Occupational exposure and new-onset asthma in the population-based Telemark study: a 5-year follow-up.

OBJECTIVES: This study aimed to estimate the incidence of asthma and assess the association between job exposure matrix (N-JEM) assigned occupational exposure, self-reported occupational exposure to vapour, gas, dust and fumes (VGDF), mould, damages from moisture and cold, and new-onset asthma. We also aimed to assess the corresponding population attributable fraction (PAF) for ever exposure to VGDF. DESIGN: Longitudinal population-based respiratory health study. SETTING: Responders from the baseline Telemark Study in south-eastern Norway were followed up from 2013 to 2018. PARTICIPANTS: 7120 participants, aged 16-55, were followed during a 5-year period. MAIN OUTCOME MEASURES: New-onset asthma and its association with self-reported occupational exposure to VGDF, data from the N-JEM and self-reported workplace conditions were assessed using logistic regression adjusted for gender, age, smoking and body mass index. The PAF was calculated using the PUNAF command in STATA. RESULTS: There were 266 (3.7%) cases of new-onset asthma and an incidence density of 7.5 cases per 1000 person-years. A statistically significant association was found for ever exposed to VGDF with an OR of 1.49 (95% CI 1.15 to 1.94), weekly OR 2.00 (95% CI 1.29 to 3.11) and daily OR 2.46 (95% CI 1.39 to 4.35) exposure to VGDF. The corresponding PAF for ever exposed to VGDF was 17% (95% CI 5.4% to 27.8%) and the risk of asthma onset increased with frequent VGDF exposure, indicating a possible exposure-response relationship (p=0.002 for trend). The N-JEM exposure group, accidental peak exposure to irritants had an increased risk of new-onset asthma, OR 2.43 (95% CI 1.21 to 4.90). A significant association was also found for self-reported exposure to visible damages due to moisture 1.51 (95% CI 1.08 to 2.11), visible and smell of mould 1.88 (95% CI 1.32 to 2.68), 1.55 (95% CI 1.12 to 2.16) and cold environment 1.41 (95% CI 1.07 to 1.86). CONCLUSION: Participants had elevated ORs for asthma associated with self-reported and N-JEM-assigned exposures. A PAF of 17% indicates that work-related asthma is still common. The possible exposure-response relationship suggests that reducing occupational VGDF exposure frequency could prevent the onset of asthma.

Loss to 5-year follow-up in the population-based Telemark Study: risk factors and potential for bias.

OBJECTIVES: This study aimed to characterise participants lost to follow-up and identify possible factors associated with non-participation in a prospective population-based study of respiratory health in Norway. We also aimed to analyse the impact of potentially biased risk estimates associated with a high proportion of non-responders. DESIGN: Prospective 5-year follow-up study. SETTING: Randomly selected inhabitants from the general population of Telemark County in south-eastern Norway were invited to fill in a postal questionnaire in 2013. Responders in 2013 were followed-up in 2018. PARTICIPANTS: 16 099 participants aged 16-50 years completed the baseline study. 7958 responded at the 5-year follow-up, while 7723 did not. MAIN OUTCOME MEASURES: χ2 test was performed to compare demographic and respiratory health-related characteristics between those who participated in 2018 and those who were lost to follow-up. Adjusted multivariable logistic regression models were used to assess the relationship between loss to follow-up, background variables, respiratory symptoms, occupational exposure and interactions, and to analyse whether loss to follow-up leads to biased risk estimates. RESULTS: 7723 (49%) participants were lost to follow-up. Loss to follow-up was significantly higher for male participants, those in the youngest age group (16-30 years), those in lowest education level category and among current smokers (all p<0.001). In multivariable logistic regression analysis, loss to follow-up was significantly associated with unemployment (OR 1.34, 95% CI 1.22 to 1.46), reduced work ability (1.48, 1.35 to 1.60), asthma (1.22, 1.10 to 1.35), being woken by chest tightness (1.22, 1.11 to 1.34) and chronic obstructive pulmonary disease (1.81, 1.30 to 2.52). Participants with more respiratory symptoms and exposure to vapour, gas, dust and fumes (VGDF) (1.07 to 1.00-1.15), low-molecular weight (LMW) agents (1.19, 1.00 to 1.41) and irritating agents (1.15, 1.05 to 1.26) were more likely to be lost to follow-up. We found no statistically significant association of wheezing and exposure to LMW agents for all participants at baseline (1.11, 0.90 to 1.36), responders in 2018 (1.12, 0.83 to 1.53) and those lost to follow-up (1.07, 0.81 to 1.42). CONCLUSION: The risk factors for loss to 5-year follow-up were comparable to those reported in other population-based studies and included younger age, male gender, current smoking, lower educational level and higher symptom prevalence and morbidity. We found that exposure to VGDF, irritating and LMW agents can be risk factors associated with loss to follow-up. Results suggest that loss to follow-up did not affect estimates of occupational exposure as a risk factor for respiratory symptoms.

Excessive Daytime Sleepiness and Associated Factors in Military Search and Rescue Personnel.

BACKGROUND: Abnormal excessive daytime sleepiness (EDS) has been reported worldwide, but too little is known about EDS and its determinants in Search and Rescue (SAR) populations. We aimed to determine the prevalence of abnormal EDS and contributing factors among Royal Norwegian Air Force (RNoAF) SAR helicopter personnel.METHODS: In this cross-sectional study, a total of N = 175 RNoAF SAR personnel completed an electronic survey including socio-demographic and lifestyle questions. The Epworth Sleepiness Scale (ESS) was used as both a continuous and categorical outcome variable to measure EDS.RESULTS: Abnormal EDS defined by ESS was found in 41% of the participants in this study. We observed no associations between socio-demographic and lifestyle factors and abnormal EDS in this study. DISCUSSION: There is a high prevalence of abnormal EDS in the current RNoAF SAR population. Despite this elevated level of fatigue, we did not find that the socio-demographic and lifestyle factors assessed in this study were associated with abnormal EDS in RNoAF SAR helicopter personnel. Also unusually, the study cohort did not demonstrate higher scores in factors found to change ESS scores in similar study populations (e.g., caffeine use, tobacco use, exercise level). Further research is required to investigate other factors (organizational, operational) that may be associated with abnormal EDS in this and other SAR populations.Akter R, Larose TL, Sandvik J, Fonne V, Meland A, Wagstaff AS. Excessive daytime sleepiness and associated factors in military search and rescue personnel. Aerosp Med Hum Perform. 2021; 92(12):975-979.

Aeromedical Evaluation for an F-16 Candidate with Incomplete Paraplegia.

BACKGROUND: A candidate with paraplegia contacted the Institute of Aviation Medicine, Oslo, requesting a medical examination and medical certification for flying back seat on an F-16 Fighting Falcon. Thorough aeromedical examinations, including specialist evaluations, were initiated for the final decision to be made. CASE REPORT: Almost 13 yr earlier the candidate had acquired spinal cord damage at neurological level L1 after falling 4 m (13 ft) from out of a window. The CT scans showed luxation of the 12th thoracic vertebra with fracture and dislocation of the 1st lumbar vertebra. He went for surgery, where fixation of the 12th thoracic vertebra to the 1st lumbar vertebra was performed. He developed syringomyelia 1 yr postoperatively and was re-operated on twice in the following years. He was now in a wheelchair, but engaged himself in several sport activities such as sledge-hockey and sit-skiing, participating in several Paralympics. DISCUSSION: With respect to the general principles of aviation medicine, several considerations had to be taken into account before a medical certification could be given. The risks associated with an F-16 flight in relationship to the candidate's general health and the fixation of his spinal cord had to be evaluated. Also, his ability to perform required tasks during the flight and in case of an emergency was an important issue discussed. Finally, the candidate's medical and physical condition should not present a considerable risk to flight safety. After extensive specialist consultations and in-depth discussions, the candidate was given medical certification to fly back seat in a F-16. Chahal-Kummen M, Strand T-E, Owe JO, Gulliksen E, Wagstaff AS. Aeromedical evaluation for an F-16 candidate with incomplete paraplegia. Aerosp Med Hum Perform. 2016; 87(11):968-971.