Healthy hire effect, job selection and inhalation exposure among young adults with asthma

Impact of asthma on working life: an analysis of the French CONSTANCES cohort

OBJECTIVES

Asthma has significant occupational consequences. The objective of our study was to investigate the links between asthma and the career path, taking into account gender and age at asthma onset.

METHODS

Using cross-sectional data collected at inclusion in the French CONSTANCES cohort in 2013-2014, we studied the links between each career path indicator (number of job periods, total duration of employment, numbers of part-time jobs and work interruptions due to unemployment or health issues, employment status at inclusion) on the one hand, and current asthma and asthma symptom score in the last 12 months on the other hand, as reported by the participants. Multivariate analyses were performed separately for men and women using logistic and negative binomial regression models adjusted for age, smoking status, body mass index and educational level.

RESULTS

When the asthma symptom score was used, significant associations were observed with all of the career path indicators studied: a high symptom score was associated with a shorter total duration of employment as well as a greater number of job periods, part-time jobs and work interruptions due to unemployment or health issues. These associations were of similar magnitude in men and women. When current asthma was used, the associations were more pronounced in women for some career path indicators.

CONCLUSION

The career path of asthmatic adults is more often unfavourable than that of those without asthma. Efforts should be made to support people with asthma in the workplace, in order to maintain employment and facilitate the return to work.

Association of Childhood Respiratory Status with Adult Occupational Exposures in a Birth Cohort

Rationale: People with better early-life respiratory health may be more likely to work in occupations with high workplace exposures in adult life compared with people with poor respiratory health. This may manifest as a healthy worker effect bias, potentially confounding the analysis of environmental exposure studies. Objectives: To evaluate associations between lung function in adolescence and occupational exposures at initial adult employment. Methods: The TCRS (Tucson Children's Respiratory Study) is a long-term prospective study of respiratory health beginning at birth. Associations between respiratory function at age 11 years and occupational exposures at first job at age 26 years were evaluated with logistic regression. We calculated percentage predicted values for forced expiratory volume in one second (FEV1), forced vital capacity (FVC), FEV1:FVC ratio, and forced expiratory flow from 25% to 75% of vital capacity at age 11. At the 26-year visit, participants self-reported occupational exposures to dust, smoke, and fumes/gas at first job in a standardized interview. Results: Forced expiratory flow from 25% to 75% of vital capacity and FEV1:FVC ratio at age 11 were positively associated with dust workplace exposures at the first job. Each 10% increase in percentage predicted prebronchodilator FEV1:FVC ratio was associated with 30% higher odds of workplace dust exposure (odds ratio for a 1% increase, 1.03 [95% confidence interval, 1.00-1.06; P = 0.045]). Similar associations were observed for FEV1 and FVC with workplace smoke exposures. We also observed modification by time at job: associations were stronger for those who remained in their jobs longer than 12 months. In addition, those with better function at age 11 were more likely to stay in their jobs longer than 12 months if their first jobs involved exposure to dust. Conclusions: Childhood lung function affects initial career choice. This study supports the premise of the healthy worker effect.

Exposure to additives or multigrain flour is associated with high risk of work-related allergic symptoms among bakers

OBJECTIVES

Wheat flour exposure in bakers can elicit respiratory and skin symptoms. Scarce data are available on the prevalence of such conditions in bakers. We investigated the prevalence of work-related rhinitis, asthma-like symptoms and dermatitis in bakers according to job task and type of allergens involved.

METHODS

Of the 229 traditional bakeries in Verona area who were invited to participate in a cross-sectional survey, 211 (92%) accepted; 727 employees in these bakeries answered a modified version of a questionnaire on job tasks; allergen exposure within the bakery; and work-related nasal, asthma-like and skin symptoms during 2010-2014. Determinants of work-related nasal, asthma-like or skin disorders were separately evaluated using different logistic models.

RESULTS

The prevalence of work-related nasal and asthma-like symptoms was, respectively, 15.1% and 4.2% in bakery shop assistants, increasing to 25.7% and 9.5% in bakers using only wheat flour, and further to 31.8% and 13.6% in bakers using flour and additives, and then to 34.1% and 18.2% in bakers using flour with additives and multigrain (p<0.001). The risk of work-related asthma-like symptoms was more than doubled in bakers using additives without or with multigrain than in shop assistants (OR 2.3, 95% CI 1.0 to 5.5 and OR 3.4, 95% CI 1.1 to 10.8, respectively). Making bread with additives alone or with multigrain significantly increased the risk of work-related nasal symptoms in shop assistants, while the risk of skin symptoms was not significantly affected.

CONCLUSIONS

Bakers using additives alone or with multigrain are at a high risk of experiencing nasal and asthma-like symptoms.

Influence of Childhood Asthma and Allergies on Occupational Exposure in Early Adulthood: A Prospective Cohort Study

We aimed to determine whether history of asthma/allergies in childhood was associated with avoidance of jobs with exposure to asthmagens in early adulthood. The Melbourne Atopic Cohort Study recruited 620 children at high risk of allergic diseases at birth (1990–1994). Asthma, hay fever and eczema were evaluated by questionnaires during childhood. A follow-up in early adulthood (mean age: 18 years) collected information on the current job. Occupational exposure to asthmagens/irritants was evaluated using a job-exposure matrix. The association between history of asthma/allergies in childhood and working in a job with exposure to asthmagens/irritants was evaluated by logistic regression, adjusted for age, sex and parental education. Among 363 participants followed-up until early adulthood, 17% worked in a job with exposure to asthmagens/irritants. History of asthma (35%) was not associated with working in an exposed job (adjusted OR: 1.16, 95% CI: 0.65–2.09). Subjects with history of hay fever (37%) and eczema (40%) were more likely to enter exposed jobs (significant for hay fever: 1.78, 1.00–3.17; but not eczema: 1.62, 0.91–2.87). In conclusion, young adults with history of allergies were more likely to enter exposed jobs, suggesting no avoidance of potentially hazardous exposures. Improved counselling against high risk jobs may be needed for young adults with these conditions.

Do young adults with atopic dermatitis avoid harmful workplace exposure at their first job? A prospective cohort study

PURPOSE

Patients with atopic dermatitis (AD) are at high risk of chronic hand eczema. In this prospective cohort study, we assessed the influence of pre-hire-onset AD on the first job choice. We also analysed the potential association between AD and usage of preventive measures in high-risk occupations.

METHODS

Subjects (aged 19-24 years) who were followed from childhood until the second Study on Occupational Allergy Risks and indicated a job were included (n = 1566). We defined AD as doctor-diagnosed AD and symptoms of an itchy rash during the past 12 months before the study. Pre-hire-onset AD was having AD prior to the first job. Preventive measure usage was self-reported gloves use or use of ointment or moisturizer. We performed multiple imputations to deal with missing values and analysed associations using logistic regression models adjusted for several potential confounders.

RESULTS

Risk categories of the first job did not differ between participants with pre-hire-onset AD and those without (odds ratio 1.05, 95 % confidence interval 0.59-1.87). AD status was not statistically significantly associated with usage of preventive measures (1.22, 0.56-2.64). Conversely, having received job counselling (2.76, 1.15-6.63) and a family history of AD (2.09, 1.01-4.31) were associated with a higher use of such measures.

CONCLUSION

We could not confirm a healthy hire effect in this cohort of young adults. Although subjects with AD in high-risk occupations do not seem to use more preventive measures than their non-affected peers, job counselling seems to be an effective approach to encourage secondary prevention.

Asthma history, job type and job changes among US nurses

OBJECTIVES

Nurses are at increased risk of occupational asthma, an observation that may be related to disinfectants exposure. Whether asthma history influences job type or job changes among nurses is unknown. We investigated this issue in a large cohort of nurses.

METHODS

The Nurses' Health Study II is a prospective study of US female nurses enrolled in 1989 (ages 24-44 years). Job status and asthma were assessed in biennial (1989-2011) and asthma-specific questionnaires (1998, 2003). Associations between asthma history at baseline (diagnosis before 1989, n=5311) and job type at baseline were evaluated by multinomial logistic regression. The relations of asthma history and severity during follow-up to subsequent job changes were evaluated by Cox models.

RESULTS

The analytic cohort included 98 048 nurses. Compared with nurses in education/administration (likely low disinfectant exposure jobs), women with asthma history at baseline were less often employed in jobs with likely high disinfectant exposure, such as operating rooms (odds ratio 0.73 (95% CI 0.63 to 0.86)) and emergency room/inpatient units (0.89 (0.82 to 0.97)). During a 22-year follow-up, nurses with a baseline history of asthma were more likely to move to jobs with lower exposure to disinfectants (HR 1.13 (1.07 to 1.18)), especially among those with more severe asthma (HR for mild persistent: 1.13; moderate persistent 1.26; severe persistent: 1.50, compared with intermittent asthma, p trend: 0.004).

CONCLUSIONS

Asthma history was associated with baseline job type and subsequent job changes among nurses. This may partly reflect avoidance of tasks involving disinfectant use, and may introduce bias in cross-sectional studies on disinfectant exposure and asthma in nurses.

Employed adults with asthma who have frequent workplace exposures

Abstract Objective: The recent increase in asthma prevalence is thought to be partially due to environmental changes such as changes in air pollution and occupational exposures. Nationally representative information on workplace exposures among US adults with asthma is limited.

METHODS

We examined 2010 National Health Interview Survey data to determine the proportion of employed adults with asthma who had frequent workplace exposures.

RESULTS

Among adults with current asthma, 19.6% frequently worked outdoors, 17.5% were frequently exposed to workplace secondhand smoke and 28.1% were frequently exposed to workplace vapors, gas, dust or fumes. Adults ever told by a health professional that asthma is probably work-related, when compared to adults who were not, had increased odds of frequent work outdoors [prevalence odds ratio (POR)=2.76], frequent workplace exposure to secondhand smoke (POR=3.08) and frequent workplace exposure to vapors, gas, dust or fumes (POR=3.56).

CONCLUSIONS

To our knowledge, this is the first population-based study in USA that estimates the proportion of working adults with asthma that have frequent workplace exposures. Increasing the understanding of workplace exposures among adults with asthma will help enable prevention of asthma through workplace exposure reduction or avoidance. Future studies should further examine industries and occupations of individuals with asthma and frequent workplace exposures.

Occupational exposures and the development of new-onset asthma: a population-based cohort study from the ages of 13 to 44 years

OBJECTIVE

To evaluate the risk of asthma associated with occupational exposures in a population-based cohort.

METHODS

The risk of asthma was analyzed in 792 subjects who were asthma free at the age of 13 years. Occupational histories were obtained from subjects at the age of 44 years and occupational exposures determined with an asthma-specific job exposure matrix. Cumulative exposure to latex and risk of asthma was examined using Cox proportional hazards regression.

RESULTS

Development of asthma was modestly related to exposure at any time to high molecular weight latex (odds ratio, 1.4; 95% confidence interval, 0.9-2.3). Cumulative latex exposure of 6 to 15 years was associated with a hazard ratio of 1.6 for the development of asthma and after 16 years increased to 2.65 (95% confidence interval, 1.28-5.47).

CONCLUSION

There is a significant association between cumulative occupational exposure to latex and new-onset asthma.

Work related asthma. A causal analysis controlling the healthy worker effect

OBJECTIVES

The healthy worker effect usually leads to underestimation of the association between occupational exposure and asthma. The role of irritants in work-related asthma is disputed. We estimated the effect of occupational exposure on asthma expression in a longitudinal study, using marginal structural modelling to control for the healthy worker effect.

METHODS

Analyses included 1284 participants (17-79 years, 48% men) from the follow-up (2003-2007) of the French Epidemiological study on the Genetics and Environment of Asthma (case-control study). Age at asthma onset, periods with/without attacks over lifetime and occupational history were recorded retrospectively. Exposures to known asthmagens, irritants or low level of chemicals/allergens were evaluated through a job-exposure matrix. The job history was reconstructed into 5-year intervals.

RESULTS

Thirty-one per cent of subjects had ever been exposed to occupational asthmagens. Among the 38% of subjects who had asthma (ever), presence of attacks was reported in 52% of all time periods. Using standard analyses, no association was observed between exposure to known asthmagens (OR (95% CI): 0.99 (0.72 to 1.36)) or to irritants/low level of chemicals/allergens (0.82 (0.56 to 1.20)) and asthma attacks. Using a marginal structural model, all associations increased with suggestive evidence for known asthmagens (1.26 (0.90 to 1.76)), and reaching statistical significance for irritants/low level of chemicals/allergens (1.56 (1.02 to 2.40)).

CONCLUSIONS

The healthy worker effect has an important impact in risk assessment in work-related asthma studies. Marginal structural models are useful to eliminate imbalances in exposure due to disease-driven selection. Results support the role of irritants in work-related asthma.

Exacerbation of symptoms in agricultural pesticide applicators with asthma

PURPOSE

Exacerbation is a critical event in asthma management. We investigated whether exacerbation of symptoms is associated with farming exposures among agricultural pesticide applicators with asthma.

METHODS

Participants were pesticide applicators with active asthma (wheezing and breathing problems in past 12 months) who completed enrollment questionnaires for the Agricultural Health Study (AHS). Exacerbation of asthma was defined as having visited a hospital emergency room or doctor for an episode of wheezing or whistling in the past 12 months. Exposures of interest were using 36 specific pesticides in the past 12 months and conducting various agricultural activities. Adjusted odds ratios (ORs) were estimated by logistic regression while controlling for potential confounders.

RESULTS

The 926 AHS adult pesticide applicators with active asthma included 202 (22%) with exacerbation. Inverse associations with exacerbation were observed for two herbicides [glyphosate, odds ratio (OR) = 0.5, 95% confidence interval (CI) 0.3, 0.8, and paraquat, OR = 0.3, 95% CI 0.1, 0.9] and several agricultural activities (repairing engines, grinding metal, driving diesel tractors, and performing veterinary procedures). Only asthma cases with allergies (i.e., doctor-diagnosed hay fever or eczema, 46%) had positive exacerbation-pesticide associations, with OR = 2.1 (95% CI 1.1, 4.1) for the herbicide pendimethalin and OR = 10.2 (95% CI 1.9, 55) for the insecticide aldicarb.

CONCLUSIONS

The inverse associations with two pesticides and specific farm activities are consistent with the possibility that asthma cases prone to exacerbation may avoid exposures that trigger symptoms. Although limited by small sample size and a cross-sectional design, our study suggests that use of specific pesticides may contribute to exacerbation of asthma among individuals with allergies.

Predictors of respiratory sickness absence: an international population-based study

BACKGROUND

Respiratory tract-related occupational disability is common among adults of working age. We examined occupational vapors, gas, dust, or fume (VGDF) exposure as a predictor of disability, based on respiratory sickness absence among the actively employed, at an early point at which prevention may be most relevant.

METHODS

Currently employed European Community Respiratory Health Survey II participants (n = 6,988) were classified into three mutually exclusive, condition/symptom-based categories: physician-diagnosed asthma, self-reported rhinitis, and wheeze/breathlessness (n = 4,772). Logistic regression analysis estimated the odds of respiratory sickness absence (past 12 months) by VGDF exposure.

RESULTS

In the condition/symptom groups, 327 (6.9%) reported respiratory sickness absence. Exposure to VGDF was associated with increased odds of respiratory sickness absence: asthma odds ratio [OR] 2.0 (95% confidence interval [CI] 1.1-3.6), wheeze/breathlessness OR 2.2 (95% CI 1.01-4.8); rhinitis OR 1.9 (95% CI 1.02-3.4).

CONCLUSION

One in 15 currently employed with asthma, breathlessness, or rhinitis reported respiratory sickness absence. VGDF exposure doubled the odds of respiratory sickness absence, suggesting a focus for disability prevention.

Respiratory symptoms and respiratory-related absence from work among health care workers in Sweden

OBJECTIVE

To investigate respiratory symptoms and respiratory-related absence from work among Swedish health care workers (HCWs).

METHODS

From a postal questionnaire study among a general Swedish working population (n = 12,186), we identified 2156 HCW (555 assistant nurses, 377 nurses, 109 physicians, and 1115 others), including 429 with mainly cleaning tasks (HCW-cleaning). The remaining respondents were classified as non-HCW. Multiple logistic regressions with 95% confidence intervals (CIs) were used to compare respiratory symptoms and respiratory-related absence from work between HCW and non-HCW, adjusting for potential confounders.

RESULTS

The prevalence of adult onset asthma was 4.3% in HCW and 3.0% in non-HCW (p = .003). Asthmatic symptoms during the past year were reported mainly by HCW-cleaning, 14.7%, in comparison to 8.3% among non-HCW (p < .0001). HCW had an increased odds ratio (OR) for asthmatic symptoms during the past year (OR 1.3, 95% CI (1.1-1.5)) and more prominent among assistant nurses (OR 1.5, 95% CI (1.1-2.0)) and HCW-cleaning (OR 1.9, 95% CI (1.4-2.5)). Respiratory-related absence from work in the past year was reported by 1.4% of non-HCW, 3.0% of HCW-cleaning, 2.9% of nurses, and 1.6% of assistant nurses. Taking smoking and age into account, there was still significantly increased respiratory-related absence from work in nurses (OR 2.0, 95% CI (1.1-3.8)) and in HCW-cleaning (OR 2.1, 95% CI (1.2-3.7)).

CONCLUSIONS

HCW in Sweden, especially those with cleaning tasks, reported more respiratory symptoms and respiratory-related absence from work than the general working population. There is a need for longitudinal studies with detailed information on both occupational exposures and socioeconomic factors to explore what influences respiratory-related absence from work among HCW.

Post-hire asthma among insect-rearing workers

OBJECTIVE

To evaluate the incidence of post-hire asthma (PHA) among insect-rearing workers, defined as asthma, the symptoms of which appeared after hire at the current workplace.

METHODS

We surveyed the health of workers at three insect-rearing facilities and an associated office facility. We calculated the incidence and estimated hazard ratios for PHA.

RESULTS

Post-hire asthma incidence in 157 insect-rearing workers was 16.2 per 1000 person-years compared with 9.2 per 1,000 person-years in 70 office workers. Workers with predominant exposure to Lepidoptera had an incidence of 26.9 per 1000 person-years and a hazard ratio of 5.5 (95% confidence interval: 1.6 to 23.9) adjusted for sex, race, and parental asthma. In contrast, the presence of specific immunoglobulin E to Lepidoptera antigens was not associated with PHA.

CONCLUSION

Insect-rearing workers had a high incidence of PHA, primarily accounted for by workplace exposure to Lepidoptera.

Occupation and three-year incidence of respiratory symptoms and lung function decline: the ARIC Study

Background

Specific occupations are associated with adverse respiratory health. Inhalation exposures encountered in these jobs may place workers at risk of new-onset respiratory disease.

Methods

We analyzed data from 8,967 participants from the Atherosclerosis Risk in Communities (ARIC) study, a longitudinal cohort study. Participants included in this analysis were free of chronic cough and phlegm, wheezing, asthma, chronic bronchitis, emphysema, and other chronic lung conditions at the baseline examination, when they were aged 45-64 years. Using data collected in the baseline and first follow-up examination, we evaluated associations between occupation and the three-year incidence of cough, phlegm, wheezing, and airway obstruction and changes in forced expiratory volume in one second (FEV₁) and forced vital capacity (FVC) measured by spirometry. All associations were adjusted for age, cigarettes per day, race, smoking status, and study center.

Results

During the approximately three-year follow-up, the percentage of participants developing chronic cough was 3%; chronic phlegm, 3%; wheezing, 3%; and airway obstruction, defined as FEV₁ < lower limit of normal (LLN) and FEV₁/FVC < LLN, 2%. The average annual declines in FEV₁ and FVC were 56 mL and 66 mL, respectively, among men and 40 mL and 52 mL, respectively, among women. Relative to a referent category of managerial and administrative support occupations, elevated risks of new-onset chronic cough and chronic phlegm were observed for mechanics and repairers (chronic cough: RR: 1.81, 95% CI: 1.02, 3.21; chronic phlegm: RR: 2.10, 95% CI: 1.23, 3.57) and cleaning and building service workers (chronic cough: RR: 1.85, 95% CI: 1.01, 3.37; chronic phlegm: RR: 2.28, 95% CI: 1.27, 4.08). Despite the elevated risk of new-onset symptoms, employment in cleaning and building services was associated with attenuated lung function decline, particularly among men, who averaged annual declines in FEV₁ and FVC of 14 mL and 23 mL, respectively, less than the declines observed in the referent population.

Conclusions

Employment in mechanic and repair jobs and cleaning and building service occupations are associated with increased incidence of respiratory symptoms. Specific occupations affect the respiratory health of adults without pre-existing respiratory health symptoms and conditions, though long-term health consequences of inhalation exposures in these jobs remain largely unexplored.

Is childhood asthma associated with educational level and longest-held occupation?

Children with asthma can experience chronic morbidity that may interfere with education and career progression. The authors investigated retrospectively whether a history of childhood asthma is associated with educational level and longest-held occupation, by gender. Cross-sectional analysis included a nationally representative sample of 10,452 adults aged ≥20 years who participated in the US National Health and Nutrition Examination Survey (2001-2004). Logistic regression was used to assess associations between a childhood-asthma history and educational level, employment, and longest-held occupation. An estimated 6.9% of men and 5.8% of women had a childhood-asthma history. Persons with a childhood-asthma history tended to have a higher educational level than those with no asthma history. Among those who ever worked, and after adjustment for age and race/ethnicity, men with a childhood-asthma history were more likely to work in health-diagnosing occupations, other professional occupations, and as cooks; women with a childhood-asthma history were more likely to work in management-related, entertainment-related, and health service occupations. Compared with those with no asthma history, persons with a childhood-asthma history tended to achieve a higher educational level and, if they worked, were more likely to work in particular occupations.

Predictors of early cessation of dairy farming in the French Doubs province: 12-year follow-up

BACKGROUND

A healthy worker effect due to respiratory disability has been noted in the farming population, but other factors may also interfere. Little has been published about factors influencing the early cessation of work in self-employed dairy farmers.

METHODS

Two hundred and nineteen dairy farmers were included from a cohort constituted in eastern France in 1993-1994 with a 12-year follow-up. Spirometric data, personal, and farm characteristics were registered. Cox models with delayed entry in which age was the time-scale were applied to identify the baseline predictive factors of the early cessation of dairy farming.

RESULTS

Working in a modern farm was protective against early cessation of dairy farming (hazard ratio: 0.36 [95% CI: 0.16-0.81]), especially in men. Having asthma was a predictive factor of early cessation, especially in women (hazard ratio: 16.12 [95% CI: 3.28-79.12]).

CONCLUSIONS

The most predictive factors of early cessation of dairy farming were health related in women and farm related in men.