involving occupational and environmental risk factors. These issues are illustrated with two examples: one involving environmental health (asthma); and one involving occupational health (cancer). We will also discuss the potential to use animal health data as indicators for human environmental health risks.
    No preview · Article · Jun 2013 · Preventive Veterinary Medicine
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    ABSTRACT: Breast milk samples of 39 first time mothers aged 20-30 were collected in 2007-2010 from rural and urban areas of New Zealand, following the fourth World Health Organization coordinated survey protocol. Samples were individually analysed for persistent organic pollutants (POPs) including dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). The lipid adjusted concentrations of PCDD/Fs (mean toxic equivalent (TEQ): 3.54pg/g) and PCBs (mean TEQ 1.29pg/g) were low in comparison to those reported for other countries, and concentrations of dieldrin (10ng/g) and p,p'-DDE (379ng/g) and PBDEs were in the mid-range. Breast milk concentrations of PCDD/F-TEQ, PCB-TEQ, dieldrin and p,p'-DDE were significantly higher in rural compared to urban areas (+23%, 33%, 59%, and 44% respectively), while concentrations of several PBDEs and lindane were higher in urban areas. Concentrations of PCDD/Fs, PCBs and OCPs, but not PBDEs, increased with age, and higher body mass index was associated with lower concentrations of PCBs. Despite New Zealand's low body burdens of many chlorinated POPs in comparison to other countries, breast milk concentrations continued to decrease over time, with a decrease by half over the last 10years for PCDD/F-TEQ (-40%), PCB-TEQ (-54%) and OCPs -34 to -90%), indicating that regulatory measures continue to have beneficial effects. Continued monitoring is needed particularly for the brominated POPs for which little New Zealand specific data is available.
    No preview · Article · May 2013 · Science of The Total Environment
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    ABSTRACT: Background. Asthma and depression are important public-health concerns worldwide. While some epidemiologic studies have shown asthma and wheezing to be associated with depression and anxiety, the patterns are unclear at the multinational level due to the lack of cross-study comparability. Our study examined the associations of self-reported asthma diagnosis and current wheezing with self-reported depression diagnosis and 30-day anxiety using an international survey. Methods. Using the 2002 World Health Survey, a standardized international survey conducted by the WHO, we estimated the associations between diagnosed asthma and current wheezing with diagnosed depression and 30-day anxiety via multiple logistic regressions for 54 countries worldwide. Results. Diagnosed depression and 30-day anxiety were associated with diagnosed asthma in 65% and 40% of the countries, respectively. Diagnosed depression and 30-day anxiety were associated with current wheezing in 83% and 82% of the countries, respectively. Conclusions. The association between asthma and depression was generally seen at the global level. These results indicated the importance of addressing the asthma-depression comorbidity as public-health and clinical management priorities, in order to improve the overall health of the countries.
    Full-text · Article · Mar 2013 · Pulmonary Medicine
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    ABSTRACT: Background: Airway inflammation is commonly assessed by sputum induction followed by a differential cell count (DCC) using light microscopy. This method is prone to intercounter variability and poor reproducibility. We aimed to develop a more objective method using flow cytometry (FCM). Methods: Fifty-six sputum inductions were conducted in 41 adults (23 asthmatics). Sputum was processed, a cytospin prepared for DCC, and the remainder immunolabeled for FCM using CD45, CD14, and CD16-specific antibodies to distinguish major leukocyte populations. Aliquots of 15 samples were frozen at -80°C to assess the effects of cryostorage. DCC and FCM were compared, and viability of individual cell populations was determined by FCM. Results: FCM and DCC, and fresh and frozen samples, were significantly correlated, R = 0.54-0.87; all P < 0.0001, and R = 0.57 to 1; P < 0.005, respectively. There was a significant neutrophil loss after cryostorage (from median 30.5-17.4% of total leukocytes; P < 0.0001). Cell viability was higher for lymphocytes compared to granulocytes or macrophages (P < 0.001). With the exception of the expected higher levels of eosinophils (P < 0.005), no significant difference in cell differentials or viability was observed between asthmatics and nonasthmatics using either DCC or FCM. Conclusions: FCM is a suitable means of assessing leukocyte populations in induced sputum. Sample storage at -80°C prior to FCM is feasible, but may be detrimental to neutrophils, although good correlations were still observed between fresh and frozen samples. Large differences in viability were found between individual cell populations suggesting that viability dye use may be necessary.
    No preview · Article · Mar 2013 · Cytometry Part B Clinical Cytometry

Publication Stats

7k Citations
601.51 Total Impact Points


  • 2003-2016
    • Massey University
      • Centre for Public Health Research
      Palmerston North City, Manawatu-Wanganui, New Zealand
    • Erasmus Universiteit Rotterdam
      Rotterdam, South Holland, Netherlands
  • 2000-2009
    • Utrecht University
      • Institute for Risk Assessment Sciences (IRAS)
      Utrecht, Utrecht, Netherlands
    • University of Iowa
      • College of Public Health
      Iowa City, Iowa, United States
    • Kuopio University Hospital
      • Department of Pulmonary Diseases
      Kuopio, Northern Savo, Finland
  • 2004
    • National Institute of Occupational Health (STAMI)
      • Department of Chemical and Biological Work Environment
      Kristiania (historical), Oslo County, Norway
  • 2001
    • Columbia University
      • Department of Environmental Health Sciences
      New York City, NY, United States
  • 1995-2000
    • Wageningen University
      • Sub-department of Environmental Technology
      Wageningen, Gelderland, Netherlands
  • 1996-1997
    • University of Amsterdam
      • Department of Molecular Cell Biology
      Amsterdamo, North Holland, Netherlands