Exhaled nitric oxide and spirometry in respiratory health surveillance

Phthalates Exposure and Occupational Symptoms among Slovakian Hairdressing Apprentices

The objectives of the study were to examine occupational exposure to phthalates of hairdressing apprentices from Slovakia (n = 74, 89.2% females; 10.8% males), outcomes related to body composition and pulmonary functions. We used high-performance liquid chromatography and tandem mass spectrometry to the quantified urinary concentration of phthalates. Pulmonary function test (PFT), anthropometric measurements, and questionnaire were also conducted. We observed a decrease of % of predicted values of forced vital capacity (FVC% of PV) related exposure to mono(2-ethyl-5-oxohexyl) phthalate (MEOHP; p = 0.054) and sum of bis(2-ethylhexyl) phthalate metabolites (∑DEHP; p = 0.037), and a decrease of % of predicted values of vital capacity (VC% of PV) related to exposure to MEOHP, ∑DEHP (p = 0.008), and mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP; p = 0.014) in females. We detected associations between forced vital capacity (FVC) with weight (p = 0.002) and fat-free mass index (FFMI, p = 0.010). Vital capacity (VC) and VC% of PV increased with weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), waist-hip ratio (WHR), the waist-height ratio (WHtR), fat mass index (FMI) and FFMI in females (p ≤ 0.014). Results of multivariate regression between PFT and anthropometric parameters adjusted to phthalates indicated exposure to MnBP and MEHP, changing body structure (BMI and FMI), subsequently affecting values of FEV1/FVC.

Health surveillance for occupational asthma

PURPOSE OF REVIEW

The outcome for workers with occupational asthma is improved for those with an earlier diagnosis. Health surveillance at work is in principle designed to identify such cases, so that the risks to the individual worker, and coworkers, can be reduced. There is recent evidence to suggest that the uptake and quality of such surveillance could be improved. This review has assessed current approaches to health surveillance for occupational asthma.

RECENT FINDINGS

The article covers a review of the utility of questionnaires, lung function testing, immunological investigations, and other tests, including exhaled nitric oxide, sputum eosinophilia, and exhaled breath condensate specifically in the context of workplace-based health surveillance.

SUMMARY

Questionnaires remain a key component of respiratory health surveillance, although maybe limited by both sensitivity and specificity for early occupational asthma. The role of lung function testing is debated, although is recommended for higher level health surveillance. Various examples of immunological testing in health surveillance are discussed, but more evidence is needed in many specific areas before more general recommendations can be made. Evidence is discussed in relation to the utility of newer approaches such as exhaled nitric oxide, sputum eosinophilia, and exhaled breath condensate.

Environmental factors associated with baseline and serial changes in fractional exhaled nitric oxide (FeNO) in spice mill workers

BACKGROUND

This study evaluated the determinants of high fractional exhaled nitric oxide (FeNO; >50 ppb) and serial changes in FeNO over a 24-hour period in spice mill workers at risk of work-related allergic respiratory disease and asthma.

METHODS

A cross-sectional study of 150 workers used European Community Respiratory Health Survey (ECRHS) questionnaires, Phadiatop, serum-specific IgE (garlic, chilli pepper, wheat; Phadia, ImmunoCAP), spirometry and FeNO. A hand-held portable nitric oxide sampling device (NIOX MINO, Aerocrine AB) measured FeNO before and after the 8-hour shift and after 24 hours from baseline.

RESULTS

The mean age of workers was 33 years; 71% were male, 46% current smokers and 45% atopic. Among workers with garlic sensitisation, 13% were monosensitised and 6% were co-sensitised to chilli pepper. Baseline preshift FeNO geometric mean (GM=14.9 ppb) was similar to the mean change across shift (GM=15.4 ppb) and across the 24-hour period (GM=15.8 ppb). In multivariate linear models, smoking (β=-0.507) and atopy (β=0.433) were strongly associated with FeNO. High FeNO (>50 ppb) was significantly associated with asthma-like symptoms due to spice dust (OR=5.38, CI 1.01 to 28.95). Sensitisation to chilli pepper was more strongly correlated with FeNO (r=0.32) and FeNO>50 ppb (OR=17.04, p=0.005) than garlic. FeNO increase (>12%) across 24 hours demonstrated a strong association with elevated exposures to spice dust particulate (OR=3.77, CI 1.01 to 14.24).

CONCLUSIONS

This study suggests that chilli pepper sensitisation is associated with high FeNO (>50 ppb), more strongly compared with garlic, despite the low prevalence of sensitisation to chilli. Elevated inhalant spice dust particulate is associated with a delayed elevation of FeNO across the 24-hour period.

Endotoxin, dust and exhaled nitrogen oxide among hand pickers of coffee; a cross-sectional study

BACKGROUND

Primary coffee processing takes place in countries where coffee is grown, and may include hand picking of coffee to remove low quality beans. Hand picking is mostly performed by women. No previous studies on dust and respiratory health have been performed in this occupational group, although studies indicate respiratory problems among other coffee production workers.

FINDINGS

Our aim was to assess dust and endotoxin exposure among hand pickers in a coffee factory and compare the levels with limit values. In addition we wanted to examine the fraction of exhaled nitric oxide (FeNO) as a possible inflammatory marker in the airways among the hand pickers and evaluate the association between FeNO and years of hand picking. All hand pickers in a factory were examined during 1 week. The response was 100 %; 69 participated. FeNO was measured using an electrochemistry-based NIOX MINO device. Nine out of 69 workers (13 %) had levels of FeNO above 25 ppb, indicating presence of respiratory inflammation. A significant positive association was found between increasing FeNO and years of hand picking. Nine personal samples of total dust and endotoxin were taken. None of the dust samples exceeded the occupational limit value for total organic dust of 5 mg/m(3). Three samples of endotoxin (33 %) were above the recommended value of 90 EU/m(3).

CONCLUSIONS

Levels of endotoxin were higher than recommended standards among hand pickers, and there was a positive association between the level of exhaled nitrogen oxide and years of work with hand picking coffee.

Contribution of exhaled nitric oxide measurement in airway inflammation assessment in asthma. A position paper from the French Speaking Respiratory Society

Nitric oxide (NO) is both a gas and a ubiquitous inter- and intracellular messenger with numerous physiological functions. As its synthesis is markedly increased during inflammatory processes, NO can be used as a surrogate marker of acute and/or chronic inflammation. It is possible to quantify fractional concentration of NO in exhaled breath (FENO) to detect airway inflammation, and thus improve the diagnosis of asthma by better characterizing asthmatic patients with eosinophilic bronchial inflammation, and eventually improve the management of targeted asthmatic patients. FENO measurement can therefore be viewed as a new, reproducible and easy to perform pulmonary function test. Measuring FENO is the only non-invasive pulmonary function test allowing (1) detecting, (2) quantifying and (3) monitoring changes in inflammatory processes during the course of various respiratory disorders, including corticosensitive asthma.

Fractional exhaled nitric oxide in the interpretation of specific inhalational challenge tests for occupational asthma

PURPOSE

Fractional exhaled nitric oxide (FENO) measurements are recommended for the assessment of eosinophilic airway inflammation in asthma. Clinically relevant increases in FENO have been reported 24 h after positive specific inhalational challenge (SIC) tests in occupational asthma. We aimed to determine whether positive SICs could be discriminated from control tests, on the basis of change in FENO.

METHODS

We reviewed all positive SICs to a variety of agents performed at our institution 2008-2012 and gathered data on age, sex, asthmatic response (immediate/dual/late), smoking status, inhaled corticosteroid usage, and FENO pre- and 24-h postcontrol and positive SIC from each worker. Changes in FENO after positive SICs were compared with control SICs from each worker, by using paired Student's t tests.

RESULTS

In 16 workers, negative control challenges were associated with mean changes in FENO of 9 % (95 % CI -1.14 to 19.01) or 1.1 ppb (95 % CI -3.59 to 5.84); 2 of 16 (13 %) workers tested showed increases in FENO that were clinically relevant based on recent guidelines. Subsequent positive SICs were associated with mean changes in FENO of 7 % (95 % CI −15.73 to 29.6) or 2.1 ppb (95 % CI -6.07 to 10.19), which were not significantly different to controls; only 2 of 16 (13 %) workers had FENO changes that were clinically relevant.

CONCLUSIONS

FENO changes above the upper confidence limits of ≥20 % or ≥6 ppb may be considered to be outside the range of normality. However, the majority of workers who had clearly positive SICs to common low molecular weight agents also had no statistically or clinically relevant increase in FENO. Therefore, change in FENO does not predict a positive SIC in this group.

Health surveillance for occupational respiratory disease

BACKGROUND

Occupational lung diseases remain common, and health surveillance is one approach used to assist identification of early cases.

AIMS

To identify areas of good practice within respiratory health surveillance and to formulate recommendations for practice.

METHODS

Published literature was searched since 1990 using a semi-systematic methodology.

RESULTS

A total of 561 documents were identified on Medline and Embase combined. Other search engines did not identify relevant documents that had not already been identified by these two main searches. Seventy-nine of these were assessed further and 36 documents were included for the full analysis.

CONCLUSIONS

Respiratory health surveillance remains a disparate process, even within disease type. A standard validated questionnaire and associated guidance should be developed. Lung function testing was common and generally supported by the evidence. Cross-sectional interpretation of lung function in younger workers needs careful assessment in order to best identify early cases of disease. More informed interpretation of the forced expiratory volume in 1 s/forced vital capacity ratio, for example by using a lower limit of normal for each worker, and of longitudinal lung function information is advised. Immunological tests appear useful in small groups of workers exposed to common occupational allergens. Education, training and improved occupational health policies are likely to improve uptake of health surveillance, to ensure that those who fail health surveillance at any point are handled appropriately.

Medical surveillance for prevention of occupational asthma

PURPOSE OF REVIEW

Because there is sufficient knowledge of its environmental determinants, occupational asthma is a disease that ought to be largely preventable; yet its incidence in many settings remains unacceptably high. Here we review one approach to prevention: the routine use of health surveillance in exposed workforces.

RECENT FINDINGS

Health surveillance is widely practised but there is little evidence that it is used strategically to reduce disease incidence. There are several barriers to the effective use of its various components, chiefly symptoms questionnaires and spirometry. Cost-benefit analyses may help to increase the uptake of industry-wide workplace interventions.

SUMMARY

The effective use of health surveillance for occupational asthma continues to be challenging and there remains relatively little published evidence that will encourage those involved to use it more efficiently. Useful advances could be made by greater collaboration between employers, employee organizations, legislators and researchers.